PHOENIX BIOTECH ACQUISITION CORP.CERO THERAPEUTICS HOLDINGS, INC.

2201 Broadway,201 Haskins Way, Suite 705

Oakland,230
South San Francisco, CA 9461294080

April 15, 2024

Dear Phoenix Biotech Acquisition Corp. stockholder:Stockholders:

On behalf of the Board of Directors of Phoenix Biotech Acquisition Corp. (the “Company,” “PBAX” “we,” “ours” or “us”), I

We are pleased to invite you to attend ourthe 2024 Special Meeting of Stockholders (the “Special Meeting”). We hope you can join us. of CERo Therapeutics Holdings, Inc. (the “Company” or “CERo”), which will be held at 5:00 p.m., Eastern Time, on April 30, 2024. The Special Meeting will be held at 11:00 AM Eastern Time on December 16, 2022. We will be holding the Special Meeting via live webcast.in virtual meeting format only. You will be able tomay attend the Special Meeting, submit questions and vote and submit your questions onlineshares electronically during the special meetingSpecial Meeting by visiting visiting: https://www.cstproxy.com/phoenixbiotech/2022cero/sm2024

Details regarding the business to be conducted at the Special Meeting are more fully described in the accompanying proxy statement for the 2024 Special Meeting (the “proxy statement”). The NoticeOther than the proposals described in the proxy statement, the Company’s board of directors (the “Board”) is not aware of any other matters to be presented for a vote at the Special Meeting.

Your vote is important. Whether or not you plan to virtually attend the Special Meeting, we encourage you to vote as soon as possible to ensure that your shares are represented. Information about voting methods is set forth in the accompanying proxy statement.

Only CERo stockholders of record at the close of business on March 20, 2024 will be entitled to vote at the Special Meeting and any adjournment or postponement hereof.

On behalf of the Company, thank you for your continued support.

Sincerely,

THIS PROXY STATEMENT AND ENCLOSED PROXY CARD ARE

FIRST BEING MADE AVAILABLE ON OR ABOUT APRIL 15, 2024.

CERO THERAPEUTICS HOLDINGS, INC.

201 Haskins Way, Suite 230
South San Francisco, CA 94080

NOTICE OF 2024 SPECIAL MEETING OF STOCKHOLDERS

TO BE HELD ON APRIL 30, 2024

Dear Stockholders:

NOTICE IS HEREBY GIVEN that the 2024 Special Meeting of Stockholders of CERo Therapeutics Holdings, Inc. (the “Notice”“Company” or “CERo”), the proxy statement is also available will be held on April 30, 2024, at https://www.cstproxy.com/phoenixbiotech/2022.5:00 p.m. Eastern Time. The Special Meeting will be held in a virtual meeting format only. We are first mailing these materials to our stockholders on or about November 22, 2022.

As discussed inholding the enclosed proxy statement,meeting for the purpose of the Special Meeting is to considerconsidering and vote upon the following proposals (the “Proposals”):acting upon:

Each

The Company’s board of directors (the “Board”) has fixed the Charter Amendment Proposal andrecord date for the Trust Amendment Proposal is cross-conditionedSpecial Meeting as March 20, 2024. Only stockholders of record at the close of business on the approval of each other. The Adjournment Proposal will only be presentedthat date may vote at the Special Meeting if thereor any adjournment or postponement thereof. A complete list of the Company’s registered stockholders as of the close of business on the record date will be available to the Company’s stockholders for examination for the 10 days before the Special Meeting at the Company’s offices at 201 Haskins Way, Suite 230, South San Francisco, CA 94080 and during the Special Meeting at https://www.cstproxy.com/cero/sm2024.

You will be able to attend and listen to the Special Meeting, vote, and submit your questions during the Special Meeting by visiting https://www.cstproxy.com/cero/sm2024 and entering your 16-digit control number included on your proxy card or on the instructions that accompanied your proxy materials. We believe that hosting a “virtual” meeting will minimize travel expenses and enable greater stockholder attendance and participation from any location around the world, provide for cost savings to the Company, and reduce the environmental impact of the Special Meeting. The Special Meeting will be governed by the Company’s rules of conduct and procedures that will be posted at https://www.cstproxy.com/cero/sm2024.

Your vote is important. Whether or not you plan to virtually attend the Special Meeting, we encourage you to vote as soon as possible to ensure that your shares are not sufficient votes to approverepresented. Information about voting methods is set forth in the Charter Amendment Proposal and the Trust Amendment Proposal. accompanying proxy statement.

Each of the Charter Amendment Proposal,matters to be acted upon at the Trust Amendment Proposal, and the Adjournment Proposal isSpecial Meeting are more fully described in the accompanying proxy statement.

Only holders of record of Class A common stock The Board recommends that you vote “FOR” each of the Company, par value $0.0001 per share (“Class A common stock”proposals outlined in the accompanying proxy statement.

The accompanying proxy statement is being mailed to stockholders commencing on or “public shares”),about April 15, 2024. Please carefully review the accompanying proxy statement and act as soon as possible to vote your shares of Class B common stock ofwhether or not you intend on attending the Company, par value $0.0001 per share (“Class B common stock” or “founder shares”Special Meeting. If you attend the virtual Special Meeting and together with the Class A common stock, the “common stock”) at the close of business on November 10, 2022 (the “Record Date”) are entitleddecide to notice ofvote during the Special Meeting, and to vote at the Special Meeting and any adjournments or postponements of the Special Meeting.

A complete list of stockholders of record entitled to vote at the Special Meeting will be available for ten days before the Special Meeting at our principal executive offices for inspectionyou may withdraw your proxy by stockholders during ordinary business hours for any purpose germane to the Special Meeting.

The Charter Amendment Proposal and the Trust Amendment Proposal are essential to the overall implementation of the Board’s plan to extend the business combination period as contemplated by Charter Amendment Proposal and the Trust Amendment Proposal (the “Extension”). The purpose of the Charter Amendment Proposal, the Trust Amendment Proposal and, if necessary, the Adjournment Proposal, is to allow us additional time to finalize the terms and consummate the Business Combination.

As previously announced, we entered into a Business Combination Agreement dated October 30, 2022 (the “Business Combination Agreement,” and together with the other agreements and transactions contemplated by the Business Combination Agreement, the “Business Combination”), with Intrinsic Medicine, Inc., a Delaware corporation (“Intrinsic”), and OM Merger Sub, Inc., a Delaware corporation and a wholly-owned subsidiary of PBAX (“Merger Sub”), pursuant to which Merger Sub will merge with and into Intrinsic, with Intrinsic surviving as a wholly-owned subsidiary of PBAX. In connection with the consummation of the Business Combination, we will change our corporate name to “Intrinsic Medicine, Inc.” The Board has unanimously (i) approved and declared advisable the Business Combination Agreement, the Business Combination and the other transactions contemplated thereby, and (ii) resolved to recommend approval of the Business Combination Agreement and related matters by our stockholders. We will hold a meeting of stockholders to consider and approve the proposed Business Combination, and a proxy statement/prospectus will be sent to all of our stockholders of record.

We and the other parties to the Business Combination Agreement are currently working towards satisfaction of the conditions to completion of the Business Combination, including drafting the necessary filings with the SEC related to the transaction, but have determined that there will not be sufficient time before January 8, 2023 (the current deadline in the charter for completion an initial business combination) to hold a special meeting to obtain the requisite stockholder approval of, and to consummate, the Business Combination. Management believes that it can close the Business Combination before April 8, 2023 (i.e., the end of the three-month extension period) or within the additional three one-month extension periods thereafter. Accordingly, the Board believes that it is in the best interests of our stockholders to obtain the Extension.

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension becomes effective, prior to effecting the Charter Amendment and the Trust Amendment, Phoenix Biotech Sponsor LLC (the “sponsor”) (or one or more of its affiliates, members or third-party designees) (the “Lender”) shall make a deposit into the trust account of the Company (the “Trust Account”) of $325,000. In addition, if the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension becomes effective, in the event that the Company has not consummated the Business Combination by April 8, 2023, without approval of the public stockholders, the Company may, by resolution of the Board if requested by the sponsor, and upon five business days’ advance notice prior to the applicable Termination Date extend the Termination Date up to three times, each by one additional month (for a total of up to three additional months to complete the Business Combination), provided that a Lender will deposit into the Trust Account: (I) for the first such monthly extension, $100,000; (II) for the second such monthly extension, $125,000 and (III) for the third such monthly extension, $150,000, for an aggregate deposit of up to $375,000. If the Company completes the Business Combination, it will, at the option of the Lender, repay the amounts loaned under the promissory note(s) or convert a portion or all of the amounts loaned under such promissory note(s) into units at a price of $10.00 per unit, which units will be identical to the private placement units issued to the Sponsor at the time of the Initial Public Offering. If the Company does not complete the Business Combination by the final applicable Extended Termination Date, such promissory notes will be repaid only from funds held outside of the Trust Account. “Extended Termination Date” means April 8, 2023, or in the case of one or more further extensions of the Termination Date as described above, then May 8, 2023, June 8, 2023 or July 8, 2023, as the case may be.

In order to mitigate the risk of us being deemed to have been operating as an unregistered investment company (including under the subjective test of Section 3(a)(1)(A) of the Investment Company Act of 1940, as amended (the “1940 Act”)), we expect that, on or prior to October 5, 2023, if the Termination Date has been extended

through that date (which is not permitted by the Extension and, therefore, would require approval by our stockholders at a future date) and we have not yet completed an initial Business Combination, then we will instruct Continental, the trustee with respect to the Trust Account, to liquidate the U.S. government treasury obligations or money market funds held in the Trust Account and thereafter to hold all funds in the Trust Account in cash until the earlier of consummation of our initial Business Combination or liquidation. As a result, following such liquidation, we will likely receive minimal interest, if any, on the funds held in the Trust Account, which would reduce the dollar amount our public shareholders would receive upon any redemption or liquidation of the Company.

Pursuant to the amended and restated bylaws of PBAX (the “bylaws”), a majority of the shares of common stock entitled to vote, represented at the Special Meeting or by proxy, will constitute a quorum for the transaction of business at the Special Meeting. Approval of the Charter Amendment Proposal and the Trust Amendment Proposal requires the affirmative vote of holders of at least 65% of all then outstanding shares of common stock entitled to vote thereon at the Special Meeting. Approval of the Adjournment Proposal requires the affirmative vote of the holders of a majority of the issued and outstanding shares of common stock cast in respect of the Adjournment Proposal and entitled to vote thereonvoting at the Special Meeting.

Under

If you have any questions or need assistance voting your shares, please contact the Delaware General Corporation Law (the “DGCL”Company’s proxy solicitor, Advantage Proxy, Inc. (“Advantage Proxy”), shares that are voted “abstain”at (877) 870-8565 (toll free) or “withheld” are counted as present for purposesby e-mail at ksmith@advantageproxy.com.

TABLE OF CONTENTS

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This proxy statement (this “proxy statement”) contains forward-looking statements within the meaning of determining whether a quorum is present at the Special Meeting. Abstentions and withheld votes will have the same effect as a vote “AGAINST” the Charter Amendment Proposal and the Trust Amendment Proposal, and will have no effect on the Adjournment Proposal. Because the Proposals are “non-discretionary” items, your broker will not be able to vote uninstructed shares for anySection 27A of the Proposals. If there are any proposals that are “discretionary” items, then the broker may cast a vote on such proposals, resulting in the shares being counted for purposesSecurities Act of determining whether a quorum is present1933, as amended (the “Securities Act”), and a broker “non-vote” is deemed to occur with respect to each “non-discretionary” item. However, since none of the Proposals are “discretionary” items, if you do not provide voting instructions, your shares will not be voted and will not be counted as present for purposes of determining whether a quorum is present.

You are not being asked to vote on any business combination at this time. In connection with the Charter Amendment Proposal and the Trust Amendment Proposal, public stockholders may elect to redeem their public shares for a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Company to pay taxes (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for use by, the Company to pay franchise and income taxes), divided by the number of the then outstanding shares of the Company’s common stock issued in our initial public offering, which we refer to as our “Initial Public Offering,” which shares we refer to as the “public shares,” and which election we refer to as the “Election.”

Public stockholders may make an Election whether or not they are holders as of the Record Date and whether or not they vote “FOR” the Charter Amendment Proposal or the Trust Amendment Proposal. If the Charter Amendment Proposal and the Trust Amendment Proposal are approved by the requisite vote of stockholders, the remaining holders of public shares will retain their right to redeem their public shares if and when the Business Combination is submitted to the stockholders, subject to any limitations set forth in our charter. In addition, public stockholders who do not make the Election will be entitled to have their public shares redeemed for cash if we have not completed a business combination by the Extended Termination Date. A public stockholder, together with any of his, her or its affiliates or any other person with whom he, she or it is acting in concert or as a “group” (as defined under Section 1321E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), will be restricted from redeeming in the aggregate his, her or its shares or, if part. All statements other than statements of such a group, the group’s shares, with respect to 20% or more of the public shares issued in the Initial Public Offering. The sponsor and the other holders of founder shares prior to our Initial Public Offering (or their permitted transferees) (collectively, the “initial stockholders”) have agreed to waive their redemption rights with respect to any founder shares, public shares and shares of Class A common stock underlying the private placement units (the “private placement units” and such shares, the “private placement shares”) sold in a private placement simultaneously with the closing of the Initial Public Offering (the “Concurrent Private Placement”) they may hold in connection with the consummation of the Charter Amendment Proposal and the Trust Amendment

Proposal, and such shares will be excluded from the pro rata calculation used to determine the per-share redemption price. Our initial stockholders have also agreed to vote any founder shares, public shares and private placement shares owned by them in favor of the Charter Amendment Proposal and the Trust Amendment Proposal, which represent approximately 23% of the voting power of the Company as of the Record Date. These holders have also agreed to vote their shares in favor of all other Proposals being presented at the Special Meeting.

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension is implemented, then in accordance with the Trust Agreement, the Trust Account will not be liquidated (other than to effectuate the redemptions) until the earlier of (a) receipt by the Trustee of a termination letter (in accordance with the terms of the trust agreement) or (b) the Extended Termination Date. Approval of the Charter Amendment Proposal and the Trust Amendment Proposal will constitute consent for us to instruct the Trustee to (i) remove from the Trust Account an amount (the “Withdrawal Amount”) equal to the number of public shares properly redeemed multiplied by the per-share price, equal to the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Company to pay taxes (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for use by, the Company to pay franchise and income taxes), divided by the number of the then outstanding public shares and (ii) deliver to the holders of such redeemed public shares their portion of the Withdrawal Amount. The remainder of such funds shall remain in the Trust Account and be available for use by us to complete a business combination on or before April 8, 2023 (or up to July 8, 2023, as applicable). Public stockholders who do not redeem their public shares now will retain their redemption rights and their ability to vote on any business combination through April 8, 2023 (or up to July 8, 2023, as applicable) if the Extension is approved.

TO EXERCISE YOUR REDEMPTION RIGHTS, YOU MUST DEMAND IN WRITING THAT YOUR PUBLIC SHARES BE REDEEMED FOR A PRO RATA PORTION OF THE FUNDS HELD IN THE TRUST ACCOUNT AND TENDER YOUR SHARES TO OUR TRANSFER AGENT AT LEAST TWO BUSINESS DAYS PRIOR TO THE VOTE AT THE SPECIAL MEETING. IN ORDER TO EXERCISE YOUR REDEMPTION RIGHT, YOU NEED TO IDENTIFY YOURSELF AS A BENEFICIAL HOLDER AND PROVIDE YOUR LEGAL NAME, PHONE NUMBER AND ADDRESS IN YOUR WRITTEN DEMAND. YOU MAY TENDER YOUR SHARES BY EITHER DELIVERING YOUR SHARE CERTIFICATE TO THE TRANSFER AGENT OR BY DELIVERING YOUR SHARES ELECTRONICALLY USING THE DEPOSITORY TRUST COMPANY’S DEPOSIT WITHDRAWAL AT CUSTODIAN (“DWAC”) SYSTEM. IF THE BUSINESS COMBINATION IS NOT COMPLETED, THEN THESE SHARES WILL BE RETURNED TO YOU OR YOUR ACCOUNT. IF YOU HOLD THE SHARES IN STREET NAME, YOU WILL NEED TO INSTRUCT THE ACCOUNT EXECUTIVE AT YOUR BANK OR BROKER TO WITHDRAW THE SHARES FROM YOUR ACCOUNT IN ORDER TO EXERCISE YOUR REDEMPTION RIGHTS.

Any demand for redemption, once made, may be withdrawn at any time until the deadline for exercising redemption requests and thereafter, with our consent, until the vote is taken with respect to the Charter Amendment Proposal and the Trust Amendment Proposal. Furthermore, if a holder of a public share delivered its certificate in connection with an Election of its redemption and subsequently decides prior to the applicable date not to elect to exercise such rights, it may simply request that the transfer agent return the certificate (physically or electronically).

For illustrative purposes, based on funds in the Trust Account of approximately $179.6 million on September 30, 2022, the estimated per-share conversion price would have been approximately $10.26. The closing price of the Company’s common stock on September 30, 2022 was $10.09. Accordingly, if such prices were to remain the same until the date of the Special Meeting, exercising redemption rights would result in a public stockholder receiving $0.17 more for each share than if such stockholder sold the shares in the open market. The Company cannot assure stockholders that they will be able to sell their shares of common stock in the open market, even if the market price per share is higher than the redemption price stated above, as there may not be sufficient liquidity in its securities when such stockholders wish to sell their shares.

The Company reserves the right at any time to cancel the Special Meeting and not to submit the Charter Amendment Proposal or the Trust Amendment Proposal to stockholders or implement the Charter Amendment or the Trust Amendment.

YOUR VOTE IS VERY IMPORTANT, REGARDLESS OF THE NUMBER OF SHARES OF COMMON STOCK YOU OWN. To ensure your representation at the Special Meeting, please complete and return the enclosed proxy card or submit your proxy by following the instructionshistorical facts contained in this proxy statement, including statements regarding the Company’s future results of operations and on your proxy card. Please submit your proxy promptly whetherfinancial position, business strategy, drug candidates, planned preclinical studies and clinical trials, results of preclinical studies, clinical trials, research and development (“R&D”) costs, regulatory approvals, timing and likelihood of success, as well as plans and objectives of management for future operations, are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that are in some cases beyond the Company’s control and may cause the Company’s actual results, performance or notachievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

In some cases, you expect to attendcan identify forward-looking statements by terms such as “may,” “will,” “should,” “would,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “believe,” “estimate,” “predict,” “potential,” or “continue” or the Special Meeting. Submitting a proxy now will NOT prevent you from being able to vote in person (which would include presence at a virtual meeting) at the meeting. If you hold your shares in “street name,” you should instruct your broker, banknegative of these terms or other nominee how to votesimilar expressions. Forward-looking statements contained in accordance with the voting instruction form you receive from your broker, bank or other nominee.

After careful consideration of all relevant factors, the Board of Directors has determined that each of the proposals are advisable and recommends that you vote or give instruction to vote “FOR” such proposals.

If you have any questions regarding this proxy statement you may contact Okapi Partners LLC, our proxy solicitor, toll free at (877) 259-6290 (banks and brokers call at (212) 297-0720).include, but are not limited to, statements about:

We have based these forward-looking statements largely on the Company’s current expectations and projections about the Company’s business, the industry in which we operate and financial trends that we believe may affect the Company’s business, financial condition, results of operations and prospects, and these forward-looking statements are not guarantees of future performance or development. These forward-looking statements speak only as of the date of this proxy statement and are subject to a number of risks, uncertainties and assumptions described in “Risk Factors” and elsewhere in this proxy statement. Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified, you should not rely on these forward-looking statements as predictions of future events. The events and circumstances reflected in the Company’s forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in the forward-looking statements. Except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained herein until after we distribute this proxy statement, whether as a result of any new information, future events or otherwise.

