Overview
Verastem Inc. (NASDAQ: VSTM) saw its shares decline approximately 5% in after‑hours trading on Tuesday following the release of early clinical data for its investigational oral KRAS G12D inhibitor, VS‑7375.
Clinical Trial Results
The company disclosed preliminary findings from the ongoing TARGET‑D 101 Phase 1/2 trial, which evaluates VS‑7375 across multiple dose levels in patients with advanced KRAS G12D‑mutated solid tumours, including metastatic pancreatic ductal carcinoma, metastatic colorectal cancer, and advanced non‑small cell lung cancer.
In the metastatic pancreatic cancer cohort, 93 % of the 14 heavily pre‑treated patients receiving 900 mg once‑daily monotherapy achieved a reduction of more than 50 % in the tumour marker CA19‑9. All 14 evaluable patients remained on treatment at the data cut‑off date.
The safety profile was dominated by low‑grade gastrointestinal adverse events such as nausea, vomiting and diarrhoea, which generally subsided after the first treatment cycle. Only a single Grade 3 nausea event was reported at the 900 mg dose level, and it resolved within four days.
Dose escalation is currently ongoing at 1,200 mg once daily.
Development Programme
Verastem has initiated three Phase 2 registration‑directed studies and aims to complete enrolment across all three trials by the end of 2026.
The company also announced a collaboration with Erasca Inc. to assess VS‑7375 in combination with Erasca’s investigational pan‑RAS molecular glue, ERAS‑0015, in advanced KRAS G12D‑mutant solid tumours.
Verastem plans to meet the U.S. Food and Drug Administration before year‑end to review Phase 3 pivotal trial designs for first‑line metastatic pancreatic cancer, first‑line metastatic colorectal cancer, and first‑line advanced non‑small cell lung cancer. Enrollment in the Phase 3 trials is expected to commence in the first half of 2027.
Market Reaction
The announcement triggered a roughly 5 % decline in Verastem’s share price in after‑hours trading.