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 we are not soliciting offers to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to completion, dated October 5, 2020PRELIMINARY PROSPECTUS SUBJECT TO COMPLETION, DATED JANUARY 20, 2023

$200,000,000

PROSPECTUS

PROSPECTUS

SUMMIT THERAPEUTICS INC.

Debt Securities

Common Stock

Preferred Stock

Units

Warrants

WeSummit Therapeutics Inc. is distributing at no charge to the holders of our common stock, par value $0.01 per share, non-transferable subscription rights (each, a “Subscription Right”) to purchase up to 476,190,476 shares of common stock (the “Rights Offering”) at the Initial Price (as defined below) with an aggregate offering value of up to $500,000,000. The subscription price per share of common stock shall be equal to the lesser of (i) $1.05 (the “Initial Price”) and (ii) the volume weighted-average price of our common stock for the preceding five-day trading period through and including the Expiration Date (as defined below) (the “Alternate Price”), as provided herein. Each stockholder will receive one Subscription Right entitling the holder to purchase 2.152353 shares of common stock at the Initial Price (the “Basic Subscription Right”), for each share of our common stock owned at 4:00 p.m., Eastern Time, on [●] (the “Record Date”). To the extent that the Alternate Price is lower than the Initial Price, we will sell additional shares of common stock in the Rights Offering, provided that we will not issue any fractional shares of common stock. For a more detailed discussion, see “Rights Offering —Subscription Rights — Basic Subscription Rights” beginning on page 40. The Initial Price or Alternate Price, as applicable, is sometimes referred to herein as the “Subscription Price”. The Subscription Price may offerpresent a significant discount to the recent closing trading price of $4.23 on January 19, 2023. Following the closing of the Rights Offering, there is no assurance that the price will remain at the current trading price, and sell securities from timethe price may decline to timethe Subscription Price, or to a price lower than the Subscription Price. For a more detailed discussion, see “Dilution” beginning on page 37. If the Rights Offering is not fully subscribed and you fully exercise your Basic Subscription Right, you may also exercise your Subscription Rights to purchase additional shares of common stock at the Subscription Price that were not subscribed for by other Subscription Rights holders under the Rights Offering (the “Over-Subscription Right”), subject to the availability and pro rata allocation of shares among persons exercising this Over-Subscription Right. However, we will not issue shares in excess of the total amount authorized by our Board of Directors. For a more detailed discussion, see “Rights Offering” beginning on page 40.

The purpose of this Rights Offering is to raise equity capital in a cost-effective manner that provides all of our existing stockholders the opportunity to participate. The net proceeds will be used for one or more offerings of the following purposes: (i) the repayment to Robert W. Duggan, the Company’s Chief Executive Officer, Chairman of the Board, and beneficial owner of approximately 78.1% of the Company’s common stock and Dr. Mahkam Zanganeh, the Company’s co-Chief Executive Officer, President, member of the Board and beneficial owner of approximately 6.0% of the Company’s common stock, of certain unsecured promissory notes totaling $420 million issued pursuant to the Note Purchase Agreement and (ii) general corporate purposes, which includes funding the Company’s activities to support clinical development and regulatory approval for ivonescimab (also referred to herein as SMT112) and pursue business development opportunities to expand or enhance our pipeline of drug candidates. For a more detailed discussion, see “Use of Proceeds” beginning on page 35.

On December 5, 2022, we entered into a Collaboration and License Agreement (the “License Agreement”) with Akeso, Inc. and its affiliates (“Akeso”) and certain ancillary transaction documents as set forth in the License Agreement. The License Agreement was subject to customary closing conditions, including applicable waiting periods under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (the “HSR Act”). Pursuant to the terms of the License Agreement, we are obligated to make an upfront payment of $500 million, $300 million of which is payable within the later of 15 days after execution of the License Agreement or upon the earliest date on which the parties have actual knowledge that all applicable waiting periods under the HSR Act and any comparable extension periods with respect to the transactions contemplated by the License Agreement have expired or been terminated (the “Antitrust Clearance Date”) and $200 million of which is payable upon the later of (i) 90 days after the execution of the License Agreement or (ii) the Antitrust Clearance Date. In connection with the first payment, Akeso may elect to receive up to $200,000,00016 million shares of Company common stock in lieu of cash. Following the Antitrust Clearance Date, on January 17, 2023 the License Agreement closed and Akeso was issued 10 million shares of Company common stock and was paid $274.9 million dollars in cash. The $200 million remaining amount of the $500 million upfront payment is payable March 5, 2023. For a more detailed discussion, see “Prospectus Summary” beginning on page 18.

On December 6, 2022, we entered into a Note Purchase Agreement (the “Note Purchase Agreement”) and promissory notes with Robert W. Duggan, the Company’s Chief Executive Officer, Chairman of the Board, and beneficial owner of approximately 78.1% of the Company’s common stock and Dr. Mahkam Zanganeh, the Company’s co-Chief Executive Officer, President, member of the Board and beneficial owner of approximately 6.0% of the Company’s common stock. Pursuant to the Note Purchase Agreement, the Company agreed to sell to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate offering price. This prospectus describesamount of $520 million for the general termsprincipal purpose of these securities andfunding the general manner in which these securitiesCompany’s initial payment obligations under the License Agreement. These unsecured promissory notes will be offered. Werepaid, in part, with the proceeds of this Rights Offering. For a more detailed discussion, see “Prospectus Summary — Other Material Agreements” beginning on page 21.

The Subscription Rights will providebe distributed and exercisable beginning on the specific termsdate of these securities in supplements to this prospectus. The prospectus supplementsSubscription Rights will expire and will have no value if they are not exercised prior to the expiration date of this Rights Offering, which is currently expected to be 5:00 p.m. Eastern Time, on [●] (the “Expiration Date”), unless we, in our sole discretion, extend the period for exercising the Subscription Rights. We will extend the duration of the Rights Offering as required by applicable law and may choose to extend the Rights Offering if we decide that changes in the market price of our common stock warrant an extension or if we decide that the degree of participation in this Rights Offering by holders of our common stock is less than the level we desire. You should carefully consider whether or not to exercise your Subscription Rights before the Expiration Date. We reserve the right to cancel the Rights Offering at any time before the expiration of the Rights Offering, for any reason.

Robert W. Duggan, our Executive Chairman, Chief Executive Officer, and the beneficial owner of approximately 78.1% of our common stock prior to this Rights Offering, and Dr. Mahkam Zanganeh, our co-Chief Executive Officer, President, a member of our Board of Directors, and the beneficial owner of approximately 6.0% of our common stock prior to this Rights Offering, have each indicated that they intend to participate in the Rights Offering and subscribe for at least the full amount of their Basic Subscription Rights, but have not made any formal binding commitment to participate.

There is no minimum number of shares of common stock that we must sell in order to complete the Rights Offering. If the Rights Offering is not fully subscribed and you fully exercise your Basic Subscription Right, you may also describeexercise your Over-Subscription Right, subject to the specific manneravailability and pro rata allocation of shares among persons exercising this Over-Subscription Right. Stockholders who do not participate in which thesethe Rights Offering will continue to own the same number of shares, but will own a smaller percentage of the total shares outstanding after the Rights Offering to the extent that other stockholders participate in the Rights Offering. Rights that are not exercised by the Expiration Date will expire and have no value.

We are distributing the rights and offering the underlying securities directly to you. We have not employed any brokers, dealers or underwriters in connection with the solicitation or exercise of rights in the Rights Offering and no commissions, fees or discounts will be offeredpaid in connection with the Rights Offering. Broadridge Corporate Issuer Solutions, LLC is acting as the subscription agent and information agent for the Rights Offering. While certain of our directors, officers and other employees may also supplement, updatesolicit responses from you, those directors, officers and other employees will not receive any commissions or amend information containedcompensation for their services other than their normal compensation.

If you want to participate in this document. YouRights Offering and you are the record holder of your shares, we recommend that you submit your subscription documents to the Subscription Agent well before the deadline. If you want to participate in this Rights Offering and you hold shares through your broker, dealer, bank, or other nominee, you should read this prospectuspromptly contact your broker, dealer, bank, or other nominee and any applicable prospectus supplement carefully before you invest.

We may offer these securitiessubmit your subscription documents in amounts, at pricesaccordance with the instructions and on terms determined atwithin the time of offering. period provided by your broker, dealer, bank, or other nominee.

The securitiesSubscription Rights may not be sold directlyor transferred except as required by operation of law and will not be listed for trading on NASDAQ or any other stock exchange or market. You are urged to you, through agents, or through underwriters and dealers. If agents, underwriters or dealers are used to sell the securities, we will name them and describe their compensation inobtain a prospectus supplement.current price quote for our common stock before exercising your Subscription Rights.

Our common stock is listed on the Nasdaq Global Market under the symbol “SMMT.”“SMMT”. On January 19, 2023, the last reported sales price of our common stock was $4.23.

Investing in theseour securities involves significant risks.a high degree of risk. See “Risk Factors” included“Risk Factors” beginning on page 23 of this prospectus and page 41 of our Annual Report on Form 10-K for the year ended December 31, 2021, incorporated by reference herein as well as the other information contained in any accompanyingthis prospectus supplement and in the documents incorporated by reference in this prospectus or in any accompanying prospectus supplement for a discussion of the factors you should carefully consider before decidingmaking a decision to purchase theseinvest in our securities.

The Board is making no recommendations regarding your exercise of the Subscription Rights. You should carefully consider whether to exercise your Subscription Rights before the Expiration Date. You may not revoke or revise any exercises of Subscription Rights once made, unless we terminate the Rights Offering.

You should rely only on the information contained in this prospectus or any prospectus supplement or amendment hereto. We have not authorized anyone to provide you with different information.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacydetermined if this prospectus is truthful or accuracy of this prospectus.complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2020.[●]

TABLE OF CONTENTSPage

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 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 http://www.summitplc.com. Our website is not a part of this prospectus and is notdocuments incorporated by reference herein, including in our Annual Report on Form 10-K for the fiscal year ended December 31, 2021 and other documents incorporated by reference into this prospectus, constitute forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “potential” “intends” or “continue,” or the negative of these terms or other comparable terminology.

These forward-looking statements may include, but are not limited to, statements relating to our objectives, plans and strategies, statements that contain projections of results of operations or of financial condition, expected capital needs and expenses, statements relating to the research, development, completion and use of our products, and all statements (other than statements of historical facts) that address activities, events or developments that we intend, expect, project, believe or anticipate will or may occur in the future.

Forward-looking statements are not guarantees of future performance and are subject to risks and uncertainties. We have based these forward-looking statements on assumptions and assessments made by our management in light of their experience and their perception of historical trends, current conditions, expected future developments and other factors they believe to be appropriate.

Important factors that could cause actual results, developments and business decisions to differ materially from those anticipated in these forward-looking statements include, among others, those factors referred to in our Annual Report on Form 10-K for the fiscal year ended December 31, 2021, and Quarterly Reports on Form 10-Q filed thereafter, which are incorporated by reference herein.

These statements are only current predictions and are subject to known and unknown risks, uncertainties, and other factors that may cause our or our industry’s actual results, levels of activity, performance or achievements to be materially different from those anticipated by the forward-looking statements. We discuss many of these risks in this prospectus.

This prospectus is part of a registration statement we filed within greater detail under the SEC. This prospectus omits some informationheading “Risk Factors” and other risk factors contained in the registration statement in accordance with SEC rules and regulations.documents incorporated by reference herein. You should reviewnot rely upon forward-looking statements as predictions of future events.

Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance, or achievements. Except as required by law, we are under no duty to update or revise any of the forward-looking statements, whether as a result of new information, future events or otherwise, after the date of this prospectus.

SUMMARY OF THE RIGHTS OFFERING

QUESTIONS AND ANSWERS RELATING TO THE RIGHTS OFFERING

The following are examples of what we anticipate will be common questions about the Rights Offering. The answers are based on selected information included elsewhere in this prospectus. The following questions and answers do not contain all of the information that may be important to you and exhibits inmay not address all of the registration statement for furtherquestions that you may have about the Rights Offering. This prospectus and the documents incorporated by reference into this prospectus contain more detailed descriptions of the terms and conditions of the Rights Offering and provide additional information about us and our consolidated subsidiariesbusiness, including potential risks related to the Rights Offering, the shares offered hereby, and our business. We urge you to read this entire prospectus and the documents incorporated by reference into this prospectus.

