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As filed with the Securities and Exchange Commission on April 16, 2021May 11, 2023
Registration No. 333-254174333-      ​
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
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FORM S-3
Amendment No. 1
to
Form S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
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ASTRIA THERAPEUTICS, INC.
CATABASIS PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)
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Delaware
(State or other jurisdiction of
incorporation or organization)​
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26-3687168
(I.R.S. Employer
Identification No.)Number)
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100 High75 State Street 28
th FloorSuite 1400
Boston, MA 02110Massachusetts 02109
(617) 394-1971349-1971
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)​
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Jill C. Milne
President and Chief Executive Officer
Catabasis Pharmaceuticals,Astria Therapeutics, Inc.
100 High75 State Street 28
th FloorSuite 1400
Boston, MA 02110Massachusetts 02109
(617) 394-1971349-1971
(Name, address, including zip code, and telephone number, including area code, of agent for service)​
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Copy to:
Rosemary G. Reilly, Esq.
Wilmer Cutler Pickering Hale and Dorr LLP
60 State Street
Boston, Massachusetts 02109
Telephone: (617) 526-6000
Fax: (617) 526-5000526 5000
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Approximate date of commencement of proposed sale to the publicpublic:
: From time to time after the effective date of this Registration Statement.registration statement becomes effective.
If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐
If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ☒
If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☐
If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
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Large accelerated filer
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Accelerated filer
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Non-accelerated filer
☒
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Smaller reporting company
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Emerging growth company
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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐
CALCULATION OF REGISTRATION FEE
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Title of Each Class of
Securities to be Registered
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Amount to be
Registered(1)
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Offering Price
Per Share(2)
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Proposed Maximum
Aggregate Offering Price(2)
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Amount of
Registration Fee
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Common Stock, $0.001 par value​​​​​92,399,805​​​​​$2.69​​​​​$248,555,475.45​​​​​$27,117.41​​
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(1)
Pursuant to Rule 416 under the Securities Act of 1933, as amended (the “Securities Act”), this Registration Statement also covers such additional securities as may become issuable to prevent dilution resulting from stock splits, stock dividends and similar events.
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(2)
Pursuant to Rule 457(c), calculated on the basis of the average of the high and low prices of the Registrant’s Common Stock reported on The Nasdaq Global Market on March 5, 2021. The registrant paid a registration fee of $27,117.41 in respect of the Common Stock with a proposed maximum aggregate offering price of $248,555,475.45 in connection with the initial filing of this Registration Statement.
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The registrantRegistrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the registrantRegistrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Commission acting pursuant to said Section 8(a), may determine.
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The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it iswe are not soliciting an offeroffers to buy these securities in any statejurisdiction where the offer or sale is not permitted.
Subject to Completion,completion, dated April 16, 2021May 11, 2023
PROSPECTUS
CATABASIS PHARMACEUTICALS, INC.$250,000,000​
92,399,805 Shares of ASTRIA THERAPEUTICS, INC.​
Common Stock
Offered by the Selling StockholdersPreferred Stock
Depositary Shares
Units
Warrants​
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We may offer and sell securities from time to time in one or more offerings of up to $250,000,000 in aggregate offering price. This prospectus relatesdescribes the general terms of these securities and the general manner in which these securities will be offered. We will provide the specific terms of these securities in supplements to this prospectus. The prospectus supplements will also describe the proposed resalespecific manner in which these securities will be offered and may also supplement, update or other disposition of an aggregate of 92,399,805 shares (the “Shares”) of our common stock, par value $0.001 per share (the “Common Stock”), by the selling stockholders identifiedamend information contained in this prospectus (collectively with any of the holders’ transferees, pledgees, donees or other successors-in-interest, the “Selling Stockholders”). The Shares covered bydocument. You should read this prospectus consist of (i) 3,332,669 shares of Common Stock issued in connection with our acquisition of Quellis Biosciences, Inc.; (ii) 50,504,000 shares of Common Stock issuable upon the conversion of our Series X Convertible Preferred Stock, par value $0.001 per share (the “Series X Preferred Stock”), issued in connection with the acquisition; (iii) 2,805,000 shares of Common Stock issuable upon the conversion of the Series X Preferred Stock underlying warrants assumed by us in connection with the acquisition; (iv) 185,136 shares of Common Stock underlying warrants assumed by us in connection with the acquisition; and (v) 35,573,000 shares of Common Stock issuable upon the conversion of Series X Preferred Stock issued in a private placement transaction.any applicable prospectus supplement before you invest.
We will not receive any proceeds from the sale by the Selling Stockholders of the Shares. We are paying the cost of registering the Shares covered by this prospectus as well as various related expenses. The Selling Stockholders are responsible for all selling commissions, transfer taxes and other costs related to themay offer and sale of their shares.
Sales of the Shares by the Selling Stockholders may occur at fixed prices, at prevailing market prices at the time of sale,these securities in amounts, at prices related to the prevailing market price, at varying pricesand on terms determined at the time of sale, or at negotiated prices.offering. The Selling Stockholderssecurities may sell sharesbe sold directly to you, through agents, or through underwriters broker-dealersand dealers. If agents, underwriters or agents, who may receivedealers are used to sell the securities, we will name them and describe their compensation in the form of discounts, concessions or commissions from the Selling Stockholders, the purchasers of the shares, or both. If required, the number of shares to be sold, the public offering price of those shares, the names of any underwriters, broker-dealers or agents and any applicable commission or discount will be included in a supplement to this prospectus, called a prospectus supplement. See the disclosure under the heading “Plan of Distribution” elsewhere in this prospectus for more information about how the Selling Stockholders may sell or otherwise dispose of their Shares hereunder.
The Common StockOur common stock is tradedlisted on The Nasdaq Global Market under the symbol “CATB”“ATXS”. On April 15, 2021, the closing sale price of the Common Stock was $2.37 per share. You are urged to obtain current market quotations for the Common Stock.
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Investing in our common stockthese securities involves a high degree of risk. Please read the information contained in and incorporated by reference under the headingcertain risks. See “Risk Factors” beginning on page 64 of this prospectus, and underany similar headingssection included in any accompanying prospectus supplement and in the other documents that are filed after the date hereof and incorporated by reference intoin this prospectus.prospectus for a discussion of the factors you should carefully consider before deciding to purchase these securities.
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Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined ifpassed upon the adequacy or accuracy of this prospectus is truthful or complete.prospectus. Any representation to the contrary is a criminal offense.
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ThisThe date of this prospectus is           dated           , 20212023
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TABLE OF CONTENTS
​​​Page No.​
ABOUT THIS PROSPECTUS
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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTSWHERE YOU CAN FIND MORE INFORMATION
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PROSPECTUS SUMMARYINCORPORATION BY REFERENCE
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FORWARD-LOOKING STATEMENTS
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THE OFFERINGRISK FACTORS
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ASTRIA THERAPEUTICS, INC.
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RISK FACTORSUSE OF PROCEEDS
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USEDESCRIPTION OF PROCEEDSCAPITAL STOCK
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SELLING STOCKHOLDERSDESCRIPTION OF DEPOSITARY SHARES
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DESCRIPTION OF UNITS
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DESCRIPTION OF WARRANTS
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FORMS OF SECURITIES
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PLAN OF DISTRIBUTION
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LEGAL MATTERS
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EXPERTS
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WHERE YOU CAN FIND MORE INFORMATIONSIGNATURES
​​​​17II-6 ​​
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INCORPORATIONSIGNATURES AND POWER OF CERTAIN INFORMATION BY REFERENCEATTORNEY
​​​​17II-6​​
 
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ABOUT THIS PROSPECTUS
Unless the context otherwise indicates, references in this prospectus to “we,” “our” and “us” refer, collectively, to Astria Therapeutics, Inc., a Delaware corporation, and its consolidated subsidiaries. This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, which we refer to as the “SEC,” utilizing a “shelf” registration process. Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus in one or more offerings for an aggregate initial offering price of up to $250,000,000.
This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus any applicableand the accompanying prospectus supplement andtogether with the additional information incorporated by reference in this prospectus before making an investment indescribed under the securities of the Company. Seeheading “Where You Can Find More Information” and “Incorporationbeginning on page 2 of Certain Information by Reference” for additional information. this prospectus.
You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or ain any related free writing prospectus supplement.filed by us with the SEC. We have not authorized anyone to provide you with different information. This document may be used onlyprospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in jurisdictions where offers and salesthis prospectus or such accompanying prospectus supplement or an offer to sell or the solicitation of thesean offer to buy such securities are permitted.in any circumstances in which such offer or solicitation is unlawful. You should assume that the information containedappearing in this prospectus, or in any documentprospectus supplement, the documents incorporated by reference and any related free writing prospectus is accurate only as of any date on the front cover of the applicable document.their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since that date.those dates.
Unless otherwise indicated, references

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WHERE YOU CAN FIND MORE INFORMATION
We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the terms “Catabasis,” “our,” “us,” “we”public over the Internet at the SEC’s website at http://www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at www.astriatx.com. Our website is not a part of this prospectus and is not incorporated by reference in this prospectus.
This prospectus is part of a registration statement we filed with the SEC. This prospectus omits some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information about us and our consolidated subsidiaries and the securities we are offering. Statements in this prospectus concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings and the exhibits attached thereto. You should review the complete document to evaluate these statements.
INCORPORATION BY REFERENCE
The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below (File No. 001-37467) and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the “Company” referExchange Act (in each case, other than those documents or the portions of those documents not deemed to Catabasis Pharmaceuticals,be filed) between the date of the initial registration statement and the effectiveness of the registration statement and following the effectiveness of the registration statement until the offering of the securities under the registration statement is terminated or completed:
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Annual Report on Form 10-K for the fiscal year ended December 31, 2022, including the information specifically incorporated by reference into the Annual Report on Form 10-K from our Definitive Proxy Statement on Schedule 14A filed with the SEC on April 20, 2023;
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Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2023;
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Current Reports on Form 8-K filed January 5, 2023 (only Item 8.01), February 2, 2023 and March 31, 2023; and
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The description of our common stock contained in our Registration Statement on Form 8-A filed on June 23, 2015, including any amendments or reports filed for the purpose of updating such description.
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You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:
Astria Therapeutics, Inc. and its wholly-owned subsidiaries, on a consolidated basis.
75 State Street, Suite 1400
Boston, MA 02109
Attn: Investor Relations
(617) 349-1971
 
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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA
This prospectus includes and incorporates forward-looking statementsthe information incorporated by reference in this prospectus include “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, (the “Securities Act”),or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).Act. All statements, other than statements of historical facts, includedcontained or incorporated by reference in this prospectus, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans and objectives of management and expected market growth are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.
These forward-looking statements include, among other things, statements about:
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our expectations regarding the potential significance of the preliminary results from the Phase 1a STAR-0215 clinical trial and the anticipated nature and timing of receipt of the data from additional cohorts in such trial;
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our planned filing of an initial investigational new drug application, or IND, for QLS-215, andexpectations regarding the timing, nature, goals and results of our planned Phase 1a and Phase 1b/2 clinical trialstrial of QLS-215, includingSTAR-0215 and that favorable results from such trialstrial could establish proofallow us to move directly into a pivotal trial of concept for the differentiation of QLS-215STAR-0215 as a potential treatment for hereditary angioedema, or HAE;
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our expectations about the design of a pivotal clinical trial for STAR-0215 as a potential treatment for HAE, assuming positive data from the Phase 1b/2 trial;
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our expectations about the unmet medical need for HAE, the potential differentiating attributes of QLS-215STAR-0215 as a potential treatment for HAE, along with the potential market impact of such differentiation, the potential of QLS-215STAR-0215 to be a best-in-class monoclonal antibody inhibitor of plasma kallikrein able to provide long-acting, effective attack prevention for HAE, and our vision for STAR-0215 to become the first-choice preventative treatment for HAE and with administration every three or six months with the goal of normalizing the lives of people living with HAE;
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the nature and anticipated growth of the global HAE market and HAE therapies;
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our expectations thatplans to improve the acquisitionformulation of Quellis may be an opportunitySTAR-0215 and corresponding work to create significant stockholder value;develop a drug-device combination for STAR-0215 for potential use in late-stage clinical trials and commercially, if approved;
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our expectations that we have identified ascaled the manufacturing process for STAR-0215 cell line for QLS-215 and the ability of such cell linein a manner to generate sufficient material for our planned QLS-215 toxicology studiesSTAR-0215 nonclinical and the master cell bank, and our plans and timetable for initiating current Good Manufacturing Practices, or cGMP, manufacturing of QLS-215;clinical studies;
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our expectations regarding our ability to expand our pipeline;
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the potential benefits of any future acquisition, in-license, collaboration or pre-clinicalpreclinical development activities;
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our manufacturing plans, capabilities and strategy;
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our intellectual property position and strategy;
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our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;
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financing, including additional financing to fund our use of the proceeds from the private placement completed in February 2021;long-term operations;
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developments relating to our competitors and our industry; and
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the impact of government laws and regulations.
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We may not actually achieve the plans, intentions or expectations disclosed in ourYou are cautioned that these forward-looking statements are only predictions and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentionsare subject to risks, uncertainties and expectations disclosedassumptions that are referenced in the forward-lookingsection of any accompanying prospectus supplement entitled “Risk Factors.” You should also carefully review the risk factors and cautionary statements we make. We have included important factorsdescribed in the cautionary statements included in this prospectus, particularly in the “Risk Factors” section, that could cause actual results or eventsother documents we file from time to differ materially from the forward-looking statements that we make. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, collaborations, joint ventures or investments that we may make or enter into.
You should read this prospectustime with the understanding thatSEC, specifically our actual future results may be materially different from what we expect.most recent Annual Report on Form 10-K, our Quarterly Reports on Form 10-Q and our Current Reports on Form 8-K. We do not assume anyundertake no obligation to revise or update any forward-looking statement, whether as a result of new information, future events or otherwise,statements, except asto the extent required by law.
 
