PMV Pharmaceuticals has reported a 43% response rate in a midphase ovarian cancer trial, putting the biotech on a track it believes will lead to a filing for FDA approval in the first quarter of 2027.
The phase 1/2 trial is testing rezatapopt, a small molecule p53 reactivator designed to restore wild-type tumor-suppressor function. PMV began dosing patients in the phase 2 portion of the trial early last year. The trial is enrolling patients with a range of solid tumors with a TP53 Y220C mutation. PMV has named ovarian cancer as its lead indication.
At an interim analysis, PMV reported that 19 of the 44 ovarian cancer patients had responded to therapy. One patient had a complete response. The other responses were partial and included one unconfirmed response. The median duration of response in ovarian cancer was 7.6 months.
“It is very encouraging to see the depth and durability of tumor shrinkage observed across the ovarian cancer cohort in our phase 2 study,” Deepika Jalota, chief development officer at PMV, said on a call with investors to discuss the data. “Not only did we observe deep responses, we see that responses were rapid and durable in our ovarian cancer patients to date.”
Based on the results, PMV plans to recruit another 20 to 25 ovarian cancer patients before completing enrollment in the first quarter of next year. PMV is aiming to reach primary analysis for the cohort in the fourth quarter of 2026 and file for FDA approval in the first quarter of 2027. The biotech’s cash runway extends into the first quarter of 2027.
PMV estimates there are about 1,700 second-line and later ovarian cancer patients with TP53 Y220C mutations in the U.S. and five major European markets. The estimate translates into a U.S. market opportunity of $350 million to $420 million, Jalota said. Globally, the market tops out at $630 million.
The company is targeting a platinum-resistant ovarian cancer market that is served by chemotherapy, AbbVie’s Elahere, and AstraZeneca and Daiichi Sankyo’s Enhertu. Jalota said chemotherapy has limited efficacy and Elahere and Enhertu are limited to smaller biomarker-defined subsets of the ovarian cancer population. PMV is betting that the limitations of existing therapies leave room for rezatapopt.
“Rezatapopt offers a distinct alternative to both standard of care and emerging therapies as an oral, biomarker-directed chemo-alternative therapy with strong efficacy that combines convenient administration with a manageable safety profile, positioning it as a compelling potential option for this patient population,” Jalota said.
Beyond ovarian cancer, PMV has phase 2 data in other solid tumors to inform its plans to expand the label for rezatapopt post-approval. The company saw the highest response rate—60%—in endometrial cancer, but the cohort only included five patients. The response rates in larger cohorts of breast and lung cancer patients were around 20%.
Shares in PMV rose 14% to $1.83 in premarket trading.