THRX Theseus Pharmaceuticals Inc

The first question on page 5 set forth in the section of the Offer to Purchase entitled “Summary Term Sheet” is hereby amended and restated in its entirety to read as follows:

Yes. You will only receive payments with respect to your CVRs if (i) a Disposition Agreement entered into during the Disposition Period results in Net Proceeds and/or (ii) any net savings versus the Closing Net Cash are realized between the Closing Date and the end of the Disposition Period. If none of the events described in clauses (i) or (ii) above occur, you will receive only the Cash Amount for your Shares and no payments with respect to your CVRs.

The co-offerors estimate that the amount that will be payable under the CVRs is most likely $0.00 per CVR, consisting of $0.00 per CVR in Disposition Proceeds and $0.00 per CVR in Further Savings Proceeds.

The co-offerors’ estimate of the Disposition Proceeds is based on the co-offerors’ assessment of the CVR Products together with Theseus’ independent estimate. The CVR Products are early-stage product candidates for which there are no plans to further advance in development. Theseus conducted an extensive business development process throughout 2023 in an effort to out-license, regionally or globally, THE-349, the most advanced CVR Product. Following outreach to more than 50 parties, Theseus received no proposals. The co-offerors believe, based on their experience operating and investing in biotechnology companies, that the Disposition Proceeds will most likely be $0.00 because (i) Theseus’ business development efforts were unsuccessful, (ii) market conditions have not substantially changed since Theseus’ business development efforts, and (iii) the CVR Products beyond THE-349 are even less advanced than THE-349. Even if market conditions were to change for the better, there would still be significant uncertainty regarding co-offerors’ ability to attract a potential acquirer for the CVR Products and, even if co-offerors were to be successful in negotiating transaction terms with a potential acquirer of the CVR Products, whether any potential acquirer of the CVR Products would be able to (i) initiate and complete successful nonclinical studies and clinical trials for any product related to or based upon the CVR Products, (ii) conduct sufficient clinical trials or other studies to support the approval and commercialization of any product related to the CVR Products, (iii) demonstrate to the satisfaction of the U.S. Food and Drug Administration and similar foreign regulatory authorities the safety and efficacy and acceptable risk-to-benefit profile of any product related to the CVR Products, (iv) seek and obtain regulatory marketing approvals for any product related to the CVR Products, (v) establish and maintain supply and manufacturing relationships with third parties to ensure adequate and legally compliant manufacturing of bulk drug substances and drug products to maintain that supply, (vi) launch and commercialize any product candidates that were to obtain marketing approval and, if launched, successfully establish a sales, marketing and distribution infrastructure, (vii) demonstrate the necessary safety data post-approval to ensure continued regulatory approval, (viii) demonstrate the actual and perceived benefits of any product related to the CVR Products, if approved, relative to existing and future alternative therapies based upon availability, cost, risk and safety profile, drug-drug interactions, ease of administration, side effects and efficacy, (ix) obtain coverage and adequate product reimbursement from third-party payors, including government payors, (x) achieve market acceptance for any approved products, (xi) address any competing technological and market developments, (xii) negotiate favorable terms in any collaboration, licensing or other arrangements into which such acquirer may enter in the future and perform its obligations under such collaborations, (xiii) establish, maintain, protect and enforce intellectual property rights related to the CVR Products and (xiv) attract, hire and retain qualified personnel, among other unknowns.

The co-offerors estimate that the amount that will be payable under the CVRs with respect to the Further Savings Proceeds is based on: (i) co-offerors’ extensive experience winding down biotechnology companies and clinical studies; and (ii) factors that may occur within 180 days following the Closing Date, such as the incurrence of unknown or unforeseen liabilities, such as unanticipated legal costs, clinical study wind-down costs, invoices from vendors, and costs resulting from any regulatory-related matters. The co-offerors believe that it is more likely than not that there are unknown and unforeseen liabilities that will arise during the 180 days following the Closing Date that would offset any potential Further Savings Proceeds. By way of example, if Theseus’ Estimated Costs Post-Merger Closing were approximately $1.0 million, and none of such costs were incurred by the Surviving Corporation, the net savings would be $1.0 million, or approximately $0.01 per CVR. Conversely, if all or more of these costs were incurred by the Surviving Corporation, the net savings would be $0, or $0.00 per CVR.

In considering whether to tender your Shares in the Offer, you should consider that it is entirely possible that no cash will be distributed to the holders of the CVR under the terms of the CVR Agreement.

The second paragraph on page 28 set forth in the section of the Offer to Purchase entitled “The Tender Offer” is hereby amended and restated in its entirety to read as follows:

Previously filed

Filed Herewith