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PROSPECTUS SUMMARY
This summary highlights important features of this offering and the information included or incorporated by reference in this prospectus. This summary does not contain all of the information that you should consider before investing in our common stock. You should read the entire prospectus carefully, especially the risks of investing in our common stock discussed under “Risk Factors.”
Overview
We are a biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics. Our mission is to bring hope with life-changing therapies to patients and families that are affected by rare diseases. Our lead product candidate is QLS-215, a potential best-in-class monoclonal antibody inhibitor of plasma kallikrein in preclinical development for the treatment of hereditary angioedema, or HAE, a rare, debilitating and potentially life-threatening disease.
In January 2021, as further described below, we acquired Quellis Biosciences, Inc., or Quellis, including the QLS-215 program, and announced a private placement that, upon closing in February 2021, resulted in gross proceeds to us of approximately $110.0 million before deducting placement agent and other offering expenses. In November 2020, after we stopped the development of our edasalonexent program as a potential treatment for Duchenne Muscular Dystrophy, or DMD, we decided to explore and evaluate strategic options and engaged Ladenburg Thalmann & Co., Inc. as our strategic financial advisor. The acquisition of Quellis was the result of our evaluation of strategic options and we believe that the acquisition represents an opportunity to create substantial value for our stockholders.
HAE is a rare, debilitating and potentially life-threatening disease. The treatment options for patients with HAE have improved, however there is remaining unmet medical need and the global market for HAE therapy is strong and growing. The vision for our lead program, QLS-215, is to develop a best-in-class monoclonal antibody inhibitor of plasma kallikrein for HAE prophylaxis that is able to treat HAE by achieving sustained blood levels of QLS-215 with infrequent dosing. Plasma kallikrein is a critical component of HAE that causes pathologic vascular permeability, vasodilation and ultimately excessive tissue swelling. QLS-215 is a humanized monoclonal antibody targeting plasma kallikrein that has shown in preclinical studies that it may potentially enable patients to dose less frequently and potentially be more effective than existing HAE treatments. QLS-215 is currently in preclinical development and we expect to submit an Investigational New Drug application, or IND, for QLS-215 in the first half of 2022 and plan to initiate a Phase 1a clinical trial with initial results anticipated by the end of 2022. Subsequently, assuming positive data from the Phase 1a clinical trial, we plan to initiate a Phase 1b/2 trial in patients with HAE in 2023 with initial results anticipated by the end of 2023. We believe that these clinical trials have the opportunity to establish proof of concept for the differentiated profile of QLS-215.
Previously, our lead program was edasalonexent, which was in Phase 3 clinical development for the treatment of DMD. In October 2020, we announced that the Phase 3 PolarisDMD trial of edasalonexent did not meet its primary endpoint, which was a change from baseline in the North Star Ambulatory Assessment over one year of treatment with edasalonexent compared to placebo. In addition, we announced that the secondary endpoint timed function tests (time to stand, 10-meter walk/run and 4-stair climb) did not show statistically significant improvements. Based on these results, we stopped activities related to the development of edasalonexent, including the GalaxyDMD open-label extension trial. The Phase 3 Polaris DMD trial was a one-year placebo-controlled trial designed to evaluate the safety and efficacy of edasalonexent in boys ages 4-7 (up to 8th birthday) with DMD. The trial enrolled 131 boys across eight countries, with any mutation type, who were not on steroids. Edasalonexent was well-tolerated, consistent with the safety profile seen to date. The majority of adverse events were mild in nature and the most common treatment-related adverse events were diarrhea, vomiting, abdominal pain and rash. There were no treatment-related serious adverse events and no dose reductions. Data from the Phase 3 PolarisDMD trial will be further analyzed and we expect to publish these data.
January 2021 Quellis Acquisition and February 2021 Financing
In January 2021, we acquired Quellis pursuant to an Agreement and Plan of Merger, or the Merger Agreement, by and among us, Cabo Merger Sub I, Inc., a Delaware corporation and our wholly owned

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subsidiary, or the First Merger Sub, Cabo Merger Sub II, LLC, a Delaware limited liability company and our wholly owned subsidiary, or the Second Merger Sub, and Quellis. Pursuant to the Merger Agreement, the First Merger Sub merged with and into Quellis, pursuant to which Quellis was the surviving entity and became a wholly owned subsidiary of Catabasis, or the First Merger. Immediately following the First Merger, Quellis merged with and into the Second Merger Sub, pursuant to which the Second Merger Sub was the surviving entity, or the Second Merger and, together with the First Merger, the Merger. Under the terms of the Merger Agreement, at the closing of the Merger, we issued to the Quellis stockholders 3,332,669 shares of our common stock, and 50,504 shares of newly designated Series X Preferred Stock (as described below). In addition, we assumed outstanding Quellis stock options, which became options for our common stock, and assumed a warrant exercisable for Quellis common stock, which became a warrant to purchase 2,805 shares of Series X Preferred Stock at an exercise price of $341.70 per share, and a warrant to purchase 185,136 shares of our common stock at an exercise price of $0.35 per share.
In January 2021, we also entered into a Stock Purchase Agreement, or the Purchase Agreement, with certain institutional and accredited investors, or the Investors, pursuant to which, we sold an aggregate of 35,573 shares of Series X Preferred Stock for an aggregate purchase price of $110.0 million, or the February 2021 Financing. Subject to stockholder approval, each share of Series X Preferred Stock issued in the Merger and pursuant to the Purchase Agreement is convertible into 1,000 shares of common stock. Pursuant to the Merger Agreement, we have agreed to hold a stockholders’ meeting to submit the following matters to our stockholders for their consideration: (i) the approval of the conversion of the Series X Preferred Stock into shares of common stock in accordance with Nasdaq Listing Rule 5635(a), or the Conversion Proposal and (ii) if necessary or appropriate, the approval of an amendment to our certificate of incorporation to authorize sufficient shares of common stock after the conversion of the Series X Preferred Stock issued pursuant to the Merger Agreement and the Purchase Agreement and/or to effectuate a reverse stock split, or the Charter Amendment Proposal, and together with the Conversion Proposal, the Meeting Proposals. Assuming stockholder approval of the Conversion Proposal, on the fourth business day after such approval, each share of Series X Preferred Stock then outstanding would automatically convert into 1,000 shares of common stock, subject to certain beneficial ownership limitations, including that a holder of Series X Preferred Stock is prohibited from converting shares of Series X Preferred Stock into shares of common stock if, as a result of such conversion, such holder, together with its affiliates, would beneficially own more than a specified percentage (to be initially set at 9.99% and thereafter adjustable by the holder to a number between 4.99% and 19.99%) of the total number of shares of common stock issued and outstanding immediately after giving effect to such conversion. Shares of Series X Preferred Stock not converted automatically are thereafter subject to conversion at the option of the holder.
Corporate Information
We were incorporated under the laws of the State of Delaware on June 26, 2008 under the name Catabasis Pharmaceuticals, Inc. Our executive offices are located at 100 High Street, 28th Floor, Boston, Massachusetts, 02110, and our telephone number is (617) 349-1971. Our website address is www.catabasis.com. The information contained on, or that can be accessed through, our website is not a part of this prospectus. We have included our website address in this prospectus solely as an inactive textual reference.

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THE OFFERING
Common Stock offered by selling stockholder
92,399,805 shares.
Use of proceeds
We will not receive any proceeds from the sale of shares in this offering.
Nasdaq Global Market symbol
CATB.

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RISK FACTORS
Investing in our common stocksecurities involves significant risk. Prior to making a high degreedecision about investing in our securities, you should carefully consider the specific factors discussed under the heading “Risk Factors” in the applicable prospectus supplement and in any free-writing prospectus that we authorize for use in connection with an offering, together with all of risk. The trading price of our common stock could decline and you might lose allthe other information contained or part of your investment. You should consider carefullyincorporated by reference in the prospectus supplement or appearing or incorporated by reference in this prospectus, including the risks, uncertainties and uncertainties describedassumptions discussed under the sections captionedheading “Risk Factors” and “Summary of the Material Risks Associated with Our Busines” containedincluded in our most recent Annual Report on Form 10-K, and other filingsas revised or supplemented by our most recent Quarterly Report on Form 10-Q or our current reports on Form 8-K that we makehave filed with the SEC, which are incorporated herein by reference, and which may be amended, supplemented or superseded from time to time whichby other reports we file with the SEC in the future. The risks and uncertainties we have described are incorporated by reference hereinnot the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations. The occurrence of any of these risks might cause you to lose all or part of your investment in their entirety, together with otherthe offered securities.

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ASTRIA THERAPEUTICS, INC.
This summary highlights selected information contained elsewhere in this prospectus and in the documents we incorporate by reference. This summary does not contain all of the information you should consider before making an investment decision. You should read this entire prospectus carefully, especially the risks discussed under “Risk Factors” beginning on page 4 of this prospectus, along with our consolidated financial statements and documentsnotes to those consolidated financial statements and the other information incorporated by reference in this prospectus.
We are a biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics. Our mission is to bring hope with life-changing therapies to patients and families that are affected by rare and niche allergic and immunological diseases. Our lead product candidate is STAR-0215, a potential best-in-class monoclonal antibody inhibitor of plasma kallikrein in clinical development for the treatment of hereditary angioedema, or HAE, a rare, debilitating and potentially life-threatening disease. STAR-0215 has the potential to be the most patient-friendly chronic treatment option for HAE, based on the data generated to date and the existing HAE treatment landscape.
The treatment options for patients with HAE have improved in recent years, however, there is remaining unmet medical need and the global market for HAE therapy is strong and growing. The goal for STAR-0215 is to develop a best-in-class monoclonal antibody inhibitor of plasma kallikrein able to provide long-acting, effective attack prevention for HAE. Our vision for STAR-0215 is to become the first-choice preventative treatment for HAE with administration every three or six months with the goal of normalizing the lives of people living with HAE. Targeted plasma kallikrein inhibition can prevent HAE attacks by suppressing the pathway that generates bradykinin and causes excessive swelling. STAR-0215 is currently in clinical development.
Our principal executive offices are located at 75 State Street, Suite 1400, Boston, Massachusetts 02109, and our telephone number is (617) 349-1971.

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USE OF PROCEEDS
We intend to use the net proceeds from the sale of any securities offered under this prospectus andfor general corporate purposes unless otherwise indicated in anythe applicable prospectus supplement. The risksGeneral corporate purposes may include research and uncertainties described indevelopment expenditures, repayment and refinancing of debt, working capital and capital expenditures. We have not determined the Risk Factors and Summaryamount of net proceeds to be used specifically for such purposes. As a result, management will retain broad discretion over the allocation of the Material Risks Associated with Our Busines sectionsnet proceeds of our most recent Annual Report on Form 10-K are not the only ones facing our company. Additional risks and uncertainties may also impair our business operations. If any of such risks actually occur, our business, financial condition, results of operations or cash flows would likely suffer materially. In that case, the trading price of our common stock could fall, and you may lose all or part of the money you paid to buy our common stock.offering.
 
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USEDESCRIPTION OF PROCEEDSCAPITAL STOCK
WeThe following description of our capital stock is intended as a summary only and therefore is not a complete description of our capital stock. This description is based upon, and is qualified by reference to, our certificate of incorporation, our by-laws and applicable provisions of Delaware corporate law. You should read our certificate of incorporation and by-laws, which are filed as exhibits to the registration statement of which this prospectus forms a part, for the provisions that are important to you.
Our authorized capital stock consists of 150,000,000 shares of common stock, $0.001 par value per share, and 5,000,000 shares of preferred stock, $0.001 par value per share. As of March 31, 2023, 27,986,718 shares of common stock were outstanding and 31,107 shares of our Series X Preferred Stock were outstanding.
Common Stock
Voting Rights.   Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders, except that unless otherwise required by law, holders of our common stock are not entitled to vote on any amendment to the certificate of incorporation that relates solely to the terms of one or more outstanding series of preferred stock, if the holders of such affected series are entitled, either separately or together as a class with the holders of one or more such other series, to vote thereon pursuant to the certificate of incorporation. Holders of our common stock do not have cumulative voting rights.
An election of directors will notbe decided by a plurality of the votes cast by the stockholders entitled to vote on the election at a duly held stockholders’ meeting at which a quorum is present. All other questions will be decided by a majority of the votes cast by stockholders entitled to vote thereon at a duly held meeting of stockholders at which a quorum is present, except when a different vote is required by law, our certificate of incorporation or by-laws.
Dividends.   Holders of common stock are entitled to receive proportionately any proceeds fromdividends as may be declared by our board of directors, subject to any preferential dividend or other rights of any series of preferred stock that we may designate and issue in the salefuture.
Liquidation and Dissolution.   In the event of our liquidation or dissolution, the holders of common stock are entitled to receive proportionately our net assets available for distribution to stockholders after the payment of all debts and other liabilities and subject to the prior rights of any outstanding preferred stock.
Other Rights.   Holders of common stock have no preemptive, subscription, redemption or conversion rights. The rights, preferences and privileges of holders of common stock are subject to and may be adversely affected by the rights of the holders of shares byof any series of preferred stock that we may designate and issue in the Selling Stockholders.future.
Transfer Agent and Registrar.   The Selling Stockholders will pay any underwriting discountstransfer agent and commissions and expenses incurred by the Selling Stockholdersregistrar for brokerage, accounting, tax or legal services or any other expenses incurred by the Selling Stockholders in disposing of the shares. We will bear all other costs, fees and expenses incurred in effecting the registration of the shares covered by this prospectus, including, without limitation, all registration and filing fees,our common stock is American Stock Transfer & Trust Company, LLC.
Listing on The Nasdaq Global Market.   Our common stock is listed on The Nasdaq Global Market listing fees and fees and expensesunder the symbol “ATXS.”
Preferred Stock
General Description
Under our restated certificate of incorporation, we are authorized to issue “blank check” preferred stock, which may be issued in one or more series upon authorization of our counselboard of directors. Our board of directors is authorized to fix the designation of the series, the number of authorized shares of the series, dividend rights and terms, conversion rights, voting rights, redemption rights and terms, liquidation preferences and any other rights, powers, preferences and limitations applicable to each series of preferred stock. The authorized shares of our accountants.preferred stock are available for issuance without further action by our
 