In order to properly exercise your Over-Subscription Right, you must deliver the subscription payment for exercise of your Over-Subscription Right before the expiration of the Rights Offering. Because we are offering. Statementswill not know the total number of unsubscribed shares of common stock before the expiration of the Rights Offering, if you wish to maximize the number of shares you purchase pursuant to your Over-Subscription Right, you will need to deliver payment in this prospectus concerning any document we filed as an exhibitamount equal to the registration statement oraggregate Subscription Price for the maximum number of shares of common stock available, assuming that we otherwise filed withno stockholder other than you has purchased any shares of common stock pursuant to such stockholder’s Basic Subscription Right and Over-Subscription Right. Any excess subscription payments received by the SEC are not intended tosubscription agent caused by proration will be comprehensive and are qualifiedreturned by reference to these filings. You should review the complete document to evaluate these statements. You can obtain a copy of the registration statement from the SEC’s website.

INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference in this prospectus much of the information we file with the SEC, which means that we can disclose important informationsubscription agent 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 withmail, without interest or penalty, as soon as practicable after the SEC, this prospectus is continually updated and those future filings may modify or supersede someExpiration Date of the information included or incorporatedRights Offering. The subscription agent will return any excess payments in this prospectus. This means that you must look at allthe form in which it was made. Any Excess Subscription Amount resulting from the reduction of the SEC filingsSubscription Price from the Initial Price to the Alternate Price will be allocated towards the purchase of additional shares of common stock (either towards your Basic Subscription Right, if available, or towards the Over-Subscription Right if you have already exercised your Basic Subscription Right in full). See “The Rights Offering — Subscription Rights — Over-Subscription Rights” beginning on page 40.

If you send a payment that we incorporate by referenceis insufficient to determinepurchase the number of shares of common stock you requested, or if anythe number of shares of common stock you requested is not specified in the forms, the payment received will be applied to exercise your Subscription Rights to the fullest extent possible based on the amount of the statementspayment received, subject to the availability of shares of common stock in this prospectus or in any document previously incorporatedthe Rights Offering and the elimination of fractional shares. Any excess subscription payments received by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below (File No. 001-36866) and any future filings we make withsubscription agent will be returned promptly, without interest, following the SEC under Sections 13(a), 13(c), 14 or 15(d)expiration of the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to 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:Rights Offering.

Please note that we will not accept payment by means of uncertified personal check, bank draft or cashier’s check.

Robert W. Duggan, our Executive Chairman, Chief Executive Officer, and the beneficial owner of approximately 78.1% of our outstanding common stock prior to this Rights Offering, and Dr. Mahkam Zanganeh, our co-Chief Executive Officer, President, a member of our Board of Directors, and the beneficial owner of approximately 6.0% of our issued and outstanding common stock prior to this Rights Offering, have each indicated that they intend to participate in the Rights Offering and subscribe for at least the full amount of their Basic Subscription Rights, but have not made any formal binding commitment to participate.

The issuance of shares of our common stock in the Rights Offering will dilute, and thereby reduce, your proportionate ownership in our shares of common stock, unless you fully exercise your Basic Subscription Rights. In addition, the issuance of our common stock at a Subscription Price that is less than the market price as of the Record Date for the Rights Offering will likely reduce the price per share of our common stock held by you prior to the Rights Offering.

If your shares are held in your name such that you are the record holder, then you should send your subscription documents, rights certificate and subscription payment, as provided herein, by first class mail or courier service to Broadridge Corporate Issuer Solutions, LLC, the subscription agent. The address for delivery to the subscription agent is as follows:

You may requestYour delivery to a copy of these filings, at no cost, by writing or telephoning us at the followingdifferent address or telephone number:other than by the methods set forth above will not constitute valid delivery. You, or, if applicable, your nominee, are solely responsible for ensuring the subscription agent receives your subscription documents, rights certificate, and subscription payment. You should allow sufficient time for delivery of your subscription materials to the subscription agent and clearance of payment before the expiration of the Rights Offering period.

Summit Therapeutics Inc.

Attention: Investor Relations

Broadridge Corporate Issuer Solutions, LLC
Attn: BCIS Re-Organization Dept.
P.O. Box 1317
Brentwood, NY 11717-0718

(617) 514-7149

FORWARD-LOOKING STATEMENTSPROSPECTUS SUMMARY

This prospectussummary highlights certain information about us, this Rights Offering and selected information contained in the prospectus. This summary is not complete and does not contain all of the information that you should consider before deciding whether to invest in our common stock. For a more complete understanding of the Company and this Rights Offering, we encourage you to read and consider the more detailed information included or incorporated by reference in this prospectus, include “forward-looking statements” within the meaning of Section 27A of the Securities Act, and Section 21E of the Exchange Act. All statements contained or incorporated by reference herein, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans, objectives of management and expected market growth, other than statements of historical facts, are forward-looking statements. The words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “potential,” “will,” “would,” “could,” “should,” “continue,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. You are cautioned that these forward-looking statements are only predictions and are subject to risks, uncertainties and assumptions that are referenced in the section of any accompanying prospectus supplement entitled “Risk Factors.” You should also carefully review the risk factors, see “Risk Factors” beginning on page 23, and cautionary statements described in the other documents we file from time to time with the SEC, specifically our most recent Annual Reportconsolidated financial statements and related notes. As described below, on Form 10-K, our Quarterly ReportsDecember 5, 2022, we entered into the License Agreement (as defined below), pursuant to which we will partner with Akeso (as defined below) to in-license its breakthrough bispecific antibody, ivonescimab, known as AK112 in China and Australia, and also as SMT112 in the United States, Canada, Europe, and Japan. The License Agreement and transactions contemplated thereby closed on Form 10-QJanuary 17, 2023. and our Current Reports on Form 8-K. We undertake no obligation to revise or update any forward-looking statements, except to the extent required by law.

THE COMPANYOverview

We are a biopharmaceutical company focused on the discovery, development, and commercialization of novel antibioticspatient-, physician-, caregiver- and societal-friendly medicinal therapies intended to improve quality of life, increase potential duration of life, and resolve serious unmet medical needs. Our pipeline of product candidates is designed with the goal to become the patient-friendly, new-era standard-of-care medicines.

On September 28, 2022, we determined that we would seek partners or a divestiture of ridinilazole, our lead product candidate for serious infectious diseases.treating patients suffering from Clostridioides difficile infection, also known as C. difficile infection, or CDI, as the path forward for the clinical development of the asset. As a result of this determination, we discontinued our only active study for ridinilazole, a pediatric clinical trial evaluating ridinilazole for treating adolescent patients with CDI. We are conductingcurrently involved in activities related to closeout of ridinilazole clinical trials.

Our second product candidate, SMT-738, is being developed for combating multidrug resistant infections, specifically carbapenem-resistant Enterobacteriaceae (“CRE”) infections. SMT-738 is the first of a Phase 3novel class of precision antibiotics that has entered into preclinical development. SMT-738 is currently undergoing IND-enabling activities. We have been and will continue to pursue partnership discussions to continue the development of SMT-738.

We have two additional discovery-phase targets in our pipeline with undisclosed targets in the therapeutic area of oncology.

On December 5, 2022, we entered into a Collaboration and License Agreement (the “License Agreement”) with Akeso, Inc. and its affiliates (“Akeso”) pursuant to which we are partnering with Akeso to in-license its breakthrough bispecific antibody, ivonescimab. Ivonescimab, known as AK112 in China and Australia, and also as SMT112 in the United States, Canada, Europe, and Japan, is a novel, potential first-in-class bispecific antibody intending to combine the power of immunotherapy via a blockade of PD-1 with the anti-angiogenesis benefits of an anti-VEGF into a single molecule. Ivonescimab was engineered to bring two well established oncology targeted mechanisms together. Through the License Agreement, we obtained the rights to develop and commercialize SMT112 in the United States, Canada, Europe, and Japan. The License Agreement and transactions contemplated thereby closed on January 17, 2023.

The entry into the License Agreement and potential partnership or divestiture of ridinilazole represents a material shift in the Company’s strategy. All prior development and marketing activities relating to ridinilazole are being terminated and our future operations will be heavily dependent on the License Agreement and other future activities as the Company determines. The success of this transaction will depend, in part, on the clinical programsuccess of ivonescimab as well as the success of our collaboration with Akeso. This transaction may not result in the realization of the full benefit of any anticipated growth opportunities or these benefits may not be realized within the expected time frames. We will also require significant additional financing to fund the clinical development plan and certain payments contemplated by the License Agreement that could result in an increase in the number of our outstanding shares or the aggregate amount of our debt. If we are unable to raise capital to fund these additional payments, it may cause a material adverse effect on our business.

We have devoted substantially all of our efforts to research and development, including clinical trials. We have not completed the development of any drugs. We expect to continue to incur significant expenses and increasing operating losses for at least the next few years. The net losses we incur may fluctuate significantly from quarter to quarter and year to year, due to the nature and timing of our research and development activities. We expect that our research and development and general and administrative expenses will continue to be significant in connection with our ongoing research and development efforts.

Collaboration and License Agreement

Our License Agreement with Akeso, as referred to above, calls for Summit to receive the rights to develop and commercialize ivonescimab in the United States, Canada, Europe, and Japan (the “Licensed Territory”). Akeso will retain development and commercialization rights for the rest of the regions including China. In exchange for these rights, Summit will make an upfront payment of $500 million, $300 million of which is payable within the later of 15 days after execution of the License Agreement or upon the earliest date on which the parties have actual knowledge that all applicable waiting periods under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 and any comparable extension periods with respect to the transactions contemplated by the License Agreement have expired or been terminated (the “Antitrust Clearance Date”) and $200 million of which is payable within the later of (i) 90 days after execution of the License Agreement or (ii) the Antitrust Clearance Date. In connection with the first payment, up to 16 million shares of Company common stock may be issued in lieu of cash at Akeso’s election (the “Share Transfer”), with the value of such shares based on the ten (10) day volume-weighted average price for the five-trading day period prior to and the five-trading day period after the execution of the License Agreement. The total of the upfront payment and potential milestone payments is $5.0 billion, as Akeso will be eligible to receive regulatory milestones of up to $1.05 billion and commercial milestones of up to $3.45 billion. In addition, Akeso will be eligible to receive low double-digit royalties on net sales. Following the Antitrust Clearance Date, on January 17, 2023, the License Agreement closed and, as initial upfront payment, Akeso was issued 10 million shares of Company common stock pursuant to the Share Transfer and was paid $274.9 million dollars in cash. The $200 million remaining amount of the $500 million upfront payment is payable on March 5, 2023. In connection with the License Agreement, the Company has also agreed to enter into a Supply Agreement with Akeso, pursuant to which Summit agreed to purchase a certain portion of drug substance for clinical and commercial supply (the “Supply Agreement”).

Pursuant to the terms of the License Agreement, Summit will have final decision-making authority with respect to commercial strategy, pricing and reimbursement and other commercialization matters in the Licensed Territory. Summit is not assuming any liabilities (including contingent liabilities), acquiring any physical assets or trade names, or hiring or acquiring any employees from Akeso in connection with the License Agreement. Akeso has incurred research and development expenses relating to ivonescimab, including expenses for pre-clinical studies, as well as safety and efficacy clinical trials in non-licensed territories.

Our Strategy

Our goal is to become a fully integrated biopharmaceutical company focused on the discovery, development, and commercialization of our pipeline product portfolio in the therapeutic area of oncology and/or new era products that work in harmony with the human gut microbiome, including innovative therapeutics for the treatment of certain cancers and infectious diseasediseases.

