Oric Pharmaceuticals (NASDAQ:ORIC) experienced a sharp market reaction this week after presenting early clinical data for its prostate cancer candidate rinzimetostat. Shares fell 41% on Wednesday and were down a further more than 2% on Thursday morning following the release of results that matched, but did not outperform, a competing therapy.
The company disclosed dose-optimization results from a study evaluating 400 mg of rinzimetostat in combination with darolutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) who had prior treatment with abiraterone. The trial enrolled 18 patients with a median baseline prostate-specific antigen (PSA) level of 26 ng/ml. All participants had received abiraterone previously, and 39% had also received docetaxel.
At a median follow-up of 4.9 months, the rinzimetostat-darolutamide combination produced a confirmed PSA50 response rate of 33%. Reported radiographic progression-free survival (rPFS) rates were 93% at 3 months, and 84% at both the 4- and 5-month landmarks.
Oric compared these outcomes with results reported for Pfizer's mevrometostat administered with enzalutamide. In that dataset, mevrometostat showed a 42.9% confirmed PSA50 response rate in 14 patients at a median follow-up of 9.4 months. The rPFS rates for the mevrometostat regimen were 92% at 3 months, 92% at 4 months, and 84% at 5 months.
Analyst reactions varied. Wolfe Research applied a Peer-perform rating and highlighted duration-on-treatment differences, stating: "Mevro pts appear to stay on tx longer than rinzi pts. At every landmark (months 3, 6, 9, 12), the mevro KM estimate is higher. This holds for the combined 2A/2C comparison from mevro’s Phase I." Baird retained an Outperform rating and emphasized safety, commenting that "the combination continues to show a potentially best-in-class safety profile." HC Wainwright reiterated a Buy rating with a $25 price target and cited physician preference in its rationale: "roughly 80% of physicians indicated that they would preferentially prescribe the rinzimetostat combo over mevrometostat + Extandi due to the safety profile."
Looking ahead, Oric plans to initiate the Phase 3 Himalayas-1 trial in the first half of 2026. The company will likely need to address how its regimen compares to competitors in larger, longer studies as it advances into late-stage testing.
Context and implications
- Market reaction was driven by investor interpretation that the new data did not provide a clear efficacy advantage versus an existing rival regimen.
- Analysts highlighted contrasting elements of the datasets: the competing program showed higher confirmed PSA50 and longer follow-up, while Oric's program was noted for its safety profile by some sell-side firms.
- The path forward centers on the planned Phase 3 start in H1 2026 and how subsequent data will be positioned against the competitive landscape.