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SELLING STOCKHOLDERS
This prospectus coversstockholders, unless such action is required by applicable law or the resale or other disposition from time to time byrules of any stock exchange on which our securities may be listed. If the Selling Stockholders identified in the table below of up to an aggregate of 92,399,805approval of our Shares.
On January 28, 2021, we completed our acquisition of Quellis in accordance withstockholders is not required for the Merger Agreement, pursuant to which we issued (i) 3,332,669 shares of Common Stock and (ii) 50,504 shares of Series X Preferred Stock that are convertible into an aggregate of 50,504,000 shares of Common Stock in accordance with the terms of the Certificate of Designation and we reserved for issuance (iii) 2,805,000 shares of Common Stock issuable upon the conversion of Series X Preferred Stock underlying warrants assumed by us and (iv) 185,136 shares of Common Stock underlying warrants assumed by us. Also on January 28, 2021, we entered into the Purchase Agreement, pursuant to which we sold an aggregate of 35,573 shares of Series X Preferred Stock for an aggregate purchase price of approximately $110.0 million. Subject to stockholder approval, each share of Series X Preferred Stock is convertible into 1,000 shares of Common Stock. The preferences, rights and limitations initially applicable to the Series X Preferred Stock are set forth in the Certificate of Designation of Preferences, Rights and Limitations of the Series X Preferred Stock filed with the Secretary of State of the State of Delaware on January 28, 2021 (the “Certificate of Designation”). We are registering the above-referenced Shares to permit the Selling Stockholders and their transferees, pledgees, donees or other successors-in-interest that receive their shares after the date of this prospectus to resell or otherwise dispose of the shares in the manner contemplated under “Plan of Distribution” herein.
The following table sets forth the name of the Selling Stockholders, the number of shares of our Common Stock owned bypreferred stock, our board may determine not to seek stockholder approval. The specific terms of any series of preferred stock offered pursuant to this prospectus will be described in the Selling Stockholders, the numberprospectus supplement relating to that series of sharespreferred stock.
A series of our Common Stockpreferred stock could, depending on the terms of such series, impede the completion of a merger, tender offer or other takeover attempt. Our board of directors will make any determination to issue preferred shares based upon its judgment as to the best interests of our stockholders. Our directors, in so acting, could issue preferred stock having terms that could discourage an acquisition attempt through which an acquirer may be able to change the composition of our board of directors, including a tender offer or other transaction that some, or a majority, of our stockholders might believe to be in their best interests or in which stockholders might receive a premium for their stock over the then-current market price of the stock.
The preferred stock has the terms described below unless otherwise provided in the prospectus supplement relating to a particular series of preferred stock. You should read the prospectus supplement relating to the particular series of preferred stock being offered under this prospectusfor specific terms, including:
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the designation and stated value per share of the preferred stock and the number of shares offered;
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•
the amount of liquidation preference per share;
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•
the price at which the preferred stock will be issued;
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•
the dividend rate, or method of calculation of dividends, the dates on which dividends will be payable, whether dividends will be cumulative or noncumulative and, if cumulative, the dates from which dividends will commence to accumulate;
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•
any redemption or sinking fund provisions;
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•
if other than the currency of the United States, the currency or currencies including composite currencies in which the preferred stock is denominated and/or in which payments will or may be payable;
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•
any conversion provisions;
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•
whether we have elected to offer depositary shares as described under “Description of Depositary Shares”; and
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•
any other rights, preferences, privileges, limitations and restrictions on the preferred stock.
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The preferred stock will, when issued, be fully paid and non-assessable. Unless otherwise specified in the prospectus supplement, each series of preferred stock will rank equally as to dividends and liquidation rights in all respects with each other series of preferred stock. The rights of holders of shares of each series of preferred stock will be subordinate to those of our Common Stock thatgeneral creditors.
As described under “Description of Depositary Shares,” we may, at our option, with respect to any series of preferred stock, elect to offer fractional interests in shares of preferred stock, and provide for the issuance of depositary receipts representing depositary shares, each of which will represent a fractional interest in a share of the series of preferred stock. The fractional interest will be owned after this offeringspecified in the prospectus supplement relating to a particular series of preferred stock.
Rank.   Unless otherwise specified in the prospectus supplement, the preferred stock will, with respect to dividend rights and rights upon our liquidation, dissolution or winding up of our affairs, rank:
•
senior to our common stock and to all equity securities ranking junior to such preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs;
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•
on a parity with all equity securities issued by the Selling Stockholders assuming all of the Shares registered for resale hereby are sold. The number of shares set forth below assumes the conversion of one share of Series X Preferred Stock into 1,000 shares of Common Stock. The Selling Stockholders may sell some, all or none of their Shares. We do not know how long the Selling Stockholders will hold the Shares before selling them, and we currently have no agreements, arrangements or understandings with the Selling Stockholders regarding the sale or other disposition of any of the Shares. The Shares covered hereby may be offered from time to time by the Selling Stockholders, provided that Shares issuable upon conversion of Series X Preferred Stock may only be offered after the relevant shares of Series X Preferred Stock are converted into Common Stock pursuant tous, the terms of the Certificate of Designation. Except as otherwise disclosed herein, the Selling Stockholders do not have, and within the past three years have not had, any position, office or other material relationship with us.
Beneficial ownership reflected in the table below is as of April 5, 2021 and is determined in accordancewhich specifically provide that such equity securities rank on a parity with the rules and regulations of the SEC and includes voting or investment powerpreferred stock with respect to dividend rights or rights upon our common stock. Sharesliquidation, dissolution or winding up of our Common Stock subject to options or warrants that are currently exercisable or exercisable within 60 days of April 5, 2021 are considered outstandingaffairs; and beneficially owned by the person holding the options or warrants for the purpose of calculating the percentage ownership of that person but not for the purpose of calculating the percentage ownership of any other person. The information set forth below is based upon information obtained from the Selling Stockholders and upon information in our possession regarding the issuance of the Shares in connection with the private placement and the Merger. The percentage of Common Stock owned after the offering is based on 23,417,006 shares of common stock outstanding as of April 5, 2021, and, for each Selling Stockholder, assumes the conversion of only the Series X Preferred Stock owned by such Selling Stockholder but not the Series X Preferred Stock owned by any other Selling Stockholder.
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Shares Beneficially
Owned Before
Offering(2)
​​
Shares
Offered
​​
Shares Beneficially
Owned After
Offering(3)
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Selling Stockholder(1)
​​Number​​Percent​
Lazarus Life Sciences I, LLC(4)
​​​​8,777,373​​​​​8,777,373​​​​​—​​​​​*​​
Entities affiliated with Perceptive(5)
​​​​37,704,551​​​​​37,704,551​​​​​—​​​​​*​​
Entities affiliated with Xontogeny(6)
​​​​8,777,373​​​​​8,777,373​​​​​—​​​​​*​​
Entities affiliated with Fairmount(7)
​​​​4,092,166​​​​​4,092,166​​​​​—​​​​​*​​
Xencor, Inc.(8)
​​​​4,187,206​​​​​4,187,206​​​​​—​​​​​*​​
RA Capital Healthcare Fund, L.P.(9)
​​​​5,174,000​​​​​5,174,000​​​​​—​​​​​*​​
Entities affiliated with Cormorant(10)
​​​​4,526,000​​​​​4,526,000​​​​​—​​​​​*​​
Logos Global Master Fund LP(11)
​​​​3,234,000​​​​​3,234,000​​​​​—​​​​​*​​
Entities affiliated with Venrock(12)
​​​​3,234,000​​​​​3,234,000​​​​​—​​​​​*​​
Entities affiliated with Boxer Capital(13)
​​​​1,940,000​​​​​1,940,000​​​​​​​​​​​*​​
Acorn Bioventures, L.P.(14)
​​​​1,617,000​​​​​1,617,000​​​​​—​​​​​*​​
Commodore Capital Master LP(15)
​​​​1,617,000​​​​​1,617,000​​​​​—​​​​​*​​
Citadel Multi-Strategy Equities Master Fund Ltd.(16)
​​​​1,294,000​​​​​1,294,000​​​​​—​​​​​*​​
Entities affiliated with Acuta(17)
​​​​1,896,0000​​​​​1,294,000​​​​​602,000​​​​​2.4%​​
Sphera Biotech Master Fund, LP(18)
​​​​1,294,000​​​​​1,294,000​​​​​—​​​​​*​​
Wedbush Healthcare Partners 2021 Fund, LLC(19)
​​​​404,000​​​​​404,000​​​​​—​​​​​*​​
Serrado Opportunity Fund LLC(20)
​​​​243,000​​​​​243,000​​​​​—​​​​​*​​
Viridian, LLC(21)
​​​​2,990,136​​​​​2,990,136​​​​​—​​​​​*​​
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*•
Indicates less than 1%junior to all equity securities issued by us, the terms of which specifically provide that such equity securities rank senior to the preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs.
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(1)
The term “equity securities” does not include convertible debt securities.
Dividends.   Holders of the preferred stock of each series will be entitled to receive, when, as and if declared by our board of directors, cash dividends at such rates and on such dates described in the prospectus supplement. Different series of preferred stock may be entitled to dividends at different rates or based on different methods of calculation. The dividend rate may be fixed or variable or both. Dividends will be payable to the holders of record as they appear on our stock books on record dates fixed by our board of directors, as specified in the applicable prospectus supplement.
Dividends on any series of preferred stock may be cumulative or noncumulative, as described in the applicable prospectus supplement. If required, information about other selling stockholders, exceptour board of directors does not declare a dividend payable on a dividend payment date on any series of noncumulative preferred stock, then the holders of that noncumulative preferred stock will have no right to receive a dividend for that dividend payment date, and we will have no obligation to pay the dividend accrued for that period, whether or not dividends on that series are declared payable on any future transferees, pledgees, doneesdividend payment dates. Dividends on any series of cumulative preferred stock will accrue from the date we initially issue shares of such series or such other successors-in-interestdate specified in the applicable prospectus supplement.
No dividends may be declared or paid or funds set apart for the payment of any dividends on any parity securities unless full dividends have been paid or set apart for payment on the preferred stock. If full dividends are not paid, the preferred stock will share dividends pro rata with the parity securities.
No dividends may be declared or paid or funds set apart for the payment of dividends on any junior securities unless full dividends for all dividend periods terminating on or prior to the date of the Selling Stockholders nameddeclaration or payment will have been paid or declared and a sum sufficient for the payment set apart for payment on the preferred stock.
Liquidation Preference.   Upon any voluntary or involuntary liquidation, dissolution or winding up of our affairs, then, before we make any distribution or payment to the holders of any common stock or any other class or series of our capital stock ranking junior to the preferred stock in the table above, willdistribution of assets upon any liquidation, dissolution or winding up of our affairs, the holders of each series of preferred stock shall be entitled to receive out of assets legally available for distribution to stockholders, liquidating distributions in the amount of the liquidation preference per share set forth in athe prospectus supplement, plus any accrued and unpaid dividends thereon. Such dividends will not include any accumulation in respect of unpaid noncumulative dividends for prior dividend periods. Unless otherwise specified in the prospectus supplement, after payment of the full amount of their liquidating distributions, the holders of preferred stock will have no right or amendmentclaim to any of our remaining assets. Upon any such voluntary or involuntary liquidation, dissolution or winding up, if our available assets are insufficient to pay the amount of the liquidating distributions on all outstanding preferred stock and the corresponding amounts payable on all other classes or series of our capital stock ranking on parity with the preferred stock and all other such classes or series of shares of capital stock ranking on parity with the preferred stock in the distribution of assets, then the holders of the preferred stock and all other such classes or series of capital stock ranking on parity with the preferred stock will share ratably in any such distribution of assets in proportion to the registration statementfull liquidating distributions to which they would otherwise be entitled.
Upon any such liquidation, dissolution or winding up and if we have made liquidating distributions in full to all holders of which this prospectus is a part. Additionally, post-effective amendmentspreferred stock, we will distribute our remaining assets among the holders of any other classes or series of capital stock ranking junior to the registration statementpreferred stock according to their respective rights and preferences and, in each case, according to their respective number of shares. For such purposes, our consolidation or merger with or into any other corporation, trust or entity, or the sale, lease or conveyance of all or substantially all of our property or assets will not be deemed to constitute a liquidation, dissolution or winding up of our affairs.
Redemption.   If so provided in the applicable prospectus supplement, the preferred stock will be filedsubject to disclose any material changes tomandatory redemption or redemption at our option, as a whole or in part, in each case upon the plan of distribution fromterms, at the description containedtimes and at the redemption prices set forth in the final prospectus.
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(2)such prospectus supplement.
Includes shares of Common Stock issuable upon conversion of Series X Preferred Stock.
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(3)
Assumes all shares offered by the Selling Stockholders hereby are sold and that the Selling Stockholders buy or sell no additional shares of Common Stock prior to the completion of this offering. The beneficial ownership numbers and percentages shown assume the conversion of Series X Preferred Stock into Common Stock without regard for any applicable limitations on beneficial ownership.
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(4)
Based on information provided to the Company by the Selling Stockholder. Consists of 543,373 shares of Common Stock issued in the Merger and (ii) 8,234,000 shares of Common Stock underlying 8,234 shares of Series X Preferred Stock issued in the Merger. The address of the Selling Stockholder is 2001 Market Street Suite 2500 Philadelphia, PA 19103.
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(5)
Based on information provided to the Company by the Selling Stockholders. Consists of (i) 1,933,551 shares of Common Stock issued to Perceptive Xontogeny Venture Fund, LP in the Merger, (ii) 29,303,000 shares of Common Stock underlying 29,303 shares of Series X Preferred Stock issued to Perceptive Xontogeny Venture Fund, LP in the Merger, (iii) 1,617,000 shares of Common Stock underlying 1,617 shares of Series X Preferred Stock issued to Perceptive Xontogeny Venture Fund, LP in the private placement and (iv) 4,851,000 shares of Common Stock underlying 4,851 shares of Series X Preferred Stock issued to Perceptive Life Sciences Master Fund, LTD. in the private placement. Joseph E. Edelman is the natural person who exercises voting and dispositive power over the shares. The address for Xontogeny, LLC is 240 Newbury Street, Boston, MA 02116. The address for Perceptive Xontogeny Venture Fund, LP and Perceptive Life Sciences Master Fund, LTD. is 51 Astor Pl, Floor 10, New York, NY 10003.
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The prospectus supplement relating to a series of preferred stock that is subject to mandatory redemption will specify the number of shares of preferred stock that shall be redeemed by us in each year commencing after a date to be specified, at a redemption price per share to be specified, together with an amount equal to all accrued and unpaid dividends thereon to the date of redemption. Unless the shares have a cumulative dividend, such accrued dividends will not include any accumulation in respect of unpaid dividends for prior dividend periods. We may pay the redemption price in cash or other property, as specified in the applicable prospectus supplement. If the redemption price for preferred stock of any series is payable only from the net proceeds of the issuance of shares of our capital stock, the terms of such preferred stock may provide that, if no such shares of our capital stock shall have been issued or to the extent the net proceeds from any issuance are insufficient to pay in full the aggregate redemption price then due, such preferred stock shall automatically and mandatorily be converted into the applicable shares of our capital stock pursuant to conversion provisions specified in the applicable prospectus supplement. Notwithstanding the foregoing, we will not redeem any preferred stock of a series unless:
(6)•
Basedif that series of preferred stock has a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full cumulative dividends on information provided to the Company bypreferred stock for all past dividend periods and the Selling Stockholder. Consists of (i) 543,373 shares of Common Stock issued to Xontogeny, LLC in the Merger and (ii) 8,234,000 shares of Common Stock underlying 8,234 shares of Series X Preferred Stock issued to Xontogeny, LLC in the Merger. Christopher Garabedian, Joseph Edelman and Adam Stone have shared voting and dispositive power with respect to the shares held by Xontogeny LLC. The principal address of Xontogeny LLC is 240 Newbury Street, Suite 201, Boston, MA 02116.then current dividend period; or
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(7)•
Basedif such series of preferred stock does not have a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full dividends for the then current dividend period.
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In addition, we will not acquire any preferred stock of a series unless:
•
if that series of preferred stock has a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full cumulative dividends on information provided to the Company by the Selling Stockholder. Consists of (i) 53,166all outstanding shares of Common Stock issued to Fairmount SPV II, LLC insuch series of preferred stock for all past dividend periods and the Merger, (ii) 805,000 shares of Common Stock underlying 805 shares of Series X Preferred Stock issued to Fairmount SPV II, LLC in Merger, (iii) 271,000 shares of Common Stock underlying 271 shares of Series X Preferred Stock issued to Fairmount Healthcare Fund LP in the private placement and (iv) 2,963,000 shares of Common Stock underlying 2,963 shares of Series X Preferred Stock issued to Fairmount Healthcare Fund II LP in the private placement. Fairmount Funds Management LLC is the Class A Member of Fairmount SPV II, LLC, Fairmount Healthcare Fund GP LLC is the general partner of Fairmount Healthcare Fund LP and Fairmount Healthcare Fund II GP LLC is the general partner of Fairmount Healthcare Fund II LP. Fairmount Funds Management LLC is the investment manager of Fairmount SPV II, LLC, LLC, Fairmount Healthcare Fund LP and Fairmount Healthcare Fund II LP. Fairmount Funds Management LLC, as the investment manager, along with Fairmount Healthcare Fund GP LLC and Fairmount Healthcare Fund II GP LLC, as the general partners, exercise voting and investment power over Fairmount SPV II, LLC, Fairmount Healthcare Fund LP and Fairmount Healthcare Fund II LP, respectively. Fairmount Funds Management LLC disclaims beneficial ownership of securities held by Fairmount SPV II, LLC except to the extent of their pecuniary interest therein Fairmount Healthcare Fund GP LLC and Fairmount Funds Management LLC disclaim beneficial ownership of securities held by Fairmount Healthcare Fund LP, except to the extent of their pecuniary interest therein. Fairmount Healthcare Fund II GP LLC and Fairmount Funds Management LLC disclaim beneficial ownership of securities held by Fairmount Healthcare Fund II LP, except to the extent of their pecuniary interest therein. The address of the Selling Stockholders is c/o Fairmount Funds Management LLC 2001 Market Street Suite 2500, Philadelphia, PA 19103.then current dividend period; or