Product Pipeline

 C. difficileIvonescimab infection. We are also seeking

Ivonescimab is believed to expandbe the PD-1 / VEGF bispecific antibody that is most advanced in the clinic. Ivonescimab has received Breakthrough Therapy Designation status in China from the NMPA for three indications: combination therapy with chemotherapy for NSCLC patients who have failed a previous EGFR-TKI, combination therapy with chemotherapy for NSCLC patients who have failed to respond to a prior PD-(L)1 therapy, and monotherapy as first-line treatment for locally advanced or metastatic NSCLC patients with positive PD-L1 expression. Ivonescimab is currently being developed in China and Australia in multiple solid tumors, including a Phase III clinical trial in patients with NSCLC that is positive for an epidermal growth factor receptor (EGFR) mutation whose disease has progressed after treatment with an EGFR tyrosine-kinase inhibitor (TKI). As presented at ASCO 2022, ivonescimab treatment was associated with an overall response rate (ORR) in a Phase II study in patients with non-small cell lung cancer (NSCLC) who have failed EGFR-TKI’s of 68.4% and a median Progression-Free Survival (mPFS) time period of 8.2 months when combined with combination chemotherapy (pemetrexed and carboplatin) as compared to historical mPFS of 4.3 months in patients treated with combination chemotherapy (pemetrexed and platinum-based chemotherapy) alone, the current standard of care. In a separate cohort, ivonescimab combined with docetaxel in patients who have failed PD-(L)1 and chemotherapies demonstrated a mPFS of 6.6 months as compared to a historical mPFS of 4.5 months with docetaxel alone, a current standard of care regimen for these patients. The study, which similarly had patients receiving ivonescimab plus chemotherapy as their first line therapy for metastatic disease, was considered to have demonstrated a tolerable safety profile and a low discontinuation rate for adverse events. 

Summit has clinical development and commercialization rights for SMT112 in its Licensed Territory (United States, Canada, Europe, and Japan). Summit plans to design and conduct the clinical trial activities for SMT112 in its Licensed Territory, to support and submit relevant regulatory filings. Summit is initiating development activities for ivonescimab and will do so first in NSCLC indications. Summit plans to start treating patients in clinical studies by the second quarter of 2023.

Discuva Platform

In December 2017, we expanded our product candidate portfolio throughactivities in the field of infectious diseases with the acquisition of Discuva Limited, a privately held United Kingdom-based company. Through this acquisition, we obtained a bacterial genetics platform and a suite of software-based technologies (collectively termed our “Discuva Platform”), which facilitate the discovery and development of new mechanism precision antibiotics usingantibiotics. Our Discuva Platform can be used to identify new bacterial targets for drug discovery, understand the mechanism of action of small molecules targeting varying types of bacteria and select the most optimal preclinical candidates, including those with the least propensity to develop bacterial resistance. On January 20, 2023, we announced that given the License Agreement and the Company’s shift in focus to oncology, we will cease further investment in theDiscuva platform and evaluate further options for the use of the Discuva Platform. Based on the evaluation of further options for the use of the Discuva Platform, we willassess the carrying value of the acquired Discuva Platform intangible asset.

Enterobacteriaceae Program

We continue to advance our proprietaryhighly innovative program targeting infections caused by Enterobacteriaceae. We have used our Discuva Platform.Platform to identify our DDS-04 series, a novel chemotype active against a clinically unexploited bacterial target that has the potential to treat Enterobacteriaceae infections. Enterobacteriaceae are a family of bacteria responsible for serious infections across a number of conditions including bloodstream infections, urinary tract infections (“UTI”) and hospital-acquired pneumonias. Multi-drug resistant (“MDR”) Enterobacteriaceae are resistant to treatment by most or occasionally all existing antibiotics. The most difficult to treat among them are the Extended Spectrum Beta-Lactamase (“ESBL”)-producing and the Carbapenem-resistant CRE. According to the Center for Disease Control and Prevention (“CDC”), ESBL-producing and CRE Enterobacteriaceae have collectively caused an estimated 197,400 infections and 9,100 deaths in hospitalized patients in the United States in 2019. Our DDS-04 series continues to build on highly promising preclinical in vivo efficacy data with an immediate focus on a new antibiotic agent for the treatment of complicated urinary tract infections, pneumonia and the associated bacteremia.

Our lead preclinical candidate for the Enterobacteriaceae program from the DDS-04 series is SMT026738 (formerly “DIS-0104145” and referred to as “SMT-738”). SMT-738 is a novel small molecule inhibitor of the essential bacterial lipoprotein transport system (LolCDE) in Gram-negative bacteria, which displays a narrow spectrum of activity towards Enterobacteriaceae. SMT-738 has demonstrated potent in vitro activity against global MDR isolates of E. coli and K. pneumoniae, including the clinically challenging NDM-carrying CRE isolates where many currently available treatment options have succumbed to clinical resistance including colistin, an antibiotic of last resort. Most importantly, SMT-738 has also shown robust in vivo efficacy in relevant murine models of UTI, pneumonia and sepsis. A preliminary rodent toxicity study has been concluded and the data supports the continued clinical development of SMT-738. SMT-738 has the potential to become a first in class antibiotic to treat life-threatening infections. We retain worldwide clinical development and commercial rights to SMT-738 and plan to continue to perform IND-enabling activities. We have been and will continue to pursue partnership discussions to continue the development of SMT-738.

Other Material Agreements

On December 6, 2022, we entered into a Note Purchase Agreement (the “Note Purchase Agreement”) and promissory notes with Robert W. Duggan, the Company’s Chief Executive Officer, Chairman of the Board, and beneficial owner of approximately 78.1% of the Company’s common stock and Dr. Mahkam Zanganeh, the Company’s co-Chief Executive Officer, President, member of the Board and beneficial owner of approximately 6.0% of the Company’s common stock. Pursuant to the Note Purchase Agreement, the Company agreed to sell to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate amount of $520 million.

Pursuant to the Note Purchase Agreement, the Company has issued to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the amount of $400 million and $20 million, respectively (the “February Notes”), which will mature and become due on February 15, 2023 (the “February Maturity Date”) and an unsecured promissory note to Mr. Duggan in the amount of $100 million (the “September Note” and together with the February Notes, the “Notes”), which will mature and become due on September 15, 2023 (the “September Maturity Date” and together with the February Maturity Date, the “Maturity Dates”). The Maturity Dates may be extended one or more times at the Company’s election, but in no event to a date later than September 6, 2024. The Notes accrue interest at an initial rate of 7.5%. All interest on the Notes shall be paid on the date of signing for the period through the February Maturity Date. Such prepaid interest shall be paid in a number of shares of the Company’s common stock, par value $0.01 equal to the dollar amount of such prepaid interest, divided by $0.7913 (the consolidated closing bid price immediately preceding the time the Company entered into the Note Purchase Agreement, plus $0.01), which is 9,720,291 shares. If the Company exercises its right to extend the term of the February Notes for all periods following the February Maturity Date and, with respect to the September Note following the February Maturity Date, interest shall accrue on the outstanding balance of such extended Notes at the US prime interest rate plus 50 basis points, as adjusted monthly, for three months immediately following the Maturity Date, and thereafter at the US prime rate plus 300 basis points, as adjusted monthly, in each case payable in cash quarterly in arrears. In addition, if the Company shall consummate a public offering, then upon the later to occur of (i) five business days after the Company receives the net cash proceeds therefrom or (ii) May 15, 2023, the February Notes shall be prepaid by an amount equal to the lesser of (a) 100% of the amount of the net proceeds of such offering and (b) the outstanding principal amount on such Notes. In January 2023, the Company provided notice to Mr. Duggan that it has elected to extend the Maturity Dates of the $400 million February Note and the September Note to September 6, 2024. The Company and Mr. Duggan have rectified the $400 million February Note and the September Note in order to correctly reflect the parties’ intent in such notes that the Company may only prepay (i) the $400 Million February Note following the completion of the Rights Offering, or a similar capital raise, in an amount equal to the lesser of (x) the net proceeds of the Rights Offering or such capital raise or (y) the full amount outstanding of the such note, and (ii) the September Note following the completion of a capital raising transaction subsequent to the Rights Offering in an amount equal to the lesser of (i) the net proceeds of such capital raise or (ii) the full amount outstanding of the September Note.

The Company intends to repay the February Notes within five business days following the consummation of this Rights Offering in an amount equal to the lesser of (a) 100% of the amount of the net proceeds of the Rights Offering and (b) the outstanding principal amount on such Notes. The Notes were issued to Mr. Duggan and Dr. Zanganeh, as applicable, in a private placement in reliance on Regulation D promulgated under the Securities Act of 1933, as amended. The Notes have not been registered under the Securities and Exchange Act of 1933, as amended, and may not be offered or sold absent registration or an applicable exemption from registration requirements.

Liquidity

As of the date of this filing, the Company has received $520 million from the Note Purchase Agreement as discussed above. On January 17, 2023, Akeso was issued 10 million shares of Company common stock pursuant to the Share Transfer and was paid $274.9 million dollars in cash. The Company expects to use the proceeds of the Note Purchase Agreement to support (i) payment of the upfront obligation totaling $500 million associated with the License Agreement as described above (which includes the payment of $274.9 million in cash referenced in the preceding sentence); (ii) activities to support clinical development and regulatory approval for SMT112; (iii) its pursuit of business development opportunities to expand or enhance our pipeline of drug candidates; and (iv) general corporate purposes. In January 2023, the Company provided notice to Mr. Duggan that it has elected to extend the Maturity Dates of the $400 million February Note and the September Note to September 6, 2024.

The purpose of this Rights Offering is to raise equity capital in a cost-effective manner that provides all of our existing stockholders the opportunity to participate. The net proceeds will be used for one or more of the following purposes: (i) the repayment of certain unsecured promissory notes totaling $420 million issued pursuant to the Note Purchase Agreement and (ii) general corporate purposes, which includes funding the Company’s activities to support clinical development and regulatory approval for SMT112 and pursue business development opportunities to expand or enhance our pipeline of drug candidates.

We believe that our existing cash, cash equivalents and U.K. research and development tax credits, together with the net proceeds from this Rights Offering after the repayment of certain unsecured promissory notes totaling $420 million issued pursuant to the Note Purchase Agreement, will be sufficient to fund our operations and initially planned clinical trials for ivonescimab into the second half of 2024. If the Company is unable to successfully complete this Rights Offering, or if the net proceeds are significantly less than expected, the Company would seek other funding alternatives. However, if additional funding is not available, or is not available on terms acceptable to the Company, the Company will focus its available capital on certain initially planned clinical trials for ivonescimab. This would allow the Company to be able to operate into the third quarter of 2024. These actions could adversely affect the Company’s business prospects.

The Company expects to continue generating operating losses for the foreseeable future. Until the Company can generate substantial revenue and achieve profitability, the Company will need to raise additional capital to fund its ongoing operations and capital needs. The Company continues to evaluate options to further finance its operating cash needs for its product candidates through a combination of some, or all, of the following: equity and debt offerings, collaborations, strategic alliances, grants and clinical trial support from government entities, philanthropic, non-government and not-for-profit organizations and patient advocacy groups, and marketing, distribution or licensing arrangements. While the Company believes that funds would be available in this manner before 2024, there is no assurance, however, that additional financing will be available when needed or that management of the Company will be able to obtain financing on terms acceptable to the Company. If the Company is unable to obtain funding when required in the future, the Company could be required to delay, reduce, or eliminate research and development programs, product portfolio expansion, or future commercialization efforts, which could adversely affect its business prospects.

Corporate Information

Summit Therapeutics Inc. was incorporated in Delaware on July 17, 2020. Our principal executive offices areoffice is located at One Broadway, 14th Floor, Cambridge, Massachusetts 02142,2882 Sand Hill Road, Suite 106, Menlo Park, California and our telephonephone number is (617) 514-7149. Our website is https://www.smmttx.com. Information contained on or accessible through our website is not incorporated by reference into this prospectus and should not be considered a part of this prospectus.

514-7149.Recent Developments

DESCRIPTION OF DEBT SECURITIES

While we have no current agreements, commitments or understandings for any specific acquisitions at this time other than the License Agreement, we may use a portion of the net proceeds for these purposes. We may offer debt securities which may be senior or subordinated. We referbelieve that our existing cash, cash equivalents and U.K. research and development tax credits, together with the net proceeds from this Rights Offering, will fund our operations and initially planned clinical trials for ivonescimab into the second half of 2024.

