Faeth reports positive Phase 2 topline data for PIKTOR in endometrial cancer, plans Phase 3

Faeth Therapeutics announced topline results on November 9, 2026 from its Phase 2 trial of PIKTOR, an investigational oral combination of serabelisib and sapanisertib, paired with paclitaxel in patients with advanced endometrioid endometrial cancer carrying a PI3K/AKT/mTOR pathway mutation who had received at least one prior therapy. The trial, known as FTH-PIK-201 (NCT06463028, GOG-3111), is being conducted in collaboration with The GOG Foundation.¹

As of an October 30, 2026 data cut, the confirmed objective response rate was 33%, rising to 44% among patients with a PIK3CA mutation.¹ Among the 42 treated patients, estimated median progression-free survival was 7.4 months, with a 62% six-month PFS rate.¹ Disease control rate was 83%.¹

On safety, as of an October 23, 2026 cut, hyperglycemia occurred in 12% of patients and stomatitis in 21%, with only 2% grade 3 events for each.¹ Two patients discontinued due to treatment-related adverse events, and there were no treatment-related deaths.¹ Overall, 64% had a grade 3 or higher treatment-related adverse event, with neutropenia the most common at 26% grade 3 or higher.¹

CEO Anand Parikh said the firm believes the data support what it calls a "multi-nodal PAM targeting hypothesis" and the company now plans to advance toward a Phase 3 trial, subject to regulatory alignment.¹

This builds on Faeth's November 3, 2026 third-quarter update, in which it said topline data from PIK-201 were anticipated by year-end 2026² and disclosed FDA Fast Track designation for PIKTOR plus paclitaxel in biomarker-selected advanced endometrial cancer². The company separately reported a Phase 1b/2 breast cancer trial, FTH-PIK-101, with interim data anticipated in 2027², and said cash, cash equivalents and marketable securities were $174.8 million as of September 30, 2026².