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(8)•
Basedif that series of preferred stock does not have a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full dividends on information providedthe preferred stock of such series for the then current dividend period.
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However, at any time we may purchase or acquire preferred stock of that series (1) pursuant to a purchase or exchange offer made on the same terms to holders of all outstanding preferred stock of such series or (2) by conversion into or exchange for shares of our capital stock ranking junior to the Company bypreferred stock of such series as to dividends and upon liquidation.
If fewer than all of the Selling Stockholder. Consists of (i) 259,206outstanding shares of Common Stock issuedpreferred stock of any series are to be redeemed, we will determine the number of shares that may be redeemed pro rata from the holders of record of such shares in proportion to the number of such shares held or for which redemption is requested by such holder or by any other equitable manner that we determine. Such determination will reflect adjustments to avoid redemption of fractional shares.
Unless otherwise specified in the Merger and (ii) 3,928,000 sharesprospectus supplement, we will mail notice of Common Stock underlying 3,928 sharesredemption at least 10 days but not more than 60 days before the redemption date to each holder of Series X Preferred Stock issued inrecord of preferred stock to be redeemed at the Merger. The address of shown on our stock transfer books. Each notice shall state:
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the Selling Stockholder is 111 West Lemon Avenue, Monrovia, California 91016.redemption date;
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(9)•
Based on information providedthe number of shares and series of preferred stock to the Company by the Selling Stockholder. Consists of 5,174,000 shares of Common Stock underlying 5,174 shares of Series X Preferred Stock issued in the private placement. RA Capital Management, L.P. is the investment manager for RA Capital Healthcare Fund, L.P. The general partner of RA Capital Management, L.P. is RA Capital Management GP, LLC, of which Peter Kolchinsky and Rajeev Shah are the managing members. RA Capital Management, L.P., RA Capital Management GP, LLC, Peter Kolchinsky and Rajeev Shah may be deemed to have voting and investment power over the shares held of record by RA Capital Healthcare Fund, L.P. RA Capital Management, L.P., RA Capital Management GP, LLC, Peter Kolchinsky and Rajeev Shah disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein. The address of the entities listed above is 200 Berkeley Street, 18th Floor, Boston, Massachusetts 02116.redeemed;
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(10)•
Based on information provided to the Company by the Selling Stockholder. Consists of (i) 199,000 shares of Common Stock underlying 199 shares of Series X Preferred Stock issued to CRMA SPV LP (CRMA) in the private placement and (ii) 4,327,000 shares of Common Stock underlying 4,327 shares of Series X Preferred Stock issued to Cormorant Global Healthcare Master Fund LP (Cormorant Master Fund) in the private placement. Cormorant Global Healthcare GP, LLC (Global GP) is the general partner of Cormorant Hedge Fund. Bihua Chen serves as the managing member of Global GP and as the general partner of Cormorant Asset Management, LP (Cormorant). Cormorant serves as the investment manager to Cormorant Master Fund and CRMA. Ms. Chen is the natural person who exercises voting and dispositive power over the shares. The address of the Selling Stockholders is c/o Cormorant Asset Management, LP, 200 Clarendon Street, 52nd Floor, Boston, MA 02116.redemption price;
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(11)•
Basedthe place or places where certificates for such preferred stock are to be surrendered for payment of the redemption price;
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•
that dividends on information providedthe shares to be redeemed will cease to accrue on such redemption date;
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•
the Company bydate on which the Selling Stockholder. Consistsholder’s conversion rights, if any, as to such shares shall terminate; and
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•
the specific number of 3,234,000shares to be redeemed from each such holder if fewer than all the shares of Common Stock underlying 3,234 shares of Series X Preferred Stock issuedany series are to Logos Globalbe redeemed.
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Master Fund LPIf notice of redemption has been given and we have set aside the funds necessary for such redemption in trust for the benefit of the holders of any shares called for redemption, then from and after the redemption date, dividends will cease to accrue on such shares, and all rights of the holders of such shares will terminate, except the right to receive the redemption price.
Voting Rights.   Holders of preferred stock will not have any voting rights, except as required by law or as indicated in the private placement. Arsani William isapplicable prospectus supplement.
Unless otherwise provided for under the natural person who exercises voting and dispositive power over the shares. The addressterms of any series of preferred stock, no consent or vote of the Selling Stockholderholders of shares of preferred stock or any series thereof shall be required for any amendment to our certificate of incorporation that would increase the number of authorized shares of preferred stock or the number of authorized shares of any series thereof or decrease the number of authorized shares of preferred stock or the number of authorized shares of any series thereof (but not below the number of authorized shares of preferred stock or such series, as the case may be, then outstanding).
Conversion Rights.   The terms and conditions, if any, upon which any series of preferred stock is 1 Letterman Dr., Ste D-700, San Francisco, CA 94129.convertible into shares of our common stock will be set forth in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of common stock into which the shares of preferred stock are convertible, the conversion price, rate or manner of calculation thereof, the conversion period, provisions as to whether conversion will be at our option or at the option of the holders of the preferred stock, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption.
(12)Transfer Agent and Registrar.
   The transfer agent and registrar for the preferred stock will be set forth in the applicable prospectus supplement.
Based on information providedSeries X Preferred Stock
Pursuant to our Certificate of Designation of Preferences, Rights and Limitations of Series X Convertible Preferred Stock, or the CompanyCertificate of Designation, we designated 91,380 shares of our authorized and unissued preferred stock as Series X convertible preferred stock, or Series X Preferred Stock, and established the rights, preferences and privileges of the Series X Preferred Stock, which are summarized below. As of March 31, 2023, we had 31,107 outstanding shares of Series X Preferred Stock.
Conversion.   The Series X Preferred Stock is convertible at the option of the holder thereof into a number of registered shares of common stock determined by dividing the aggregate stated value of the Series X Preferred Stock being converted by the Selling Stockholders. Consistsconversion price then in effect. Each share of (i) 1,259,000Series X Preferred Stock is convertible into 166.67 shares of Common Stock underlying 1,259common stock. At March 31, 2023, the number of shares of common stock issuable upon conversion of the remaining outstanding shares of Series X Preferred Stock issued to Venrock Healthcare Capital Partners EG, L.P. in the private placement, (ii) 1,128,000 sharesis 5,184,591. No holder may request a conversion of Common Stock underlying 1,128 shares ofits Series X Preferred Stock issued to Venrock Healthcare Capital Partners III, L.P.the extent such conversion would result in the private placement, (iii) 113,000holder and its affiliates beneficially owning more than a pre-set conversion blocker threshold, which was initially set at 9.99% of our common stock then outstanding (as of March 31, 2023, these percentages are set at 9.99% and can be adjusted by the holder to a number between 4.99% and 19.99%). The amount of beneficial ownership of a holder and its affiliates will be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations of that section.
Conversion Price Adjustment  —  Stock Dividends and Stock Splits.   If we pay a stock dividend or otherwise make a distribution payable in common stock on our common stock or any common stock equivalents, subdivide or combine our outstanding common stock, or reclassify our common stock in such a way that we issue additional shares of Common Stock underlying 113 sharesour capital stock, the conversion price of the Series X Preferred Stock issued to VHCP Co-Investment Holdings III, LLC inwill be adjusted by multiplying the private placement, (iv) 522,000then-existing conversion price by a fraction, the numerator of which is the number of shares of Common Stock underlying 522common stock outstanding immediately before the distribution, dividend, adjustment or recapitalization and the denominator of which is the number of shares of common stock outstanding immediately after such action.
Fundamental Transaction.   If we effect a “fundamental transaction” ​(as defined below), then upon any future conversion of the Series X Preferred Stock, issued to Venrock Healthcare Capital Partners II, L.P. in the private placement and (v) 212,000 sharesa holder of Common Stock underlying 212 shares ofour Series X Preferred Stock issuedwill have the right to VHCP Co-Investment Holdings II, LLC inreceive, for each common share such holder would have received upon such conversion, the private placement. VHCP Management III, LLC (“VHCPM III”) is the sole general partner of Venrock Healthcare Capital Partners III, L.P. (“VHCP III”) and the sole manager of VHCP Co Investment Holdings III, LLC (“VHCP III Co”). VHCP Management II, LLC (“VHCPM II”) is the sole general partner of Venrock Healthcare Capital Partners II, L.P. (“VHCP II”) and the sole manager of VHCP Co Investment Holdings II, LLC (“VHCP II Co”). VHCP Management EG, LLC (“VHCPM EG”) is the sole general partner of Venrock Healthcare Capital Partners EG, L.P. (“VHCP EG”). Dr. Bong Koh and Nimish Shah are the voting members of VHCPM III, VHCPM II and VHCPM EG. Dr. Koh, Mr. Shah, VHCPM III, VHCPM II and VHCPM EG disclaim beneficial ownership over all shares held by VHCP III, VHCP III Co, VHCP II, VHCP II Co, and VHCP EG, except to the extent of their respective indirect pecuniary interests therein. The address of the Selling Stockholders is 7 Bryant Park, 23same kindrd Floor, New York, NY 10018.
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(13)
Based on information provided to the Company by the Selling Stockholders. Consists of (i) 1,775,000 shares of Common Stock underlying 1,775 shares of Series X Preferred Stock issued to Boxer Capital, LLC in the private placement and (ii) 165,000 shares of Common Stock underlying 165 shares of Series X Preferred Stock issued to MVA Investors, LLC in the private placement. Boxer Asset Management Inc. (“Boxer Management”) is the managing member and majority owner of Boxer Capital. Joe Lewis is the sole indirect beneficial owner of and controls Boxer Management. Boxer Management and Joseph C. Lewis may be deemed to have shared voting and dispositive power of the securities held by Boxer Capital, LLC. Aaron I. Davis is a member of and has voting and dispositive power over securities held by MVA Investors, LLC. The address of the Selling Stockholders is 12860 El Camino Real, Suite 300, San Diego, CA 92130.
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(14)
Based on information provided to the Company by the Selling Stockholder. Consists of 1,617,000 shares of Common Stock underlying 1,617 shares of Series X Preferred Stock issued in the private placement. The address of the Selling Stockholder is 420 Lexington Avenue, Suite 2626, New York, NY 10170.
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(15)
Based on information provided to the Company by the Selling Stockholder. Consists of 1,617,000 shares of Common Stock underlying 1,617 shares of Series X Preferred Stock issued in the private placement. The address of the Selling Stockholder is 767 Fifth Avenue, FL 12, New York, NY 10153.
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(16)
Based on information provided to the Company by the Selling Stockholder. Consists of 1,294,000 shares of Common Stock underlying 1,294 shares of Series X Preferred Stock issued in the private placement. Citadel Advisors LLC (“Citadel Advisors”) is the portfolio manager of Citadel Multi-Strategy Equities Master Fund Ltd. (“CEMF”). Citadel Advisors Holdings LP (“CAH”) is the sole member of Citadel Advisors. Citadel GP LLC (“CGP”) is the general partner of CAH. Kenneth Griffin owns a controlling interest in CGP. Mr. Griffin, as the owner of a controlling interest in CGP, may be deemed to have shared power to vote and/or shared power to dispose of the securities held by CEMF. The foregoing shall not be construed as an admission that Mr. Griffin nor any of the Citadel related entities listed above is the beneficial owner of any securities of the Company other than the securities actually owned by such person (if any). The address of CEMF is c/o Citadel Advisors LLC, 601 Lexington Avenue, New York, NY 10022.
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(17)
Based on information provided to the Company by the Selling Stockholder. Consists of (i) 1,074,000 shares of Common Stock underlying 1,074 shares of Series X Preferred Stock issued to Acuta Capital Fund, LP in the private placement and (ii) 220,000 shares of Common Stock underlying 220 shares of
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and amount of securities, cash or property as such holder would have been entitled to receive in the fundamental transaction had such holder been a holder of common stock immediately prior to the fundamental transaction.
The term “fundamental transaction” means any of the following:
•
a merger or consolidation of us with or into another entity or any stock sale to, or other business combination in which we are not the surviving entity;
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•
the sale of all or substantially all of our assets in one transaction or a series of related transactions;
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•
any completed tender offer or exchange offer involving holders of common stock in which more than 50% of our common stock is converted or exchanged into other securities, cash or property, regardless of who makes such offer; or
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•
any reclassification of our common stock or any compulsory share exchange by which our common stock is effectively converted into or exchanged for other securities, cash or property (but not a reverse stock split).
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If the holders of our common stock are given a choice as to the securities, cash or property to be received in a fundamental transaction, the holders of Series X Preferred Stock issuedwill be given the same choice on conversion of such holders’ shares.
Dividends.   Holders of Series X Preferred Stock are entitled to Acuta Opportunity Fund, LP in the private placement. Beneficialreceive dividends, subject to certain beneficial ownership includes (i) warrants to purchase 483,000 shares of Common Stock held by Acuta Capital Fund, LP and (ii) warrants to purchase 119,000 shares of Common Stock held by Acuta Capital Partners, LLC. Acuta Capital Partners, LLC exercises voting and dispositive power over the shares. The address of the Selling Stockholders is 1301 Shoreway Road, Ste. 350, Belmont, CA 94002.
(18)
Basedlimitations, on information provided to the Company by the Selling Stockholder. Consists of 1,294,000 shares of Common Stock underlying 1,294 shares of Series X Preferred Stock issuedequal, on an as-if-converted-to-common-stock basis, and in the private placement. The addresssame form as dividends actually paid on shares of the Selling Stockholder is 21 Ha’arbaa Street, 4th Floor, Tel Aviv, Israel.
​Company’s common stock.
(19)Voting Rights.
Based on information provided to   Except as otherwise required by law, the Company by the Selling Stockholder. Consists of 404,000 shares of CommonSeries X Preferred Stock underlying 404does not have voting rights. However, as long as any shares of Series X Preferred Stock issued inare outstanding, the private placement. Benjamin James Davey isCompany may not, without the natural person who exercises voting and dispositive power over the shares. The addressaffirmative vote of the Selling Stockholder is Wedbush Center, 1000 Wilshire Blvd., Los Angeles, CA 90017.
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(20)
Based on information providedholders of a majority of the then outstanding shares of the Series X Preferred Stock, (i) alter or change adversely the powers, preferences or rights given to the Company bySeries X Preferred Stock or alter or amend the Selling Stockholder. ConsistsCertificate of 243,000 sharesDesignation that authorized the Series X Preferred Stock, amend or repeal any provision of, Commonor add any provision to, the Company’s Certificate of Incorporation or bylaws, or file any articles of amendment, certificate of designations, preferences, limitations and relative rights of any series of preferred stock, if such action would adversely alter or change the preferences, rights, privileges or powers of, or restrictions provided for the benefit of the Series X Preferred Stock, underlying 243(ii) issue further shares of Series X Preferred Stock issued inor increase or decrease (other than by conversion) the private placement. Stewart J. Hen is the natural person who exercises voting and dispositive power over the shares. The addressnumber of the Selling Stockholder is 25 N. Moore Street #15A, New York, NY 10013.
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(21)
Based on information provided to the Company by the Selling Stockholder. Consists of (i) 2,805,000 shares of Common Stock underlying 2,805authorized shares of Series X Preferred Stock, issuable upon the exercise of warrants assumed by the Company and (ii) 185,136 shares of Common Stock issuable upon the exercise of warrants assumed by the Company. Jonathon Violin, a founder of Viridian, LLC, is a director of the Company. Peter Harwin is the natural person who exercises voting and dispositive power over the shares. The address of the Selling Stockholder is 203 Crescent Street, Bldg. #17, Suite #102B, Waltham, MA 02453.
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Relationship with the Selling Stockholders
Registration Rights Agreement
In addition to the Merger Agreement and Purchase Agreement, on January 28, 2021, we enteredor (iii) enter into a registration rightsany agreement with the Selling Stockholders who participated in the private placement (the “Registration Rights Agreement”). Pursuant to the Registration Rights Agreement, we agreed to prepare and file with the SEC a registration statement that permits the resale or other disposition of the Selling Stockholders’ Shares issued upon conversion of the Series X Preferred Stock issued to such Selling Stockholder pursuant to the Purchase Agreement and, subject to certain exceptions, use commercially reasonable efforts to keep the registration statement of which this prospectus forms a part effective under the Securities Act for so long as such securities registered for resale thereunder retain their character as Registrable Securities. We also agreed, among other things, to indemnify the Selling Stockholders, their officers, directors, members, employees and agents, successors and assigns under the registration statement from certain liabilities and pay all fees and expenses (excluding any legal fees of the Selling Stockholders, and any underwriting discounts and selling commissions) incident to our obligations under the Registration Rights Agreement.
Xencor License
Xencor, Inc. (“Xencor”) is party to a license agreement with Quellis, dated May 21, 2018, pursuant to which Xencor licensed to Quellis certain rights with respect to Xencor’s intellectual property.any of the foregoing.
Directors and Related PartiesStock Options
In connection with the Merger, on January 28, 2021, in exchangeAs of March 31, 2023, options to purchase 2,562,234 shares of our common stock at a weighted-average exercise price of $15.27 per share were outstanding, of which options to purchase 835,970 shares of our common stock were exercisable, at a weighted-average exercise price of $23.94 per share.
Warrants
As of March 31, 2023, we had outstanding warrants to purchase shares of our common stock exercisable for an aggregate of 350,0001,031,820 shares of Quellisour common stock at a weighted-average exercise price of $60.90 per share.
Provisions of Our Certificate of Incorporation and 1,245,447 sharesBy-laws and Delaware Law That May Have Anti-Takeover Effects
Delaware law, our certificate of Quellis preferred stock, (i) Perceptive Xontogeny Venture Fund, LP, a partnership inincorporation and our by-laws contain provisions that could have the effect of delaying, deferring or discouraging another party from acquiring control of us. These provisions, which Fred Callori, a directorare summarized below, are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of the Company, has an indirect pecuniary interest, received 1,933,551 sharesus to first negotiate with our board of Common Stock and 29,303 shares of Series X Preferred Stock and (ii) Xontogeny, LLC, a limited liability company in which Fred Callori has an indirect pecuniary interest, received 543,373 shares of Common Stock and 8,234 shares of Series X Preferred Stock. In connection with the Merger, on January 28, 2021, Fred Callori also received a grant of option to purchase 15,000 shares ofdirectors.
 