As previously disclosed, on December 6, 2022, we entered into the Note Purchase Agreement and promissory notes with Robert W. Duggan, the Company’s Chief Executive Officer, Chairman of the Board, and beneficial owner of approximately 78.1% of the Company’s common stock and Dr. Mahkam Zanganeh, the Company’s co-Chief Executive Officer, President, member of the Board and beneficial owner of approximately 6.0% of the Company’s common stock. Pursuant to the senior debt securitiesNote Purchase Agreement, the Company agreed to sell to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate amount of $520 million for the principal purpose of funding the Company’s initial payment obligations under the License Agreement. The Company expects to use the proceeds of the Note Purchase Agreement to support (i) payment of the upfront obligation totaling $500 million associated with the License Agreement as described herein; (ii) activities to support clinical development and regulatory approval for SMT112; (iii) pursue business development opportunities to expand or enhance our pipeline of drug candidates; and (iv) general corporate purposes.

This expected use of the net proceeds from this Rights Offering represents our intentions based upon our current plans and business conditions and numerous factors, including the factors described under “Risk Factors.” As of the date of this prospectus, we cannot predict with certainty all of the particular uses for the net proceeds to be received upon the completion of this Rights Offering or the amounts that we will actually spend on the uses set forth above. The amounts and timing of our actual expenditures and the subordinated debt securities collectivelyuse of these proceeds may vary significantly depending on numerous factors, including the progress of our expansion efforts and acquisition activities, as debt securities. well as any unforeseen cash needs. As a result, our management will retain broad discretion over the allocation of the net proceeds from this Rights Offering.

CAPITALIZATION

The following description summarizestable sets forth our capitalization as of September 30, 2022 to reflect the general terms and provisionsfollowing:

The following table does not consider the second upfront payment due to Akeso of $200 million pursuant to the License Agreement, as this is expected to be paid after the consummation of the debt securities. We will describeRights Offering.

The information presented in the specific termstable below should be read in conjunction with “Management’s Discussion and Analysis of the debt securitiesFinancial Condition and Results of Operations” and the extent, if any,historical consolidated financial statements and notes thereto included in our Form 10-Q for the quarter ended September 30, 2022, which is incorporated into this prospectus by reference.

When we refer to “principal” in this section with reference to the debt securities, we are also referring to “premium, if any.”

We may from time to time, without notice to or the consent of the holders of any series of debt securities, create and issue further debt securities of any such series ranking equally with the debt securities of such series in all respects (or in all respects other than (1) the payment of interest accruing prior to the issue date of such further debt securities or (2) the first payment of interest following the issue date of such further debt securities). Such further debt securities may be consolidated and form a single series with the debt securities of such series and have the same terms as to status, redemption or otherwise as the debt securities of such series.

You may present debt securities for exchange and you may present debt securities for transfer in the manner, at the places and subject to the restrictions set forth in the debt securities and the applicable prospectus supplement. We will provide you those services without charge, although you may have to pay any tax or other governmental charge payable in connection with any exchange or transfer, as set forth in the indenture.

Debt securities may bear interest at a fixed rate or a floating rate. Debt securities bearing no interest or interest at a rate that at the time of issuance is below the prevailing market rate (original issue discount securities) may be sold at a discount below their stated principal amount. U.S. federal income tax considerations applicable to any such discounted debt securities or to certain debt securities issued at par which are treated as having been issued at a discount for U.S. federal income tax purposes will be described in the applicable prospectus supplement.

We may issue debt securities with the principal amount payable on any principal payment date, or the amount of interest payable on any interest payment date, to be determined by reference to one or more currency exchange rates, securities or baskets of securities, commodity prices or indices. You may receive a payment of principal on any principal payment date, or a payment of interest on any interest payment date, that is greater than or less than the amount of principal or interest otherwise payable on such dates, depending on the value on such dates of the applicable currency, security or basket of securities, commodity or index. Information as to the methods for determining the amount of principal or interest payable on any date, the currencies, securities or baskets of securities, commodities or indices to which the amount payable on such date is linked and certain related tax considerations will be set forth in the applicable prospectus supplement.

Certain Terms of the Senior Debt Securities

Covenants. Unless we indicate otherwise in a prospectus supplement with respect to a particular series of senior debt securities, the senior debt securities will not contain any financial or restrictive covenants, including covenants restricting either us or any of our subsidiaries from incurring, issuing, assuming or guaranteeing any indebtedness secured by a lien on any of our or our subsidiaries’ property or capital stock, or restricting either us or any of our subsidiaries from entering into sale and leaseback transactions.

Consolidation, Merger and Sale of Assets. Unless we indicate otherwise in a prospectus supplement with respect to a particular series of senior debt securities, we may not consolidate with or merge into any other person, in a transaction in which we are not the surviving corporation, or convey, transfer or lease our properties and assets substantially as an entirety to any person, in either case, unless:

The following table illustrates this per-share dilution, assuming the Rights Offering is fully subscribed at the assumed Subscription Price of $1.05 per share of common stock. To the extent that the Alternate Price is lower than the Initial Price, purchasers of our common stock in the Rights Offering will experience further dilution.

Events of Default. Unless we indicate otherwise in a prospectus supplement with respect to a particular series of senior debt securities, the following are events of default under the senior indenture with respect to senior debt securities of each series:

The default by us under any other debt, including any other series of debt securities, is not a default under the senior indenture.

If an event of default other than an event of default specified in the fourth bullet point above occurs with respect to a series of senior debt securities and is continuing under the senior indenture, then, and in each such case, either the trustee or the holders of not less than 25% in aggregate principal amount of such series then outstanding under the senior indenture (each such series voting as a separate class) by written notice to us and to the trustee, if such notice is given by the holders, may, and the trustee at the request of such holders shall, declare the principal amount of and accrued interest on such series of senior debt securities to be immediately due and payable, and upon this declaration, the same shall become immediately due and payable.

If an event of default specified in the fourth bullet point above occurs and is continuing, the entire principal amount of and accrued interest on each series of senior debt securities then outstanding shall automatically become immediately due and payable.

Unless otherwise specified in the prospectus supplement relating to a series of senior debt securities originally issued at a discount, the amount due upon acceleration shall include only the original issue price of the senior debt securities, the amount of original issue discount accrued to the date of acceleration and accrued interest, if any.

Upon certain conditions, declarations of acceleration may be rescinded and annulled and past defaults may be waived by the holders of a majority in aggregate principal amount of all the senior debt securities of such series affected by the default, each series voting as a separate class. Furthermore, subject to various provisions in the senior indenture, the holders of a majority in aggregate principal amount of a series of senior debt securities, by notice to the trustee, may waive a continuing default or event of default with respect to such senior debt securities and its consequences, except a default in the payment of principal of or interest on such senior debt securities (other than any such default in payment resulting solely from an acceleration of the senior debt securities) or in respect of a covenant or provision of the senior indenture which cannot be modified or amended without the consent of the holders of each such senior debt security. Upon any such waiver, such default shall cease to exist, and any event of default with respect to such senior debt securities shall be deemed to have been cured, for every purpose of the senior indenture; but no such waiver shall extend to any subsequent or other default or event of default or impair any right consequent thereto.

The holders of a majority in aggregate principal amount of a series of senior debt securities may direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to such senior debt securities. However, the trustee may refuse to follow any direction that conflicts with law or the senior indenture, that may involve the trustee in personal liability or that the trustee determines in good faith may be unduly prejudicial to the rights of holders of such series of senior debt securities not joining in the giving of such direction and may take any other action it deems proper that is not inconsistent with any such direction received from holders of such series of senior debt securities. A holder may not pursue any remedy with respect to the senior indenture or any series of senior debt securities unless:

These limitations, however, do not apply to the right of any holder of a senior debt security of any affected series to receive payment of the principal of and interest on such senior debt security in accordance with the terms of such debt security, or to bring suit for the enforcement of any such payment in accordance with the terms of such debt security, on or after the due date for the senior debt securities, which right shall not be impaired or affected without the consent of the holder.

The senior indenture requires certain of our officers to certify, on or before a fixed date in each year in which any senior debt security is outstanding, as to their knowledge of our compliance with all covenants, agreements and conditions under the senior indenture.

Satisfaction and Discharge. We can satisfy and discharge our obligations to holders of any series of debt securities if:

and if, in any such case, we also pay or cause to be paid all other sums payable under the senior indenture, as and when the same shall be due and payable and we deliver to the senior trustee an officer’s certificate and an opinion of counsel, each stating that these conditions have been satisfied.

Under current U.S. federal income tax law, the deposit and our legal release from the debt securities would be treated as though we took back your debt securities and gave you your share of the cash and debt securities or

bonds deposited in trust. In that event, you could recognize gain or loss on the debt securities you give back to us. Purchasers of the debt securities should consult their own advisers with respect to the tax consequences to them of such deposit and discharge, including the applicability and effect of tax laws other than the U.S. federal income tax law.

Defeasance. Unless the applicable prospectus supplement provides otherwise, the following discussion of legal defeasance and covenant defeasance will apply to any series of debt securities issued under the indentures.

Legal Defeasance. We can legally release ourselves from any payment or other obligations on the debt securities of any series (called “legal defeasance”) if certain conditions are met, including the following:

If we accomplish legal defeasance, as described above, you would have to rely solely on the trust deposit for repayment of the debt securities. You could not look to us for repayment in the event of any shortfall.

Covenant Defeasance. Without any change in current U.S. federal tax law, we can make the same type of deposit described above and be released from some of the covenants in the debt securities (called “covenant defeasance”). In that event, you would lose the protection of those covenants but would gain the protection of having money and securities set aside in trust to repay the debt securities. In order to achieve covenant defeasance, we must do the following (among other things):

If we accomplish covenant defeasance, you could still look to us for repayment of the debt securities if there were a shortfall in the trust deposit. In fact, if one of the events of default occurred (such as our bankruptcy) and the debt securities become immediately due and payable, there may be such a shortfall. Depending on the events causing the default, you may not be able to obtain payment of the shortfall.

Modification and Waiver. We and the trustee may amend or supplement the senior indenture or the senior debt securities of any series without the consent of any holder:

Other amendments and modifications of the senior indenture or the senior debt securities issued may be made, and our compliance with any provision of the senior indenture with respect to any series of senior debt securities may be waived, with the consent of the holders of a majority of the aggregate principal amount of the outstanding senior debt securities of each series affected by the amendment or modification (voting as a separate series); provided, however, that each affected holder must consent to any modification, amendment or waiver that:

It shall2020 Stock Incentive Plan and 2020 Employee Stock Purchase Plan, which have not be necessary for the holders to approve the particular form of any proposed amendment, supplement or waiver, but it shall be sufficient if the holders’ consent approves the substance thereof. After an amendment, supplement or waiver of the senior indenture in accordance with the provisions described in this section becomes effective, the trustee must give to the holders affected thereby certain notice briefly describing the amendment, supplement or waiver. Any failureyet been determined by the trustee to give such notice, or any defect therein, shall not, however, in any way impair or affect the validity of any such amendment, supplemental indenture or waiver.

No Personal Liability of Incorporators, Stockholders, Officers, Directors. The senior indenture provides that no recourse shall be had under any obligation, covenant or agreement of ours in the senior indenture or any supplemental indenture, or in any of the senior debt securities or because of the creation of any indebtedness represented thereby, against any of our incorporators, stockholders, officers or directors, past, present or future, or of any predecessor or successor entity thereof under any law, statute or constitutional provision or by the enforcement of any assessment or by any legal or equitable proceeding or otherwise. Each holder, by accepting the senior debt securities, waives and releases all such liability.

Concerning the Trustee. The senior indenture provides that, except during the continuance of an event of default, the trustee will not be liable except for the performance of such duties as are specifically set forth in the senior indenture. If an event of default has occurred and is continuing, the trustee will exercise such rights and powers vested in it under the senior indenture and will use the same degree of care and skill in its exercise as a prudent person would exercise under the circumstances in the conduct of such person’s own affairs.