In addition, statements that “we believe” and similar statements reflect the Company’s beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this proxy statement, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and the Company’s statements should not be read to indicate that the Company has conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain, and you are cautioned not to unduly rely upon these statements.

This proxy statement is dated November 21, 2022,includes trademarks, tradenames and is first being mailedservice marks that are the property of other organizations. Solely for convenience, trademarks and tradenames referred to stockholders onin this proxy statement appear without the ® and ™ symbols, but those references are not intended to indicate, in any way, that the Company will not assert, to the fullest extent under applicable law, the Company’s rights, or about November 22, 2022.that the applicable owner will not assert its rights, to these trademarks and tradenames.

NOTICE OF201 Haskins Way, Suite 230
South San Francisco, CA 94080

PROXY STATEMENT

2024 SPECIAL MEETING OF STOCKHOLDERS

OF PHOENIX BIOTECH ACQUISITION CORP.

TO BE HELD ON DECEMBER 16, 2022APRIL 30, 2024

To

GENERAL INFORMATION

Why did I receive this proxy statement?

This proxy statement and the Stockholdersenclosed proxy card are being sent to you in connection with the solicitation of Phoenix Biotech Acquisition Corp.:

NOTICE IS HEREBY GIVEN that aproxies by CERo for use at the 2024 Special Meeting of Stockholders (the “Special Meeting”) of Phoenix Biotech Acquisition Corp. (the “Company,” “PBAX” “we,” “ours”, or “us”), a Delaware corporation,at any adjournments or postponements thereof. This proxy statement summarizes the information that you need to make an informed decision on the proposals to be considered at the Special Meeting. The Special Meeting will be held virtually via live interactive webcast on December 16, 2022, at 11:the internet on April 30, 2024, 5:00 AMp.m. Eastern Time. We will be holdingIf you held shares of the Special Meeting via live webcast. You will be ableCompany’s Common Stock, on March 20, 2024 (the “Record Date”), you are invited to attend the Special Meeting at https://www.cstproxy.com/cero/sm2024 and vote and submit your questions online duringon the proposals described below under the heading “What am I voting on?”

When is the record date for the Special Meeting?

The record date for determination of stockholders entitled to vote at the Special Meeting by visiting www.cstproxy.com/phoenixbiotech/2022.is the close of business on March 20, 2024.

The purpose of

What am I voting on?

There are four proposals scheduled to be voted on at the Special Meeting will be to consider and vote upon the following proposals (the “Proposals”):Meeting:

How does the Board recommend that I vote?

The Company’s Board has fixed the close of business on November 10, 2022 as the Record Date for the Special Meeting and only holders of shares of record atrecommends that time will be entitled to notice of and toyou vote at the Special Meeting or any adjournment or adjournments thereof. A complete list of stockholders of record entitled to vote at the Special Meeting will be available for ten days before the Special Meeting at our principal executive offices for inspection by stockholders during ordinary business hours for any purpose germane to the Special Meeting.

THE BOARD UNANIMOUSLY RECOMMENDS A VOTE “FOR” THE CHARTER AMENDMENT PROPOSAL, THE TRUST AMENDMENT PROPOSAL AND, IF PRESENTED, THE ADJOURNMENT PROPOSAL.your shares:

Your vote is important. If you are a stockholder of record, please sign, date, and return your proxy card as soon as possible to make sure that your shares are represented at the Special Meeting. If you are a stockholder of record, you may also cast your vote online at the Special Meeting. If your shares are held in an account at a brokerage firm or bank, you must instruct your broker or bank how to vote your shares, or you may cast your vote online at the Special Meeting by obtaining a proxy from your brokerage firm or bank. Your failure to vote or instruct your broker or bank how to vote will have the same effect as voting “AGAINST” the Charter Amendment Proposal and the Trust Amendment Proposal, and an abstention will have the same effect as voting “AGAINST” the Charter Amendment Proposal and the Trust Amendment Proposal.

TABLE OF CONTENTS

QUESTIONS AND ANSWERS ABOUT THE SPECIAL MEETING

The questions and answers below highlight only selected information from this proxy statement and only briefly address some commonly asked questions about the Special Meeting and the Proposals to be presented at the Special Meeting. The following questions and answers do not include all the information that may be important to stockholders. Stockholders are urged to read this proxy statement, including the Annexes and the other documents referred to herein, in its entirety.

We are a blank check company incorporated on June 8, 2021 for the purpose of effecting a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses. On October 8, 2021, we consummated our Initial Public Offering of 17,500,000 units (the “public units” and, together with the private placement units, the “units”). Simultaneously with the consummation of the Initial Public Offering, we consummated a private placement (the “Concurrent Private Placement”) of 885,000 private placement units. Each public unit consists of one share of Class A common stock and one-half of one warrant (a “public warrant”). Each whole warrant entitles the holder to purchase one share of Class A common stock at a price of $11.50 per share, subject to adjustment. The private placement units are identical to the units sold in the Initial Public Offering, subject to certain limited exceptions with respect to the warrants underlying such private placement units (the “private placement warrants” and, together with the public warrants, the “warrants”). The warrants will expire five years after the completion of our initial business combination, at 5:00 p.m., New York City time, or earlier upon redemption or liquidation.

Like many blank check companies, our charter provides for the return of the funds held in the Trust Account to the public stockholders if there is no qualifying business combination(s) consummated on or before a certain date (in our case, January 8, 2023). Our Board has determined that it is in the best interests of our stockholders to extend the date that we have to consummate an initial business combination to the Extended Termination Date in order to allow our stockholders to evaluate an initial business combination and for us to be able to potentially consummate an initial business combination, and is submitting these proposals to our stockholders to vote upon.

The approval of the Charter Amendment Proposal and the Trust Amendment Proposal is essential to the implementation of our Board’s plan to extend the date by which we must consummate our initial business combination. Approval of the Charter Amendment Proposal and the Trust Amendment Proposal is a condition to the implementation of the Extension.

We are not asking you to vote on an initial business combination at this time. We will file a separate proxy statement/prospectus pursuant to which we will seek approval of an initial business combination, among other things, at a separate special meeting. If the Extension is not approved, we may not be able to consummate an initial business combination. We urge you toWho can vote at the Special Meeting regarding the Extension.Meeting?

If the Charter Amendment Proposal and the Trust Amendment Proposal are not approved and we do not consummateyou were a business combination by January 8, 2023, in accordance with our charter, we will (i) cease all operations except for the purposeholder of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account including interest earned on the funds held in the Trust Account and not previously released to the Company to pay franchise and income taxes (less up to $100,000 of the net interest to pay dissolution expenses), divided by the number of then outstanding public shares, which redemption will completely extinguish public stockholders’ rights as stockholders (including

the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approvalrecord of the Company’s remaining stockholdersCommon Stock as of the close of business on March 20, 2024, the Record Date for the Special Meeting, you may vote your shares at the Special Meeting. As of the Record Date, there were shares 14,706,692 of Common Stock outstanding and entitled to vote. This number excludes treasury shares, as Company treasury shares will not be voted. Each stockholder has one vote for each share of Common Stock held as of the Board, dissolve and liquidate, subject in each case toRecord Date.

A list of the Company’s obligations under Delaware law to providestockholders of record will be open for claims of creditors and the requirements of other applicable law.

While we may utilize funds from the Trust Account to payexamination by any potential income or franchise taxes, we will not utilize any funds from our Trust Account to pay any potential excise taxes that may become due upon a redemption of the public shares, including in connection with a liquidation of the Company in 2023 if we do not effect a business combinationstockholder beginning ten days prior to the Termination Date. ToSpecial Meeting at the extent there are insufficient funds in our working capitalCompany’s offices located at 201 Haskins Way, Suite 230, South San Francisco, CA 94080. If you would like to fundview the payment of any potential excise taxes that may become due upon a redemption of public shares in connection with a liquidation oflist, please contact the Company in 2023 if we do not effect a business combination prior toCompany’s proxy solicitor, Advantage Proxy., by telephone at (877) 870-8565 or by e-mail at ksmith@advantageproxy.com. In addition, the Termination Date, our Sponsor has agreed to contribute to us (which may be by working capital loan) funds necessary to make any such potential excise tax payment without using proceeds (including interest income) from the Trust Account.

Therelist will be no redemption rights or liquidating distributions with respect to our warrants, which will expire worthless inavailable for inspection by stockholders on the event of our winding up. In the event of a liquidation, the holders of our Class B common stock will not receive any monies held in the Trust Account as a result of their ownership of the Class B common stock.

Our Board believes, however, that stockholders should have an opportunity to evaluate an initial business combination, and if approved by our stockholders, the Company should have an opportunity to consummate an initial business combination. Accordingly, our Board is proposing the Charter Amendment and the Trust Amendment to extend the date by which we have to complete our initial business combination until the Extended Termination Date and to allow for the Election. The Extension would give us the opportunity to hold a stockholder vote for the approval of an initial business combination, and if approved by our stockholders, consummate an initial business combination. If you do not elect to redeem your public shares, you will retain the right to vote on any proposed initial business combination in the future and the right to redeem your public shares in connection with such initial business combination.

Moreover, voting “FOR” the Charter Amendment Proposal or the Trust Amendment Proposal will not affect your right to seek redemption of your public shares in connection with the vote to approve a business combination. Our Board recommends that you vote “FOR” the Charter Amendment Proposal and the Trust Amendment Proposal, but expresses no opinion as to whether you should redeem your public shares.

We will not proceed with the Charter Amendment or the Trust Amendment if redemptions of our public shares cause us to have less than $5,000,001 of net tangible assets following approval of the Charter Amendment Proposal and the Trust Amendment Proposal.

If presented, our Board recommends that you vote “FOR” the Adjournment Proposal.

In addition, if we are able to consummate an initial business combination beforevirtual meeting website during the Special Meeting, we will not hold the Special Meeting and we will not proceed with the Extension.Meeting.

Our sponsor, directors, officers, advisors, or their affiliates may purchase public units, public shares or public warrants in privately negotiated transactions or in the open market either prior to or following the completion of our initial business combination. There is no limit on the number of shares our sponsor, directors, officers, advisors, or their affiliates may purchase in such transactions, subject to compliance with applicable law and OTC Exchange rules. If they engage in such transactions, they will not make any such purchases when they are in possession of any material nonpublic information not disclosed to the seller of such public shares or if such purchases are prohibited by Regulation M under the Exchange Act. If our sponsor, directors, officers, advisors, or their affiliates engage in such transactions and disclose material nonpublic information to such sellers, they would expect to enter into non-disclosure agreements with such sellers that prohibits the further dissemination of any disclosed material nonpublic information. We do not currently anticipate that such purchases, if any, would constitute a tender offer subject to the tender offer rules under the Exchange Act or a going-private transaction subject to the going-private rules under the Exchange Act; however, if the purchasers determine at the time of any such purchases that the purchases are subject to such rules, the purchasers will comply with such rules. Any such purchases will be reported pursuant to Section 13 and Section 16 of the Exchange Act to the extent such purchasers are subject to such reporting requirements. None of the funds held in the Trust Account will be used to purchase public shares or public warrants in such transactions. Such a purchase could include a contractual acknowledgement that

such stockholder, although still the record holder of such public shares, is no longer the beneficial owner thereof and therefore agrees not to exercise its redemption rights and could include a contractual provision that directs such stockholder to vote such shares in a manner directed by the purchaser.

Although our sponsor, directors, officers, advisors, and their affiliates have no current commitments, plans or intentions to engage in such transactions and have not formulated any terms or conditions for any such transactions, if those current commitments, plans, or intentions change, the purpose of any such purchases of public units or public shares could be to vote such shares in favor of the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal and thereby increase the likelihood of obtaining stockholder approval of the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal. The purpose of any such purchases of public warrants could be to reduce the number of public warrants outstanding or to vote such warrants on any matters submitted to the warrantholders for approval in connection with the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal. Any such purchases of our securities may result in the approval of the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal that may not otherwise have been possible. In addition, if such purchases are made, the public “float” of the units, common stock or warrants may be reduced and the number of beneficial holders of our securities may be reduced, which may make it difficult to maintain or obtain the quotation, listing or trading of our securities on a national securities exchange.

Although our sponsor, directors, officers, advisors and their affiliates have no current commitments, plans or intentions to engage in such transactions and have not formulated any terms or conditions for any such transactions, if those current commitments, plans or intentions change, our sponsor, officers, directors and/or their affiliates may identify the stockholders with whom our sponsor, officers, directors or their affiliates may pursue privately negotiated purchases by either the stockholders contacting us directly or by our receipt of redemption requests submitted by stockholders following our mailing of proxy materials in connection with the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal. To the extent that our sponsor, officers, directors, advisors or their affiliates enter into a private purchase, they would identify and contact only potential selling stockholders who have expressed their election to redeem their shares for a pro rata share of the Trust Account or vote against our initial business combination, whether or not such stockholder has already submitted a proxy with respect to the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal but only if such shares have not already been voted at the stockholder meeting related to the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal. Our sponsor, officers, directors, advisors or their affiliates will select which stockholders to purchase shares from based on the negotiated price and number of shares and any other factors that they may deem relevant and will only purchase shares if such purchases comply with Regulation M under the Exchange Act and the other federal securities laws.

Any purchases by our sponsor, officers, directors and/or their affiliates who are affiliated purchasers under Rule 10b-18 under the Exchange Act will only be made to the extent such purchases are able to be made in compliance with Rule 10b-18, which is a safe harbor from liability for manipulation under Section 9(a)(2) and Rule 10b-5 of the Exchange Act. Rule 10b-18 has certain technical requirements that must be complied with in order for the safe harbor to be available to the purchaser. Our sponsor, officers, directors and/or their affiliates will not make purchases of common stock if the purchases would violate Section 9(a)(2) or Rule 10b-5 of the Exchange Act. Any such purchases will be reported pursuant to Section 13 and Section 16 of the Exchange Act to the extent such purchases are subject to such reporting requirements.

If the Charter Amendment Proposal and Trust Amendment Proposal are approved, any holder of public shares may redeem all or a portion of their public shares at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account as of two business days prior to such approval, including any interest earned on the Trust Account deposits (which interest shall be net of taxes payable), divided by the number of then outstanding public shares. However, the Company may not redeem our public shares in an amount that would cause our net tangible assets to be less than $5,000,001.

If the Charter Amendment Proposal and Trust Amendment Proposal are approved, any holder of public shares may redeem all or a portion of their public shares at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account as of two business days prior to such approval, including any interest earned on the Trust Account deposits (which interest shall be net of taxes payable), divided by the number of then outstanding public shares. However, the Company may not redeem our public shares in an amount that would cause our net tangible assets to be less than $5,000,001.

If the Charter Amendment Proposal and the Trust Amendment Proposal are not approved and we do not consummate a business combination by January 8, 2023, in accordance with our charter, we will (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account including interest earned on the funds held in the Trust Account and not previously released to the Company to pay franchise and income taxes (less up to $100,000 of the net interest to pay dissolution expenses), divided by the number of then outstanding public shares, which redemption will completely extinguish public stockholders’ rights as stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the Company’s remaining stockholders and the Board, dissolve and liquidate, subject in each case to the Company’s obligations under Delaware law to provide for claims of creditors and the requirements of other applicable law.

While we may utilize funds from the Trust Account to pay any potential income or franchise taxes, we will not utilize any funds from our Trust Account to pay any potential excise taxes that may become due upon a redemption of the public shares, including in connection with a liquidation of the Company in 2023 if we do not effect a business combination prior to the Termination Date. To the extent there are insufficient funds in our working capital to fund the payment of any potential excise taxes that may become due upon a redemption of public shares in connection with a liquidation of the Company in 2023 if we do not effect a business combination prior to the Termination Date, our Sponsor has agreed to contribute to us (which may be by working capital loan) funds necessary to make any such potential excise tax payment without using proceeds (including interest income) from the Trust Account.

There will be no redemption rights or liquidating distributions with respect to our warrants, which will expire worthless in the event of our winding up. In the event of a liquidation, the holder of our Class B common stock, our sponsor, will not receive any monies held in the Trust Account as a result of its ownership of the Class B common stock.

Upon approval of the Charter Amendment Proposal and the Trust Amendment Proposal by the requisite number of votes, the Charter Amendment and Trust Agreement set forth in Annex A and Annex B hereto, respectively, will become effective. We will remain a reporting company under the Exchange Act and our public units, public shares and public warrants will remain publicly traded.

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved, the removal of the Withdrawal Amount from the Trust Account will reduce the amount remaining in the Trust Account and increase the percentage interest of our common stock held by our initial stockholders as a result of their ownership of the Class B common stock.

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved but we do not complete our initial business combination by the Extended Termination Date (or, if such date is further extended at a duly called special meeting, such later date), we will: (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter subject to lawfully available funds therefor, redeem 100% of the shares of Class A common stock in consideration of a per-share price, payable in cash, equal to the quotient obtained by dividing (A) the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Company to pay its taxes (less up to $100,000 of such net interest to pay dissolution expenses), by (B) the total number of then outstanding public shares, which redemption will completely extinguish rights of the public stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the

approval of the remaining stockholders and the Board, in accordance with applicable law, dissolve and liquidate, subject in each case to the Company’s obligations under the DGCL to provide for claims of creditors and other requirements of applicable law.

There will be no redemption rights or liquidating distributions with respect to our warrants, which will expire worthless in the event of our winding up. In the event of a liquidation, the holders of our Class B common stock (including the sponsor) will not receive any monies held in the Trust Account as a result of their ownership of the Class B common stock.

Notwithstanding the foregoing, we will not proceed with the Extension if redemptions of our public shares would cause us to have less than $5,000,001 of net tangible assets following approval of the Charter Amendment Proposal and the Trust Amendment Proposal, and the consequences will be the same as if the Charter Amendment Proposal and the Trust Amendment Proposal was not approved, as described above.

In order to mitigate the risk of us being deemed to have been operating as an unregistered investment company (including under the subjective test of Section 3(a)(1)(A) of the 1940 Act), we expect that, on or prior to October 5, 2023, if the Termination Date has been extended through that date (which is not permitted by the Extension and, therefore, would require approval by our stockholders at a future date) and we have not yet completed an initial Business Combination, then we will instruct Continental, the trustee with respect to the Trust Account, to liquidate the U.S. government treasury obligations or money market funds held in the Trust Account and thereafter to hold all funds in the Trust Account in cash until the earlier of consummation of our initial Business Combination or liquidation. As a result, following such liquidation, we will likely receive minimal interest, if any, on the funds held in the Trust Account, which would reduce the dollar amount our public shareholders would receive upon any redemption or liquidation of the Company.

There will be no redemption rights or liquidating distributions with respect to our warrants, which will expire worthless in the event of our winding up. In the event of a liquidation, the holders of our Class B common stock will not receive any monies held in the Trust Account as a result of their ownership of the Class B common stock.

Once the public warrants become exercisable, we may call the public warrants for redemption:

The private placement warrants are identical to the public warrants underlying the units sold in the Initial Public Offering, except that the private placement warrants and the common stock issuable upon the exercise of the private placement warrants will not be transferable, assignable, or salable until after the completion of an initial business combination, subject to certain limited exceptions. Additionally, the private placement warrants will be exercisable on a cashless basis and will be non-redeemable so long as they are held by the initial purchasers or their permitted transferees. If the private placement warrants are held by someone other than the initial purchasers or their permitted transferees, the private placement warrants will be redeemable by the Company and exercisable by such holders on the same basis as the public warrants.

