Eli Lilly’s Olomorasib Posts a 62% Response Rate in Lung Cancer Study

Eli Lilly and Company announced Oct. 25 that its investigational drug olomorasib produced confirmed tumor responses in 62% of patients in a first-line lung cancer study, with randomized comparison data expected in the first half of 2027.

The 77 patients had KRAS G12C-mutant non-small cell lung cancer and received olomorasib with pembrolizumab, pemetrexed and platinum chemotherapy. Investigators confirmed responses in 48 patients. Median follow-up was 18.7 months.

Median duration of response was 14.5 months, with a 95% confidence interval from 8.5 months to not estimable. Median progression-free survival, the time patients lived without their cancer worsening, was 11.6 months, with a 95% confidence interval of 9.5 to 21.5 months. PD-L1 expression was below 50% in 74% of this group.

A separate analysis included 85 patients treated with olomorasib and pembrolizumab without chemotherapy. After a median follow-up of 20.7 months, median duration of response and median progression-free survival had not been reached. The 18-month progression-free survival rate was 55% for the group overall and 65% among patients whose tumors had PD-L1 expression of at least 50%. The two groups received different combinations and were not compared directly.

Neither analysis included a randomized control group, so the results do not establish whether olomorasib improves outcomes over current care. Olomorasib, also known as LY3537982, is an investigational oral KRAS G12C inhibitor and is not approved for use. KRAS G12C mutations occur in about 13% of people with non-small cell lung cancer. No targeted therapy is approved for first-line treatment of this subtype; current care uses immunotherapy, with or without chemotherapy.

In the chemotherapy group, grade 3 or higher treatment-related adverse events included neutropenia in 21% of patients, anemia in 17%, increased ALT in 12% and thrombocytopenia in 12%. Treatment-related events led to olomorasib dose reductions for 19.5% of patients and discontinuation of the regimen for 7.8%. No grade 5 treatment-related events were reported.

Lilly’s Phase 3 SUNRAY-01 study compares olomorasib plus chemoimmunotherapy with the same treatment plus placebo. Enrollment in that part of the study is complete, and the first randomized Phase 3 results are expected in the first half of 2027.