The senior indenture and the provisions of the Trust Indenture Act incorporated by reference therein contain limitations on the rights of the trustee thereunder, should it become a creditor of ours or any of our subsidiaries, to obtain payment of claims in certain cases or to realize on certain property received by it in respect of any such claims, as security or otherwise. The trustee is permitted to engage in other transactions, provided that if it acquires any conflicting interest (as defined in the Trust Indenture Act), it must eliminate such conflict or resign.

We may have normal banking relationships with the senior trustee in the ordinary course of business.

Unclaimed Funds. All funds deposited with the trustee or any paying agent for the payment of principal, premium, interest or additional amounts in respect of the senior debt securities that remain unclaimed for

two years after the date upon which such amounts became due and payable will be repaid to us. Thereafter, any right of any holder of senior debt securities to such funds shall be enforceable only against us, and the trustee and paying agents will have no liability therefor.

Governing Law. The senior indenture and the senior debt securities will be governed by, and construed in accordance with, the internal laws of the State of New York.

Certain Terms of the Subordinated Debt Securities

Other than the terms of the subordinated indenture and subordinated debt securities relating to subordination or otherwise as described in the prospectus supplement relating to a particular series of subordinated debt securities, the terms of the subordinated indenture and subordinated debt securities are identical in all material respects to the terms of the senior indenture and senior debt securities.

Additional or different subordination terms may be specified in the prospectus supplement applicable to a particular series.

Subordination. The indebtedness evidenced by the subordinated debt securities is subordinate to the prior payment in full of all of our senior indebtedness, as defined in the subordinated indenture. During the continuance beyond any applicable grace period of any default in the payment of principal, premium, interest or any other payment due on any of our senior indebtedness, we may not make any payment of principal of or interest on the subordinated debt securities (except for certain sinking fund payments). In addition, upon any payment or distribution of our assets upon any dissolution, winding-up, liquidation or reorganization, the payment of the principal of and interest on the subordinated debt securities will be subordinated to the extent provided in the subordinated indenture in right of payment to the prior payment in full of all our senior indebtedness. Because of this subordination, if we dissolve or otherwise liquidate, holders of our subordinated debt securities may receive less, ratably, than holders of our senior indebtedness. The subordination provisions do not prevent the occurrence of an event of default under the subordinated indenture.

The term “senior indebtedness” of a person means with respect to such person the principal of, premium, if any, interest on, and any other payment due pursuant to any of the following, whether outstanding on the date of the subordinated indenture or incurred by that person in the future:Board.

unless, in the case of any particular indebtedness, renewal, extension or refunding, the instrument creating or evidencing it or the assumption or guarantee relating to it expressly provides that such indebtedness, renewal, extension or refunding is not superior in right of payment to the subordinated debt securities. Our senior debt securities constitute senior indebtedness for purposes of the subordinated indenture.

DESCRIPTION OF CAPITAL STOCK

The 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 restated certificate of incorporation, our amended and restated bylaws and applicable provisions of Delaware corporate law. You should read our restated certificate of incorporation and amended and restated bylaws, 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 250,000,0001,000,000,000 shares of common stock, $0.01 par value per share and 20,000,000 shares of preferred stock, $0.01 par value per share. As of September 18, 2020, 67,231,903the Record Date, the Company had 221,241,725 shares of common stock wereissued and outstanding and noan aggregate of 25,481,146 shares reserved for potential future issuance upon exercise of outstanding awards under its 2020 Stock Incentive Plan, 2016 Long Term Incentive Plan, and its outstanding warrants. The Company may also issue up to an additional 8,174,711 authorized shares reserved for potential issuance of future awards under its 2020 Stock Incentive Plan and 2020 Employee Stock Purchase Plan.

On January 6, 2023, the Company held a Special Meeting of Stockholders in which the stockholders approved: (i) an amendment to the Company’s restated certificate of incorporation to increase the number of authorized shares of preferredour common stock were outstanding.by 650,000,000 (from 350,000,000 to 1,000,000,000), and (ii) an amendment to authorize the Board to amend our restated certificate of incorporation to effect a reverse stock split of all of the outstanding shares of our common stock, at a ratio in the range of 1-for-5 to 1-for-10. On January 19, 2023, the Board approved, and the Company filed, an amendment to the amended and restated certificate of incorporation to increase the Company’s capitalization as described in clause (i). The Board reserves the right to adopt the proposal described in clause (ii) at any time prior to January 6, 2024 but has no intention to effect the reverse stock split prior to the closing of the Rights Offering and issuance of shares thereunder.

Common Stock

Annual Meeting. Meeting. Annual meetings of our stockholders are held on the date designated in accordance with our by-laws. Written notice must be mailed to each stockholder entitled to vote not less than ten nor more than 60 days before the date of the meeting. The presence in person or by proxy of the holders of record of a majority of our issued and outstanding shares entitled to vote at such meeting constitutes a quorum for the transaction of business at meetings of the stockholders. Special meetings of the stockholders may be called for any purpose by the board of directors and shall be called by the secretary upon the written request, stating the purpose of such meeting, of the holders of at least twenty-five percent (25%) of the shares of capital stock entitled to vote in an election of directors. Except as may be otherwise provided by applicable law, our certificate of incorporation or our by-laws, all elections shall be decided by a plurality, and all other questions shall 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.

Voting Rights. Each holder of common stock is entitled to one vote for each share held of record on all matters to be voted upon by stockholders.

Dividends. Subject to the rights, powers and preferences of any outstanding preferred stock, and except as provided by law or in our certificate of incorporation, dividends may be declared and paid or set aside for payment on the common stock out of legally available assets or funds when and as declared by the board of directors.

Liquidation, Dissolution and Winding Up. Subject to the rights, powers and preferences of any outstanding preferred stock, in the event of our liquidation, dissolution or winding up, our net assets will be distributed pro rata to the holders of our common stock.

Other Rights. Holders of the common stock have no right to:

The common stock does not have cumulative voting rights. Holders of shares of the common stock are not required to make additional capital contributions.

Transfer Agent and Registrar. Computershare Trust Company, N.A. is transfer agent and registrar for the common stock.

Preferred Stock

We are authorized to issue “blank check” preferred stock, which may be issued in one or more series upon authorization of our board of directors. Our board of directors is authorized to fix the designations, powers, preferences and the relative, participating, optional or other special rights and any qualifications, limitations and restrictions of the shares of each series of preferred stock. The authorized shares of our preferred stock are available for issuance without further action by our stockholders, unless such action is required by applicable law or the rules of any stock exchange on which our securities may be listed. If the approval of our stockholders is not required for the issuance of shares of our preferred 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 prospectus supplement relating to that series of preferred stock.

A series of our preferred 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 for specific terms, including:

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 general creditors.

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:

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 our 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 dividend 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 date 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 declaration 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 distribution 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 the 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 claim 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 will share ratably in any such distribution of assets in proportion to the full 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 preferred stock, we will distribute our remaining assets among the holders of any other classes or series of capital stock ranking junior to the preferred 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 subject to mandatory redemption or redemption at our option, as a whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such prospectus supplement.

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:

In addition, we will not acquire any preferred stock of a series unless:

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 preferred stock of such series as to dividends and upon liquidation.

If fewer than all of the outstanding shares of preferred 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 prospectus supplement, we will mail notice of redemption at least 30 days but not more than 60 days before the redemption date to each holder of record of preferred stock to be redeemed at the address shown on our stock transfer books. Each notice shall state:

If 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 applicable prospectus supplement.

Unless otherwise provided for under the terms of any series of preferred stock, no consent or vote of the holders of shares of preferred stock or any series thereof shall be required for any amendment to our restated 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 convertible into 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.

Transfer Agent and Registrar. The transfer agent and registrar for the preferred stock will be set forth in the applicable prospectus supplement.

Certain Provisions of Our Certificate of Incorporation and By-laws and Delaware Law

Board of DirectorsDirectors. . All of our directors are elected annually. The number of directors comprising our board of directors is fixed from time to time by the board of directors.

Stockholder Nomination of DirectorsDirectors. . Our by-lawsBylaws provide that a stockholder must notify us in writing of any stockholder nomination of a director not earlier than the 120^th day and not later than the 90^th day prior to the first anniversary of the preceding year’s annual meeting; provided, that if the date of the annual meeting is advanced or delayed by more than 30 days from such anniversary date, notice by the stockholder to be timely must be so delivered (x) not earlier than the 120^th day prior to the date of such annual meeting and not later than the 90^th day prior to the date of such meeting and (y) the 10^th day following the day on which public announcement of the date of such annual meeting is first made by us.

Exclusive forum provisionprovision. . Our restated certificateCertificate of incorporationIncorporation provides that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (or, if the Court of Chancery of the State of Delaware does not have jurisdiction, the federal district court for the District of Delaware) shall be the sole and exclusive forum for the following types of proceedings: (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, employees or stockholders to our company or our stockholders, (3) any action asserting a claim arising pursuant to any provision of the General Corporation Law of the State of Delaware or as to which the General Corporation Law of the State of Delaware confers jurisdiction on the Court of Chancery of the State of Delaware, or (4) any action asserting a claim arising pursuant to any provision of our restated certificateCertificate of incorporationIncorporation or amended and restated bylawsBylaws (in each case, as they may be amended from time to time) or governed by the internal affairs doctrine. These choice of forum provisions will not apply to suits brought to enforce a duty or liability created by the Exchange Act. Furthermore, Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts over all such Securities Act actions. Accordingly, both state and federal courts have jurisdiction to entertain such claims. To prevent having to litigate claims in multiple jurisdictions and the threat of inconsistent or contrary rulings by different courts, among other considerations, our certificateCertificate of incorporationIncorporation provides that, unless we consent in writing to the selection of an alternative forum, the federal district courts of the United States of America shall, to the fullest extent permitted by law, be the sole and exclusive forum for the resolution of any claims arising under the Securities Act. While the Delaware courts have determined that such choice of forum provisions are facially valid, a stockholder may nevertheless seek to bring a claim in a venue other than those designated in the exclusive forum provisions. In such instance, we would expect to vigorously assert the validity and enforceability of the exclusive forum provisions of our restated certificateCertificate of incorporation.Incorporation. This may require significant additional costs associated with resolving such action in other jurisdictions and there can be no assurance that the provisions will be enforced by a court in those other jurisdictions.

DESCRIPTION OF UNITSTHE RIGHTS OFFERING

Subscription Rights

Basic Subscription Rights

We may issue units comprisedwill distribute to each holder of our common stock who is a record holder of our common stock on the Record Date, which is [●], at no charge, one or moreSubscription Right for every one share of common stock owned. The Subscription Rights will be evidenced by non-transferable Subscription Rights certificates. Each Subscription Right will entitle the Subscription Rights holder to purchase 2.152353 shares of common stock at the Initial Price, which shall be paid in cash, upon timely delivery 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 any applicable prospectus supplement, summarizes the material termsrequired documents and provisionspayment of the unitsSubscription Price. To the extent that we may offer under this prospectus. While the terms summarized below will apply generally to any units we may offer,Alternate Price is lower than the Initial Price, we will describe the particular termssell additional shares of any series of units in more detail in the applicable prospectus supplement. Ifcommon stock, but we indicate in the prospectus supplement, the terms of any units offered under that prospectus supplement may differ from the terms described below. Specific unit agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibitnot sell fractional shares, instead rounding down to the registration statement that includes this prospectus.

Each unit will be issued so that the holdernearest whole number 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 ofshares a holder of each included security. The unit agreement under which a unit is issued may providewould otherwise be entitled to purchase. While at this time the Company has no reason to believe the Alternate Price will decline such 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.

We will describe in the applicable prospectus supplement the terms of the series of units being offered, including:

We may issue units in such amounts and in such numbers of distinct series as we determine.

The provisions described in this section, as well as those described under “Description of Debt Securities,” “Description of Capital Stock” and “Description of Warrants” will apply to each unit, as applicable, and to any debt securities, common stock, preferred stock or warrant included in each unit, as applicable.

Unit Agent

The name and address of the unit agent for any units we offer will be set forth in the applicable prospectus supplement.

Enforceability of Rights by Holders of Units

Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.