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Common Stock, which grant featuresStaggered Board; Removal of Directors.   Our certificate of incorporation and by-laws divide our board of directors into three classes with staggered three-year terms. In addition, a director is only able to be removed for cause and only by the affirmative vote of the holders of at least 75% of the votes that all of our stockholders would be entitled to cast in an exercise priceannual election of $2.43 per sharedirectors. Any vacancy on our board of directors, including a vacancy resulting from an enlargement of our board of directors, is only able to be filled by vote of a majority of our directors then in office. The classification of our board of directors and vests in equal 1/3 installmentsthe limitations on the first, secondremoval of directors and filling of vacancies could make it more difficult for a third anniversariesparty to acquire, or discourage a third party from seeking to acquire, control of our company.
Stockholder Action by Written Consent; Special Meetings.   Our certificate of incorporation provides that any action required or permitted to be taken by our stockholders must be effected at a duly called annual or special meeting of our stockholders and may not be effected by any consent in writing by our stockholders. Our certificate of incorporation and by-laws also provide that, except as otherwise required by law, special meetings of our stockholders can only be called by our chairman of the grant date.board, our chief executive officer or our board of directors.
In connectionAdvance Notice Requirements for Stockholder Proposals.   Our by-laws establish an advance notice procedure for stockholder proposals to be brought before an annual meeting of stockholders, including proposed nominations of persons for election to our board of directors. Stockholders at an annual meeting are only able to consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our board of directors or by a stockholder of record on the record date for the meeting who is entitled to vote at the meeting and who has delivered timely written notice in proper form to our secretary of the stockholder’s intention to bring such business before the meeting. These provisions could have the effect of delaying until the next stockholder meeting stockholder actions that are favored by the holders of a majority of our outstanding voting securities.
Delaware Business Combination Statute.   We are subject to Section 203 of the General Corporation Law of the State of Delaware. Subject to certain exceptions, Section 203 prevents a publicly held Delaware corporation from engaging in a “business combination” with any “interested stockholder” for three years following the date that the person became an interested stockholder, unless the interested stockholder attained such status with the Merger, (i) Lazarus Life Sciences I, LLC,approval of our board of directors or unless the business combination is approved in a limited liability company in which Jonathan Violin hasprescribed manner. A “business combination” includes, among other things, a merger or consolidation involving us and the “interested stockholder” and the sale of more than 10% of our assets. In general, an indirect interest, received 543,373 shares“interested stockholder” is any entity or person beneficially owning 15% or more of Common Stock and 8,234 shares of Series X Preferred Stock in exchange for an aggregate of 350,000 shares of Quellis commonour outstanding voting stock and (ii) Viridian, LLC, a limited liability company in which Jonathan Violin, a directorany entity or person affiliated with or controlling or controlled by such entity or person.
Amendment of Certificate of Incorporation and By-laws.   The General Corporation Law of the Company, holdsState of Delaware provides generally that the affirmative vote of a profits interest received warrants to purchase 185,136 shares of Common Stock and 2,805 shares of Series X Preferred Stock in exchange for a warrant to purchase 119,251 shares of Quellis common stock. The warrants are exercisable as to 52.1%majority of the shares subject theretoentitled to vote on any matter is required to amend a corporation’s certificate of incorporation or by-laws, unless a corporation’s certificate of incorporation or by-laws, as of January 21, 2021 and the remaining shares become exercisable atcase may be, requires a rate of 2.0833% each month thereafter until fully exercisable on December 21, 2022, subject to continued servicesgreater percentage. Our by-laws may be amended or repealed by a specified advisormajority vote of our board of directors or by the affirmative vote of the holders of at least 75% of the votes that all of our stockholders would be entitled to cast in any annual election of directors. In addition, the affirmative vote of the holders of at least 75% of the votes that all of our stockholders would be entitled to cast in any annual election of directors is required to amend or repeal or to adopt any provisions inconsistent with any of the provisions of our certificate of incorporation described above under “—  Staggered Board; Removal of Directors” and “—  Stockholder Action by Written Consent; Special Meetings.”
Exclusive Forum Selection.   Our certificate of incorporation provides that, unless we consent in writing to the Company through each vesting date. In connection withselection of an alternative forum, the Merger, on January 28, 2021, Jonathan Violin also received a grantCourt of option to purchase 15,000 shares of Common Stock, which grant features an exercise price of $2.43 per share and vests in equal 1/3 installments on the first, second and third anniversariesChancery of the grant date.State of Delaware (or if the Court of Chancery does not have jurisdiction, the federal district court for the District of Delaware) shall be the sole and exclusive forum for (1) any derivative action or proceeding brought on behalf of our company, (2) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers or employees to our company or our stockholders, (3) any action asserting a claim against our company arising pursuant to any provision of the General Corporation Law of the State of Delaware or our certificate of incorporation or by-laws, or (4) any action asserting a claim against our company governed by the internal affairs doctrine. This exclusive forum provision would not apply to suits brought to enforce any
 