In addition, if (x) we issue additional shares of Class A common stock or equity-linked securities for capital raising purposes in connection with the closing of our initial business combination at an issue price or effective issue price of less than $9.20 per share (with such issue price or effective issue price to be determined in good faith by us and in the case of any such issuance to our sponsor or its affiliates, without taking into account any founder shares held by our initial stockholders or such affiliates, as applicable, prior to such issuance) (the “Newly Issued Price”), (y) the aggregate gross proceeds from such issuances represent more than 60% of the total equity proceeds, and interest thereon, available for the funding of our initial business combination on the date of the completion of our initial business combination (net of redemptions), and (z) the volume-weighted average trading price of our shares of Class A common stock during the 20 trading day period starting on the trading day prior to the day on which we complete our initial business combination (such price, the “Market Value”) is below $9.20 per share, the exercise price of the warrants will be adjusted (to the nearest cent) to be equal to 115% of the higher of the Market Value and the Newly Issued Price, and the $18.00 per share redemption trigger price will be adjusted (to the nearest cent) to be equal to 180% of the higher of the Market Value and the Newly Issued Price.

If the Company is unable to complete an initial business combination prior to January 8, 2023, and the Company liquidates the funds held in the Trust Account, holders of warrants will not receive any of such funds with respect to their warrants, nor will they receive any distribution from the Company’s assets held outside of the Trust Account with the respect to such warrants. Accordingly, the warrants may expire worthless. If the Company calls the public warrants for redemption, management will have the option to require all holders that wish to exercise the public warrants to do so on a “cashless basis,” as described in the warrant agreement. The exercise price and number of common shares issuable upon exercise of the

public warrants may be adjusted in certain circumstances including in the event of a stock dividend, extraordinary dividend or recapitalization, reorganization, merger, or consolidation. If the Company is unable to complete an initial business combination prior to January 8, 2023, and the Company liquidates the funds held in the Trust Account, holders of warrants will not receive any of such funds with respect to their warrants, nor will they receive any distribution from the Company’s assets held outside of the Trust Account with respect to such warrants. Accordingly, the warrants may expire worthless.

Stockholder of Record: Shares Registered in Your Name.Name

If, on the Record Date, your shares were registered directly in your name with ourCERo’s transfer agent, Continental Stock Transfer & Trust Company, then you are a stockholder of record. As a stockholder of record, you may vote in personlive online at the Special Meetingmeeting or vote by proxy. Whether or not you plan to attend the Special Meeting, in person, we urgethe Company urges you to fill out and return the enclosed proxy card that may be mailed to you or vote by proxy over the telephone or on the internet as instructed below to ensure your vote is counted.

Beneficial Owner: Shares Registered in the Name of a Broker or Bank.Bank If on the Record Date your shares were held, not in your name, but rather in an account at a brokerage firm, bank, dealer, or other similar organization, then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwarded to you by that organization. As a beneficial owner, you have the right to direct your broker or other agent on how to vote the shares in your account. You are also invited to attend the Special Meeting. However, since you are not the stockholder of record, you may not vote your shares in person at the Special Meeting unless you request and obtain a valid proxy from your broker or other agent.

If, on the Record Date, your shares were held, not in your name, but rather in an account at a brokerage firm, bank, dealer or other similar organization, then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwardedname.” The organization holding your account is considered to you by that organization.be the stockholder of record for purposes of voting at the Special Meeting. As a beneficial owner, you have the right to direct your broker or other agent onregarding how to vote the shares in your account. You are also invited to attend the Special Meeting in person online.via the internet at https://www.cstproxy.com/cero/sm2024. However, sincebecause you are not the stockholder of record, you may not vote your shares in personlive online at the Special Meeting unless you first request and obtain a valid legal proxy from your broker or other agent.

How can I attend the Special Meeting?

If you are a stockholder of record or a beneficial owner as of the Record Date, you are invited to attend the Special Meeting live via the internet at https://www.cstproxy.com/cero/sm2024. You must then e-mail a copy (a legible photograph is sufficient) ofhave your legal proxy to Continental Stock Transfer & Trust Company at proxy@continentalstock.com. Beneficial owners who e-mail a valid legal proxy will be issued a 12-digit

meeting16-digit control number listed on the proxy card or in the instructions that will allow themaccompanied your proxy materials to registerenter the meeting. The webcast starts at 5:00 p.m. Eastern Time. You may vote and submit questions while attending the meeting on the internet. Instructions on how to attend and participate in the Special Meeting. Beneficial owners who wishMeeting via the internet, including how to attenddemonstrate proof of stock ownership, will be posted at https://www.cstproxy.com/cero/sm2024.

What if I return the Special Meeting online should contact Continental Stock Transfer & Trustproxy card to the Company no later than 11:00 AM Eastern Time on December 13, 2022but do not make specific choices?

If you return a signed, dated proxy card to obtain this information.the Company without making any voting selections, the named proxies will vote your shares:

You can pre-register to attend the Special Meeting in person online starting December 9, 2022 (five business days prior to the meeting). Enter the URL address into your browser, and enter your 12-digit meeting control number, name, and email address. Once you pre-register, you can vote or enter questions in the chat box. Prior to or at the start of the Special Meeting you will need to re-log in using your 12-digit meeting control number and will also be prompted to enter your 12-digit meeting control number if you vote in person online during the Special Meeting. The Company recommends that you log in at least 15 minutes before the Special Meeting to ensure you are logged in when the Special Meeting starts.

If your shares are held in “street name,” you may attend the Special Meeting. If you plan to vote at the Special Meeting, you will need to have a legal proxy from your broker, bank or other nominee or, if you would like to join and not vote, Continental Stock Transfer & Trust Company can issue you a guest control number with proof of ownership. Either way, you will need to contact Continental Stock Transfer & Trust Company at the number or email address above, to receive a 12-digit meeting control number and gain access to the Special Meeting or otherwise contact your broker, bank, or other nominee as soon as possible, to do so. Please allow up to 72 hours prior to the Special Meeting for processing your 12-digit meeting control number.

If you do not have Internet capabilities, you can listen only to the Special Meeting by dialing +1 800-450-7155 (toll-free) if within the U.S. or Canada, or +1 857-999-9155 (standard rates apply) if outside of the U.S. and Canada, when prompted enter the pin 3681459#. This is listen only, you will not be able to vote or enter questions during the Special Meeting.

In order to exercise your redemption rights, you must, (i) (A) hold public shares, or (B) if you hold public shares through units, elect to separate your units into the underlying public shares and public warrants prior to exercising your redemption rights with respect to the public shares and (ii) prior to 5:00 p.m. Eastern time on December 14, 2022 (two business days before the Special Meeting), (A) submit a written request to the Company’s transfer agent that the Company redeem your public shares for cash and (B) deliver your stock to the Company’s transfer agent physically or electronically through The Depository Trust Company (“DTC”). The address of Continental Stock Transfer & Trust Company, the Company’s transfer agent, is listed under the question “Who can help answer my questions?” below. The Company requests that any request for redemption include the identity as to the beneficial owner making such request. Electronic delivery of your stock generally will be faster than delivery of physical stock certificates.

A physical stock certificate will not be needed if your stock is delivered to the Company’s transfer agent electronically. In order to obtain a physical stock certificate, a stockholder’s broker and/or clearing broker, DTC and the Company’s transfer agent will need to act to facilitate the request. It is the Company’s understanding that stockholders should generally allot at least one week to obtain physical certificates from the transfer agent. However, because the Company does not have any control over this process or over the brokers or DTC, it may take significantly longer than one week to obtain a physical stock certificate. If it takes longer than anticipated to obtain a physical certificate, stockholders who wish to redeem their shares may be unable to obtain physical certificates by the deadline for exercising their redemption rights and thus will be unable to redeem their shares.

Any demand for redemption, once made, may be withdrawn at any time until the deadline for exercising redemption requests and thereafter, with the Company’s consent, until the vote is taken with respect to the Charter Amendment. If you delivered your shares for redemption to the Company’s transfer agent and

decide within the required timeframe not to exercise your redemption rights, you may request that the Company’s transfer agent return the shares (physically or electronically). You may make such request by contacting the Company’s transfer agent at the phone number or address listed under the question “Who can help answer my questions?”

Your shares will be counted towards the quorum only if you submit a valid proxy (or your broker, bank or other nominee submits one on your behalf) or if you vote in person online at the Special Meeting. Abstentions will be counted towards the quorum requirement, but broker non-votes will not. A quorum of stockholders is necessary to hold a valid meeting. If there is no quorum, the chairman of the meeting may adjourn the Special Meeting to another date.

Okapi Partners LLC

1212 Avenue of the Americas, 17^th Floor

New York, NY 10036

Telephone: (877) 259-6290

(banks and brokers can call at (212) 297-0720)

Email: info@okapipartners.com

You may also contact the Company at:

Phoenix Biotech Acquisition Corp.

2201 Broadway, Suite 705

Oakland, CA 94612

(215) 731-9450

To obtain timely delivery, stockholders must request the materials no later than five business days prior to the Special Meeting.

You may also obtain additional information about the Company from documents filed with the SEC by following the instructions in the section entitled “Where You Can Find More Information”.

If you intend to seek redemption of your public shares, you will need to send a letter demanding redemption and deliver your stock (either physically or electronically) to the Company’s transfer agent prior to 5:00 p.m., New York time, on December 14, 2022, the second business day prior to the Special Meeting. If you have questions regarding the certification of your position or delivery of your stock, please contact:

Continental Stock Transfer & Trust Company

One State Street Plaza, 30^th Floor

New York, New York 10004

Attention: Mark Zimkind

E-mail: mzimkind@continentalstock.com

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained in this proxy statement, which reflect our current views with respect to future events and financial performance, and any other statements of a future or forward-looking nature, constitute “forward-looking statements” for the purposes of federal securities laws. Our forward-looking statements include, but are not limited to, statements regarding our or our management’s expectations, hopes, beliefs, intentions or strategies regarding the future. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “would” and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. Forward-looking statements in this proxy statement may include, for example, statements about:

The forward-looking statements contained in this proxy statement are based on our current expectations and beliefs concerning future developments and their potential effects on us. There can be no assurance that future developments affecting us will be those that we have anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond our control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to, those factors described under the heading “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2021 and our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2022 and June 30, 2022. Should one or more of these risks or uncertainties materialize, or should any of our assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. We undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

THE SPECIAL MEETING

General

We are furnishing this proxy statement to our stockholders as part of the solicitation of proxies by our Board for use at the Special Meeting in lieu of the 2022 annual meeting of stockholders, and at any adjournment or postponement thereof. This proxy statement is first being furnished to our stockholders on or about November 22, 2022. This proxy statement provides you with information you need to know to be able to vote or instruct your vote to be cast at the Special Meeting.

Date, Time and Place of the Special Meeting

The enclosed proxy is solicited by the Board in connection with the Special Meeting to be held on December 16, 2022 at 11:00 AM Eastern time for the purposes set forth in the accompanying Notice. We will be holding the Special Meeting via live webcast. You will be able to attend the Special Meeting, vote and submit your questions online during the Special Meeting by visiting www.cstproxy.com/phoenixbiotech/2022.

The principal executive office of the Company is 2201 Broadway, Suite 705, Oakland, CA 94612, and its telephone number is (215) 731-9450.

Purpose of the Special Meeting

At the Special Meeting, you will be asked to consider and vote upon the following matters:

Each

The Company does not expect that any matters other than the election of directors, ratification of the Charter Amendment Proposalappointment of Wolf as the Company’s independent registered public accounting firm, approval of the issuance of shares of the Common Stock, pursuant to Nasdaq Listing Rule 5635, and the Trust Amendment Proposal is cross-conditioned on the approval of each other.any other matters, if necessary, described in this proxy statement will be brought before the Special Meeting. The Adjournment Proposalpersons appointed as proxies will onlyvote in their discretion on any other matters that may properly come before the Special Meeting or any postponements or adjournments thereof, including any vote to postpone or adjourn the Special Meeting.

How do I revoke my proxy?

If you are a stockholder of record, you may revoke your proxy by (1) following the instructions on your proxy card and entering a new vote over the Internet or by telephone by the cutoff time of 11:59 p.m. Eastern Time on April 29, 2024, (2) attending the Special Meeting online and voting by following the instructions at or (3) by filing an instrument in writing revoking the proxy or submitting another duly executed proxy card bearing a later date with the Company’s Secretary. Any written notice of revocation or subsequent proxy card must be presentedreceived by the Company’s Secretary prior to the taking of the vote at the Special Meeting. Such written notice of revocation or subsequent proxy card should be hand delivered to the Company’s Secretary or sent to the Company’s offices at 201 Haskins Way, Suite 230, South San Francisco, CA 94080, Attention: Secretary.

How many shares must be present or represented to conduct business at the Special Meeting?

A quorum of stockholders is necessary to hold a valid special meeting of stockholders. A quorum will be present if the stockholders holding at least a majority of the voting power of the outstanding shares entitled to vote are present, in person or by remote communication or by proxy, at the Special Meeting. On the Record Date, there were 14,706,692 shares of Common Stock outstanding and entitled to vote. Thus, the holders of at least 7,353,347 shares of Common Stock must be present or represented by proxy at the Special Meeting to have a quorum.

Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your broker, bank or other nominee) or if you vote live online at the Special Meeting. Abstentions and shares represented by broker non-votes are counted for the purpose of determining whether a quorum is present. If there are not sufficientinsufficient votes to constitute a quorum at the time of the Special Meeting, the holders of Common Stock representing a majority of the voting power present at the Special Meeting or the presiding officer may adjourn the Special Meeting to another place (if any), date or time and from time to time.

How are votes counted?

Votes will be counted by the inspector of election appointed for the Special Meeting, who will separately count, for Proposal 1 to ratify the appointment of Wolf as the Company’s independent registered public accounting firm (which Proposal 1 is considered a “routine matter”); votes “FOR” and “AGAINST,” and abstentions, and for Proposals 2 and 3 to approve the Charter Amendmentissuance of shares of the Common Stock, pursuant to Nasdaq Listing Rule 5635 (which Proposals 2 and 3 are considered a “non-routine matter”); votes “FOR” and “AGAINST,” abstentions, and, if applicable, broker non-votes; for Proposal 4 to approve an amendment to the Plan to increase the number of shares of Common Stock available for issuance under the Plan (which Proposal 4 is considered a “non-routine matter”), votes “FOR” and “AGAINST,” and abstentions and, if applicable, broker non-votes; and for Proposal 5 to approve an adjournment of the special meeting, if necessary, to permit further solicitation and vote of proxies in the event that there are insufficient votes in favor of Proposals 2 and 3 (which Proposal 5 is considered a “non-routine matter”), votes “FOR” and “AGAINST,” and abstentions and, if applicable, broker non-votes.

What are “broker non-votes”?

A “broker non-vote” occurs when your broker, bank or other agent has not received voting instructions from the beneficial owner of the shares and the Trust Amendment Proposal.broker, bank or other agent cannot vote the shares because the matter is considered “non-routine.” Under the rules that govern brokers who are voting shares held in street name, brokers have the discretion to vote your “uninstructed” shares on “routine” matters, but not on “non-routine” matters. Proposals 2, 3, 4 and 5 are considered to be “non-routine” under these rules such that your broker may not vote your shares on this proposal in the absence of your voting instructions. Conversely, Proposal 1 is considered to be “routine” matters under these rules and thus if you do not return voting instructions to your broker by its deadline, your shares may be voted by your broker in its discretion on Proposal 1.

What is the voting requirement to approve each of the proposals?

Proposal 1—Ratification of the Appointment of the Company’s Independent Registered Public Accounting Firm for the Fiscal Year Ending December 31, 2024

The Charter Amendment proposal to ratify the appointment of Wolf as the Company’s independent registered public accounting firm requires the approval by a majority of the votes properly cast for such matter. Abstentions and broker non-votes, if any, will have no effect on the outcome of this proposal.

Proposal 2—Approval, subject to certain conditions, of the issuance of shares of the Common Stock, in accordance with Nasdaq Listing Rule 5635, upon (i) the conversion of the Series A Preferred Stock, (ii) the conversion of the Series B Preferred Stock, (iii) the exercise of Common Warrants and (iv) the Trust Amendment exercise of Preferred Warrants and conversion of the underlying Series A Preferred Stock

The proposal to approve the issuance of shares of the Common Stock, pursuant to Nasdaq Listing Rule 5635, requires the approval by a majority of the votes properly cast for such matter. Abstentions and broker non-votes, if any, will have no effect on the outcome of this proposal.

Proposal are essential3—Approval, subject to certain conditions, of the issuance of shares of the Common Stock, in accordance with Nasdaq Listing Rule 5635, pursuant to the overall implementationCommitted Equity Financings

The proposal to approve the issuance of shares of the Board’s planCommon Stock, pursuant to extendNasdaq Listing Rule 5635, requires the business combination period as contemplatedapproval by Charter Amendment Proposal and the Trust Amendment Proposal (the “Extension”). The purposea majority of the Charter Amendment votes properly cast for such matter. Abstentions and broker non-votes, if any, will have no effect on the outcome of this proposal.

Proposal 4: The approval of the Trust Amendment Plan, as amended to increase the number of shares of Common Stock available for issuance under the Plan by an additional 2,000,000 shares.

The proposal to approve the Plan, as amended, requires the approval by a majority of the votes properly cast for such matter. Abstentions and broker non-votes, if any, will have no effect on the outcome of this proposal.

Proposal and,5—Approval of an adjournment of the Special Meeting, if necessary, to permit further solicitation and vote of proxies in the Adjournment Proposal,event that there are insufficient votes in favor of Proposals 2 and 3

The proposal to approve of an adjournment of the Special Meeting requires the approval by a majority of the votes properly cast for such matter. Abstentions and broker non-votes, if any, will have no effect on the outcome of this proposal.

How do I vote my shares of CERo Common Stock?

Stockholders may vote shares of the Company’s Common Stock using any of the following means:

Voting by Proxy Cards. A registered stockholder may vote shares until voting is completed at the Special Meeting by requesting and returning a duly completed and executed proxy card. All proxy cards received by us that have been properly signed and have not been revoked will be voted in accordance with the instructions contained in the proxy cards.

Voting by Telephone or Internet. A registered stockholder may vote shares until voting is completed at the Special Meeting by calling the toll-free number indicated on the proxy card and following the recorded instructions or by accessing the website indicated on the proxy card and following the instructions provided. When a stockholder votes by telephone or internet, his, her or its vote is recorded immediately.

Voting by Internet During the Special Meeting. Instructions on how to allowattend and vote at the Special Meeting are described at https://www.cstproxy.com/cero/sm2024. If a stockholder attends the Special Meeting and votes his, her or its shares during the meeting via the voting instructions described at https://www.cstproxy.com/cero/sm2024, then any previous votes that were submitted by the stockholder, whether by internet, telephone or mail, will be superseded by the vote that such stockholder casts during the Special Meeting. Further, if the shares are held of record by a broker and a stockholder wishes to vote at the Special Meeting, he, she or it must obtain a proxy issued in his, her or its name from the record holder in accordance with the materials and instructions for voting provided by his, her or its broker.