DESCRIPTION OF WARRANTS

We may issue warrants to purchase debt securities, common stock or preferred stock. We may offer warrants separately or together with one or more additional warrants, debt securities, common stock, preferred stock 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:

FORMS OF SECURITIES

Each debt security, 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 will be issued 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 receiveexcess 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 debt securities, 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 debt securities, units and warrants in the form in which it was made. Any Excess Subscription Amount resulting from the reduction of one or more fully registered global securities thatthe Subscription Price from the Initial Price to the Alternate Price will be deposited withallocated towards the purchase of additional shares of common stock (either towards your Basic Subscription Right, if available, or towards the Over-Subscription Right if you have already exercised your Basic Subscription Right in full).

No Fractional Shares

We will not issue fractional shares of common stock in the Rights Offering. Subscription Rights holders will only be entitled to purchase a depositarywhole number of shares of common stock, rounded down to the nearest whole number of shares a holder would otherwise be entitled to purchase. Any Excess Subscription Amount resulting from the reduction of the Subscription Price from the Initial Price to the Alternate Price will be allocated towards the purchase of additional shares of common stock (either towards your Basic Subscription Right, if available, or towards the Over-Subscription Right if you have already exercised your Basic Subscription Right in full). The excess amount for any fractional shares of common stock will be returned to you as soon as practicable, in the form in which made. You will not receive interest or a deduction on any payments refunded to you under the Rights Offering.

Conditions to the Rights Offering

We may terminate the Rights Offering, in whole or in part, if at any time before completion of the Rights Offering there is any judgment, order, decree, injunction, statute, law or regulation entered, enacted, amended or held to be applicable to the Rights Offering that in the sole judgment of our board of directors would or might make the Rights Offering or its nominee identifiedcompletion, whether in whole or in part, illegal or otherwise restrict or prohibit completion of the Rights Offering. We may waive this condition and choose to proceed with the Rights Offering even if this occurs. If we terminate the Rights Offering, in whole or in part, all affected Subscription Rights will expire without value and all subscription payments in the applicable prospectus supplement and registeredform in which received by the subscription agent will be returned in the name of that depositaryform in which paid, without interest or nominee. In those cases, one or more global securities will be issued in a denomination or aggregate denominations equal to the portiondeduction, as soon as practicable. See also “—Expiration of the aggregate principal or face amountRights Offering and Extensions, Amendments and Termination.”

Method of the securities to be represented by global securities. UnlessExercising Subscription Rights

The exercise of Subscription Rights is irrevocable 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 amongcancelled or modified. Your Subscription Rights will not be considered exercised unless the depositary for the global security, the nominees of the depositarysubscription agent receives from you, your custodian bank, broker, dealer 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 holderall of the required documents properly completed and executed and your full Subscription Price payment in cash, as provided herein, prior to the Expiration Date of the Rights Offering, which is currently set to be 5:00 p.m., Eastern Time, on [●]. Subscription Rights holders may exercise their rights as follows:

Subscription by Registered Holders

Subscription Rights holders who are registered holders of our common stock as of the Record Date may exercise their Subscription Right by properly completing and executing the rights certificate together with any required signature guarantees and forwarding it, together with payment in full, as provided herein, of the Subscription Price for each share of common stock for which they subscribe, to the subscription agent at the address set forth under the subsection titled “—Delivery of Subscription Materials and Payment,” on or prior to the Expiration Date.

Subscription by DTC Participants

Banks, trust companies, securities representeddealers and brokers (each, a “Nominee”) that hold shares of our common stock on the Record Date as nominee for more than one beneficial owner may, upon proper showing to the subscription agent, exercise such beneficial owner’s Subscription Right through DTC on the same basis as if the beneficial owners were stockholders on the Record Date. Such Nominee may exercise the Subscription Right on behalf of the exercising beneficial owner through DTC’s PSOP Function on the “agents subscription over PTS” procedure by (1) providing a certification as to the aggregate number of Subscription Rights exercised by the global securitybeneficial owner on whose behalf such Nominee is acting, and (2) instructing DTC to charge the Nominee’s applicable DTC account for all purposes under the applicable indenture, warrant agreement or unit agreement. Except as described below, ownerssubscription payment for the new shares of beneficial interests in a global security will not be entitledcommon stock to havefacilitate 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 formfull subscription payment to the subscription agent. DTC must receive the subscription instructions and will not be consideredpayment for the new shares of common stock no later than the Expiration Date.

Subscription by Beneficial Owners

Subscription Rights holders who are beneficial owners or holdersof shares of our common stock as of the securities under the applicable indenture, 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 securityRecord Date 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 indenture, 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 indenture, 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.

Principal, premium, if any, and interest payments on debt securities, and any payments to holders with respect to warrants or units, represented by a global securitywhose shares are registered in the name of a depositarycustodian bank, broker, dealer or itsother nominee, will be madeor would prefer to have an institution conduct the transaction relating to the depositaryrights on their behalf, should instruct their custodian bank, broker, dealer or itsother nominee or institution to exercise their rights and deliver all documents and payment, on their behalf, prior to the Expiration Date. A Subscription Rights holder’s Subscription Rights will not be considered exercised unless the subscription agent receives from such Subscription Rights holder or the Subscription Rights holder’s custodian bank, broker, dealer, or other nominee or institution, as the case may be, all of the required documents and such holder’s full Subscription Price payment.

Method of Payment

You must timely pay the full Subscription Price, in U.S. currency, for the full number of shares of common stock at the Initial Price you wish to acquire pursuant to the exercise of rights (including any exercise of the Over-Subscription Rights, if available) by delivering:

Rights certificates received after the Expiration Date of the Rights Offering will not be honored, and we will return your payment to you in the form received as soon as practicable, without interest or deduction. The subscription agent will not accept uncertified personal checks, bank drafts or cashier’s checks as a means of payment.

The subscription agent will be deemed to receive payment upon:

If, on the Expiration Date, the Alternate Price is lower than the Initial Price, any Excess Subscription Amounts paid by a subscriber will be allocated towards the purchase of additional shares of common stock.

Instructions for Completing Your Subscription Rights Certificate

You should read the instruction letter accompanying the rights certificate carefully and strictly follow it. DO NOT SEND RIGHTS CERTIFICATES OR PAYMENTS TO THE COMPANY. We will not consider your subscription received until the subscription agent has received delivery of a properly completed and duly executed rights certificate and payment of the full subscription amount as set forth herein. The risk of delivery of all documents and payments is on you or your nominee, not us or the subscription agent.

The method of delivery of rights certificates and payment of the subscription amount to the subscription agent will be at the risk of the holders of rights, but, if sent by mail, we recommend that you send those certificates and payments by overnight courier or by registered mail, properly insured, with return receipt requested, and that a sufficient number of days be allowed to ensure delivery to the subscription agent and clearance of payment before the expiration of the subscription period.

Unless a rights certificate provides that the shares of common stock are to be delivered to the record holder of such rights or such certificate is submitted for the account of a bank or a broker, signatures on such rights certificate must be guaranteed by an “Eligible Guarantor Institution,” as such term is defined in Rule 17Ad-15 of the Securities Exchange Act of 1934 (an “Eligible Institution”), subject to any standards and procedures adopted by the subscription agent. See “—Medallion Guarantee May Be Required.”

Medallion Guarantee May Be Required

If you completed any part of the Subscription Rights certificate to provide that the common stock purchased pursuant to your exercise of Subscription Rights were to be (x) issued in a name other than that of the registered owner of the global security. None of us,holder, or any trustee, warrant agent, unit agent or(y) issued to an address other agent of ours, or any agent of any trustee, 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 expectthan that the depositary for any of the securities represented by a global security, upon receipt of any payment to holders of principal, premium, interest 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 recordsfront of the depositary. We also expect that paymentsSubscription Rights certificate, your signature on each Subscription Rights certificate must be guaranteed 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 registeredan Eligible Institution, such 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 trustee, 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.

PLAN OF DISTRIBUTION

We may sell securities:

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 amember firm commitment basis.

The distribution of the securities may be effected from time to time in one or more transactions:

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 theregistered national securities including the following:

If any underwriters or agents are utilized in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement or other agreement with them at the time of sale to them, and we will 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 dealer is utilized in the sale of the securities in respect of which this prospectus is delivered, we will sell such securities to the dealer, 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 a standby underwriting agreement with dealers, acting as standby underwriters. We may pay the standby underwriters a commitment fee for the securities they commit to purchase on a standby basis. If we do not enter into a standby underwriting arrangement, we may retain a dealer-manager to manage a subscription rights offering for us.

Remarketing firms, agents, underwriters, dealers and other persons may be entitled under agreements which they may enter into with us to indemnification by us against certain 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:

Certain agents, underwriters and dealers, and their associates and affiliates may be 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 underwriters 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 determine payments on such securities. Specifically, any underwriters may overallot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to 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 underwriterexchange 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 more than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to 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.

In compliance with the guidelinesmember of the Financial Industry Regulatory Authority, Inc., or FINRA,a commercial bank or trust company having an office or correspondent in the United States, or by a member of a Stock Transfer Association approved medallion program such as STAMP, SEMP or MSP subject to standards and procedures adopted by the subscription agent.

Subscription and Information Agent

The subscription agent and information agent for this Rights Offering is Broadridge Corporate Issuer Solutions, LLC. We will pay all fees and expenses of Broadridge related to the Rights Offering and have also agreed to indemnify Broadridge from certain liabilities that it may incur in connection with the Rights Offering. Broadridge can be contacted at the following address and telephone number:

Broadridge Corporate Issuer Solutions, LLC
Attn: BCIS Re-Organization Dept.
P.O. Box 1317
Brentwood, NY 11717-0718
Toll Free: 1-855-793-5068

Delivery of Subscription Materials and Payment

You should deliver your Subscription Rights certificate and payment of the Subscription Price, as provided herein, or, if applicable, nominee holder certifications, to the subscription agent by one of the methods described below:

Your delivery to an address or by any method other than as set forth above will not constitute valid delivery and we may not honor the exercise of your Subscription Rights.

You should direct any questions or requests for assistance concerning the method of subscribing for shares of common stock or for additional copies of this prospectus to the information agent.

Funding Arrangements; Return of Funds

Broadridge Corporate Issuer Solutions, LLC, the subscription agent, will hold funds received in payment for shares of common stock in a segregated account pending completion of the Rights Offering. The subscription agent will hold this money until the Rights Offering is completed or is withdrawn or terminated. If the Rights Offering is canceled for any reason, all subscription payments received by the subscription agent will be returned to subscribers, without interest or penalty, as soon as practicable.

Guaranteed Delivery

There is no guaranteed delivery period in connection with this Rights Offering, so you must ensure that you properly complete all required steps prior to 5:00 p.m., Eastern Time, on [●], unless we decide to extend the Expiration Date until some later time or terminate it earlier.

Notice to Beneficial Holders

If you are a broker, a trustee or a depositary for securities who holds shares of our common stock for the account of others as of the Record Date, you should notify the respective beneficial owners of such shares of the Rights Offering as soon as possible to find out their intentions with respect to exercising their Subscription Rights. You should obtain instructions from the beneficial owners with respect to their Subscription Rights, as set forth in the instructions we have provided to you for your distribution to beneficial owners. If a beneficial owner so instructs, you should complete the appropriate Subscription Rights certificates and submit them to the subscription agent with the proper payment. If you hold shares of our common stock for the account(s) of more than one beneficial owner, you may exercise the number of Subscription Rights to which all such beneficial owners in the aggregate maximum discount, commissionotherwise would have been entitled had they been direct record holders of our common stock on the Record Date, provided that you, as a nominee record holder, make a proper showing to the subscription agent by submitting the form entitled “Nominee Holder Certification” substantially in the form accompanying this prospectus. If you did not receive this form, you should contact the subscription agent to request a copy.

Beneficial Owners

If you are a beneficial owner of shares of our common stock or agency feeswill receive Subscription Rights through a custodian bank, broker, dealer or other items constituting underwriting compensationnominee, we will ask your custodian bank, broker, dealer or other nominee to notify you of the Rights Offering. If you wish to exercise your Subscription Rights, you will need to have your custodian bank, broker, dealer or other nominee act for you. If you hold shares of our common stock directly under your name in stock certificate(s) or in book-entry, or uncertificated, form, but would prefer to have your custodian bank, broker, dealer or other nominee act for you, you should contact your nominee and request it to effect the transactions for you. Your nominee may establish a deadline prior to the Expiration Date by which you must provide it with your instructions to exercise your Subscription Rights and payment for your shares.

