Repare: Potential Of Camonsertib With Several Shots On Goal

Summary

• Repare Therapeutics presented preliminary results from the phase 1 MYTHIC study using the lunresertib and camonsertib combination for the treatment of patients with multiple solid tumor types.
• The biotech plans to complete the phase 1 expansion portion of the phase 1 MYTHIC study and release results in 2024. Plus, potentially initiating late-stage trials in 2024 thereafter.
• Highly impressive data from the lunresertib and camonsertib combination was observed in patients with gynecological tumors, where the OR was 60%.
• Partnerships have already been established with Roche and Bristol-Myers Squibb in advancing the synthetic lethality technology approach that Repare has as part of its arsenal.
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Repare Therapeutics (NASDAQ:RPTX) has made great progress in advancing its pipeline. That's because it presented preliminary results from a phase 1 study using lunresertib in combination with camonsertib for the treatment of patients with multiple solid tumor types. Why I believe this finding has potential for investors is because of several reasons. The first reason is that this biotech intends to complete the phase 1 expansion portion of this study and then have results released from it in 2024. The second reason is that if everything goes according to plan, then it will be able to initiate late-stage trials for this program. The third and final reason is that it saw very impressive data with respect to an unmet medical need, which is that this combination did well in patients with gynecological tumors. The premise of this biotech is not just with the advancement of camonsertib being explored in this combination with lunresertib. Camonsertib is also being explored in several other clinical studies alone and in combination with other drugs in collaboration with Roche (OTCQX:RHHBY) for the treatment of patients with several solid tumor types. How all these clinical trials end up playing out remains to be seen, but should data turn out well, then Repare is eligible to receive milestone payments from several of such programs.

Camonsertib Combination Study Has Huge Potential Based On Preliminary Data

The first program to look into would be the advancement of camonsertib, which is being explored in combination with lunresertib for the treatment of patients with several solid tumor types, in the ongoing phase 1 MYTHIC study. This first human phase 1 study uses lunresertib as a monotherapy or in combination with camonsertib for the treatment of patients with advanced solid tumors harboring the CCNE1 amplification or FBW7 or PPP2R1A deleterious alterations. This MYTHIC study was split into the following modules:

• Module 1 - lunresertib given alone as a monotherapy
• Module 2 - lunresertib given in combination with camonsertib

Proof-of-concept data was presented at the AACR-NCI-EORTC medical conference, whereby a total of 67 patients were enrolled in Module 1 and then approximately 59 patients were enrolled in Module 2. It is important to note that this preliminary data was presented with a cutoff date of September 5th 2023. The overall response achieved with the recommended phase 2 dose was 33.3% [18 patients evaluated]. However, the OR across all patients dosed was 23.6%. Since the release of results, the stock has been cut in half by 50% or more. I believe value still exists here because of what it was able to obtain with respect to this combination targeting patients specifically with gynecological tumors. With 10 evaluable patients with gynecological tumors, who were given the recommended phase 2 dose [RP2D], the overall response was 60%. This is what was achieved, especially given that these were very sick patients to begin with whereby they took an average of 3 and up to 9 prior lines of treatment. This one target saw a greatly improved OR compared to the entire overall solid tumor patient population. The notion here is that if this biotech can put its focus towards this specific solid tumor subtype, then it will do better in the long run. Not only that, but this was only preliminary data that was released from this phase 1 MYTHIC study. Repare Therapeutics intends to release results from the expansion portions of this phase 1 study in 2024. In addition, it is likely to be able to initiate late-stage trials shortly thereafter. These are several reasons why I believe that this biotech still has value despite the stock price falling. Especially, when it comes to the gynecological tumor patients seeing a high OR of 60%.

Camonsertib Additional Shots On Goal Could Also Bring Shareholder Value

The thing is that Repare Therapeutics established a deal with Roche, who is now responsible for camonsertib advancement in clinical studies. Such a collaboration deal for this clinical candidate was established back in June of 2022. One important thing to note is that the combination of lunresertib and camonsertib targeting multiple solid tumor types in the phase 1 study, which I noted above, is not included as part of the collaboration agreement between both of these companies. In other words, Repare is the entire party responsible for funding and advancing the combination I highlighted in the other subsection above. Having said that, there are several studies that are ongoing in collaboration with Roche. Three studies to note, being done with this big pharmaceutical company, are TAPISTRY, ATTACC, and Morpheus Lung. These clinical studies are as follows:

• Phase 2 TAPISTRY study : Open-label, multi-cohort study arm incorporating camonsertib monotherapy arm to treat genomic defined solid tumor patients, except non-small cell lung cancer [NSCLC] patients
• Phase 1/2 Morpheus Lung study : Open-label, multi-center, randomized study incorporating camonsertib + TECENTRIQ [Atezolizumab] arm to treat patients with metastatic non-small cell lung cancer [mNSCLC]
• Phase 1/2 ATTACC study : Open-label dose escalation and expansion study, using camonsertib in combination with PARP inhibitors Niraparib and Olaparib in patients with molecularly selected solid tumors

With respect to the TAPISTRY study, Repare is eligible to receive $40 million upon dosing of the first patients with camonsertib. From there, it could be eligible for an additional $15 million if such a study becomes a registrational one. In terms of the ATTACC study, Repare received a $4 million from Roche under their respective agreement and could earn milestone payments upon initiation of registrational studies or ongoing studies that convert to such registrational studies for specific tumor types.

Financials

According to the 10-Q SEC Filing, Repare Therapeutics had cash and cash equivalents and marketable securities of $280.7 million as of June 30, 2023. It has this much cash on hand primarily because of the Roche deal. Why is that? That's because the formation of this collaboration agreement brought in a $125 million upfront, nonrefundable payment. The company deal was revised in April of 2023 and as such, Repare could be eligible to earn up to $1.172 billion in potential clinical, regulatory, commercial and sales milestones. On top of royalties obtained on global net sales of products marketed that will range from high single-digits to high-teens. Repare had also established a deal with Bristol-Myers Squibb (BMY), however, the small-cap biotech only received $65 million as an upfront payment. Also, such a deal was established several years ago back in May of 2020. Repare Therapeutics should be good to fund its company for quite some time now, though. I state this because it believes that with the $280.7 million in cash on hand, it should be able to fund its operations into 2026.

Risks To Business

There are several risks that investors should be aware of before investing in Repare Therapeutics. The first risk to consider would be with respect to the combination of lunresertib and camonsertib, which is being evaluated in patients with multiple solid tumor types. That's because additional results from the phase 1 MYTHIC study, evaluating this combination for the treatment of this patient population, are expected in 2024. There is no assurance that results from this study will end up being positive, nor that late-stage trials will be started for this program thereafter. A second risk to consider would be with respect to the collaboration agreement with Roche, which is advancing several studies using camonsertib alone and in combination with other drugs. There is no guarantee that any of these studies will end up being successful in using this drug. In addition, should none of the ongoing studies produce adequate enough clinical data, then Roche could possibly terminate the collaboration Agreement.

That would not only put the camonsertib program back on the shoulders of Repare Therapeutics, but it would also mean the loss of being able to obtain milestone payments from it. A third risk to consider would be with respect to the collaboration agreement made between it and Bristol-Myers Squibb. At the moment, Repare is not receiving a lot of money in terms of milestone payments. However, as the program progressed it could be eligible for additional funds. In May of 2023, it was noted that the big pharma exercised its option for a third druggable target, and separately triggered a $1 million payment from a prior exercised drug.

Still, the risk here is that should this program not end up going well in the clinic, then Bristol-Myers Squibb could terminate this partnership at any moment without cause. This would mean the loss of being able to obtain any additional milestone payments as part of the collaboration deal. The fourth and final risk to consider would be with respect to IND candidates RP-1664 and RP-3467, which are both expected to enter the clinic in 2024. There is no assurance that IND filings will be accepted, nor that such phase 1 human studies are to be initiated. Even if such studies are ultimately given the green light, there is no assurance that positive results will be achieved.

Conclusion

Repare Therapeutics has made great progress in being able to advance the use of lunresertib and camonsertib for its pipeline. With respect to lunresertib it is possible that it can do well in combination with camonsertib for treating genomic-defined solid tumors, especially with respect to the targeting of gynecological disorders whereby it saw an OR of 60%. If this finding can be further investigated, then this might be a good population for Repare to focus on. However, it still expects to release additional results from the phase 1 MYTHIC study for several solid tumor types in 2024 anyway, which is a catalyst to look forward to. Other shots on goal for camonsertib are with respect to the ongoing studies being done in collaboration with Roche. That's because camonsertib is being combined with other drugs to treat several genomic-defined solid tumor types. I noted several of these studies above and these are additional shots on goal as it relates to the advancement of camonsertib. Lunresertib is also being explored across several other studies as well, which provides additional shots on goal.

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Analyst’s Disclosure: I/we have no stock, option or similar derivative position in any of the companies mentioned, and no plans to initiate any such positions within the next 72 hours. I wrote this article myself, and it expresses my own opinions. I am not receiving compensation for it (other than from Seeking Alpha). I have no business relationship with any company whose stock is mentioned in this article.