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liability or duty created by the Securities Act or the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. To the extent that any such claims may be based upon federal law claims, Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. Furthermore, Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder. Although our restated certificate contains the choice of forum provision described above, it is possible that a court could rule that such a provision is inapplicable for a particular claim or action or that such provision is unenforceable. Although our certificate of incorporation contains the choice of forum provision described above, it is possible that a court could rule that such a provision is inapplicable for a particular claim or action or that such provision is unenforceable.
Authorized but Unissued Shares.   Our authorized but unissued shares of common stock and preferred stock are available for future issuance without stockholder approval, subject to any limitations imposed by the listing requirements of The Nasdaq Global Market. These additional shares may be used for a variety of corporate finance transactions, acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could make it more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

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DESCRIPTION OF DEPOSITARY SHARES
General
We may, at our option, elect to offer fractional shares of preferred stock, which we call depositary shares, rather than full shares of preferred stock. If we do, we will issue to the public receipts, called depositary receipts, for depositary shares, each of which will represent a fraction, to be described in the applicable prospectus supplement, of a share of a particular series of preferred stock. Unless otherwise provided in the prospectus supplement, each owner of a depositary share will be entitled, in proportion to the applicable fractional interest in a share of preferred stock represented by the depositary share, to all the rights and preferences of the preferred stock represented by the depositary share. Those rights include dividend, voting, redemption, conversion and liquidation rights.
The shares of preferred stock underlying the depositary shares will be deposited with a bank or trust company selected by us to act as depositary under a deposit agreement between us, the depositary and the holders of the depositary receipts. The depositary will be the transfer agent, registrar and dividend disbursing agent for the depositary shares.
The depositary shares will be evidenced by depositary receipts issued pursuant to the deposit agreement. Holders of depositary receipts agree to be bound by the deposit agreement, which requires holders to take certain actions such as filing proof of residence with and paying certain charges to the depositary.
The summary of terms of the depositary shares contained in this prospectus is not a complete description of the terms of the depositary shares. You should refer to the form of the deposit agreement, our certificate of incorporation and the certificate of designation for the applicable series of preferred stock that are, or will be, filed with the SEC.
Dividends and Other Distributions
The depositary will distribute all cash dividends or other cash distributions, if any, received in respect of the preferred stock underlying the depositary shares to the record holders of depositary shares in proportion to the numbers of depositary shares owned by those holders on the relevant record date. The relevant record date for depositary shares will be the same date as the record date for the underlying preferred stock.
If there is a distribution other than in cash, the depositary will distribute property (including securities) received by it to the record holders of depositary shares, unless the depositary determines that it is not feasible to make the distribution. If this occurs, the depositary may, with our approval, adopt another method for the distribution, including selling the property and distributing the net proceeds from the sale to the holders.
Liquidation Preference
If a series of preferred stock underlying the depositary shares has a liquidation preference, in the event of the voluntary or involuntary liquidation, dissolution or winding up of us, holders of depositary shares will be entitled to receive the fraction of the liquidation preference accorded each share of the applicable series of preferred stock, as set forth in the applicable prospectus supplement.
Withdrawal of Stock
Unless the related depositary shares have been previously called for redemption, upon surrender of the depositary receipts at the office of the depositary, the holder of the depositary shares will be entitled to delivery, at the office of the depositary to or upon his or her order, of the number of whole shares of the preferred stock and any money or other property represented by the depositary shares. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred stock to be withdrawn, the depositary will deliver to the holder at the same time a new depositary receipt evidencing the excess number of depositary shares. In no event will the depositary deliver fractional shares of preferred stock upon surrender of depositary receipts. Holders of preferred stock thus withdrawn may not thereafter deposit those shares under the deposit agreement or receive depositary receipts evidencing depositary shares therefor.

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Redemption of Depositary Shares
Whenever we redeem shares of preferred stock held by the depositary, the depositary will redeem as of the same redemption date the number of depositary shares representing shares of the preferred stock so redeemed, so long as we have paid in full to the depositary the redemption price of the preferred stock to be redeemed plus an amount equal to any accumulated and unpaid dividends on the preferred stock to the date fixed for redemption. The redemption price per depositary share will be equal to the redemption price and any other amounts per share payable on the preferred stock multiplied by the fraction of a share of preferred stock represented by one depositary share. If less than all the depositary shares are to be redeemed, the depositary shares to be redeemed will be selected by lot or pro rata or by any other equitable method as may be determined by the depositary.
After the date fixed for redemption, depositary shares called for redemption will no longer be deemed to be outstanding and all rights of the holders of depositary shares will cease, except the right to receive the monies payable upon redemption and any money or other property to which the holders of the depositary shares were entitled upon redemption upon surrender to the depositary of the depositary receipts evidencing the depositary shares.
Voting the Preferred Stock
Upon receipt of notice of any meeting at which the holders of the preferred stock are entitled to vote, the depositary will mail the information contained in the notice of meeting to the record holders of the depositary receipts relating to that preferred stock. The record date for the depositary receipts relating to the preferred stock will be the same date as the record date for the preferred stock. Each record holder of the depositary shares on the record date will be entitled to instruct the depositary as to the exercise of the voting rights pertaining to the number of shares of preferred stock represented by that holder’s depositary shares. The depositary will endeavor, insofar as practicable, to vote the number of shares of preferred stock represented by the depositary shares in accordance with those instructions, and we will agree to take all action that may be deemed necessary by the depositary in order to enable the depositary to do so. The depositary will not vote any shares of preferred stock except to the extent it receives specific instructions from the holders of depositary shares representing that number of shares of preferred stock.
Charges of Depositary
We will pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. We will pay the charges due to the depositary in connection with the initial deposit of the preferred stock and any redemption of the preferred stock. Holders of depositary receipts will pay transfer, income and other taxes and governmental charges and such other charges (including those in connection with the receipt and distribution of dividends, the sale or exercise of rights, the withdrawal of the preferred stock and the transferring, splitting or grouping of depositary receipts) as are expressly provided in the deposit agreement to be for their accounts. If these charges have not been paid by the holders of depositary receipts, the depositary may refuse to transfer depositary shares, withhold dividends and distributions and sell the depositary shares evidenced by the depositary receipt.
Amendment and Termination of the Deposit Agreement
The form of depositary receipt evidencing the depositary shares and any provision of the deposit agreement may be amended by agreement between us and the depositary. However, any amendment that materially and adversely alters the rights of the holders of depositary shares, other than fee changes, will not be effective unless the amendment has been approved by the holders of a majority of the outstanding depositary shares affected by the amendment. The deposit agreement may be terminated by the depositary or us only if:
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all outstanding depositary shares have been redeemed; or
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•
there has been a final distribution of the preferred stock in connection with our dissolution and such distribution has been made to all the holders of depositary shares.
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Resignation and Removal of Depositary
The depositary may resign at any time by delivering to us notice of its election to do so, and we may remove the depositary at any time. Any resignation or removal of the depositary will take effect upon our appointment of a successor depositary and its acceptance of such appointment. The successor depositary must be appointed within 60 days after delivery of the notice of resignation or removal and must be a bank or trust company having its principal office in the United States and having the requisite combined capital and surplus as set forth in the applicable agreement.
Notices
The depositary will forward to holders of depositary receipts all notices, reports and other communications, including proxy solicitation materials received from us, that are delivered to the depositary and that we are required to furnish to the holders of the preferred stock. In addition, the depositary will make available for inspection by holders of depositary receipts at the principal office of the depositary, and at such other places as it may from time to time deem advisable, any reports and communications we deliver to the depositary as the holder of preferred stock.
Limitation of Liability
Neither we nor the depositary will be liable if either we or it is prevented or delayed by law or any circumstance beyond its control in performing its obligations. Our obligations and those of the depositary will be limited to performance in good faith of our and their duties thereunder. We and the depositary will not be obligated to prosecute or defend any legal proceeding in respect of any depositary shares or preferred stock unless satisfactory indemnity is furnished. We and the depositary may rely upon written advice of counsel or accountants, on information provided by persons presenting preferred stock for deposit, holders of depositary receipts or other persons believed to be competent to give such information and on documents believed to be genuine and to have been signed or presented by the proper party or parties.

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DESCRIPTION OF UNITS
We may issue units comprised of one or more of the other securities that may be offered under this prospectus, in any combination. The following, together with the additional information we may include in the applicable prospectus supplement, summarizes the material terms and provisions of the units that we may offer under this prospectus. While the terms summarized below will apply generally to any units we may offer, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement.
Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately at any time, or at any time before a specified date.
Any applicable prospectus supplement will describe:
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the material terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;
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•
any material provisions relating to the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; and
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any material provisions of the governing unit agreement that differ from those described above.
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DESCRIPTION OF WARRANTS
We may issue warrants to purchase common stock, preferred stock or depositary shares. We may offer warrants separately or together with one or more additional warrants, common stock, preferred stock or depositary shares, or any combination of those securities in the form of units, as described in the applicable prospectus supplement. If we issue warrants as part of a unit, the accompanying prospectus supplement will specify whether those warrants may be separated from the other securities in the unit prior to the expiration date of the warrants. The applicable prospectus supplement will also describe the following terms of any warrants:
•
the specific designation and aggregate number of, and the offering price at which we will issue, the warrants;
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•
the currency or currency units in which the offering price, if any, and the exercise price are payable;
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the date on which the right to exercise the warrants will begin and the date on which that right will expire or, if you may not continuously exercise the warrants throughout that period, the specific date or dates on which you may exercise the warrants;
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•
whether the warrants are to be sold separately or with other securities as parts of units;
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•
whether the warrants will be issued in definitive or global form or in any combination of these forms, although, in any case, the form of a warrant included in a unit will correspond to the form of the unit and of any security included in that unit;
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any applicable material U.S. federal income tax consequences;
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the identity of the warrant agent for the warrants and of any other depositaries, execution or paying agents, transfer agents, registrars or other agents;
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•
the proposed listing, if any, of the warrants or any securities purchasable upon exercise of the warrants on any securities exchange;
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•
the designation and terms of any equity securities purchasable upon exercise of the warrants;
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if applicable, the designation and terms of the preferred stock or depositary shares with which the warrants are issued and the number of warrants issued with each security;
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•
if applicable, the date from and after which any warrants issued as part of a unit and the related preferred stock, depositary shares or common stock will be separately transferable;
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•
the number of shares of common stock, preferred stock or depositary shares purchasable upon exercise of a warrant and the price at which those shares may be purchased;
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•
if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;
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•
information with respect to book-entry procedures, if any;
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•
the anti-dilution provisions of, and other provisions for changes to or adjustment in the exercise price of, the warrants, if any;
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•
any redemption or call provisions; and
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any additional terms of the warrants, including terms, procedures and limitations relating to the exchange or exercise of the warrants.
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FORMS OF SECURITIES
Each depositary share, unit and warrant will be represented either by a certificate issued in definitive form to a particular investor or by one or more global securities representing the entire issuance of securities. Unless the applicable prospectus supplement provides otherwise, certificated securities in definitive form and global securities will be issued in registered form. Definitive securities name you or your nominee as the owner of the security, and in order to transfer or exchange these securities or to receive payments other than interest or other interim payments, you or your nominee must physically deliver the securities to the trustee, registrar, paying agent or other agent, as applicable. Global securities name a depositary or its nominee as the owner of the depositary shares, units or warrants represented by these global securities. The depositary maintains a computerized system that will reflect each investor’s beneficial ownership of the securities through an account maintained by the investor with its broker/dealer, bank, trust company or other representative, as we explain more fully below.
Global Securities
We may issue the depositary shares, units and warrants in the form of one or more fully registered global securities that will be deposited with a depositary or its nominee identified in the applicable prospectus supplement and registered in the name of that depositary or nominee. In those cases, one or more global securities will be issued in a denomination or aggregate denominations equal to the portion of the aggregate principal or face amount of the securities to be represented by global securities. Unless and until it is exchanged in whole for securities in definitive registered form, a global security may not be transferred except as a whole by and among the depositary for the global security, the nominees of the depositary or any successors of the depositary or those nominees.
If not described below, any specific terms of the depositary arrangement with respect to any securities to be represented by a global security will be described in the prospectus supplement relating to those securities. We anticipate that the following provisions will apply to all depositary arrangements.
Ownership of beneficial interests in a global security will be limited to persons, called participants, that have accounts with the depositary or persons that may hold interests through participants. Upon the issuance of a global security, the depositary will credit, on its book-entry registration and transfer system, the participants’ accounts with the respective principal or face amounts of the securities beneficially owned by the participants. Any dealers, underwriters or agents participating in the distribution of the securities will designate the accounts to be credited. Ownership of beneficial interests in a global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary, with respect to interests of participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some states may require that some purchasers of securities take physical delivery of these securities in definitive form. These laws may impair your ability to own, transfer or pledge beneficial interests in global securities.
So long as the depositary, or its nominee, is the registered owner of a global security, that depositary or its nominee, as the case may be, will be considered the sole owner or holder of the securities represented by the global security for all purposes under the applicable deposit agreement, unit agreement or warrant agreement. Except as described below, owners of beneficial interests in a global security will not be entitled to have the securities represented by the global security registered in their names, will not receive or be entitled to receive physical delivery of the securities in definitive form and will not be considered the owners or holders of the securities under the applicable deposit agreement, unit agreement or warrant agreement. Accordingly, each person owning a beneficial interest in a global security must rely on the procedures of the depositary for that global security and, if that person is not a participant, on the procedures of the participant through which the person owns its interest, to exercise any rights of a holder under the applicable deposit agreement, unit agreement or warrant agreement. We understand that under existing industry practices, if we request any action of holders or if an owner of a beneficial interest in a global security desires to give or take any action that a holder is entitled to give or take under the applicable deposit agreement, unit agreement or warrant agreement, the depositary for the global security would authorize the participants holding the relevant beneficial interests to give or take that action, and the participants would authorize beneficial owners owning through them to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them.