To indicate your decision with respect to your Subscription Rights, you should complete and return to your custodian bank, broker, dealer or other nominee the form entitled “Beneficial Owners Election Form” substantially in the form accompanying this prospectus. You should receive the “Beneficial Owners Election Form” from your custodian bank, broker, dealer or other nominee with the other Rights Offering materials. If you wish to obtain a separate Subscription Rights certificate, you should contact the nominee as soon as possible and request that a separate Subscription Rights certificate be issued to you. You should contact your custodian bank, broker, dealer or other nominee if you do not receive this form but you believe you are entitled to participate in the Rights Offering. We are not responsible if you do not receive this form from your custodian bank, broker, dealer or nominee or if you receive it without sufficient time to respond.

No Revocation or Change

Once you submit the form of rights certificate to exercise any Subscription Rights, you may not revoke or change your exercise or request a refund of monies paid. All exercises of rights are irrevocable, even if you subsequently learn information about us that you consider to be unfavorable. You should not exercise your Subscription Rights unless you are certain that you wish to purchase additional shares of common stock at the Initial Price.

Non-Transferability of the Rights

The Subscription Rights granted to you are non-transferable and, therefore, may not be assigned, gifted, purchased, sold or otherwise transferred to anyone else. Notwithstanding the foregoing, you may transfer your Subscription Rights as required by operation of law; for example, a transfer of rights to the estate of the recipient upon the death of the recipient would be permitted. If the rights are transferred as permitted, evidence satisfactory to us that the transfer was proper must be received by us prior to the Expiration Date.

Issuance of Common Stock

All shares of our common stock that you purchase in the Rights Offering will be issued in book-entry, or uncertificated, form, meaning that you will receive a direct registration (DRS) account statement from our transfer agent reflecting ownership of these securities if you are a holder of record of shares or warrants. If you hold your shares of common stock in the name of a custodian bank, broker, dealer, or other nominee, DTC will credit your account with your nominee with the securities you purchased in the Rights Offering. Subject to state securities laws and regulations, we have the discretion to delay distribution of any FINRA member or independent broker-dealersecurities you may have elected to purchase by exercise of your Subscription Rights in order to comply with state securities laws.

Validity of Subscriptions

We will resolve all questions regarding the validity and form of the exercise of your Subscription Rights, including time of receipt and eligibility to participate in the Rights Offering. Our determination will be final and binding. Once made, subscriptions and directions are irrevocable, and we will not exceed 8%accept any alternative, conditional or contingent subscriptions or directions. We reserve the absolute right to reject any subscriptions or directions not properly submitted or the acceptance of which would be unlawful. You must resolve any irregularities in connection with your subscriptions before the subscription period expires, unless waived by us in our sole discretion. Neither the subscription agent nor we shall be under any duty to notify you or your representative of defects in your subscriptions. A subscription will be considered accepted, subject to our right to cancel the Rights Offering, only when a properly completed and duly executed Subscription Rights certificate and any other required documents and payment of the proceedsfull subscription amount have been received by the subscription agent and any defects or irregularities therein waived by us. Our interpretations of the terms and conditions of the Rights Offering will be final and binding.

Rights of Subscribers

You will have no rights as a holder of the shares of our common stock you purchase in the Rights Offering until shares are issued in book-entry form or your account at your broker, dealer, bank or other nominee is credited with the shares of our common stock purchased in the Rights Offering. You will have no right to revoke your subscriptions after you deliver your completed rights certificate, subscription payment, as provided herein, and any other required documents to the subscription agent.

Foreign Stockholders and Stockholders with Army Post Office or Fleet Post Office Addresses

The subscription agent will not mail rights certificates to you if you are a registered stockholder whose address is outside the United States or if you have an Army Post Office or a Fleet Post Office address. Instead, we will have the subscription agent hold the Subscription Rights certificates for your account. To exercise your Subscription Rights, you must notify the subscription agent prior to 11:00 a.m., Eastern Time, at least three (3) business days prior to the Expiration Date and establish to the satisfaction of the subscription agent that it is permitted to exercise your Subscription Rights under applicable law. If you do not follow these procedures by such time, your Subscription Rights will expire and will have no value. If you hold your shares in the name of a custodian bank, broker, dealer or other nominee, you should follow the instructions you receive from it, as described above.

No Board of Directors Recommendation

An investment in the Company’s common stock must be made according to your evaluation of your own best interests and after considering all of the information herein, including the section titled “Risk Factors” beginning on page 23 of this prospectus. Neither we nor our board of directors are making any offeringrecommendation regarding whether you should exercise your Subscription Rights.

Purchase Commitments

Robert W. Duggan, our Executive Chairman, Chief Executive Officer, and the beneficial owner of approximately 78.1% of our outstanding common stock prior to this Rights Offering, and Dr. Mahkam Zanganeh, our co-Chief Executive officer, President, a member of our Board of Directors, and the beneficial owner of approximately 6.0% of our issued and outstanding common stock prior to this Rights Offering, have each indicated that they intend to participate in the Rights Offering and subscribe for at least the full amount of their Basic Subscription Rights, but have not made any formal binding commitment to participate.

Shares of Common Stock Outstanding After the Rights Offering

The number of shares of our common stock that will be outstanding after the Rights Offering will depend on the number of shares of common stock that are purchased in the Rights Offering. Assuming no additional shares of common stock are issued by us prior to consummation of the Rights Offering and assuming all offered shares of common stock are sold in the Rights Offering at the Initial Price, we will issue approximately 476,190,476 shares of common stock. In that case, we will have approximately 697,432,201 shares of common stock outstanding after the Rights Offering. This would represent an increase of approximately 215% in the number of outstanding shares of common stock. To the extent that the Alternate Price is lower than the Initial Price, we will sell additional shares of common stock in the Rights Offering, and the number of shares of common stock outstanding after the Rights Offering will accordingly be higher.

Fees and Expenses

Neither we, nor the subscription agent, will charge a brokerage commission or a fee to Subscription Rights holders for exercising their rights. However, if you exercise your Subscription Rights through a custodian bank, broker, dealer or nominee, you will be responsible for any fees charged by your custodian bank, broker, dealer or nominee.

Questions About Exercising Subscription Rights

If you have any questions or require assistance regarding the method of exercising your Subscription Rights or requests for additional copies of this document or any document mentioned herein, you should contact the subscription agent at the address and telephone number set forth above under “— Delivery of Subscription Materials and Payment.”

No “Going Private” Transaction

The Rights Offering is not a transaction or series of transactions which has either a reasonable likelihood or a purpose of producing a “going private effect” as specified in Rule 13e-3 of the Exchange Act. Given the structure of the Rights Offering, as described in this prospectus, the Company will continue to be registered pursuant to Section 12 of the Exchange Act and intends to remain listed on the Nasdaq Global Market following completion of the Rights Offering.

Other Matters

The Company is not making the Rights Offering in any state or other jurisdiction in which it is unlawful to do so, nor is the Company distributing or accepting any offers to purchase any of our securities from Subscription Rights holders who are residents of those states or of other jurisdictions or who are otherwise prohibited by federal or state laws or regulations to accept or exercise the Subscription Rights. The Company may delay the commencement of the Rights Offering in those states or other jurisdictions, or change the terms of the Rights Offering, in whole or in part, in order to comply with the securities law or other legal requirements of those states or other jurisdictions. Subject to state securities laws and regulations, the Company also has the discretion to delay allocation and distribution of any securities you may elect to purchase by exercise of your Subscription Rights in order to comply with state securities laws. The Company may decline to make modifications to the terms of the Rights Offering requested by those states or other jurisdictions, in which case, if you are a resident in one of those states or jurisdictions or if you are otherwise prohibited by federal or state laws or regulations from accepting or exercising the Subscription Rights you will not be eligible to participate in the Rights Offering.

MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES

The following summary does not purport to be a complete analysis of all of the potential U.S. federal income tax considerations, and does not address any tax consequences arising under any state, local or non-U.S. tax laws or any other U.S. federal tax laws, including the U.S. federal estate or gift tax laws. This discussion applies only to holders who are U.S. persons (as defined below) and does not address all aspects of U.S. federal income taxation that may be relevant to holders in light of their particular circumstances or to holders who may be subject to special tax treatment under the Code, including, without limitation, holders who are dealers in securities or non-U.S. currency, non-U.S. persons, certain former citizens or long-term residents of the United States, insurance companies, tax-exempt organizations, banks, financial institutions or broker-dealers, holders who hold our common stock as part of a hedge, straddle, conversion or other risk reduction transaction, or holders who acquired our common stock pursuant to the exercise of compensatory stock options or otherwise as compensation.

This summary is of a general nature only and is not intended to constitute a complete analysis of all tax consequences relating to the receipt, exercise and expiration of the Subscription Rights, and the ownership and disposition of our common stock. It is not intended to constitute, and should not be construed to constitute, legal or tax advice to any particular holder. This discussion neither binds nor precludes the Internal Revenue Service (“IRS”) from adopting a position contrary to, or otherwise challenging, the positions addressed in this prospectus, and we cannot assure you that such a contrary position will not be asserted successfully by the IRS or adopted by a court if the position or matter was litigated. We have not sought, and will not seek, either (i) a ruling from the IRS or (ii) an opinion from legal counsel, in either instance regarding the tax considerations discussed herein. Holders should consult their own tax advisors as to the tax consequences in their particular circumstances.

For purposes of this discussion, a “U.S. person” means a beneficial owner of Subscription Rights that is:

If a partnership (including any entity treated as a partnership for U.S. federal income tax purposes) receives the Subscription Rights or holds the stock received upon exercise of the Subscription Right, the tax treatment of a partner in such partnership generally will depend upon the status of the partner and the activities of the partnership. Such a partner and the partnership are urged to consult their own tax advisors as to the U.S. federal income tax consequences of receiving the Subscription Rights and exercising (or allowing to expire) the Subscription Rights.

This discussion does not describe all of the tax considerations which may be relevant to a particular holder’s ownership of the shares of common stock received upon exercise of the Basic Subscription Rights or the Over-Subscription Rights.

EACH HOLDER OF SHARES OF OUR COMMON STOCK IS STRONGLY URGED TO CONSULT SUCH HOLDER’S OWN TAX ADVISORS REGARDING THE SPECIFIC FEDERAL, STATE, LOCAL AND NON-U.S. INCOME AND OTHER TAX CONSIDERATIONS OF THE RECEIPT AND EXERCISE OF THE SUBSCRIPTION RIGHTS, AND THE OWNERSHIP AND DISPOSITION OF OUR COMMON STOCK.

U.S. Federal Income Tax Considerations Applicable to the Receipt of Subscription Rights

Receipt of Subscription Rights

Under section 61(a)(3) of the Code, gross income includes “gains derived from dealings in property.” Under section 301 of the Code, “a distribution of property… made by a corporation to its stockholder with respect to its stock” is taxable as gross income to the extent that the distribution is made out of the corporation’s current or accumulated earnings and profits. If at the time of the distribution the corporation does not have current or accumulated earnings and profits, then the amount of the distribution is applied first as a reduction in the stockholder’s basis in its stock; the amount of any distribution in excess of the stockholder’s basis is treated as a capital gain from the sale or exchange of property.

Code section 305(a), however, provides that gross income does not include “the amount of any distribution of the stock of a corporation made by such corporation to its stockholders with respect to its stock.” For purposes of Code section 305, “stock” is defined in Code section 305(d)(1) to include rights to acquire such stock.

