Navlimetostat

Tango Therapeutics reported data for its experimental pancreatic cancer drug that are strong enough for the company to move it into a Phase 3 study while concurrently raising $225 million to get things going. In a study of pancreatic cancer patients with a common mutation called MTAP deletion, Tango said Thursday that vopimetostat (formerly TNG462) achieved a 25% objective response rate in 39 patients with at least six months of follow-up. These patients, who had received one prior therapy, had a median progression-free survival of 7.2 months. Pancreatic cancer is one of the most difficult kinds of cancers to treat, and prognoses are poor. Though a 25% response rate would not move the needle much in other tumor types, Tango said it represents more than double the rate seen in historical controls. Tango estimates about 35% of all pancreatic cancer patients have the MTAP deletion mutation. Tango now plans to start a global Phase 3 study for the PRMT5 inhibitor in second-line pancreatic cancer with MTAP deletion in 2026, but it will have to discuss the results with the FDA later this year. The study will aim to enroll about 300 patients and compare vopimetostat to standard chemotherapy regimens. Tango raised $225 million along with the data, netting $210 million from an underwritten offering and $15 million from a PIPE financing. Tango’s shares $TNGX rose about 25% in premarket trading, but fell roughly 15% after Thursday’s opening bell. Analysts expect Tango’s vopimetostat to compete with programs from Bristol Myers Squibb, which is also researching a PRMT5 inhibitor, and Ideaya Biosciences, which is developing a MAT2A inhibitor. During Tango’s call on Thursday morning, one analyst noted that patients responded to vopimetostat in a median of 3.5 months, compared to five months for Bristol Myers’ BMS-986504, which is in multiple mid- and late-stage studies. In response, Tango CEO Barbara Weber said it’s difficult to know what’s driving that difference. “We do believe that vopimetostat has substantively better target coverage at 250 mg than BMS-986504 does at 400 or 600 mg,” Weber said. “So it’s possible that is partly what’s driving it. It’s hard to say for sure.” The pancreatic cancer cohort only represented some of Tango’s data. The company also set up a study group in lung cancer and for another cohort of patients who have a variety of tumors but all have MTAP deletions. In total, 179 patients received the drug, 94 of whom were evaluable for efficacy with at least six months of follow-up. The ORR among the 94 patients was 27%, with a median PFS of 6.4 months. The lung cancer data were not yet mature, but about 15% of all lung cancer patients have the MTAP deletion mutation, Tango said. In the third group, which Tango referred to as “histology agnostic,” 49% of 41 patients saw a response after six months. Median PFS was 9.1 months. There were 13 different kinds of cancer observed in the group, including mesothelioma, esophageal and head and neck. The analysis of the 41 patients did not include nine sarcoma patients, none of whom responded to the drug. There were no life-threatening side effects or deaths caused by the drug in the study. Severe side effects were “rare,” Tango said, except for severe anemia, which occurred in 13% of all patients.