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Any payments to holders with respect to depositary shares, units or warrants represented by a global security registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the global security. None of us, or any warrant agent, unit agent or other agent of ours, or any agent of any warrant agent or unit agent will have any responsibility or liability for any aspect of the records relating to payments made on account of beneficial ownership interests in the global security or for maintaining, supervising or reviewing any records relating to those beneficial ownership interests.
We expect that the depositary for any of the securities represented by a global security, upon receipt of any payment to holders or other distribution of underlying securities or other property on that registered global security, will immediately credit participants’ accounts in amounts proportionate to their respective beneficial interests in that global security as shown on the records of the depositary. We also expect that payments by participants to owners of beneficial interests in a global security held through participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers or registered in “street name,” and will be the responsibility of those participants.
If the depositary for any of the securities represented by a global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act, and a successor depositary registered as a clearing agency under the Exchange Act is not appointed by us within 90 days, we will issue securities in definitive form in exchange for the global security that had been held by the depositary. Any securities issued in definitive form in exchange for a global security will be registered in the name or names that the depositary gives to the relevant warrant agent, unit agent or other relevant agent of ours or theirs. It is expected that the depositary’s instructions will be based upon directions received by the depositary from participants with respect to ownership of beneficial interests in the global security that had been held by the depositary.

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PLAN OF DISTRIBUTION
We are registering the Shares issued to the Selling Stockholders to permit the resale of these Shares by the holders of the Shares from time to time after the date of this prospectus. We will not receive any of the proceeds from the sale by the Selling Stockholders of the Shares. We will, or will procure to, bear all fees and expenses incident to our obligation to register the Shares.
The Selling Stockholders may sell all or a portion of the Shares beneficially owned by them and offered hereby from time to time directly or through one or more underwriters, broker-dealers or agents. If the Shares are sold through underwriters or broker-dealers, the Selling Stockholders will be responsible for underwriting discounts or commissions or agent’s commissions. The Shares may be sold on any national securities exchange or quotation service on which the securities may be listed or quoted at the time of sale, in the over-the-counter market or in transactions otherwise than on these exchanges or systems or in the over-the-counter market and in one or more transactions at fixed prices, at prevailing market prices at the time of the sale, at varying prices determined at the time of sale, or at negotiated prices. These sales may be effected in transactions, which may involve crosses or block transactions. The Selling Stockholders may use any one or more of the following methods when selling shares:securities:
•
ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;
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block trades in which the broker-dealer will attempt to sell the shares as agent but may position and resell a portion of the block as principal to facilitate the transaction;
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•
purchases by a broker-dealer as principal and resale by the broker-dealer for its account;
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•
an exchange distribution in accordance with the rules of the applicable exchange;
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privately negotiated transactions;
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•
settlement of short sales;
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broker-dealers may agree with the Selling Stockholders to sell a specified number of such shares at a stipulated price per share;through underwriters;
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•
through the writing or settlement of options or other hedging transactions, whether such options are listed on an options exchange or otherwise;dealers;
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through agents;
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directly to purchasers; or
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•
through a combination of any suchof these methods of sale.
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In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing security holders. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.
We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers. We will, in the prospectus supplement relating to such offering, name any agent that could be viewed as an underwriter under the Securities Act, and describe any commissions that we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis.
The distribution of the securities may be effected from time to time in one or more transactions:
•
at a fixed price, or prices, which may be changed from time to time;
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•
at market prices prevailing at the time of sale;
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•
at prices related to such prevailing market prices; or
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•
at negotiated prices.
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Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.
The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:
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the name of the agent or any underwriters;
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the public offering or purchase price and the proceeds we will receive from the sale of the securities;
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any discounts and commissions to be allowed or re-allowed or paid to the agent or underwriters;
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all other items constituting underwriting compensation;
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any discounts and commissions to be allowed or re-allowed or paid to dealers; and
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any other method permitted pursuant to applicable law.exchanges on which the securities will be listed.
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The Selling Stockholders also may resell allIf any underwriters or a portionagents are utilized in the sale of the sharessecurities in open market transactions in reliance upon Rule 144 under the Securities Act, as amended, or the Securities Act, as permitted by that rule, or Section 4(a)(1) under the Securities Act, if available, rather than underrespect of which this prospectus provided that they meetis delivered, we will enter into an underwriting agreement or other agreement with them at the criteriatime of sale to them, and conform to the requirements of those provisions.
Broker-dealers engaged by the Selling Stockholders may arrange for other broker-dealers to participate in sales. If the Selling Stockholders effect such transactions by selling Shares to or through underwriters, broker-dealers or agents, such underwriters, broker-dealers or agents may receive commissions in the form of discounts, concessions or commissions from the Selling Stockholders or commissions from purchasers of the Shares for whom they may act as agent or to whom they may sell as principal. Such commissionswe will be in amounts to be negotiated, but, except as set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.
If a supplement to this Prospectus,dealer is utilized in the case of an agency transaction will not be in excess of a customary brokerage commission in compliance with FINRA Rule 2121; and in the case of a principal transaction a markup or markdown in compliance with FINRA IM-2121.01.
In connection with salessale of the Shares or otherwise,securities in respect of which this prospectus is delivered, we will sell such securities to the Selling Stockholdersdealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.
If we offer securities in a subscription rights offering to our existing security holders, we may enter into hedging transactionsa standby underwriting agreement with broker-dealers or other financial institutions, whichdealers, acting as standby underwriters. We may in turn engage in short sales ofpay the Shares instandby underwriters a commitment fee for the course of hedging in positionssecurities they assume. The Selling Stockholderscommit to purchase on a standby basis. If we do not enter into a standby underwriting arrangement, we may also sell Shares short and if such short sale shall take place after the date that this Registration Statement is declared effective by the Commission, the Selling Stockholders may deliver Shares covered by this prospectusretain a dealer-manager to close out short positions and to return borrowed shares in connection with such short sales. The Selling Stockholders may also loan or pledge Shares to broker-dealers that in turn may sell such shares, to the extent permittedmanage a subscription rights offering for us.
 
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by applicable law. The Selling StockholdersRemarketing firms, agents, underwriters, dealers and other persons may alsobe entitled under agreements which they may enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the deliveryus to such broker-dealer or other financial institution of shares offeredindemnification by this prospectus, which shares such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).
The Selling Stockholders may, from time to time, pledge or grant a security interest in some or all of the Shares owned by them and, if they default in the performance of their secured obligations, the pledgees or secured parties may offer and sell the Shares from time to time pursuant to this prospectus or any amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act of 1933, amending, if necessary, the list of Selling Stockholders to include the pledgee, transferee or other successors in interest as Selling Stockholders under this prospectus. The Selling Stockholders also may transfer and donate the Shares in other circumstances, with or without cash consideration, in which case the transferees, donees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.
The Selling Stockholders and any broker-dealer or agents participating in the distribution of the Shares may be deemed to be “underwriters” within the meaning of Section 2(11) of the Securities Act in connection with such sales. In such event, any commissions paid, or any discounts or concessions allowed to, any such broker-dealer or agent and any profit on the resale of the shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. Selling Stockholders who are “underwriters” within the meaning of Section 2(11) of the Securities Act will be subject to the applicable prospectus delivery requirements of the Securities Act including Rule 172 thereunder and may be subject to certain statutory liabilities of, including but not limited to, Sections 11, 12 and 17 of the Securities Act and Rule 10b-5 under the Securities Exchange Act of 1934, as amended, or the Exchange Act.
Each Selling Stockholder has informed the Company that it is not a registered broker-dealer and does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the Shares. Upon the Company being notified in writing by a Selling Stockholder that any material arrangement has been entered into with a broker-dealer for the sale of Common Stock through a block trade, special offering, exchange distribution or secondary distribution or a purchase by a broker or dealer, a supplement to this prospectus will be filed, if required, pursuant to Rule 424(b) under the Securities Act, disclosing (i) the name of each such Selling Stockholder and of the participating broker-dealer(s), (ii) the number of shares involved, (iii) the price at which such the Shares were sold, (iv) the commissions paid or discounts or concessions allowed to such broker-dealer(s), where applicable, (v) that such broker-dealer(s) did not conduct any investigation to verify the information set out or incorporated by reference in this prospectus, and (vi) other facts material to the transaction. In no event shall any broker-dealer receive fees, commissions and markups, which, in the aggregate, would exceed eight percent (8.0%).
Under the securities laws of some U.S. states, the Shares may be sold in such states only through registered or licensed brokers or dealers. In addition, in some U.S. states the Shares may not be sold unless such shares have been registered or qualified for sale in such state or an exemption from registration or qualification is available and is complied with.
There can be no assurance that any Selling Stockholder will sell any or all of the Shares registered pursuant to the shelf registration statement, of which this prospectus forms a part.
Each Selling Stockholder and any other person participating in such distribution will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including, without limitation, to the extent applicable, Regulation M of the Exchange Act, which may limit the timing of purchases and sales of any of the Shares by the Selling Stockholders and any other participating person. To the extent applicable, Regulation M may also restrict the ability of any person engaged in the distribution of the Shares to engage in market-making activities with respect to the Shares. All of the foregoing may affect the marketability of the Shares and the ability of any person or entity to engage in market-making activities with respect to the Shares.
We will pay all expenses of the registration of the Shares pursuant to the registration rights agreement, including, without limitation, Securities and Exchange Commission filing fees and expenses of compliance

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with state securities or “blue sky” laws; provided, however, that each Selling Stockholder will pay all underwriting discounts and selling commissions, if any and any related legal expenses incurred by it. We will indemnify the Selling Stockholdersus against certain liabilities, including some liabilities under the Securities Act, in accordance with the registration rights agreement, or the Selling Stockholders will be entitled to contribution. We may be indemnified by the Selling Stockholders against civil liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.
If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:
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the purchase by an institution of the securities covered under that contract shall not at the time of delivery be prohibited under the laws of the jurisdiction to which that institution is subject; and
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if the securities are also being sold to underwriters acting as principals for their own account, the underwriters shall have purchased such securities not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.
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Certain agents, underwriters and dealers, and their associates and affiliates may arise frombe customers of, have borrowing relationships with, engage in other transactions with, and/or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.
In order to facilitate the offering of the securities, any written information furnishedunderwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to us by the Selling Stockholders specifically for usedetermine payments on such securities. Specifically, any underwriters may overallot in this prospectus, in accordanceconnection with the related registration rights agreements,offering, creating a short position for their own accounts. In addition, to cover overallotments or weto stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.
Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise or the securities are sold by us to an underwriter in a firm commitment underwritten offering. The applicable prospectus supplement may provide that the original issue date for your securities may be entitledmore than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to contribution.trade securities on any date prior to the second business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than two scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.
The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.
 
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LEGAL MATTERS
TheUnless the applicable prospectus supplement indicates otherwise, the validity of the securities in respect of which this prospectus is being delivered will be passed upon for us by Wilmer Cutler Pickering Hale and Dorr LLP, Boston, Massachusetts.LLP. Additional legal matters may be passed upon for us or any underwriters, dealer or agents, by counsel that we will name in the applicable prospectus supplement.
EXPERTS
Ernst & Young, LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2020,2022, as set forth in their report, (which contains an explanatory paragraph describing conditions that raise substantial doubt about the Company’s ability to continue as a going concern as described in Note 1 to the consolidated financial statements), which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s report, given on their authority as experts in accounting and auditing.
WHERE YOU CAN FIND MORE INFORMATION
We file reports, proxy statements and other documents with the SEC. You may read and copy any document we file at the SEC’s public reference room at 100 F Street, N.E., Washington, D.C. 20549. You should call 1-800-SEC-0330 for more information on the public reference room. Our SEC filings are also available to you on the SEC’s Internet site at www.sec.gov.
This prospectus is part of a registration statement that we filed with the SEC. The registration statement contains more information than this prospectus regarding us and our common stock, including certain exhibits and schedules. You can obtain a copy of the registration statement from the SEC at the address listed above or from the SEC’s Internet site.
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
The SEC allows us to “incorporate by reference” into this prospectus the information we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings made with the SEC under Sections 13(a), 13(c), 14, or 15(d) of the Securities Exchange Act of 1934 subsequent to the date of this registration statement until the end of any offerings under this prospectus:
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Our Annual Report on Form 10-K for the fiscal year ended December 31, 2020 filed with the SEC on March 11, 2021, including the information specifically incorporated by reference into the Annual Report on Form 10-K from our definitive proxy statement for the 2021 Annual Meeting of Stockholders;
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Our Current Reportson Form 8-K dated January 29, 2021 and April 16, 2021;
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The description of our common stock contained in our Registration Statement on Form 8-A filed with the SEC on June 23, 2015, as well as any subsequent amendments or reports filed for the purpose of updating such description; and
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All documents filed by the Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, after the date of the original Registration Statement and prior to effectiveness of the registration statement of which this prospectus is a part, provided that all documents “furnished” by the Company to the SEC and not “filed” are not deemed incorporated by reference herein.
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You should rely only on the information incorporated by reference or provided in this prospectus or any prospectus supplement. We have not authorized anyone else to provide you with different information. You should not assume that the information in this prospectus or any prospectus supplement is accurate as of any date other than the date on the front page of those documents.
Notwithstanding the foregoing, unless specifically stated to the contrary, information that we furnish (and that is not deemed “filed” with the SEC) under Items 2.02 and 7.01 of any Current Report on Form 8-K,

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including the related exhibits under Item 9.01, is not incorporated by reference into this prospectus or the registration statement of which this prospectus is a part.
We will furnish without charge to you, on written or oral request, a copy of any or all of the documents incorporated by reference in this prospectus, including exhibits to these documents. You should direct any requests for documents to Catabasis Pharmaceuticals, Inc., 100 High Street, 28th Floor, Boston, Massachusetts 02110, telephone (617) 394-1971.
 