Voting by “Street Name” Stockholders. If stockholders hold shares in “street name,” then those stockholders may vote in accordance with the materials and instructions for voting the shares provided by their broker, bank or other nominee. If “street name” stockholders wish to vote shares at the Special Meeting, then they must obtain proxies from their broker, bank or other nominee in order to vote their shares at the Special Meeting in accordance with the materials and instructions for voting provided by his, her or its broker, bank or other nominee. If a “street name” stockholder does not vote by proxy or otherwise give voting instructions to their broker, such shares will not be voted by the broker for Proposals 2, 3, 4 and 5 at the Special Meeting.

Changing Votes. A registered stockholder may change his, her or its vote at any time before it is voted at the Special Meeting by (1) delivering a proxy revocation or another duly executed proxy bearing a later date to CERo Therapeutics Holdings, Inc., 201 Haskins Way, Suite 230, South San Francisco, CA 94080, Attention: Secretary, which revocation or later-dated proxy is received by the Company’s Secretary prior to the taking of the vote at the Special Meeting; (2) voting again by telephone or internet in the manner described above by the cutoff time of 11:59 p.m. Eastern Time on April 29, 2024; or (3) attending the Special Meeting and voting via the internet during the Special Meeting using the procedures described at https://www.cstproxy.com/cero/sm2024. Attending the Special Meeting via the internet will not revoke a proxy unless the stockholder actually votes via the internet during the Special Meeting. “Street name” stockholders who wish to revoke or change their votes after returning voting instructions to their broker, bank or other nominee may do so in accordance with the materials and instructions provided by their broker, bank or other nominee or by contacting such broker, bank or other nominee to effect the revocation or change of vote.

Who pays the cost for soliciting proxies?

The Company is making this solicitation and will pay the entire cost of preparing and distributing the proxy materials and soliciting votes. If you choose to access the proxy materials or vote over the Internet or by telephone, you are responsible for any Internet access or telephone charges that you may incur. The Company’s officers and employees may, without compensation other than their regular compensation, solicit proxies through further mailings, personal conversations, facsimile transmissions, e-mails, or otherwise. The Company will also reimburse brokers, banks, custodians, other nominees, and fiduciaries for forwarding these materials to their principals to obtain the authorization for the execution of proxies.

How can I find out the results of the Special Meeting?

Preliminary voting results will be announced at the Special Meeting. The Company will publish final results in a Current Report on Form 8-K that the Company expects to file with the U.S. Securities and Exchange Commission (the “SEC”) within four business days after the Special Meeting. If final voting results are not available at that time, the Company will disclose the preliminary results in a Current Report on Form 8-K and, within four business days after the final voting results are known to us, additional timefile an amended Current Report on Form 8-K to finalizedisclose the termsfinal voting results.

How and consummate the Business Combination.

As previously announced, weOn June 4, 2023, PBAX entered into a Business Combination Agreement dated October 30, 2022 (the “Business Combination Agreement,”with Legacy CERo and together with the other agreements and transactions contemplated by the Business Combination Agreement, the “Business Combination”), with Intrinsic Medicine, Inc., a Delaware corporation (“Intrinsic”), and OM Merger Sub, Inc., a Delaware corporation and a wholly-owned subsidiary of PBAX (“Merger Sub”), pursuant to which Merger Sub will mergemerged with and into Intrinsic,Legacy CERo, with IntrinsicLegacy CERo surviving as a wholly-owned subsidiary of PBAX. In connection with the consummation of the Business Combination we will change ouron February 14, 2024, PBAX changed its corporate name to “Intrinsic Medicine,“CERo Therapeutics Holdings, Inc.” The Board has unanimously (i) approved and declared advisableAt the Business Combination Agreement, the Business Combination and the other transactions contemplated thereby, and (ii) resolved to recommend approvaltime of the Business Combination, Agreement and related matters by our stockholders. We will hold a meeting of stockholdersPBAX was publicly traded, having closed its initial public offering on October 8, 2021.

What is “Legacy CERo”?

References in this proxy statement to consider and approve the proposed Business Combination, and a proxy statement/prospectus will be sent“Legacy CERo” refer to all of our stockholders of record.

We and the other partiesCERo Therapeutics, Inc. prior to the Business Combination Agreement are currently working towards satisfactionclosing of the conditions to completionBusiness Combination.

Who can provide me with additional information and help answer my questions?

If you would like additional copies, without charge, of this proxy statement or if you have questions about the proposals being considered at the Special Meeting, including the procedures for voting your shares, you should contact Advantage, the Company’s proxy solicitor, by telephone at (877) 870-8565 or by e-mail at ksmith@advantageproxy.com.

DIRECTORS AND EXECUTIVE OFFICERS

As of April 1, 2024, the Company’s directors and executive officers were as follows:

Executive Officers

Brian G. Atwood has served as chairman (the “Chairman”) of the board of directors and chief executive officer (the “Chief Executive Officer”) since February 2024, and previously served as Chairman of PBAX from October 2021 the closing of the Business Combination in February 2024. Mr. Atwood serves as a Managing Director for Versant Ventures, a healthcare-focused venture capital firm that he co-founded in 1999. In 2015, Mr. Atwood co-founded Cell Design Labs, Inc., a biotechnology company focused on developing human cell engineering technology for the treatment of multiple diseases, including draftingcancer, where he served as President and Chief Executive Officer until 2017, when it was acquired by Gilead Sciences. Mr. Atwood serves on the necessary filingsboard of directors of Clovis Oncology, Inc. (Nasdaq: CLVS), and Atreca, Inc. (Nasdaq: BCEL), where he is Chairman. He also served on the board of directors of Immune Design Corp. from May 2008 until June 2016 (acquired by Merck in 2019), Veracyte, Inc., from its founding in 2008 until December 2016, OpGen Inc., from July 2007 until December 2017, Five Prime Therapeutics, from 2002 until March 2016, Cadence Pharmaceuticals, Inc. from March 2006 until its acquisition in March 2014, Helicos Biosciences from 2003 until September 2011, Pharmion Corporation from 2000 until its acquisition in March 2008, Trius Therapeutics, Inc. from February 2007 until its acquisition in September 2013 and Locust Walk Acquisition Corp. (Nasdaq: LWAC) from January 2021 until the consummation of its business combination in August 2021. Mr. Atwood holds a B.S. in Biological Sciences from the University of California, Irvine, a M.S. in Ecology from the University of California, Davis, and a M.B.A. from Harvard Business School.

Mr. Atwood was selected to serve on the Company’s board of directors because of his experience in the biotechnology industry, his years of business and leadership experience and his financial sophistication and expertise.

Charles Carter has served as the Company’s chief financial officer (the “Chief Financial Officer”) and secretary (the “Secretary”) since February 2024. Prior to the business combination, Mr. Carter served as a consulting finance executive for Legacy CERo through Danforth Advisors, LLC (“Danforth”) since February 2023, and a consultant for Danforth since May 2022. Prior to rejoining Danforth, Mr. Carter was Chief Financial Officer and Secretary of iCAD, Inc. (Nasdaq: ICAD) from May 2021 to May 2022. Previously, Mr. Carter was Chief Financial Officer of GI Dynamics, Inc. (“GI Dynamics”), a medical device company (ASX: GID, delisted July 2020) from December 2018 to April 2021. Prior to joining GI Dynamics in 2019, Mr. Carter was a finance consultant with Danforth from March 2018 to September 2019. Mr. Carter has also been the Chief Financial Officer of The Guild for Human Services, a not-for-profit community-based residential school and program for special needs students and adults, the Chief Financial Officer for Aeris Therapeutics, Inc. and Intelligent Medical Devices, Inc. and held senior finance leadership positions at Adnexus Therapeutics, Inc. and Transkaryotic Therapies, Inc./Shire, PLC. (Nasdaq: TKT; Nasdaq: SHPG) (“TKT”). Prior to TKT, Mr. Carter was a partner with Mercer Management Consulting, Inc. Mr. Carter holds an M.B.A. and an M.S. in Molecular Genetics from the University of Chicago and a B.A. in Biology from Colgate University.

Daniel Corey, M.D.,has served as the Company’s chief technology officer (the “Chief Technology Officer”) and a member of the board of directors since February 2024, and previously served as Chief Executive Officer, Chief Scientific Officer, a member of the board of directors of Legacy CERo from its inception in 2018 until the closing of the Business Combination of February 2024. Prior to founding Legacy CERo, from June 2012 to June 2018, Dr. Corey was a senior follow in the Division of Hematology at Stanford University, and from June 2010 to June 2012, Dr. Corey was a fellow at Stanford University’s Institute of Stem Cell Biology and Regenerative Medicine, where he was awarded a career development award from the National Heart Lung and Blood Center (“NHLBI”) for work studying hematopoiesis. Dr. Corey is a member of various medical-related societies, has eight U.S. patent applications outstanding and has written extensively in various medical publications. Dr. Corey has received various honors during his education and career, which, among others, include the Johnson and Johnson Innovation Award; the Siebel Stem Cell Scholar, Stanford University; the Stanford University Molecular Immunology Training Award; the NHLBI K12 Career Development Award, Stanford University; the NHLBI National Service Research Award, Duke University. Dr. Corey received a B.A. with honors from Brown University, received his M.D. from University of Washington School of Medicine and served as a fellow and a resident at Duke University.

Dr. Corey was selected to serve on the Company’s board of directors based on his substantial medical and scientific experience, and, in particular, his history with Legacy CERo and the creation of Chimeric Engulfment Receptor T cells.

Directors

Chris Ehrlich has served as vice chairman of the Company’s board of directors since February 2024, and previously served as the Chief Executive Officer of PBAX from October 2021 until the closing of the Business Combination in February 2024. From January 2021 to August 2021, he served as the Chief Executive Officer of Locust Walk Acquisition Corp (Nasdaq: LWAC) until it merged with eFFECTOR Therapeutics, Inc., where he currently serves on the board of directors. He is also the Principal of Ehrlich Bioventures, LLC, a consultancy working with emerging biopharma companies. He previously served as Senior Managing Director and the Global Head of Strategic Transactions at Locust Walk Partners from 2013 to 2021. He brings significant biotechnology industry, business development, venture capital experience, investment banking and SPAC experience. While at Locust Walk Partners, Mr. Ehrlich was involved with sourcing and leading multiple transactions for emerging biopharmaceutical companies, including the sale of Xyphos Biosciences, Inc. to Astellas in 2019 and the sale of Thar Pharmaceuticals to Grunenthal in 2018. Prior to Locust Walk Partners, he was a Managing Director at InterWest Partners (“InterWest”), a venture capital firm. At InterWest, he served on the boards of KAI Pharmaceuticals, a privately held pharmaceutical company (acquired by Amgen in 2012), Biomimetic Therapeutics, Inc., a biotechnology company (acquired by Wright Medical Technologies in 2013), Invuity, Inc., a medical technology company acquired by Stryker in 2018) and Xenon Pharmaceuticals, a biopharmaceutical company (Nasdaq: XENE). Prior to joining InterWest, Mr. Ehrlich worked as the Director of Licensing and Business Development at Purdue Pharma, in business development at Genentech, in venture capital at the U.S. Russia Investment Fund, and in biotechnology strategy development at L.E.K. Consulting. Mr. Ehrlich also currently serves on the board of directors of Prostate Management Diagnostics, Inc., on the advisory board of the Peter Michael Foundation, where he is a Senior Advisor, and on the healthcare at Kellogg advisory board at Northwestern University. Mr. Ehrlich has a B.A. in Government from Dartmouth College and an M.B.A. from the Kellogg Graduate School of Management at Northwestern University, where he is a frequent lecturer.

Mr. Ehrlich was selected to serve on the Company’s board of directors based on his substantial investment and acquisition experience in the biotechnology and biopharmaceutical industries and his experience serving as a director for various public and private companies.

Michael Byrnes has served as a member of the Company’s board of directors since February 2024. Mr. Byrnes has served as the Chief Financial Officer of eFFECTOR Therapeutics since December 2020. Previously, Mr. Byrnes was Senior Vice President of Finance at Principia Biopharma, Inc. from January 2020 until its acquisition by Sanofi in September 2020. Prior to that, Mr. Byrnes served as the Chief Financial Officer of Alkahest, Inc. from May 2018 to January 2020 and Chief Financial Officer of Ocera Therapeutics, Inc., from December 2014 until its acquisition by Mallinckrodt Pharmaceuticals in December 2017. Mr. Byrnes served as Corporate Controller of Maxygen, Inc. from March 2010 to December 2014 and prior to that, held finance positions of increasing responsibility from 2000 to 2010 with NeurogesX, Inc., Lipid Sciences, Inc. and ADAC Laboratories, Inc., a Philips Medical Systems company. Mr. Byrnes received his B.S.C. in Finance from Santa Clara University and an M.B.A. from California State University, Hayward.

Mr. Byrnes was selected to serve on the Company’s board of directors based on his substantial leadership and management experience in the biopharmaceutical industry.

Kathleen LaPorte has served as a member of the Company’s board of directors since February 2024, and previously served a member of PBAX’s board of directors from October 2021 until the closing of the Business Combination in February 2024. Ms. LaPorte is an experienced executive, founder and board member, focused on life sciences. She co-founded New Leaf Ventures, served as a General Partner of The Sprout Group, and was Chief Business Officer and Chief Executive Officer of Nodality Inc. Ms. LaPorte has served on sixteen public company boards and fourteen public company audit committees and numerous private company boards. Ms. Laporte currently serves as an independent director for Bolt Biotherapeutics (Nasdaq: BOLT), Precipio Diagnostics (Nasdaq: PRPO), 89Bio (Nasdaq: ENTB), Elysium Therapeutics, and Q32 Bio Inc. (Nasdaq: QTTB). Ms. LaPorte serves as the chair of the audit committees of Bolt Biotherapeutics, Precipio Diagnostics and Q32 Bio Inc. and as the chair of the compensation committee of 89Bio. She previously served on the California Institute for Regenerative Medicine, a state agency board. Ms. LaPorte has a B.S. degree in Biology from Yale University and a M.B.A. from the Stanford University Graduate School of Business.

Ms. LaPorte was selected to serve on the Company’s board of directors based on her extensive leadership and management experience in the life sciences industry.

Robyn Rapaport has served as a member of the Company board of directors since February 2024. Ms. Rapaport has served a principal overseeing alternative investments at Rapaport Capital since November 2021. Prior to that, Ms. Rapaport was an entrepreneur at the University of California, Los Angeles Anderson Venture Accelerator, from June 2019 to December 2020. Ms. Rapaport holds an M.B.A. from the University of California, Los Angeles and a B.A. from the University of Pennsylvania in history and consumer psychology.

Ms. Rapaport was selected to serve the Company’s board of directors based on her financial and operational experience.

Lindsey Rolfe, M.D., has served as a member of the Company’s board of directors since February 2024. Dr Rolfe has served as Chief Medical Officer at 3B Pharmaceuticals GmbH since August 2023 and previously served as Chief Medical Officer at Clovis Oncology Inc. from August 2015 to June 2023, and served as Senior Vice President of Clinical Development from 2010. At Clovis, Dr. Rolfe oversaw the development team that obtained approvals for Rubraca as an ovarian cancer treatment in the United States and Europe, and was responsible for all pre- and post-marketing medical activities. Dr. Rolfe has more than 20 years of drug development experience and previously served in senior oncology development roles at Celgene Corporation, Pharmion Corporation, Cambridge Antibody Technology, UCB Inc. and Celltech Group plc. In addition, Ms. Rolfe has served as an independent director at Atreca Inc. (Nasdaq: BCEL) since August 2019. Dr. Rolfe holds a BSc Anatomy and Bachelor of Medicine and Surgery from the University of Edinburgh, undertook post-graduate medical training in London, UK and obtained her post-graduate internal medicine qualification as a Member of the Royal College of Physicians. She has specialist accreditation in Pharmaceutical Medicine from the UK General Medical Council and is a Fellow of the Faculty of Pharmaceutical Medicine in the UK.

Dr. Rolfe was selected to serve on the Company’s board of directors based on her experience in leading drug discovery and development of therapeutics.

Family Relationships

There are no family relationships between the Company’s board of directors and any of the Company’s executive officers.

CORPORATE GOVERNANCE

Board of Directors

Director Independence

Nasdaq listing rules require that a majority of the board of directors of a company listed on Nasdaq be composed of “independent directors,” which is defined generally as a person other than an officer or employee of a company or its subsidiaries or any other individual having a relationship, which, in the opinion of such company’s board of directors, would interfere with the SEC related todirector’s exercise of independent judgment in carrying out the transaction, but haveresponsibilities of a director. Based on business and personal information provided by each director concerning her or his background, employment, and affiliations, including family relationships, the Company’s board of directors has determined that thereeach of Mr. Byrnes, Mr. Ehrlich, Ms. LaPorte, Ms. Rapaport and Dr. Rolfe is an independent director under the Nasdaq listing rules and Rule 10A-3 of the Exchange Act. In addition, the Company determined that each of Brian G. Atwood, Barbara A. Kosacz and Caroline M. Loewy, who served on the board of directors during fiscal year 2023, was also an independent director of PBAX under the Nasdaq listing rules and Rule 10A-3 of the Exchange Act; provided, however, that in connection with Mr. Atwood’s appointment as the Company’s Chief Executive Officer at the Closing, Mr. Atwood is no longer independent.

In addition, the rules of Nasdaq require that, subject to specified exceptions, each member of a listed company’s audit, compensation and nominating and corporate governance committees be independent. Under the rules of Nasdaq, a director will not be sufficient time before January 8, 2023 (the current deadlineonly qualify as an “independent director” if, in the charter for completion an initial business combination)opinion of that company’s board of directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director.  In making these determinations, the Company’s board of directors considered the current and prior relationships that each non-employee director has with the Company and all other facts and circumstances the Company’s board of directors deemed relevant in determining independence, including the beneficial ownership of the Company’s Common Stock by each non-employee director and relationships with each of PBAX and Legacy CERo. In particular, the Board considered Mr. Ehrlich’s service as Chief Executive Officer of PBAX prior to hold a special meeting to obtain the requisite stockholder approval of, and to consummate, the Business Combination. Management believes that it can closeUnder applicable Nasdaq rules, such service as an officer of a special purpose acquisition corporation does not preclude a determination of independence on the Business Combination before April 8, 2023 (i.e., the endboard of directors of the three-month extension period). Accordingly, the Board believes that it is in the best interests of our stockholders to obtain the Extension. Recent changes in U.S. federal tax law may increase our tax liabilities as a result of stockholder redemptions occurring on or after January 1, 2023, including with respect to any redemption of public shares occurring in connection with the Business Combination on or after such date.

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension becomes effective, prior to effecting the Charter Amendment and the Trust Amendment, Phoenix Biotech Sponsor LLC (the “sponsor”) (or one or more of its affiliates, members or third-party designees) (the “Lender”) shall make a deposit into the trust account of the Company (the “Trust Account”) of $325,000. In addition, if the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension becomes effective, in the event that the Company has not consummated the Business Combination by April 8, 2023, without approval of the public stockholders, the Company may, by resolution of the Board if requested by the sponsor, and upon five business days’ advance notice prior to the applicable Termination Date extend the Termination Date up to three times, each by one additional month (for a total of up to three additional months to complete the Business Combination), provided that a Lender will deposit into the Trust Account: (I) for the first such monthly extension, $100,000; (II) for the second such monthly extension, $125,000 and (III) for the third such monthly extension, $150,000, for an aggregate deposit of up to $375,000. If the Company completes the Business Combination, it will, at the option of the Lender, repay the amounts loaned under the promissory note(s) or convert a portion or all of the amounts loaned under such promissory note(s) into units at a price of $10.00 per unit, which units will be identical to the private placement units issued to the Sponsor at the time of the Initial Public Offering. If the Company does not complete the Business Combination by the final applicable Extended Termination Date, such promissory notes will be repaid only from funds held outside of the Trust Account. “Extended Termination Date” means April 8, 2023, or in the case of one or more further extensions of the Termination Date as described above, then May 8, 2023, June 8, 2023 or July 8, 2023, as the case may be.