The general rule set forth in Code section 305(a) regarding nonrecognition is subject to certain exceptions, including if receipt by a holder of Subscription Rights is part of a “disproportionate distribution” as set forth in Code section 305(b)(2). A “disproportionate distribution” is a distribution or a series of distributions, including deemed distributions, that has the effect of the receipt of cash or other property by some holders and an increase in the proportionate interest of other holders in our assets or earnings and profits. During the last 36 months, we have made a distribution of Subscription Rights to holders of our common stock. Our common stock was then and is now our sole outstanding class of stock, and we have no current intention of issuing another class of stock or convertible debt. The fact that we have made a prior distribution of Subscription Rights within the last 36 months means that the 36-month safe harbor rule set forth in the Treasury Regulations will not apply and, therefore, the distribution of Subscription Rights will not be presumed to not result in the receipt of cash or property by some stockholders and an increase in the proportionate interest of other stockholders. We also have outstanding options (issued as equity awards) which could cause, under certain circumstances that cannot be predicted currently, the receipt of Subscription Rights pursuant to this prospectusRights Offering to be part of a disproportionate distribution. The Company believes that the distribution of Subscription Rights in this Rights Offering is not likely to constitute an increase in the proportionate interest of some stockholders in the assets or earnings and profits of the Company for purposes of Code section 305(b)(2) based on the fact that all of our stockholders will receive rights in the Rights Offering based upon their respective ownership of our common stock. The Company also intends to take the position that the outstanding options (issued as equity awards) and their potential exercise do not cause the Subscription Rights issued pursuant to this Rights Offering to be part of a disproportionate distribution, but there can be no assurances in this regard.

Our position regarding the tax-free treatment of the receipt of Subscription Rights in this Rights Offering is not binding on the IRS or the courts, and there can be no assurance that the IRS or any applicable prospectus supplement.

LEGAL MATTERS

Unlesscourt would agree. If this position were finally determined to be incorrect, whether on the applicable prospectus supplement indicatesbasis that the issuance of the subscriptions rights is a “disproportionate distribution” or otherwise, the validityfair market value of the securitiesSubscription Rights would be taxable to holders of our common stock as a dividend on the date of the distribution to the extent of the holder’s pro rata share of our current and accumulated earnings and profits, if any, with any excess being treated as a return of capital to the extent of the holder’s basis in shares of our common stock and thereafter as capital gain. Although no assurance can be given, it is anticipated that we will not have current and accumulated earnings and profits through the end of 2022.

The following discussion assumes that the receipt by a holder of Subscription Rights with respect to such holder’s common stock pursuant to this Rights Offering is non-taxable for U.S. federal income tax purposes.

Tax Basis in the Subscription Rights

A holder’s tax basis in its Subscription Rights will depend on the relative fair market value of the Subscription Rights received by such holder and the common stock owned by such holder at the time the Subscription Rights are distributed. If either (i) the fair market value of the Subscription Rights on the date such Subscription Rights are distributed is equal to at least 15% of the fair market value on such date of the common stock with respect to which the Subscription Rights are received or (ii) the holder elects, in its U.S. federal income tax return for the taxable year in which the Subscription Rights are received, to allocate part of its tax basis in such common stock to the Subscription Rights, then upon exercise of the Subscription Rights (and upon exercise, between the old stock and the stock received upon the exercise of the rights), the holder’s tax basis in the common stock will be allocated between the common stock and the Subscription Rights in proportion to their respective fair market values on the date the Subscription Rights are distributed. If the Subscription Rights received by a holder have a fair market value that is less than 15% of the fair market value of the common stock owned by such holder at the time the Subscription Rights are distributed, the holder’s tax basis in its Subscription Rights will be zero unless the holder elects to allocate its adjusted tax basis in the common stock owned by such holder in the manner described in the previous sentence. The fair market value of the Subscription Rights on the date the Subscription Rights are received is uncertain, and we have not obtained, and do not intend to obtain, an appraisal of the fair market value of the Subscription Rights as of that date. Therefore, you should consult with your tax advisor to determine the proper allocation of basis between the Subscription Rights and the shares of common stock with respect to which the Subscription Rights are received.

Expiration of Subscription Rights

A holder that allows the Subscription Rights received in the Rights Offering to expire will not recognize any gain or loss, and the tax basis in the common stock owned by such holder with respect to which such Subscription Rights were distributed will be equal to the tax basis in such common stock immediately before the receipt of the Subscription Rights in the Rights Offering.

Exercise of Subscription Rights and Holding Period

A holder will not recognize any gain or loss upon the exercise of the Subscription Rights received in the Rights Offering. The tax basis in the common stock acquired through exercise of the Subscription Rights will equal the sum of the Subscription Price for the common stock and the holder’s tax basis, if any, allocated to the rights as described above. The holding period for the common stock acquired through exercise of the Subscription Rights will begin on the date the Subscription Rights are exercised. Holders who exercise Subscription Rights after disposing of all of the shares of the common stock owned by such holder should consult with their own tax advisor regarding the allocation of tax basis.

U.S. Federal Income Tax Considerations Applicable to Our Common Shares

Distributions

Distributions with respect to shares of our common stock acquired upon exercise of Subscription Rights will be taxable as dividend income when actually or constructively received to the extent of our current or accumulated earnings and profits as determined for U.S. federal income tax purposes. The excess will generally be treated first as a return of capital to the extent of a holder’s adjusted tax basis in its shares of our common stock, and, thereafter, as capital gain.

Dividend income received by certain non-corporate holders with respect to shares of our common stock generally will be “qualified dividends” subject to preferential rates for U.S. federal income tax purposes, provided that the holder meets applicable holding period and other requirements. Subject to similar exceptions for short-term and hedged positions, dividend income on our shares of common stock paid to holders that are domestic corporations generally will potentially qualify for the dividends-received deduction.

Dispositions

A holder which sells or otherwise disposes of shares of common stock acquired upon exercise of Subscription Rights in a taxable transaction generally will recognize capital gain or loss equal to the difference between the amount realized and such holder’s adjusted tax basis in the shares. Such capital gain or loss will be long-term capital gain or loss if a holder’s holding period for such shares is more than one year at the time of disposition. Long-term capital gain of a non-corporate holder is generally taxed at preferential U.S. income tax rates. The deductibility of capital losses is subject to limitations.

Information Reporting and Backup Withholding

U.S. backup withholding (currently at a rate of 24%) is imposed upon certain distributions (or deemed distributions) to persons who fail (or are unable) to furnish the information required pursuant to U.S. information reporting requirements. Distributions (or deemed distributions or similar transactions) to a holder will generally be exempt from backup withholding, provided the holder meets applicable certification requirements, including (i) providing us with such holder’s U.S. taxpayer identification number (e.g., an individual’s social security number or individual taxpayer identification number, or an entity’s employer identification number, each a “TIN”) or (ii) otherwise establishing an exemption (e.g., an exemption from backup withholding as a corporate payee), in each instance on a properly completed IRS Form W-9, certifying under penalties of perjury that, among others, such TIN or exemption is correct, together with such other certifications as may be required by law.

Backup withholding does not represent an additional tax. Any amounts withheld from a payment to a holder under the backup withholding rules will generally be allowed as a credit against such holder’s U.S. federal income tax liability, and may entitle such holder to a refund, provided the required information and returns are timely furnished by such holder to the IRS.

AS INDICATED ABOVE, THE FOREGOING DISCUSSION IS FOR GENERAL INFORMATION PURPOSES ONLY AND SHOULD NOT BE VIEWED AS COMPLETE OR COMPREHENSIVE TAX ADVICE. HOLDERS RECEIVING A DISTRIBUTION OF STOCK RIGHTS CONTEMPLATED IN THIS RIGHTS OFFERING AND HOLDERS CONSIDERING THE PURCHASE OF OUR COMMON STOCK BY EXERCISING SUCH STOCK RIGHTS ARE URGED TO CONSULT THEIR OWN TAX ADVISORS REGARDING THE APPLICATION OF THE U.S. FEDERAL TAX LAWS TO THEIR PARTICULAR SITUATIONS AND THE APPLICABILITY AND EFFECT OF STATE, LOCAL AND NON-U.S. LAWS TO THEM. 

PLAN OF DISTRIBUTION

We are distributing rights certificates and copies of this prospectus to those persons who were holders of our common stock on [●], the Record Date for the Rights Offering, following the effective date of the registration statement of which this prospectus is being deliveredforms a part. We have not employed any brokers, dealers or underwriters in connection with the solicitation or exercise of rights in the Rights Offering and no commissions, fees or discounts will be passedpaid in connection with the Rights Offering. While certain of our directors, officers and other employees may solicit responses from you, those directors, officers and other employees will not receive any commissions or compensation for their services other than their normal compensation, and will not register with the SEC as brokers in reliance on certain safe harbor provisions contained in Rule 3a4-1 under the Exchange Act.

Delivery of Subscription Rights

As soon as practicable after the Record Date for the Rights Offering, we will distribute the rights, rights certificates and copies of this prospectus to individuals who owned shares of common stock on 4:00 p.m., Eastern Time, on [●]. If your shares are held in the name of a custodian bank, broker, dealer or other nominee, then you should send your subscription documents and subscription payment to that record holder. If you are the record holder, then you should send your subscription documents, rights certificate, and subscription payment to the subscription agent, Broadridge Corporate Issuer Solutions, LLC, at the following address. If sent by mail, we recommend that you send documents and payments by registered mail, properly insured, with return receipt requested, and that a sufficient number of days be allowed to ensure delivery to the subscription agent. Do not send or deliver these materials to the Company.

In the event that the Rights Offering is not fully subscribed, holders of rights who exercise all of their rights pursuant to their Basic Subscription Right will have the opportunity to subscribe for additional shares of common stock pursuant to the Over-Subscription Right. See further the section titled “The Rights Offering” beginning on page 40.

We have not agreed to enter into any standby or other arrangement to purchase or sell any rights or any of our securities. Robert W. Duggan, our Executive Chairman, Chief Executive Officer, and the beneficial owner of approximately 78.1% of our outstanding common stock prior to this Rights Offering, and Dr. Mahkam Zanganeh, our co-Chief Executive Officer, President, a member of our Board of Directors, and the beneficial owner of approximately 6.0% of our issued and outstanding common stock prior to this Rights Offering, have each indicated that they intend to participate in the Rights Offering and subscribe for at least the full amount of their Basic Subscription Rights, but have not made any formal binding commitment to participate.

We have not entered into any agreements regarding stabilization activities with respect to our securities. If you have any questions, you should contact the information agent at Broadridge Corporate Issuer Solutions, LLC, Attn: BCIS Re-Reorganization Dept., P.O. Box 1317, Brentwood, NY 11717-0718, by telephone at 1-855-793-5068 or by email at shareholder@broadridge.com. We have agreed to pay Broadridge Corporate Issuer Solutions, LLC a fee plus certain expenses, which we estimate will total approximately $50,000. We estimate that our total expenses in connection with the Rights Offering will be approximately $500,000.

Other than as described herein, we do not know of any existing agreements between any stockholder, broker, dealer, underwriter or agent relating to the sale or distribution of the shares of common stock.

LEGAL MATTERS

Baker & Hostetler, LLP will pass upon the validity of any securities we offer by Wilmer Cutler Pickering Hale and Dorr LLP.this prospectus.

EXPERTS

The financial statements as of and for the year ended December 31, 2021 incorporated by reference in this prospectus by reference to the Annual Report included in the Company’s Current Report on Form 8-K filed with the Securities and Exchange Commission on September 29, 202010-K/A for the eleven monthsyear ended December 31, 20192021 have been so been incorporated in reliance on the report  (which contains an explanatoryemphasis of matter paragraph relatingrelated to the Company’s abilityrequirement for additional financing to continue as a going concernfund future operations and management’s plans as described in Note 23 to the consolidated financial statements) of PricewaterhouseCoopers LLP (a Delaware limited liability partnership), an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

The financial statements as of and for the year ended December 31, 2020 incorporated by reference in this prospectus by reference to the Annual Report on Form 10-K/A for the year ended December 31, 2021 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP (a United Kingdom entity), an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting. 

SUMMIT THERAPEUTICS INC.

$200,000,000

Debt Securities

Common Stock

Preferred Stock

Units

Warrants

PROSPECTUS

            , 2020INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information into this prospectus. This means that we can disclose important information about us and our financial condition to you by referring you to other documents filed separately with the SEC. The information incorporated by reference is considered to be a part of this prospectus, except any information that is superseded by information that is included in a document subsequently filed with the SEC.