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CATABASIS PHARMACEUTICALS,ASTRIA THERAPEUTICS, INC.​
92,399,805 Shares of $250,000,000​
Common Stock
Offered by the Selling StockholdersPreferred Stock

Depositary Shares
Units
Warrants​
PROSPECTUS
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         , 20212023
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PART II
INFORMATION NOT REQUIRED IN PROSPECTUS
Item 14.
Other Expenses of Issuance and Distribution.
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The following table setsSet forth below are estimates (except in the variouscase of the SEC registration fee) of the amount of fees and expenses to be incurred in connection with the saleissuance and distribution of the offered securities, being registered hereby, all of which will be borne by Catabasis Pharmaceuticals, Inc. (except anyother than underwriting discounts and commissionscommissions.
​SEC registration fee.​​​$27,550​​
​FINRA filing fee​​​$​(1)​​
​Printing and engraving​​​$​(1)​​
​Accounting services​​​$​(1)​​
​Legal fees of registrant’s counsel.​​​$​(1)​​
​Miscellaneous​​​$​(1)​​
​Total​​​$​(1)​​
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(1)
These fees and expenses incurred byare calculated based on the Selling Stockholders for brokerage, accounting, tax or legal services or any other expenses incurred bysecurities offered and the Selling Stockholdersnumber of issuances and accordingly are not estimated at this time and will be reflected in disposing of the shares). All amounts shown are estimates except the SEC registration fee.applicable prospectus supplement.
​Registration Fee – Securities and Exchange Commission​​​$27,117​​
​Accountants Fees and Expenses​​​$5,000​​
​Legal Fees and Expenses​​​$100,000​​
​Miscellaneous​​​$5,000​​
​Total​​​$137,117​​
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Item 15.
Indemnification of Directors and Officers.
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Section 102 of the Delaware General Corporation Law allows a corporation to eliminate the personal liability of directors of a corporation to the corporation or its stockholders for monetary damages for a breach of fiduciary duty as a director, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. Catabasis Pharmaceuticals, Inc. has included such a provision in its Certificate of Incorporation.
Section 145 of the General Corporation Law of the State of Delaware (“DGCL”) provides, generally, that a corporation hasshall have the power to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding (except actions by or in the right of the corporation) by reason of the fact that such person is or was a director, officer, employee or agent of the corporation against all expenses, judgments, fines and certain other persons serving at the request of the corporation in related capacities against amounts paid in settlement actually and expensesreasonably incurred by such person in connection with ansuch action, suit or proceeding to which he is or is threatened to be made a party by reason of such position, if such person shall have acted in good faith and in a manner such person reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful. A corporation may similarly indemnify such person for expenses actually and reasonably incurred by such person in connection with the defense or settlement of any action or suit by or in the right of the corporation, provided that such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal proceeding, if such person had no reasonable cause to believe his conduct was unlawful; provided that, in the case of actions brought by or in the right of the corporation, no indemnification shall be made with respect to any matterclaims, issues and matters as to which such person shall have been adjudged to be liable to the corporation, unlessprovided that a court shall have determined, upon application, that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and onlyreasonably entitled to indemnity for such expenses which such court shall deem proper.
Section 102(b)(7) of the DGCL provides, generally, that our certificate of incorporation may contain a provision eliminating or limiting the personal liability of a director or officer to the extent that the adjudicating court determinescorporation or its stockholders for monetary damages for breach of fiduciary duty as a director or officer, provided that such indemnification is properprovision may not eliminate or limit the liability of (i) a director or officer for any breach of the director’s or officer’s duty of loyalty to the corporation or its stockholders, (ii) a director or officer for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) a director under section 174 of the circumstances.DGCL, (iv) a director or officer for any transaction from which the director or officer derived an improper personal benefit or (v) an officer in any action by or in the right of the corporation. No such provision may eliminate or limit the liability of a director or officer for any act or omission occurring prior to the date when such provision became effective.
Our certificate of incorporation provides that no director shall be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duty as a director, notwithstanding any provision of law imposing such liability, except to the extent that the DGCL prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty. Our board of directors has approved an

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amendment to our certificate of incorporation, the effectiveness of which is subject to stockholder approval at our 2023 annual meeting of stockholders, to update our existing director exculpation provision to include exculpation of our corporate officers. The amendment, if approved, would provide that no officer shall be personally liable to our stockholders for monetary damages for any breach of fiduciary duty as an officer, notwithstanding any provision of law imposing such liability, except to the extent that the DGCL prohibits the elimination or limitation of liability of officers for breaches of fiduciary duty. Our certificate of incorporation also provides that we will indemnify each person who was or is a party or threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of us), by reason of the fact that he or she is or was, or has agreed to become, our director or officer, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise (all such persons being referred to as an Indemnitee), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding and any appeal therefrom if such Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, our best interests, and, with respect to any criminal action or proceeding, he or she had no reasonable cause to believe his or her conduct was unlawful.
Our certificate of incorporation also provides that we will indemnify any Indemnitee who was or is a party to an action or suit by or in the right of us to procure a judgment in our favor by reason of the fact that the Indemnitee is or was, or has agreed to become, our director or officer, or is or was serving, or has

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agreed to serve, at our request as a director, officer, partner, employee or trustee or, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise, or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys’ fees) and, to the extent permitted by law, amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding, and any appeal therefrom, if the Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, our best interests, except that no indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to us, unless a court determines that, despite such adjudication but in view of all of the circumstances, he or she is entitled to indemnification of such expenses. Notwithstanding the foregoing, to the extent that any Indemnitee has been successful, on the merits or otherwise, he or she will be indemnified by us against all expenses (including attorneys’ fees) actually and reasonably incurred by him or her or on his or her behalf in connection therewith. If we do not assume the defense, expenses must be advanced to an Indemnitee under certain circumstances.
We have entered into indemnification agreements with our directors and executive officers. In general, these agreements provide that we will indemnify the director or executive officer to the fullest extent permitted by law for claims arising in his or her capacity as a director or officer of our company or in connection with their service at our request for another corporation or entity. The indemnification agreements also provide for procedures that will apply in the event that a director or executive officer makes a claim for indemnification and establish certain presumptions that are favorable to the director or executive officer.
We maintain a general liability insurance policy that covers certain liabilities of our directors and officers arising out of claims based on acts or omissions in their capacities as directors or officers.
In any underwriting agreement we enter into in connection with the sale of securities being registered hereby, the underwriters will agree to indemnify, under certain conditions, us, our directors and officers (as well as certain other persons) against certain liabilities arising in connection with such offering.
Insofar as the forgoing provisions permit indemnification of directors, executive officers, or persons controlling us for liability arising under the Securities Act of 1933, as amended, or the Securities Act, we have been informed that, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

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Item 16.
ExhibitsExhibits.
​
​
Exhibit
No.
​​Description​
​1*​​Form of Underwriting Agreement​
​4.1​​Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.2 to the Registrant’s Current Report on Form 8-K (File No. 001-37467) filed with the SEC on September 8, 2021)​
​4.2​​Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.3 to the Registrant’s Current Report on Form 8-K (File No. 001-37467) filed with the SEC on September 8, 2021)​
​4.3*​​Form of Deposit Agreement​
​4.4*​​Form of Warrant Agreement​
​4.5*​​Form of Unit Agreement​
​5.1​​
Opinion of Wilmer Cutler Pickering Hale and Dorr LLP
​
​23.1​​
Consent of Ernst & Young LLP, independent registered public accounting firm for the Registrant
​
​23.2​​
Consent of Wilmer Cutler Pickering Hale and Dorr LLP (included in Exhibit 5.1)
​
​24 ​​
Powers of Attorney (included in the signature pages to the Registration Statement)
​
​107 ​​
Filing Fee Table
​
A list of exhibits
​
*
To be filed with this registration statementby amendment or by a Current Report on Form S-3 is set forth on the Exhibit Index and is incorporated herein by reference.8-K.
​
Item 17.
Undertakings.Undertakings
​
Item 512(a) of Regulation S-K.   The undersigned registrantRegistrant hereby undertakes:
(a)(1)
To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:
​
(i)   To
to include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;1933, as amended (the “Securities Act”);
​
(ii)   To
to reflect in the prospectus any facts or events arising after the effective date of thethis registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in thethis registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and
​
(iii)   To
to include any material information with respect to the plan of distribution not previously disclosed in thethis registration statement or any material change to such information in thethis registration statement;
​

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Provided, , however, That:
Paragraphsthat paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrantRegistrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), that are incorporated by reference in thethis registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of thethis registration statement.

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(2)
That, for the purposepurposes of determining any liability under the Securities Act, of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at thatthe time shall be deemed to be the initial bona fide offering thereof.
​
(3)
To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.
​
(4)
That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:
​
(A) Each(i)
each prospectus filed by the registrantRegistrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in thisthe registration statement; and
​
(B) Each(ii)
each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.thereof; Provided,provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of this Registration Statementthe registration statement or made in any such document immediately prior to such effective date.
​
Item 512(b)(5)
That, for the purpose of Regulation S-Kdetermining liability of the Registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:
​
(i)
any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 424;
​
(ii)
any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used or referred to by the undersigned Registrant;
​
(iii)
the portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and
​
(iv)
any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.
​
(6)
That, for purposes of determining any liability under the Securities Act:
​
(i)
the information omitted from the form of prospectus filed as part of the registration statement in reliance upon Rule 430A and contained in the form of prospectus filed by
​

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the Registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of the registration statement as of the time it was declared effective; and
(ii)
each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial .bona fide offering thereof.
​
(b)   The undersigned registrantRegistrant hereby undertakes that, for purposes of determining any liability under the Securities Act, of 1933, each filing of the registrant’sRegistrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934, as amended (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934)Act) that is incorporated by reference in thethis registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
Item 512(h) of Regulation S-K.(c)   Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrantRegistrant pursuant to the foregoingindemnification provisions described herein, or otherwise, the registrantRegistrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrantRegistrant of expenses incurred or paid by a director, officer or controlling person of the registrantRegistrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrantRegistrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.
 
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EXHIBIT INDEX
Exhibit No.​​Description​
 2.1​​Agreement and Plan of Merger, dated January 28, 2021, by and among Catabasis Pharmaceuticals, Inc., Cabo Merger Sub I, Inc., Cabo Merger Sub II, LLC and Quellis Biosciences, Inc. (incorporated by reference to Exhibit 2.1 to the Registrant’s Current Report on Form 8-K (File No. 001-36620) filed on January 29, 2021)​
 3.1​​Certificate of Designations of Series X Convertible Preferred Stock (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (File No. 001-36620) filed on January 29, 2021)​
 4.1​​Specimen stock certificate evidencing the shares of common stock (incorporated by reference to Exhibit 4.1 to the Registrant’s Registration Statement on Form S-1 (File No. 333-204144) filed on June 11, 2015)​
 4.2​​Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (File No. 001-37467) filed on July 1, 2015)​
 4.3​​Certificate of Amendment to Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (File No. 001-37467) filed on December 31, 2018)​
 4.4​​
Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.2 to the Registrant’s Current Report on Form 8-K (File No. 001-37467) filed on July 1, 2015)
​
 5.1**​​
Opinion of Wilmer Cutler Pickering Hale and Dorr LLP
​
10.1​​Stock Purchase Agreement, dated as of January 28, 2021, by and among Catabasis Pharmaceuticals, Inc. and each purchaser identified on Annex A thereto (incorporated by reference to Exhibit 10.1 to the Registrant’s Current Report on Form 8-K (File No. 001-37467) filed on January 29, 2021)​
10.2​​Registration Rights Agreement, by and among Catabasis Pharmaceuticals, Inc. and certain purchasers named therein (incorporated by reference to Exhibit 10.3 to the Registrant’s Annual Report on Form 10-K (File No. 001-37467) filed on March 11, 2021)​
23.1*​​
Consent of Ernst & Young LLP, independent registered public accounting firm
​
23.2**​​
Consent of Wilmer Cutler Pickering Hale and Dorr LLP (included in legal opinion filed as Exhibit 5.1)
​
24.1**​​
Power of Attorney (included on signature page)
​
​
*
Filed herewith.
​
**
Previously filed.
​

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SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, as amended, the registrantRegistrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statementRegistration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Boston,Cambridge, Commonwealth of Massachusetts, on April 16, 2021.this 11th day of May 2023.
CATABASIS PHARMACEUTICALS,ASTRIA THERAPEUTICS, INC.
By:
/s/ JillJILL C. MilneMILNE
​
​
Name: Jill C. Milne, Ph.D.
Title:  President and Chief Executive Officer
SIGNATURES AND POWER OF ATTORNEY
We, the undersigned officers and directors of Astria Therapeutics, Inc. hereby severally constitute and appoint Jill C. Milne, Benjamin Harshbarger and Noah Clauser, and each of them singly, our true and lawful attorneys with full power to any of them, and to each of them singly, to sign for us and in our names in the capacities indicated below the Registration Statement on Form S-3 filed herewith and any and all amendments (including post-effective amendments) to said Registration Statement, and any registration statement filed pursuant to Rule 462 under the Securities Act of 1933, as amended, in connection with said Registration Statement, and to file or cause to be filed the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, and generally to do all such things in our name and on our behalf in our capacities as officers and directors to enable Astria Therapeutics, Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming all that said attorneys, and each of them, or their substitute or substitutes, shall do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.
​Signature​​Title​​Date​
​
/s/ JillJILL C. MilneMILNE
​
Jill C. Milne
​​President and Chief Executive Officer and Director
(Principal (Principal Executive Officer)Officer		​​April 16, 2021May 11, 2023​
​
/s/ Noah ClauserNOAH CLAUSER
​
Noah Clauser
​​Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)​​April 16, 2021May 11, 2023​
​
*/s/ KENNETH BATE
​
Kenneth Bate
​​Director, Chair of the Board of DirectorsChairman​​April 16, 2021May 11, 2023​
​
*/s/ JOANNE BECK
​
Joanne T. Beck
​​Director​​April 16, 2021May 11, 2023​
​
*/s/ FREDERICK C. CALLORI
​
FredFrederick C. Callori
​​Director​​April 16, 2021May 11, 2023​
​
*/s/ HUGH COLE
​
Hugh M. Cole
​​Director​​April 16, 2021May 11, 2023​

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​Signature​​Title​​Date​
​
*/s/ MICHAEL KISHBAUCH
​
Michael Kishbauch
​​Director​​May 11, 2023​
​
/s/ GREGG LAPOINTE
​
Gregg Lapointe
​​Director​​April 16, 2021May 11, 2023​
​
*
​
Michael D. Kishbauch
​​Director​​April 16, 2021​
​
*/s/ JONATHAN VIOLIN
​
Jonathan Violin
​​Director​​April 16, 2021​
​
*By /s/ Ben Harshbarger
​
Ben Harshbarger
Attorney-in-fact
​​​​​​May 11, 2023​
 
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