Lilly experimental combination posts 79.3% response rate in platinum-sensitive ovarian cancer
Key Facts
Eli Lilly said its experimental drug combination of sofetabart mipitecan and bevacizumab achieved a confirmed objective response rate of 79.3% in 29 patients with platinum-sensitive ovarian cancer, in Phase 1 data presented by the company at the ESMO 2026 conference. The group included 33 women who received the combination, at doses of 4 mg/kg of sofetabart mipitecan and 15 mg/kg of bevacizumab. The result does not apply to the drug alone, and sofetabart mipitecan remains under study. The study recorded 23 confirmed responses among the 29 patients with measurable disease. Lilly said the disease control rate was 100% in the group.
The confirmed responses comprised 6 complete responses, representing 20.7% of patients with measurable disease, and 17 partial responses, representing 58.6%. The response rate was 79% or higher among patients who had previously received PARP inhibitors and among those who had not, according to the company. Lilly said activity was observed across different FRα expression levels and regardless of prior exposure to these inhibitors. The median number of previous systemic treatments was three, within a range of one to six. Some 67% of participants had previously received a PARP inhibitor, while 70% had received bevacizumab before the study.
But estimates of response durability and disease control were immature at the data cutoff on 6 July 2026. Median duration of response was not estimated at a median follow-up of 6.2 months, and median progression-free survival was not estimated at a median follow-up of 10.2 months. These measures provide a picture of the available follow-up period, while the duration of response and progression-free survival remain undetermined in this readout. The company said about 70% of ovarian cancer patients will experience a recurrence after an initial response to platinum-based chemotherapy. This context places the development of new options for platinum-sensitive disease at the center of Lilly's program, without turning Phase 1 results into evidence of confirmed clinical benefit.
On safety, nosebleeds and nausea were the most common treatment-emergent adverse events, at 73% each. The company reported anemia in 58% of patients, neutropenia in 55% and fatigue in 52%. The most common Grade 3 or higher events were neutropenia at 42% and anemia at 24%; febrile neutropenia also occurred in 3%. Neuropathy of any grade was observed in 9%, with no cases of Grade 3 or higher. Lilly also reported dose reductions in 42% of patients.
Jacob Van Naarden, head of Lilly Oncology, said the standard of care for platinum-sensitive ovarian cancer "has not changed in a decade and requires new treatment options." The company added that the results support continued evaluation of the drug in Phase 3, but the combination is not approved to treat the disease. The FRAmework-01 program is testing the drug in three global Phase 3 parts covering different groups of platinum-sensitive and platinum-resistant ovarian cancer. In platinum-resistant disease, sofetabart mipitecan is being tested alone, while it is being tested with bevacizumab in two groups with platinum-sensitive disease. The latter two groups differ according to whether patients had previously received a PARP inhibitor.
Lilly's scientific program at the ESMO 2026 conference listed a poster on the combination's efficacy and safety in platinum-sensitive ovarian cancer dated 23 October 2026, and a presentation on sofetabart mipitecan dated 24 October. In market trading, LLY shares closed at $1,273.46 on 23 October, compared with a close of $1,306.69 in the previous session. This change does not establish that the trial results caused the stock movement. Sofetabart mipitecan targets the FRα receptor and is an experimental drug comprising an antibody linked to an exatecan payload, according to the company. Lilly says FRα is present in most ovarian cancers at levels far higher than in healthy tissue.