Eli Lilly reports promising lung cancer drug results

Eli Lilly (LLY) reported encouraging results from clinical trials of its experimental lung cancer drug olomorasib, including a 62% tumor response rate when combined with immunotherapy and chemotherapy. The findings, presented at the European Society for Medical Oncology's 2026 congress in Madrid, support the company's efforts to develop a new initial treatment for patients with a difficult-to-treat form of lung cancer.

Olomorasib targets KRAS G12C, a genetic mutation found in approximately 13% of patients with non-small cell lung cancer, the most common form of lung cancer. The mutation causes a protein involved in regulating cell growth to remain abnormally active, encouraging cancer cells to multiply. Olomorasib is an oral medication designed to block the mutated protein and prevent it from sending growth signals.

In a study involving 77 previously untreated patients, olomorasib combined with Merck's (MRK) Keytruda and chemotherapy produced confirmed tumor shrinkage in 62% of patients. Responses lasted a median of 14.5 months, while patients went a median of 11.6 months before their cancer worsened or they died. This latter measurement, known as progression-free survival, helps researchers assess whether a treatment delays disease advancement.

A separate analysis involving 85 patients evaluated olomorasib alongside Keytruda without chemotherapy. After a median follow-up of 20.7 months, researchers had not yet established the median duration of tumor responses or progression-free survival, suggesting that many patients continued benefiting from treatment. At 18 months, 55% of patients remained alive without their cancer worsening.

For investors, the results strengthen Lilly's (LLY) prospects of entering the market for targeted treatments for KRAS G12C-mutated lung cancer, where no targeted therapies are currently approved for initial treatment. The most important upcoming milestone is the randomized Phase 3 SUNRAY-01 trial, with initial results expected in the first half of 2027. However, the latest findings come from studies without randomized comparison groups, making it premature to conclude that olomorasib improves outcomes over existing treatments.

Lilly's (LLY) ongoing phase 3 program will compare olomorasib combinations against established immunotherapy regimens, with or without chemotherapy. Olomorasib has received FDA Breakthrough Therapy designation for certain lung cancer patients, potentially accelerating its development and regulatory review, but remains unapproved.