You are not being asked to vote on any business combination at this time. If the Charter Amendment Proposal and the Trust Amendment Proposal are implemented and you do not elect to redeem your public shares now, you will retain the right to vote the Business Combination when it is submitted to stockholders and the right to redeem your public shares into a pro rata portion of the Trust Account in the eventcombined company following a business combination is approved and completed (as long as your election is made at least two business days prior to the meeting at which the stockholders’ vote is sought) or the Company has not consummated the business combination by the Extended Termination Date.

Holders (“public stockholders”)

Classified Board of the Company’s Class A common stock, par value $0.0001 per share (“public shares”), may elect to redeem their shares for their pro rata portion of the funds available in the Trust Account in connection with the Charter Amendment Proposal (the “Election”) regardless of whether or how such public stockholders vote with respect to the Charter Amendment Proposal. However, the Company will not proceed with the Charter Amendment Proposal or the Trust Amendment Proposal if the redemption of public shares in connection therewith would cause the Company to have net tangible assets of less than $5,000,001. If the Charter Amendment Proposal and Trust Amendment Proposal are approved by the requisite vote of stockholders, the remaining public stockholders will retain their right to redeem their public shares for their pro rata portion of the funds available in the Trust Account when the Business Combination is submitted to the stockholders. Furthermore, if the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension or any additional extension(s) is implemented, then in accordance with the terms of that certain investment management trust agreement, dated as of October 5, 2021, by and between the Company and Continental Stock Transfer & Trust Company (as amended, the “Trust Agreement”), the Trust Account will not be liquidated (other than to effectuate the redemptions) until the earlier of (a) receipt by the Trustee of a termination letter (inDirectors

In accordance with the terms of the Trust Agreement) or (b) the Extended Termination Date.

Any demand for redemption, once made, may be withdrawn at any time until the deadline for exercising redemption requestsCompany’s amended and thereafter, with our consent, until the vote is taken with respect to the Charter Amendment Proposal and the Trust Amendment Proposal. Furthermore, if a holderrestated certificate of a public share delivered its certificate in connection with an election of its redemption and subsequently decides prior to the applicable date not to elect to exercise such rights, it may simply request that the transfer agent return the certificate (physically or electronically).

The withdrawal of funds from the Trust Account in connection with the Election will reduce the amount held in the Trust Account following the redemption, and the amount remaining in the Trust Account may be significantly reduced from the approximately $179.6 million that was in the Trust Account as of September 30, 2022.

If the Charter Amendment Proposal and the Trust Amendment Proposal are not approved and we do not consummate a business combination by January 8, 2023, in accordance with our charter, we will (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account including interest earned on the funds held in the Trust Account and not previously released to the Company to pay franchise and income taxes (less up to $100,000 of the net interest to pay dissolution expenses)incorporation (“Charter”), divided by the number of then outstanding public shares, which redemption will completely extinguish public stockholders’ rights as stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the Company’s remaining stockholders and the Company’s board of directors dissolveis divided into three classes with staggered, three-year terms. At each annual meeting of stockholders, the directors whose terms then expire will be eligible for reelection until the third annual meeting following reelection. The Company’s directors are divided among the three classes as follows:

The Company’s second amended and liquidate, subjectrestated bylaws (“Bylaws”) provide that the number of members of its board of directors shall be fixed in each case toaccordance with the Company’s obligations under Delaware law to provide for claimsCharter. The Company’s Charter provides that the authorized number of creditors and the requirements of other applicable law.

While wedirectors may utilize funds from the Trust Account to pay any potential income or franchise taxes, we will not utilize any funds from our Trust Account to pay any potential excise taxes that may become due upon a redemptionbe changed only by resolution of the public shares, includingboard of directors. Any additional directorships resulting from an increase in connection with a liquidationthe number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of the Company in 2023 if we do not effect a business combination prior to the Termination Date. To the extent there are insufficient funds in our working capital to fund the paymentdirectors. The Company’s board of any potential excise taxes that may become due upon a redemption of public shares in connection with a liquidation of the Company in 2023 if we do not effect a business combination prior to the Termination Date, our Sponsor has agreed to contribute to us (which may be by working capital loan) funds necessary to make any such potential excise tax payment without using proceeds (including interest income) from the Trust Account.

Subject to the foregoing, the affirmative vote ofdirectors is currently fixed at least 65% of the outstanding sharesseven members. The division of the Company’s common stock is required to approve the Charter Amendment Proposal and the Trust Amendment Proposal. Approvalboard of directors into three classes with staggered three-year terms may delay or prevent a change of the Adjournment Proposal requires the affirmative voteCompany’s board of holdersdirectors or a change in control of the majority of the votes cast

by stockholders represented via the remote platform or by proxy at the Special Meeting. Our Board will abandon and not implement the Charter Amendment Proposal or the Trust Amendment Proposal unless our stockholders approve both the Charter Amendment Proposal and the Trust Amendment Proposal. Notwithstanding stockholder approval of the Charter Amendment Proposal and the Trust Amendment Proposal, our Board will retain the right to abandon and not implement the Charter Amendment or Trust Amendment at any time without any further action by our stockholders.

After careful consideration of all relevant factors, the Board of Directors has determined that each of the proposals are advisable and recommends that you vote or give instruction to vote “FOR” such proposals.

Voting Rights and Revocation of Proxies

Only holders of record of our common stock at the close of business on November 10, 2022 (the “Record Date”) are entitled to notice of the Special Meeting and to vote at the Special Meeting and any adjournments or postponements of the Special Meeting.

company. The shares of common stock represented by all validly executed proxies received in time to be taken to the Special Meeting and not previously revoked will be voted at the meeting. This proxyCompany’s directors may be revokedremoved only for cause by the stockholder at any time prior to its being voted by filing with the Secretary of the Company either a notice of revocation or a duly executed proxy bearing a later date. We intend to release this proxy statement and the enclosed proxy card to our stockholders on or about November 22, 2022.

Dissenters’ Right of Appraisal

Holders of shares of our common stock do not have appraisal rights under Delaware law or under the governing documents of the Company in connection with this solicitation.

Outstanding Shares and Quorum

The number of outstanding shares of common stock entitled to vote at the Special Meeting is 22,981,250. Each share of common stock is entitled to one vote. The presence represented by virtual attendance or by proxy at the Special Meeting of the holders of shares, or a majority of the number of outstanding shares of common stock, will constitute a quorum. There is no cumulative voting. Shares that abstain or for which the authority to vote is withheld on certain matters (so-called “broker non-votes”) will be treated as present for quorum purposes on all matters.

Broker Non-Votes

Under the DGCL, shares that are voted “abstain” or “withheld” are counted as present for purposes of determining whether a quorum is present at the Special Meeting. Abstentions and withheld votes will have the same effect as a vote “AGAINST” the Charter Amendment Proposal and the Trust Amendment Proposal, and will have no effect on the Adjournment Proposal.

Because the Proposals are “non-discretionary” items, your broker will not be able to vote uninstructed shares for any of the Proposals. If there are any proposals that are “discretionary” items, then the broker may cast a vote on such proposals, resulting in the shares being counted for purposes of determining whether a quorum is present and a broker “non-vote” is deemed to occur with respect to each “non-discretionary” item. However, since none of the Proposals are “discretionary” items, if you do not provide voting instructions, your shares will not be voted and will not be counted as present for purposes of determining whether a quorum is present.

Required Votes for Proposals

Assuming the presence of a quorum at the Special Meeting, the Proposals presented at the Special Meeting will require the following votes:

Director Attendance at Annual Meeting of Stockholders

The approvalCompany encourages its directors to attend its annual meetings of stockholders. The Company did not hold an annual meeting of stockholders during the fiscal year ended December 31, 2023.

Board and Committee Meetings

During the fiscal year ended December 31, 2023, the Company’s board of directors met four times, its audit committee (the “Audit Committee”) met four times, its compensation committee (the “Compensation Committee”) and the Company’s nominating and corporate governance committee met zero times. Each board member attended 75% or more of the Charter Amendment Proposalaggregate number of meetings of the board of directors and meetings of the Trust Amendment Proposal will requirecommittees on which he or she served during the affirmative votefiscal year ended December 31, 2023, for which he or she was a director or committee member.

Board Leadership Structure

The Company’s board of holdersdirectors does not have a policy regarding separation of at least 65%the roles of all then outstanding sharesChief Executive Officer and Chairman of common stock entitledthe board of directors. The Company’s board of directors recognizes that it is important to vote thereon atdetermine an optimal board leadership structure to ensure the Special Meeting. Accordingly,independent oversight of management as the Company continues to grow, and believes it is in the Company’s best interests to make determinations regarding such leadership structure based on circumstances from time to time. Currently, the Company’s Chief Executive Officer serves as the Chairman of the board of directors.

The Company’s board of directors believes that this leadership structure, combined with the Company’s corporate governance policies and processes, creates an appropriate balance between strong and consistent leadership and independent oversight of its business. The Chairman chairs the meetings of the board of directors and stockholders, with input from the independent directors, and as such, the Company’s board of directors believes that a stockholder’s failureperson with comprehensive knowledge of the Company is in the best position to vote by proxy orserve such role. In making this determination, the board of directors considered, among other matters, Mr. Atwood’s management of the Company’s business on a day-to-day basis coupled with his direct involvement in the Company’s business operations, and believed that Mr. Atwood is highly qualified to vote in person (which would include presence at a virtual meeting) at the Special Meeting or an abstention will have the same effectact as a vote “AGAINST” the Charter Amendment Proposalboth Chairman and the Trust Amendment Proposal.

The cost of preparing, assembling, printing and mailing this proxy statementcorporate governance committee and the accompanying formboard of proxy, and the costdirectors consider a broad range of soliciting proxiesfactors relating to the Special Meeting,qualifications of nominees. The nominating and corporate governance committee’s and the board of directors’ priority in selecting board members is the identification of persons who will be borneprovide a composite mix of backgrounds, experience, knowledge and capabilities that will allow the board of directors to promote the Company’s strategic objectives and fulfill its responsibilities to the Company’s stockholders. The nominating and corporate governance committee and the board of directors highly value diversity and, as such, also consider diversity of gender, race, ethnicity, age, gender identity, gender expression and sexual orientation when selecting members of the Company’s board of directors.

Any stockholder who wishes to recommend a candidate for consideration by the Company.

Some banks and brokers have customers who beneficially own common stock listed of recordcommittee as a nominee for director should follow the procedures described in the namesproxy statement to be filed with the SEC in connection with the Company’s 2024 special meeting of nominees. We intend to request banks and brokers to solicit such customers and will reimburse them for their reasonable out-of-pocket expenses for such solicitations. If any additional solicitationstockholders within 120 days after the end of the holdersfiscal year ended December 31, 2023. The nominating and corporate governance committee will also consider whether to nominate any person proposed by a stockholder in accordance with the provisions of our outstanding common stock is deemed necessary, we (through our directorsthe Company’s Bylaws relating to stockholder nominations.

Compensation Committee Interlocks and officers) anticipate making such solicitation directly.Insider Participation

Delivery

During the fiscal year ended December 31, 2023, Mr. Ehrlich served as the Chief Executive Officer of Proxy Materialsthe Company’s predecessor, PBAX. In connection with the Business Combination, on February 14, 2024, Mr. Ehrlich ceased to Stockholders

Only one copybe an officer of PBAX. Other than Mr. Ehrlich, during the fiscal year ended December 31, 2023 and as of the date of this proxy statement, will be delivered to an address where two or more stockholders reside withnone of the same last name or who otherwise reasonably appear to be members of the same familyCompensation Committee has ever been one of the Company’s officers or employees. None of the Company’s executive officers currently serves, or has served, as a member of the board of directors or Compensation Committee of any entity that has one or more executive officers serving as a member of the Company’s board of directors or Compensation Committee.

Board Diversity

Board diversity and inclusion is critical to the Company’s success. While the Company does not have a formal policy on board of directors diversity, the board of directors is committed to building a board of directors that consists of the optimal mix of skills, expertise, and diversity capable of effectively overseeing the execution of the Company’s business and meeting our evolving needs, with diversity reflecting gender, age, race, ethnicity, background, professional experience and perspectives. The nominating and corporate governance committee considers the value of diversity on the board of directors in evaluating director nominees. Accordingly, the nominating and corporate governance committee’s evaluation of director nominees includes consideration of their ability to contribute to the diversity of personal and professional experiences, opinions, perspectives and backgrounds on the board of directors.

The matrix below provides certain highlights of the composition of the board of directors based on self-identification. Each term used above and in the stockholders’ prior expressmatrix below has the meaning given to it in Nasdaq Listing Rule 5605(f).

Communication with Directors

Any stockholder or implied consent.interested party may communicate with the board of directors, as a whole, or with individual directors on the board of directors, through an established process for stockholder and other interested party communication. For a communication directed to the board of directors as a whole, stockholders and other interested parties may submit a written communication by postal mail to the attention of the Chairman of our board of directors at the following address: CERo Therapeutics Holdings, Inc., 210 Haskins Way, Suite 230, South San Francisco, CA 94080.

We

For a communication directed to an individual director in his capacity as a member of the board of directors, stockholders and other interested parties may send such communication to the attention of the individual director at the following address: CERo Therapeutics Holdings, Inc., c/o Corporate Secretary, 210 Haskins Way, Suite 230, South San Francisco, CA 94080, Attention: Name of Individual Director.

The Company will deliver promptly upon writtenforward by U.S. mail any such communication to each director, and the Chairman of the board of directors in his capacity as a representative of the board of directors, to whom such communication is addressed to the address specified by each such director and the chair of the board of directors, unless there are safety or oral request a separatesecurity concerns that mitigate against further transmission. A copy of this proxy statement. If you share an address with at least one other stockholder, currently receive oneany such written communication may also be forwarded to our general counsel and a copy of our proxy statement atsuch communication may be retained for a reasonable period of time. You may submit your residence,concern anonymously or confidentially.

Communications may be forwarded to other directors if they relate to important substantive matters and would likeinclude suggestions or comments that may be important for other directors to know. In general, communications relating to corporate governance and long-term corporate strategy are more likely to be forwarded than communications relating to ordinary business affairs, personal grievances and matters as to which the Company tends to receive repetitive or duplicative communications.

Code of Business Conduct and Ethics

The Company has adopted a separate copywritten code of business conduct and ethics that applies to the Company’s directors, officers, and employees, including its principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. The code of business conduct and ethics is available under the Investors section of the Company’s website at www.cero.bio/investors. In addition, the Company intends to post on its website all disclosures that are required by law or the listing standards of Nasdaq concerning any amendments to, or waivers from, any provision of the code of business conduct and ethics. The reference to the Company’s website address does not constitute incorporation by reference of the information contained at or available through our proxy statementwebsite. The Company has included its website address as an inactive textual reference only.

Insider Trading Arrangements and Policies

The board of directors has adopted an insider trading policy which governs the purchase, sales, and/or other dispositions of its securities by directors, officers, and employees. The insider trading policy is attached hereto as Exhibit 19 and incorporated herein. In addition, the Company has adopted a Rule 10b5-1 trading plan policy, which permits its officers, directors, and certain other persons to enter into trading plans complying with Rule 10b5-1 under the Exchange Act. Generally, under these trading plans, the individual relinquishes control over the transactions once the trading plan is put into place and can only put such plans into place while the individual is not in possession of material non-public information. Accordingly, sales under these plans may occur at any time, including possibly before, simultaneously with, or immediately after significant events involving the Company.

Policy on Trading, Pledging and Hedging of Company Stock

Certain transactions in the Company’s securities (such as purchases and sales of publicly traded put and call options, and short sales) create a heightened compliance risk or could create the appearance of misalignment between management and stockholders. In addition, securities held in a margin account or pledged as collateral may be sold without consent if the owner fails to meet a margin call or defaults on the loan, thus creating the risk that a sale may occur at a time when an officer or director is aware of material, non-public information or otherwise is not permitted to trade in the Company’s securities. The insider trading policy expressly prohibits derivative transactions of the Company’s stock by its executive officers, directors and employees. In addition, the Company’s insider trading policy also expressly prohibits purchases of any derivative securities that provide the economic equivalent of ownership.

AUDIT COMMITTEE REPORT

The Audit Committee is appointed by the Board to assist the Board in fulfilling its oversight responsibilities with respect to (1) the integrity of the Company’s financial statements and financial reporting process and systems of internal controls regarding finance, accounting, and compliance with legal and regulatory requirements, (2) the qualifications, independence, and performance of the Company’s independent registered public accounting firm, (3) the performance of the Company’s internal audit function, if any, and (4) other matters as set forth in the charter of the Audit Committee approved by the Board.

Management is responsible for future stockholder meetingsthe preparation of the Company’s financial statements and the financial reporting process, including its system of internal control over financial reporting and its disclosure controls and procedures. The independent registered public accounting firm is responsible for performing an audit of the Company’s financial statements in accordance with the standards of the Public Company Accounting Oversight Board, or the PCAOB, and issuing a report thereon. The Audit Committee’s responsibility is to monitor and oversee these processes.

In connection with these responsibilities, the Audit Committee reviewed and discussed with management and the independent registered public accounting firm the audited consolidated financial statements of the Company please specify such request in writingfor the fiscal year ended December 31, 2023. The Audit Committee also discussed with the independent registered public accounting firm the matters required to be discussed by the PCAOB’s Auditing Standard No. 1301, Communication with Audit Committees. In addition, the Audit Committee received written communications from the independent registered public accounting firm confirming their independence as required by the applicable requirements of the PCAOB and send such written requesthas discussed with the independent registered public accounting firm their independence.

Based on the reviews and discussions referred to Phoenix Biotech Acquisition Corp., 2201 Broadway, Suite 705, Oakland, CA 94612, Attention: Secretary; or callabove, the Audit Committee recommended to the Board that the audited consolidated financial statements of the Company promptlybe included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2023 (the “Annual Report”), that was filed with the SEC. The information contained in this report shall not be deemed to be (1) “soliciting material,” (2) “filed” with the SEC, (3) subject to Regulations 14A or 14C of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or (4) subject to the liabilities of Section 18 of the Exchange Act. This report shall not be deemed incorporated by reference into any of the Company’s other filings under the Exchange Act or the Securities Act of 1933, as amended (the “Securities Act”), except to the extent that the Company specifically incorporates it by reference into such filing.

THE AUDIT COMMITTEE OF THE
BOARD OF DIRECTORS OF
CERO THERAPEUTICS HOLDINGS, INC.

Michael Byrnes, Chairperson
Chris Ehrlich
Robyn Rapaport

April 15, 2024

EXECUTIVE COMPENSATION

Except as otherwise specified herein, the information set forth herein relates to the executive compensation paid by Legacy CERo prior to the Business Combination, and agreements with the Company, effective as of the Business Combination. PBAX did not pay any compensation to any of its directors or executive officers at (215) 731-9450.any time from its initial public offering through the completion of the Business Combination. This section discusses the material components of the executive compensation program for the Company’s named executive officers. The Company’s only named executive officer for the fiscal year ended December 31, 2023 was Dr. Corey, as Dr. Corey was the only executive officer during the period presented.

