ORIC Falls After Hours On Safety Concerns Around Prostate Cancer Candidate At Higher Doses

• An exposure-response analysis showed a statistically significant link between higher drug exposure and increased toxicities as well as more frequent treatment interruptions and discontinuations, the company said.
• ORIC said it plans to launch its global late stage trial in metastatic castration-resistant prostate cancer patients who were previously treated with abiraterone using the 400 mg dose in the first half of 2026.

Shares of ORIC Pharmaceuticals, Inc. (ORIC) fell 25% after hours on Tuesday after the company announced that it has selected a 400 mg once-daily dose of its investigational drug for a later stage trial after tolerability concerns emerged during an early stage study.

In the early-stage trial involving certain previously treated patients with metastatic castration-resistant prostate cancer, the higher 600 mg dose of rinzimetostat produced a “modestly higher rate of adverse events and dose modifications” compared with the 400 mg level when administered with darolutamide, the company said.

An exposure-response analysis showed a statistically significant link between higher drug exposure and increased toxicities as well as more frequent treatment interruptions and discontinuations, favoring the lower dose on safety grounds, it added.

At the selected 400 mg dose, a grade 3 treatment-related adverse event was observed though the majority were mild, Oric said. Grade 3 treatment-related adverse events are severe, significant toxicities that are not immediately life-threatening. The company also reported one discontinuation in the early-stage  trial. However, the company CEO Jacob M. Chacko said that the drug demonstrated a "cleaner safety profile than competitor regimens."

ORIC said it plans to launch its global late stage trial in metastatic castration-resistant prostate cancer patients who were previously treated with abiraterone using the 400 mg dose in the first half of 2026.  

“Early efficacy data… are suggestive of meaningful and durable clinical benefit for rinzimetostat in combination with darolutamide compared to competitor data and historical outcomes with approved therapies,” the company said.

How Did Retail Traders React?

On Stocktwits, retail sentiment around ORIC stock jumped from ‘bearish’ to ‘extremely bullish’ territory over the past 24 hours, while message volume jumped from ‘normal’ to ‘extremely high’ levels.

ORIC stock has gained 127% over the past 12 months. 

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