If you share

2023 Summary Compensation Table

None of PBAX’s executive officers received any compensation for services rendered in 2023. The following table presents all of the compensation awarded to the sole named executive officer of Legacy CERo during the years listed below.

Narrative Disclosure to the 2023 Summary Compensation Table

Compensation of the Company’s named executive officer for the fiscal year ended December 31, 2023 was determined and recommended by the Compensation Committee, and approved by the board of directors. The Compensation Committee engaged a compensation consulting firm to provide and structure benchmarking data for similar positions in similar companies.

2023 Base Salaries

The named executive officer’s base salary is a fixed component of annual compensation for performing specific duties and functions. Dr. Corey’s base salary is adjusted from time to time to realign with market levels after taking into account individual responsibilities, performance and experience. For the fiscal year ended December 31, 2023, Dr. Corey’s annual base salary was $360,000.

Perquisites

The Company generally does not provide perquisites to its employees, other than certain de minimis perquisites available to all of the Company’s employees, including its named executive officers. 

401(k) Plan

The Company maintains the CERo Therapeutics 401(k) Plan, a tax-qualified retirement plan that provides eligible employees, including the named executive officer, with an addressopportunity to save for retirement on a tax-advantaged basis. Plan participants are able to defer eligible compensation subject to applicable annual limits under the Code. Participants’ pre-tax or roth contributions are allocated to each participant’s individual account and are then invested in selected investment alternatives according to the participants’ directions. Participants are immediately and fully vested in their contributions. The Company matches each participant’s contribution up to a safe harbor maximum of 4% of his or her eligible compensation with at least one other stockholderparticipants vesting immediately and currently receive multiple copiesfully in such matching contributions. The Company’s 401(k) plan is intended to be qualified under Section 401(a) of our proxy statement,the Code with the 401(k) plan’s related trust intended to be tax exempt under Section 501(a) of the Code.

Health and you would likeWelfare Benefits

The Company provides benefits to receiveits named executive officer on the same basis as provided to all of its employees, including health, dental and vision insurance, as well as life and disability insurance. Legacy CERo did not, and the Company will not, maintain any executive-specific benefit or perquisite programs. Benefits were and are anticipated to be offered on the same basis as provided to all of its employees.

Outstanding Equity Awards as of December 31, 2023

There were no outstanding equity incentive plan awards held by the named executive officer as of December 31, 2023.

Overview of Executive Compensation Program

The Compensation Committee anticipates annually reviewing the compensation of the Company’s employees, including its executive officers. In setting executive base salaries and bonuses and granting equity incentive awards, the Compensation Committee considers compensation for comparable positions in the market, the historical compensation levels of the Company’s executive officers, individual performance as compared to the Company’s expectations and objectives, internal equity, the Company’s desire to motivate its employees to achieve short- and long-term results that are in the best interests of Company stockholders, and a single copylong-term commitment to the Company. The Company intends to target a general competitive position and consider independent third-party benchmark analytics to determine the mix of our proxy statement, please specifycompensation of base salary, bonus and long-term incentives.

The Company engaged the services of an external compensation consultant to advise on executive compensation matters including the Company’s overall compensation program design and collection of market data to inform its compensation programs for the executive officers and members of the board of directors. The compensation for the Company’s executive officers will have the following components: base salary, cash bonus opportunities, equity compensation, employee benefits, and severance protections. Base salaries, employee benefits, and severance protections are designed to attract and retain senior management talent. Annual cash bonuses and equity awards are used to promote performance-based pay that aligns the interests of the named executive officers with the long-term interests of the Company’s stockholders and enhances executive retention.

Employment Arrangements

The Company is party to employment agreements with each of its named executive officers. The arrangements generally provide for at-will employment without any specific term and set forth the named executive officer’s initial base salary, bonus potential, eligibility for employee benefits and severance benefits upon a qualifying termination of employment, subject to such request in writingemployee executing a separation agreement with the Company.

Employment Agreement with Mr. Atwood

On March 26, 2024, the Company entered into an employment agreement with Mr. Atwood, the Company’s Chairman and send such written request to Phoenix Biotech Acquisition Corp., 2201 Broadway, Suite 705, Oakland, CA 94612, Attention: Secretary.

Redemption Rights

Chief Executive Officer the (“Atwood Employment Agreement”). Pursuant to our charter, our public stockholders shall be provided with the opportunityAtwood Employment Agreement, Mr. Atwood is entitled to redeem their public shares upon the approvalan initial annual base salary of the Charter Amendment, at a per-share price, payable in cash, equal$360,000, an initial target annual incentive bonus of 50% of Mr. Atwood’s base salary, an initial equity grant, and general eligibility to the aggregate amount then on depositparticipate in the Trust Account (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for useCompany’s employee benefit plans.

The Atwood Employment Agreement provides that in the event Mr. Atwood’s employment is terminated by the Company to pay franchise and income taxes), dividedwithout “cause” (other than as a result of Mr. Atwood’s death or disability) or by the number of then outstanding public shares (if the redemption of public shares in connection therewith would not cause the Company to have net tangible assets of less than $5,000,001). If your redemption request is properly made and the Charter Amendment is approved, these shares will cease to be outstanding and will represent only the right to receive such amount. For illustrative purposes, based on fundsMr. Atwood with “good reason” (each as defined in the Trust Account of approximately $179.6 million on September 30, 2022, the estimated per-share conversion price would have been approximately $10.26.

In order to exercise your redemption rights, you must:

Continental Stock Transfer & Trust Company

One State Street Plaza, 30^th Floor

New York, New York 10004

Attn: Mark Zimkind

E-mail: mzimkind@continentalstock.com; or

Any demand for redemption, once made, may be withdrawn at any time until the deadline for exercising redemption requests (and submitting shares to the transfer agent) and thereafter, with our consent, until the vote is taken with respect to the Charter Amendment. If you delivered your shares for redemption to our transfer agent and decide within the required timeframe not to exercise your redemption rights, you may request that our transfer agent return the shares. You may make such request by contacting our transfer agent at (917) 262-2373, by email at proxy@continentalstock.com or by writing to the address listed above.

Prior to exercising redemption rights, stockholders should verify the market price of our common stock, as they may receive higher proceeds from the sale of their common stock in the public market than from exercising their redemption rights if the market price per shareevent Mr. Atwood’s employment is higher than the redemption price. We cannot assure you that you will be able to sell your shares of our common stock in the open market, even if the market price per share is higher than the redemption price stated above, as there may not be sufficient liquidity in our common stock when you wish to sell your shares.

If you exercise your redemption rights and the redemption is effectuated, your shares of our common stock will cease to be outstanding and will only represent the right to receive a pro rata share of the aggregate amount on deposit in the Trust Account (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for useterminated by the Company to pay franchise and income taxes). You will no longer own those shares and will have no right to participatewithout “cause” (other than as a result of Mr. Atwood’s death or disability) or by Mr. Atwood for “good reason,” in or have any interest in, the future growtheither case, outside of the Company, if any. YouAtwood Change in Control Period, then, Mr. Atwood will be entitled to receivea lump sum cash for these shares only if you properly and timely request redemption.payment equal to three months of his then-current base salary.

If the Charter Amendment Proposal and the Trust Amendment Proposal are not approved and we do not consummate an initial business combination by January 8, 2023 (subject to the requirements of law), we will be required to dissolve and liquidate our Trust Account by returning the then remaining funds (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for use by, the Company to pay franchise and income taxes) in such account to the public stockholders, and our warrants to purchase common stock will expire worthless.

Holders of outstanding units must separate the underlying public shares and public warrants prior to exercising redemption rights with respect to the public shares.

If you hold units registered in your own name, you must deliver to Continental Stock Transfer & Trust Company written instructions to separate such units into public shares and public warrants. This must be completed far enough in advance so that you may then exercise your redemption rights with respect to the public shares upon the separation of the public shares from the units.

If a broker, dealer, commercial bank, trust company or other nominee holds your units, you must instruct such nominee to separate your units. Your nominee must send written instructions by facsimile to Continental Stock Transfer & Trust Company. Such written instructions must include the number of units to be split and the nominee holding such units. Your nominee must also initiate electronically, using DTC’s deposit withdrawal at custodian (“DWAC”) system, a withdrawal of the relevant units and a deposit of an equal number of public

shares and public warrants. This must be completed far enough in advance to permit your nominee to exercise your redemption rights with respect to the public shares upon the separation of the public shares from the units. While this is typically done electronically the same business day, you should allow at least one full business day to accomplish the separation. If you fail to cause your public shares to be separated in a timely manner, you will likely not be able to exercise your redemption rights.

CERTAIN MATERIAL UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS

FOR STOCKHOLDERS EXERCISING REDEMPTION RIGHTS

The following is a discussion of certain material U.S. federal income tax considerations generally applicable toAtwood Employment Agreement provides that in the redemption of Class A common stock for cash, in connection with an exercise of redemption rightsevent Mr. Atwood’s employment terminate as a result of an Election (collectively, the “Redemption”). This discussion applies onlyMr. Atwood’s death or disability, then, Mr. Atwood will be entitled to sharesaccelerated vesting of Class A common stock that are held as capital assets for U.S. federal income tax purposes (generally, property that is held for investment). This discussion does not describe all50% of the U.S. federal income tax consequences that may be relevant to holders in lightthen-unvested portion of their particular circumstances or status, including:outstanding equity awards.

This discussion is based on the Internal Revenue Code of 1986 (the “Code”), proposed, temporary and final Treasury Regulations promulgated under the Code, and judicial and administrative interpretations thereof, all as of the date hereof. All of the foregoing are subject to change, which change could apply retroactively and could affect the tax considerations described herein. This discussion does not address U.S. federal taxes otherMr. Atwood’s benefits after termination (other than those pertaining to U.S. federal income taxation (such as estate or gift taxes, the alternative minimum tax or the Medicare tax on investment income), nor does it address any aspects of U.S. state or local or non-U.S. taxation.

We have not and do not intend to seek any rulings from the Internal Revenue Service (the “IRS”) regarding the tax consequences described herein. There can be no assurance that the IRS will not take positions inconsistent with the considerations discussed below or that any such positions would not be sustained by a court.

This discussion does not consider the tax treatment of partnerships or other pass-through entities (or any entity or arrangement so characterized for U.S. federal income tax purposes) or persons who hold our securities through such entities. If a partnership (or any entity or arrangement so characterized for U.S. federal income tax

purposes) holds Class A common stock, the tax treatment of such partnership and a person treated as a partner of such partnership will generally depend on the status of the partner and the activities of the partnership. Partnerships holding our securities and persons that are treated as partners of such partnerships should consult their tax advisors as to the particular U.S. federal income tax consequences to them of the transactions described herein.

EACH HOLDER SHOULD CONSULT ITS TAX ADVISOR WITH RESPECT TO THE PARTICULAR TAX CONSEQUENCES TO SUCH HOLDER OF A REDEMPTION OF CLASS A COMMON STOCK, INCLUDING THE EFFECTS OF U.S. FEDERAL, STATE AND LOCAL AND NON-U.S. TAX LAWS.

U.S. Holders

This section applies to you if you are a “U.S. Holder.” A U.S. Holder is a beneficial owner of our shares of our Class A common stock who or that is, for U.S. federal income tax purposes:

Redemption of Class A Common Stock Applicable to U.S. Holders

In the event that a U.S. Holder’s Class A common stock is redeemed pursuant to the Redemption, the treatment of the transaction for U.S. federal income tax purposes will depend on whether the Redemption qualifies as a sale of the Class A common stock under Section 302 of the Code. If the Redemption qualifies as a sale of Class A common stock, the U.S. Holder will be treated as described below under “—Gain or Loss on Sale, Taxable Exchange or Other Taxable Disposition of Class A Common Stock.” If the Redemption does not qualify as a sale of Class A common stock, the U.S. Holder will be treated as receiving a corporate distribution with the tax consequences described below under “—Taxation of Distributions.” Whether the Redemption qualifies for sale treatment will depend largely on the total number of shares of our stock treated as held by the U.S. Holder (including any stock constructively owned by the U.S. Holder as a result of owning warrants) relative to all of our shares outstanding both before and after the Redemption. The Redemption generally will be treated as a sale of Class A common stock (rather than as a corporate distribution) if the Redemption (i) is “substantially disproportionate” with respect to the U.S. Holder, (ii) results in a “complete termination” of the U.S. Holder’s interest in usdeath or (iii) is “not essentially equivalent to a dividend” with respect to the U.S. Holder. These testsdisability) are explained more fully below.

In determining whether any of the foregoing tests are satisfied, a U.S. Holder takes into account not only stock actually owned by the U.S. Holder, but also shares of our stock that are constructively owned by it. A U.S. Holder may constructively own, in addition to stock owned directly, stock owned by certain related individuals and entities in which the U.S. Holder has an interest or that have an interest in such U.S. Holder, as well as any stock the U.S. Holder has a right to acquire by exercise of an option, which would generally include common stock which could be acquired pursuant to the exercise of the warrants. In order to meet the substantially disproportionate test, the percentage of our outstanding voting stock actually and constructively owned by the U.S. Holder immediately following the Redemption must,conditioned, among other requirements, be less than 80%things, on him timely signing and not revoking a general release of the percentage of our outstanding voting stock actually and constructively owned by the U.S. Holder immediately before the Redemption. There will be a complete termination of a U.S. Holder’s interest if either (i) all of the

shares of our stock actually and constructively owned by the U.S. Holder are redeemed or (ii) all of the shares of our stock actually owned by the U.S. Holder are redeemed and the U.S. Holder is eligible to waive, and effectively waives in accordance with specific rules, the attribution of stock owned by certain family members and the U.S. Holder does not constructively own any other stock. The Redemption of the will not be essentially equivalent to a dividend if a U.S. Holder’s conversion results in a “meaningful reduction” of the U.S. Holder’s proportionate interest in us. Whether the Redemption will result in a meaningful reduction in a U.S. Holder’s proportionate interest in us will depend on the particular facts and circumstances. However, the IRS has indicated in a published ruling that even a small reductionclaims in the proportionate interest of a small minority stockholder in a publicly held corporation who exercises no control over corporate affairs may constitute such a “meaningful reduction.” A U.S. Holder should consult with its own tax advisors as toCompany’s favor.

The payments and benefits under the tax consequences of the Redemption.

If none of the foregoing tests is satisfied, then the Redemption will be treated as a corporate distribution and the tax effects will be as described below under “—Taxation of Distributions.” After the application of those rules, any remaining tax basis of the U.S. Holder in the redeemed Class A common stock will be added to the U.S. Holder’s adjusted tax basis in its remaining stock, or, if it has none, to the U.S. Holder’s adjusted tax basis in its warrants or possibly in other stock constructively owned by it.

Taxation of Distributions

If a U.S. Holder’s redemption of shares of Class A common stockAtwood Employment Agreement in connection with the Redemption is treated as a distribution, such distributions will generally constitute a dividendchange in control may not be eligible for U.S. federal income tax purposesdeduction by us pursuant to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Distributions in excess of current and accumulated earnings and profits will constitute a return of capital that will be applied against and reduce (but not below zero) the U.S. Holder’s adjusted tax basis in our Class A common stock. Any remaining excess will be treated as gain realized on the sale or other dispositionSection 280G of the Class A common stockCode. These payments and will be treated as described below under the section entitled “—Gain or Loss on Sale, Taxable Exchange or Other Taxable Disposition of Common Stock.”

Dividends received by a U.S. Holder that is a taxable corporation will generally qualify for the dividends received deduction if the requisite holding period is satisfied. With certain exceptions (including, but not limited to, dividends treated as investment income for purposes of investment interest deduction limitations), and provided certain holding period requirements are met, dividends received by a non-corporate U.S. Holder will generally constitute “qualified dividends” that will be subject to tax at the maximum tax rate applicable to long-term capital gains.

Gain or Loss on Sale, Taxable Exchange or Other Taxable Disposition of Class A Common Stock

If a U.S. Holder’s redemption of shares of Class A common stock in connection with the Redemption is treated as a sale or other taxable disposition, a U.S. Holder will generally recognize capital gain or loss in an amount equal to the difference between the amount realized and the U.S. Holder’s adjusted tax basis in the shares of Class A common stock redeemed. Any such capital gain or loss will generally be long-term capital gain or loss if the U.S. Holder’s holding period for the Class A common stock so disposed of exceeds one year. Long-term capital gains recognized by non-corporate U.S. Holders will be eligible to be taxed at reduced rates. The deductibility of capital losses is subject to limitations.

Generally, the amount of gain or loss recognized by a U.S. Holder is an amount equal to the difference between (i) the sum of the amount of cash and the fair market value of any property received in such disposition and (ii) the U.S. Holder’s adjusted tax basis in its Class A common stock so disposed of. A U.S. Holder’s adjusted tax basis in its Class A common stock will generally equal the U.S. Holder’s acquisition cost less any prior distributions paid to such U.S. Holder with respect to its shares of Class A common stock treated as a return of capital. If the holder purchased an investment unit consisting of both shares and warrants, the cost of such unit

must be allocated between the shares and warrants that comprised such unit based on their relative fair market values at the time of the purchase. Calculation of gain or loss must be made separately for each block of shares owned by a U.S. Holder. Any U.S. Holder who has tendered all of his actually owned shares for the Redemption but continues to hold warrants after the Redemption will generally not be considered to have experienced a complete termination of his interest in the Company.

Non-U.S. Holders

This section applies to you if you are a “Non-U.S. Holder.” A Non-U.S. Holder is a beneficial owner of our Class A common stock who or that is, for U.S. federal income tax purposes:

but does not include an individual who is present in the United States for a period or periods aggregating 183 days or more in the taxable year of disposition. If you are such an individual, you should consult your tax advisor regarding the U.S. federal income tax consequences of the Redemption.

Redemption of Class A Common Stock Applicable to U.S. Holders

The characterization for U.S. federal income tax purposes of the redemption of a Non-U.S. Holder’s Class A common stock pursuant to the Redemption generally will correspond to the U.S. federal income tax characterization of such a redemption of a U.S. Holder’s Class A common stock, as described under “—U.S. Holders—Redemption of Class A Common Stock Applicable to U.S. Holders” above, and the consequences of the Redemption to the Non-U.S. Holder will be as described below under “—Taxation of Distributions” and “—Gain on Sale, Taxable Exchange or Other Taxable Disposition of Class A Common Stock,” as applicable.

Taxation of Distributions

If a Non-U.S. Holder’s redemption of shares of Class A common stock pursuant to the Redemption is treated as a distribution, to the extent paid out of our current or accumulated earnings and profits (as determined under U.S. federal income tax principles), such distribution will constitute a dividend for U.S. federal income tax purposes and, provided such dividend is not effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States, we will be required to withhold tax from the gross amount of the dividend at a rate of thirty percent (30%), unless such Non-U.S. Holder is eligible for a reduced rate of withholding tax under an applicable income tax treaty and timely provides proper certification of its eligibility for such reduced rate (usually on an IRS Form W-8BEN or W-8BEN-E). Any distribution not constituting a dividend will be treated first as reducing (but not below zero) the Non-U.S. Holder’s adjusted tax basis in its shares of our Class A common stock and, to the extent such distribution exceeds the Non-U.S. Holder’s adjusted tax basis, as gain realized from the sale or other disposition of the Class A common stock, which will be treated as described below under the section entitled “—Gain on Sale, Taxable Exchange or Other Taxable Disposition of Class A Common Stock.”

The withholding tax described above does not apply to a dividend paid to a Non-U.S. Holder who provides an IRS Form W-8ECI, certifying that such dividend is effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States. Instead, the effectively connected dividend will be subject to regular U.S. federal income tax as if the Non-U.S. Holder were a U.S. Holder, subject to an applicable income tax treaty providing otherwise. A Non-U.S. Holder that is a corporation for U.S. federal income tax purposes and is receiving effectively connected dividendsbenefits may also be subject to an additional “branch profits tax” imposed atexcise tax under Section 4999 of the Code. If the payments or benefits payable to Mr. Atwood in connection with a rate of thirty percent (30%) (or a lower applicable treaty rate).

Gain on Sale, Taxable Exchange or Other Taxable Disposition of Common Stock

If a Non-U.S. Holder’s redemption of shares of Class A common stock pursuant to the Redemption is treated as a sale or other taxable disposition,change in control would be subject to the discussionsexcise tax imposed under Section 4999 of FATCA and backup withholding, belowthe Code, then those payments or benefits will be reduced if such reduction would result in a Non-U.S. Holder will generally not be subjecthigher net after-tax benefit to U.S. federal income or withholding tax in respect of gain recognized on a sale, taxable exchange or other taxable disposition of our Class A common stock, unless:him.

PROPOSAL 1: THE CHARTER AMENDMENT PROPOSAL

The proposed Charter Amendment would amend the Company’s charter to (a) extend the date by which the Company has to consummate an initial business combination for an additional three months, from January 8, 2023 to April 8, 2023 (such date, as so extended, the “Termination Date”), (b) provide the Board the ability to further extend the date by which the Company has to consummate an initial business combination up to three additional times for one month each time, for a maximum of six additional months. “Extended Termination Date” means April 8, 2023, or in the case of one or more further extensions of the Termination Date as described above, then May 8, 2023, June 8, 2023 or July 8, 2023, as the case may be. As with potential redemptions in connection with an initial business combination, the Charter Amendment would restrict redemption rights in connection with any further amendment of the charter with respect to 20% or more of our public shares. The complete text of the proposed Charter Amendment is attached to this proxy statement as Annex A. All stockholders are encouraged to read the proposed Charter Amendment in its entirety for a more complete description of its terms.

Reasons for the Proposed Charter Amendment

The Charter Amendment Proposal and the Trust Amendment Proposal are essential to the overall implementation of the Board’s plan to extend the business combination period as contemplated by Charter Amendment Proposal and the Trust Amendment Proposal (the “Extension”). The purpose of the Charter Amendment Proposal, the Trust Amendment Proposal and, if necessary, the Adjournment Proposal, is to allow us additional time to finalize the terms and consummate the Business Combination.

As previously announced, we entered into a Business Combination Agreement dated October 30, 2022 (the “Business Combination Agreement,” and together with the other agreements and transactions contemplated by the Business Combination Agreement, the “Business Combination”), with Intrinsic Medicine, Inc., a Delaware corporation (“Intrinsic”), and OM Merger Sub, Inc., a Delaware corporation and a wholly-owned subsidiary of PBAX (“Merger Sub”), pursuant to which Merger Sub will merge with and into Intrinsic, with Intrinsic surviving as a wholly-owned subsidiary of PBAX. In connection with the consummation of the Business Combination, we will change our corporate name to “Intrinsic Medicine, Inc.” The Board has unanimously (i) approved and declared advisable the Business Combination Agreement, the Business Combination and the other transactions contemplated thereby, and (ii) resolved to recommend approval of the Business Combination Agreement and related matters by our stockholders. We will hold a meeting of stockholders to consider and approve the proposed Business Combination, and a proxy statement/prospectus will be sent to all of our stockholders of record.

We and the other parties to the Business Combination Agreement are currently working towards satisfaction of the conditions to completion of the Business Combination, including drafting the necessary filings with the SEC related to the transaction, but have determined that there will not be sufficient time before January 8, 2023 (the current deadline in the charter for completion an initial business combination) to hold a special meeting to obtain the requisite stockholder approval of, and to consummate, the Business Combination. Management believes that it can close the Business Combination before April 8, 2023 (i.e., the end of the three-month extension period). Accordingly, the Board believes that it is in the best interests of our stockholders to obtain the Extension. However, recent changes in U.S. federal tax law which may increase our tax liabilities as a result of stockholder redemptions occurring on or after January 1, 2023, including with respect to any redemption of public shares occurring in connection with the Business Combination on or after such date.

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved and the Extension becomes effective, prior to effecting the Charter Amendment and the Trust Amendment, Phoenix Biotech Sponsor LLC (the “sponsor”) (or one or more of its affiliates, members or third-party designees) (the “Lender”) shall make a deposit into the trust account of the Company (the “Trust Account”) of $325,000. In addition, if the Charter

Amendment Proposal and the Trust Amendment Proposal are approved and the Extension becomes effective, in the event that the Company has not consummated the Business Combination by April 8, 2023, without approval of the public stockholders, the Company may, by resolution of the Board if requested by the sponsor, andCommon Stock issuable upon five business days’ advance notice prior to the applicable Termination Date extend the Termination Date up to three times, each by one additional month (for a total of up to three additional months to complete the Business Combination), provided that a Lender will deposit into the Trust Account: (I) for the first such monthly extension, $100,000; (II) for the second such monthly extension, $125,000 and (III) for the third such monthly extension, $150,000, for an aggregate deposit of up to $375,000. If the Company completes the Business Combination, it will, at the option of the Lender, repay the amounts loaned under the promissory note(s) or convert a portion or all of the amounts loaned under such promissory note(s) into units at a price of $10.00 per unit, which units will be identical to the private placement units issued to the Sponsor at the time of the Initial Public Offering. If the Company does not complete the Business Combination by the final applicable Extended Termination Date, such promissory notes will be repaid only from funds held outside of the Trust Account. “Extended Termination Date” means April 8, 2023, or in the case of one or more further extensions of the Termination Date as described above, then May 8, 2023, June 8, 2023 or July 8, 2023, as the case may be.

If the Charter Amendment Proposal and the Trust Amendment Proposal are both approved and the Extension is implemented, then in accordance with the terms of the Trust Agreement, the Trust Account will not be liquidated (other than to effectuate the redemptions) until the earlier of (a) receipt by the Trustee of a termination letter (in accordance with the terms of the Trust Agreement) or (b) the Extended Termination Date.

In order to mitigate the risk of us being deemed to have been operating as an unregistered investment company (including under the subjective test of Section 3(a)(1)(A) of the 1940 Act), we expect that, on or prior to October 5, 2023, if the Termination Date has been extended through that date (which is not permitted by the Extension and, therefore, would require approval by our stockholders at a future date) and we have not yet completed an initial Business Combination, then we will instruct Continental, the trustee with respect to the Trust Account, to liquidate the U.S. government treasury obligations or money market funds held in the Trust Account and thereafter to hold all funds in the Trust Account in cash until the earlier of consummation of our initial Business Combination or liquidation. As a result, following such liquidation, we will likely receive minimal interest, if any, on the funds held in the Trust Account, which would reduce the dollar amount our public shareholders would receive upon any redemption or liquidation of the Company.

If the Charter Amendment Proposal and the Trust Amendment Proposal are not approved and we have not consummated a business combination by January 8, 2023, we will (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account including interest earned on the funds held in the Trust Account (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for use by, the Company to pay franchise and income taxes), divided by the number of then outstanding public shares, which redemption will completely extinguish public stockholders’ rights as stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the Company’s remaining stockholders and the Board, dissolve and liquidate, subject in each case to the Company’s obligations under Delaware law to provide for claims of creditors and the requirements of other applicable law. There will be no distribution from the Trust Account with respect to our warrants which will expire worthless in the event we wind up.

While we may utilize funds from the Trust Account to pay any potential income or franchise taxes, we will not utilize any funds from our Trust Account to pay any potential excise taxes that may become due upon a redemption of the public shares, including in connection with a liquidation of the Company in 2023 if we do not effect a business combination prior to the Termination Date. To the extent there are insufficient funds in our working capital to fund the payment of any potential excise taxes that may become due upon a redemption of public shares in connection with a liquidation of the Company in 2023 if we do not effect a business combination

prior to the Termination Date, our Sponsor has agreed to contribute to us (which may be by working capital loan) funds necessary to make any such potential excise tax payment without using proceeds (including interest income) from the Trust Account.

The sponsor is not controlled by, nor does it have substantial ties with a non-U.S. person. We do not expect the Company or the sponsor to be considered a “foreign person” under the regulations administered by the Committee on Foreign Investment in the United States (“CFIUS”).

You are not being asked to vote on any business combination at this time. If the Charter Amendment and Trust Amendment are implemented and you do not elect to redeem your public shares now, you will retain the right to vote the Business Combination when it is submitted to stockholders and the right to redeem your public shares into a pro rata portion of the Trust Account in the event a business combination is approved (as long as your election is made at least two business days prior to the meeting at which the stockholders’ vote is sought) and completed or the Company has not consummated the business combination by the Extended Termination Date.

In connection with the Charter Amendment Proposal and the Trust Amendment Proposal, public stockholders may elect (the “Election”) to redeem their shares for a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest not previously released to us to pay franchise and income taxes, divided by the number of then outstanding public shares, regardless of whether such public stockholders vote “FOR” or “AGAINST” the Charter Amendment Proposal or the Trust Amendment Proposal, and an Election can also be made by public stockholders who do not vote, or do not instruct their broker or bank how to vote, at the Special Meeting. Public stockholders may make an Election regardless of whether such public stockholders were holders as of the Record Date. If the Charter Amendment Proposal, the Trust Amendment Proposal and the Adjournment Proposal are approved by the requisite vote of stockholders, the remaining holders of public shares will retain their right to redeem their public shares when the proposed business combination is submitted to the stockholders, subject to any limitations set forth in our charter, as amended by the Charter Amendment (as long as their election is made at least two business days prior to the meeting at which the stockholders’ vote is sought). However, we will not proceed with the Charter Amendment if the redemption of public shares in connection therewith would cause us to have net tangible assets of less than $5,000,001. Each redemption of shares by our public stockholders will decrease the amount in our Trust Account, which held approximately $179.6 million of marketable securities as of September 30, 2022. In addition, public stockholders who do not make the Election would be entitled to have their shares redeemed for cash if we have not completed a business combination by the applicable Extended Termination Date. Our sponsor, our officers and directors and our other initial stockholders own an aggregate of 5,296,246 shares of our common stock.

To exercise your redemption rights, you must tender your shares to the Company’s transfer agent at least two business days prior to the Special Meeting (or December 14, 2022). You may tender your shares by either delivering your share certificate to the transfer agent or by delivering your shares electronically using DTC’S DWAC system. If you hold your shares in street name, you will need to instruct your bank, broker or other nominee to withdraw the shares from your account in order to exercise your redemption rights. The redemption rights include the requirement that a stockholder must identify itself in writing as a beneficial holder and provide its legal name, phone number, and address in order to validly redeem its public shares.

Interests of our Sponsor, Directors and Executive Officers

When you consider the recommendation of our Board, you should keep in mind that the Company’s executive officers and directors, and their affiliates, have interests that may be different from, or in addition to, your interests as a stockholder. These interests include, among other things:

PROPOSAL 1: RATIFICATION OF APPOINTMENT OF WOLF & COMPANY, P.C. AS THE COMPANY’S INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR 2024

Overview

The Audit Committee has appointed and engaged Wolf to serve as the Company’s independent registered public accounting firm to audit the consolidated financial statements of the Company and the Company’s subsidiary for the 2024 fiscal year, and to perform audit-related services. Wolf has served as Legacy CERo’s independent registered public accounting firm since 2023.

Stockholders are hereby asked to ratify the Audit Committee’s appointment of Wolf as the Company’s independent registered public accounting firm for the 2024 fiscal year.

The Audit Committee is solely responsible for selecting the Company’s independent auditors. Although stockholder ratification of the appointment of Wolf to serve as the Company’s independent registered public accounting firm is not required by law or the Company’s organizational documents, the Board has determined that it is desirable to seek stockholder ratification as a matter of good corporate governance in view of the critical role played by independent registered public accounting firms in maintaining the integrity of financial controls and reporting. If the stockholders do not ratify the appointment of Wolf, the Audit Committee will reconsider its selection and whether to engage an alternative independent registered public accounting firm.

Representatives of Wolf are expected to virtually attend the Special Meeting where they will be available to respond to appropriate questions and, if they desire, to make a statement.

Independent Registered Public Accounting Firm Fees

PBAX’s independent public accounting firm is Citrin Cooperman & Company, LLP (“Citrin”), New York, New York (PCAOB Auditor ID: 02468). Citrin has acted as PBAX’s independent registered public accounting firm since June 8, 2021 (inception). The following table sets forth the aggregate fees and expenses billed to the Company (then known as PBAX, the same legal entity as the Company) by Citrin for fiscal years 2023 and 2022:

Vote Required for Approval

The affirmative vote of holders of at least 65% of the outstanding shares of our common stock is required to approve the Charter Amendment Proposal. If the Charter Amendment Proposal is not approved, the Charter Amendment will not be implemented. Each of the Charter Amendment Proposal and the Trust Amendment Proposal is cross-conditioned on the approval of each other. Broker non-votes, abstentions or the failure to vote on the Charter Amendment Proposal will have the same effect as a vote “AGAINST” the Charter Amendment Proposal.

Each of the Charter Amendment Proposal and the Trust Amendment Proposal is cross-conditioned on the approval of each other. Our Board will abandon and not implement the Charter Amendment Proposal unless our stockholders approve both the Charter Amendment Proposal and the Trust Amendment Proposal. This means that

if one proposal is approved by the stockholders and the other proposal is not, neither proposal will take effect. Notwithstanding stockholder approval of the Charter Amendment Proposal and Trust Amendment Proposal, our Board will retain the right to abandon and not implement the Charter Amendment and Trust Amendment at any time without any further action by our stockholders.

You are not being asked to vote on any business combination at this time. If the Charter Amendment and Trust Amendment are implemented and you do not elect to redeem your public shares now, you will retain the right to vote on the Business Combination when it is submitted to stockholders and the right to redeem your public shares into a pro rata portion of the Trust Account in the event a business combination is approved (as long as your election is made at least two business days prior to the meeting at which the stockholders’ vote is sought) and completed or the Company has not consummated the business combination by the Extended Termination Date.

Recommendation of the Board

OUR BOARD UNANIMOUSLY RECOMMENDS THAT OUR STOCKHOLDERS VOTE “FOR” THE CHARTER AMENDMENT.

PROPOSAL 2: THE TRUST AMENDMENT PROPOSAL

The Trust Amendment

The proposed Trust Amendment would amend our Trust Agreement to allow the Company to extend the business combination period from January 8, 2023 to April 8, 2023 and up to three times for an additional one month each time from April 8, 2023 to May 8, 2023, June 8, 2023 or July 8, 2023 (the “Trust Amendment”). A copy of the proposed Trust Amendment is attached to this proxy statement as Annex B. All stockholders are encouraged to read the proposed Trust Amendment in its entirety for a more complete description of its terms.

Reasonsfees for the Trust Amendmentservices performed to date.

The current Trust Agreement provides that the Company has until 15 months after the closing of the Initial Public Offering. The purpose of the Trust Amendment is to amend the Trust Agreement to extend the liquidation of the Trust Account to the Extended Termination Date if the Charter Amendment is approved. The Trust Amendment is necessary in conjunction with the Charter Amendment because, otherwise, the Trust Agreement would terminate and the result would be the same as if the Charter Amendment was not approved.

If the Trust Amendment is not approved and we do not consummate an initial business combination by January 8, 2023 (subject to the requirements of law), we will be required to dissolve and liquidate our Trust Account by returning the then remaining funds (less $100,000 of net interest to pay potential dissolution expenses (as applicable) and less any other interest released to, or reserved for use by, the Company to pay franchise and income taxes) in such account to the public stockholders, and our warrants to purchase common stock will expire worthless.

If the Trust Amendment is Approved

If the Charter Amendment Proposal and the Trust Amendment Proposal are approved, the amendment to the Trust Agreement in the form of Annex B hereto will be executed and the Trust Account will not be disbursed except in connection with our completion of an initial business combination or in connection with our liquidation if we do not complete an initial business combination by the applicable termination date. The Company will continue to attempt to consummate a business combination until the applicable Extended Termination Date or until the Board determines in its sole discretion that it will not be able to consummate an initial business combination by the applicable Extended Termination Date and does not wish to seek an additional extension.

Vote Required for ApprovalRequired; Board Recommendation

The affirmative vote of holders of at least 65% of the outstanding shares of our common stock is required to approve the Trust Amendment Proposal. If the Trust Amendment Proposal is not approved, the Trust Amendment will not be implemented. Broker non-votes, abstentions or the failure to vote on the Trust Amendment Proposal will have the same effect as a vote “AGAINST” the Trust Amendment Proposal.

Each of the Charter Amendment Proposal and the Trust Amendment Proposal is cross-conditioned on the approval of each other. Our Board will abandon and not implement the Trust Amendment Proposal unless our stockholders approve both the Charter Amendment Proposal and the Trust Amendment Proposal. This means that if one proposal is approved by the stockholders and the other proposal is not, neither proposal will take effect. Notwithstanding stockholder approval of the Charter Amendment Proposal and Trust Amendment Proposal, our Board will retain the right to abandon and not implement the Charter Amendment and Trust Amendment at any time without any further action by our stockholders.

You are not being asked to vote on any business combination at this time. If the Trust Amendment is implemented and you do not elect to redeem your public shares now, you will retain the right to vote on a

proposed business combination when it is submitted to stockholders and the right to redeem your public shares into a pro rata portion of the Trust Account in the event a business combination is approved and completed (as long as your election is made at least two business days prior to the meeting at which the stockholders’ vote is sought) or the Company has not consummated the business combination by the Extended Termination Date.

Recommendation of the Board

OUR BOARD UNANIMOUSLY RECOMMENDS THAT OUR STOCKHOLDERS VOTE “FOR” THE TRUST AMENDMENT PROPOSAL.

PROPOSAL 3: THE ADJOURNMENT PROPOSAL

The Adjournment Proposal, if adopted, will allow our Board to adjourn the Special Meeting to a later date or dates to permit further solicitation of proxies. The Adjournment Proposal will only be presented to our stockholders in the event that there are insufficient votes for, or otherwise in connection with, the approval of the Charter Amendment Proposal and the Trust Amendment Proposal.

Consequences if the Adjournment Proposal is Not Approved

In addition to an adjournment of the Special Meeting upon the approval of the Adjournment Proposal, the chairman of the Special Meeting is empowered under the bylaws to postpone the Special Meeting at any time. In such event, we will issue a press release and take such other steps as it believes are necessary and practical in the circumstances to inform its stockholders of the postponement.

If the Adjournment Proposal is presented at the Special Meeting and is not approved by the stockholders, the chairman of the Special Meeting may not be able to adjourn the Special Meeting to a later date in the event that there are insufficient votes for, or otherwise in connection with, the approval of the Charter Amendment Proposal and the Trust Amendment Proposal.

Vote Required for Approval

The approval of the Adjournment Proposal requires the affirmative vote of the holders of a majority of the issued and outstanding shares of common stockvotes cast in respect of the Adjournment Proposal and entitled to vote thereon at the Special Meeting. Accordingly, if a valid quorum is otherwise established, a stockholder’s failureMeeting will be required to vote by proxy or online at the Special Meetingapprove this proposal. Abstentions and broker non-votes will have no effect on the outcome of any votethis proposal.

PROPOSAL 2: APPROVAL OF THE ISSUANCE OF SHARES OF COMMON STOCK, IN ACCORDANCE WITH NASDAQ LISTING RULE 5635, UPON (I) THE CONVERSION OF THE SERIES A PREFERRED STOCK, (II) THE CONVERSION OF THE SERIES B PREFERRED STOCK, (III) THE EXERCISE OF COMMON WARRANTS AND (IV) THE EXERCISE OF PREFERRED WARRANTS AND CONVERSION OF THE UNDERLYING SERIES A PREFERRED STOCK

Overview

As described in more detail below, in February 2024 and March 2024, the Company issued an aggregate of 10,080 shares of Series A convertible preferred stock, par value $0.0001 per share (“Series A Preferred Stock”), of the Company, 626 shares of Series B convertible preferred stock, par value $0.0001 per share (“Series B Preferred Stock”), warrants to purchase 612,746 shares of Common Stock (the “Common Warrants”) and warrants to purchase 2,500 shares of Series A Preferred Stock (the “Preferred Warrants” and, together with the Common Warrants, the “PIPE Warrants”) in the Private Placement (as defined below).

The Common Stock is listed on the Adjournment Proposal. AbstentionsNasdaq Global Market, and, as such, the Company is subject to the applicable rules of the Nasdaq Stock Market LLC (“Nasdaq”), including Nasdaq Listing Rules 5635(b) and 5635(d). Nasdaq Listing Rule 5635(b) requires the Company to obtain stockholder approval prior to certain issuances with respect to Common Stock or securities convertible into Common Stock which could result in a change of control of the issuer. Generally, Nasdaq interpretations provide that the acquisition of 20% of the shares of an issuer by one person or group of affiliated persons may be considered a change of control of such issuer. Nasdaq Listing Rule 5635(d) requires the Company to obtain stockholder approval prior to certain issuances with respect to Common Stock or securities convertible into Common Stock other than in a public offering if the price is below the “Minimum Price” (as determined in accordance with Nasdaq rules) in an amount greater than or equal to 20% of the number of shares of Common Stock outstanding prior to such issuance, regardless of whether such shares are issued to one person or group or are more widely distributed. The issuance of Common Stock upon the conversion of the Series A Preferred Stock and Series B Preferred Stock, including the Series A Preferred Stock issuable upon exercise of the Preferred Warrants (collectively, the “Preferred Shares”), and upon the exercise of the PIPE Warrants, may result in certain investors in the Private Placement (the “Investors”) acquiring more than 20% of the amount of Common Stock issued and outstanding prior to the Private Placement. Accordingly, the Company needs stockholder approval of the issuance of shares of Common Stock in excess of 20% of the shares of Common Stock outstanding to complete the conversion of the Preferred Shares and the exercise of the PIPE Warrants.

Assuming the issuance of all shares of Common Stock upon conversion of the Series A Preferred Stock and Series B Preferred Stock and upon the exercise of all of the PIPE Warrants, the Investors would own approximately 2.0 million shares of Common Stock, assuming conversion at the initial conversion price of $10.00 per share and exercise price of $9.20 per warrant. Such shares would constitute approximately 11.7% of the outstanding Common Stock. Because the conversion price of the Series A Preferred Stock and Series B Preferred Stock and the exercise price of the PIPE Warrants may be adjusted, the number of shares that will actually be issued may be more or less than such number of shares. In addition, under the terms of the Series A Preferred Stock and Series B Preferred Stock and the Common Warrants, an Investor may not convert the Series A Preferred Stock and Series B Preferred Stock or exercise the Common Warrants to the extent (but only to the extent) such Investor or any of its affiliates would beneficially own a number of shares of Common Stock which would exceed 4.99%, or, at the election of the Investor, a number of shares of Common Stock which would exceed 9.99%.

Private Placement

In February 2024, the Company consummated the first tranche of a private placement of 10,080 shares of Series A Preferred Stock, 612,746 Common Warrants and 2,500 Preferred Warrants, pursuant to the Amended and Restated Securities Purchase Agreement, dated February 14, 2024, by and among PBAX, Legacy CERo and certain Investors for aggregate cash proceeds to the Company of approximately $10.0 million. On April 1, 2024, the Company consummated the second tranche of a private placement of 626 shares of Series B Preferred Stock, pursuant to the Securities Purchase Agreement, dated March 28, 2024, by and among the Company and certain Investors for aggregate cash proceeds to the Company of approximately $0.5 million. A portion of such Series A Preferred Stock and Series B Preferred Stock were issued as consideration for the cancellation of outstanding indebtedness or securities of PBAX or Legacy CERo, including a promissory note of PBAX and certain convertible bridge notes of Legacy CERo. The Company refers to such transactions collectively as the “Private Placement.”

Description of Securities

See “Description of Capital Stock” for a description of the Series A Preferred Stock, Series B Preferred Stock, Preferred Warrants and Common Warrants.

Impact on Stockholders of Approval or Disapproval of this Proposal

If this proposal is approved, existing stockholders will suffer dilution in ownership interests and voting rights as a result of the issuance of shares of Common Stock upon the conversion of the shares of Series A Preferred Stock and Series B Preferred Stock and upon the exercise of the PIPE Warrants. Assuming the issuance of all shares of Common Stock upon conversion of the Series A Preferred Stock and Series B Preferred Stock and upon the exercise of all of the PIPE Warrants, the Investors would own approximately 2.0 million shares of Common Stock, assuming conversion at the initial conversion price of $10.00 per share and exercise price of $9.20 per warrant. Such shares would constitute approximately 11.7% of the Common Stock. Because the conversion price of the Series A Preferred Stock and Series B Preferred Stock and the exercise price of the PIPE Warrants may be adjusted, the number of shares that will actually be issued may be more or less than such number of shares. The ownership interest of the existing stockholders (other than the Investors) would be correspondingly reduced. The number of shares of Common Stock described above does not give effect to (i) the potential future issuance of additional shares of Common Stock due to potential future anti-dilution adjustments on the Series A Preferred Stock, Series B Preferred Stock or PIPE Warrants, (ii) the potential future issuance of shares of Common Stock pursuant to the Committed Equity Financings, (iii) the potential future issuance of shares of Common Stock pursuant to other outstanding options and warrants, or (iv) any other potential future issuances of Common Stock. The sale into the public market of these shares also could materially and adversely affect the market price of the Common Stock.

If this proposal is approved, the issuance of the Common Stock could have an anti-takeover effect because such issuance would make it more difficult for, or discourage an attempt by, a party to obtain control of the Company by tender offer or other means. The issuance of the Common Stock will increase the number of shares entitled to vote, increase the number of votes required to approve a change of control of the Company, and dilute the interest of a party attempting to obtain control of the Company. The Board does not have any current knowledge of any effort by any third party to accumulate the Company’s securities or obtain control of the Company by any means.

If this proposal is not approved, the Investors will not be able to vote or convert their shares of Series A Preferred Stock and Series B Preferred Stock or exercise the PIPE Warrants in excess of 20% of the amount of Common Stock issued and outstanding prior to the Private Placement. Additionally, if stockholders do not approve this proposal at the Special Meeting, the Company must also include a proposal to approve this proposal at a subsequent meeting of stockholders to be held on or prior to July 23, 2024. In the event that stockholder approval is not obtained at such subsequent meeting, the Company must cause additional meetings of stockholders to be held semi-annually thereafter until such approval is obtained. The Company would bear the costs associated with including this proposal for stockholder approval at subsequent stockholder meetings.

Vote Required; Board Recommendation

The affirmative vote of the holders of a majority of the votes cast at the Special Meeting will be counted in connection with the determination of whether a valid quorum is established butrequired to approve this proposal. Abstentions and broker non-votes will have no effect on the outcome of this proposal.

PROPOSAL 3: APPROVAL OF THE ISSUANCE OF SHARES OF COMMON STOCK, IN ACCORDANCE WITH NASDAQ LISTING RULE 5635, PURSUANT TO THE COMMITTED EQUITY FINANCINGS

Overview

As described in more detail below, in February 2024, the Adjournment Proposal.Company entered into: (i) a Common Stock Purchase Agreement (the “Keystone Purchase Agreement”), dated as of February 14, 2024, by and between the Company and Keystone Capital Partners, LLC (“Keystone”), establishing an equity line of credit (the “Keystone Equity Financing”) and (ii) a Purchase Agreement (the “Arena Purchase Agreement” and, together with the Keystone Purchase Agreement, the “Purchase Agreements”), dated as of February 23, 2024, by and between the Company and Arena Business Solutions Global SPC II, Ltd on behalf of and for the account of Segregated Portfolio #13 – SPC #13 (“Arena”), establishing an equity line of credit (the “Arena Equity Financing” and, together, the “Committed Equity Financings”), pursuant to which the Company may sell shares of common stock to Keystone and Arena from time to time in its discretion.

Recommendation

The Common Stock is listed on the Nasdaq Global Market, and, as such, the Company is subject to the applicable rules of the BoardNasdaq, including Nasdaq Listing Rule 5635(d). Nasdaq Listing Rule 5635(d) requires stockholder approval of transactions other than public offerings of greater than 20% of the outstanding common stock or voting power of the issuer prior to the offering. Nasdaq Listing Rule 5635(d) requires stockholder approval of transactions other than public offerings of greater than 20% of the outstanding common stock or voting power of the issuer prior to the offering for less than the applicable Minimum Price. Under Rule 5635(d), the “Minimum Price” means a price that is the lower of: (i) the closing price immediately preceding the signing of the binding agreement; or (ii) the average closing price of the common stock for the five trading days immediately preceding the signing of the binding agreement. In order for the purchase price in the private placement to comply with the Minimum Price requirement under Nasdaq Listing Rule 5635(d), the Company may not issue shares in excess of 20% of the outstanding Common Stock prior to the date of the Keystone Purchase Agreement until stockholder approval allowing the issuance of the underlying shares of Common Stock is obtained.

OUR BOARD UNANIMOUSLY RECOMMENDS THAT OUR STOCKHOLDERS VOTE “FOR” THE ADJOURNMENT PROPOSAL.

Committed Equity Financings

Pursuant to the Keystone Purchase Agreement, Keystone shall: (a) purchase from the Company up to the greater of (i) 2,977,070 shares of the Common Stock and (ii) 19.99% of the total number of shares of Common Stock outstanding immediately prior to the execution of the Keystone Purchase Agreement (the “Keystone Purchase Shares”); provided however that such limitations will not apply if we obtain stockholder approval to issue additional shares of Common Stock, and (b) receive (i) 119,050 shares of Common Stock (which were issued upon the execution of the Keystone Purchase Agreement) and (ii) an additional $250,000 of shares of Common Stock at each of the 90- and 180-day anniversaries of the effectiveness of the registration statement registering the shares sold to Keystone for resale, with the number of such shares determined based upon the average of the daily volume-weighted average price (“VWAP”) for each of the five trading days immediately prior to such 90- or 180-day anniversary, in each case as consideration for Keystone’s execution and delivery of the Keystone Purchase Agreement (the “Keystone Commitment Shares”).

Pursuant to the Arena Purchase Agreement, Arena shall: (a) purchase from the Company up to $25.0 million of shares of the Common Stock, upon the terms and subject to the conditions and limitations set forth in the Arena Purchase Agreement (the “Arena Purchase Shares” and, together with the Keystone Purchase Shares, the “Purchase Shares”) and (b) receive a number of shares of Common Stock equal to 500,000 divided by the simple average of the daily VWAP of the Common Stock during the five trading days immediately preceding the effectiveness of the registration statement registering the shares sold to Arena for resale, as consideration for Arena’s execution and delivery of the Arena Purchase Agreement (the “Arena Commitment Shares” and, together with the Keystone Commitment Shares, the “Commitment Shares”).

Sales of the Company’s Common Stock to Keystone and Arena under the respective Purchase Agreements, and the timing of any sales, will be determined by the Company from time to time in the Company’s sole discretion and will depend on a variety of factors, including, among other things, market conditions, the trading price of the Common Stock and determinations by the Company regarding the use of proceeds from any sale of such Common Stock.

WHERE YOU CAN FIND MORE INFORMATIONSeries A Convertible Preferred Stock

The Company files annual, quarterlydesignated 12,580 shares of the Company’s authorized and current reports, proxy statementsunissued Preferred Stock as Series A Convertible Preferred Stock (the “Series A Preferred Stock”) and other information withestablished the SEC. The SEC maintains an Internet web site that contains reports, proxyrights, preferences and information statements, and other information regarding issuers, including us, that file electronically withprivileges of the SEC. The public can obtain any documents that we file electronically with the SEC at www.sec.gov.

This proxy statement describes the material elements of relevant contracts, exhibits and other information attached as annexes to this proxy statement. Information and statements contained in this proxy statement are qualified in all respects by referenceSeries A Preferred Stock pursuant to the copySeries A Certificate of the relevant contract or other document included as an annex to this document.

You may obtain additional copies of this proxy statement, at no cost, and you may ask any questions you may have about the Charter Amendment, the Trust Amendment or the Adjournment by contacting us at the following address or telephone number:

Phoenix Biotech Acquisition Corp.

2201 Broadway, Suite 705

Oakland, CA 94612

(215) 731-9450

You may also obtain these documents at no cost by requesting them in writing or by telephone from the Company’s proxy solicitation agent at the following address and telephone number:

Okapi Partners LLC

1212 Avenue of the Americas, 17^th Floor

New York, NY 10036

Telephone: (877) 259-6290

(banks and brokers can call at (212) 297-0720)

Email: info@okapipartners.com

In order to receive timely delivery of the documents in advance of the Special Meeting, you must make your request for information no later than December 9, 2022.

Annex A

PROPOSED AMENDMENT TO THE AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION OF PHOENIX BIOTECH ACQUISITION CORP.

                    , 2022

Phoenix Biotech Acquisition Corp., a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), DOES HEREBY CERTIFY AS FOLLOWS:

1.        The name of the Corporation is “Phoenix Biotech Acquisition Corp.”. The original certificate of incorporation wasDesignations filed with the Secretary of State of the State of Delaware, on June 8, 2021 (the “as summarized below.

Original Certificate”)

General. Each share of Series A Preferred Stock has a stated value of $1,000 per share and, when issued, the Series A Preferred Stock was fully paid and non-assessable.

Ranking. The AmendedSeries A Preferred Stock, with respect to the payment of dividends, distributions and Restatedpayments upon the liquidation, dissolution and winding up of the Company, ranks senior to all capital stock of the Company unless the Required Holders (as defined in the Series A Certificate of IncorporationDesignations) consent to the creation of other capital stock of the Company that is senior or equal in rank to the Series A Preferred Stock.

Dividends. The holders of Series A Preferred Stock will be entitled to dividends, on an as-if converted basis, equal to and in the same form as dividends actually paid on shares of Common Stock, when and if actually paid.

Purchase Rights. If at any time the Company grants, issues or sells any options, convertible securities, or rights to purchase stock, warrants, securities or other property pro rata to all or substantially all of the record holders of any class of Common Stock (the ““Purchase Rights”), then each holder of Series A Preferred Stock will be entitled to acquire, upon the terms applicable to such Purchase Rights, the aggregate Purchase Rights which such holder could have acquired if such holder had held the number of shares of Common Stock acquirable upon complete conversion of all the Series A Preferred Stock held by such holder immediately prior to the date as of which the record holders of shares of Common Stock are to be determined for the grant, issue or sale of such Purchase Rights at the Alternate Conversion Price (as defined in the Series A Certificate of Designations); subject to certain limitations on beneficial ownership.

Conversion Rights

Conversion at Option of Holder. Each holder of Series A Preferred Stock may convert all, or any part, of the outstanding Series A Preferred Stock, at any time at such holder’s option, into shares of the Common Stock (which converted shares of Common Stock are referred to as “Conversion Shares” herein) at the fixed “Conversion Price” of $10.00, which is subject to proportional adjustment upon the occurrence of any stock split, stock dividend, stock combination and/or similar transactions.

Voluntary Adjustment Right. Subject to the rules and regulations of the Nasdaq, the Company has the right, at any time, with the written consent of the Required Holders, to lower the fixed conversion price to any amount and for any period of time deemed appropriate by the Board.

Alternate Conversion Upon a Triggering Event. Following the occurrence and during the continuance of a Triggering Event (as defined below), each holder may alternatively elect to convert the Series A Preferred Stock at the “Alternate Conversion Price” equal to the lesser of:

The Series A Certificate of Designations contains standard and customary triggering events (each, a “Triggering Event”), including but not limited to: (i) the suspension from trading or the failure to list the Common Stock within certain time periods; (ii) failure to declare or pay any dividend when due; (iii) the failure to timely file or make effective a registration statement on Form S-1 pursuant to the Registration Rights Agreement, dated as of February 14, 2024, by and between the Company and the holders of Series A Preferred Stock party thereto (the “Registration Rights Agreement”), (iv) the Company’s failure to cure a conversion failure of failure to deliver shares of the Common Stock under the Structuring Warrants (as defined below), or notice of the Company’s intention not to comply with a request for conversion of any Series A Preferred Stock or a request for exercise of any Structuring Warrants, and (iv) bankruptcy or insolvency of the Company.

Other Adjustments. If 90 days or 180 days following the occurrence of the later of (x) the Stockholder Approval Date (as defined below) and (y) the earlier of (a) the effective date of the registration statement to be filed pursuant to the Registration Rights Agreement and (b) the date that the Series A Preferred Stock is eligible to be resold without restriction under Rule 144 of the Securities Act of 1933, as amended (the “Securities Act”), the Conversion Price then in effect is greater than the greater of $1.00 and the Market Price (as defined in the Series A Certificate of Designations) then in effect (the “Adjustment Price”), the Conversion Price shall automatically lower to the Adjustment Price.

Limitations on Conversion. In no event shall the Series A Preferred Stock be convertible into a number of shares of New Common Stock exceeding 19.99% of the total number of shares of Common Stock outstanding immediately prior to the execution of the Securities Purchase Agreement, except that such limitation shall not apply in the event that the Company obtains approval from the Company’s stockholders for the issuance of such shares in accordance with the applicable stock exchange rules (the date of such approval, the “Stockholder Approval Date”).

Bankruptcy Triggering Event Redemption Right.Upon any bankruptcy Triggering Event, the Company shall immediately redeem in cash all amounts due under the Series A Preferred Stock at 25% premium (or, if 18 months following the issuance date, 50% premium) to the greater of (x) the amount of shares of Series A Preferred Stock then outstanding and (y) the equity value of the shares of Series A Preferred Stock then outstanding, unless the holder waives such right to receive such payment. The equity value of the Common Stock underlying the Series A Preferred Stock is calculated using the greatest closing sale price of the Common Stock on any trading day immediately preceding such bankruptcy Triggering Event and the date the Company makes the entire payment required.

Change of Control Exchange. Upon a change of control of the Company, each holder may require the Company to exchange the holder’s shares of Series A Preferred Stock for consideration equal to the change of Control Election Price (as defined in the Series A Certificate of Designations), to be satisfied at the Company’s election in either (x) cash or (y) rights convertible into such securities or other assets to which such holder would have been entitled with respect to such shares of Common Stock had such shares of Common Stock been held by such holder upon consummation of such corporate event.

Company Optional Redemption. At any time the Company shall have the right to redeem in cash all, but not less than all, the shares of Series A Preferred Stock then outstanding at a 20% redemption premium to the greater of (x) the amount of shares being redeemed, and (y) the equity value of the Common Stock underlying the Series A Preferred Stock. The equity value of the Common Stock underlying the Series A Preferred Stock is calculated using the greatest closing sale price of the Common Stock on any trading day immediately preceding the date the Company notifies the holders of the Company’s election to redeem and the date the Company makes the entire payment required.