Lumakras + Vectibix showed encouraging efficacy and safety in patients with KRAS G12C-mutated colorectal cancer.

These new data show that combining Lumakras (sotorasib) with Vectibix (panitumumab), Amgen's monoclonal antibody epidermal growth factor receptor (EGFR) inhibitor, demonstrated encouraging efficacy and safety.

Overall, the objective response rate (ORR) was 27% (confirmed and unconfirmed) among 26 patients in the efficacy analysis set (which included 5 patients who had progressed with prior sotorasib monotherapy). The disease control rate (DCR) was 81%. ORR and DCR were secondary endpoints. In the expansion cohort of sotorasib-naïve patients with refractory CRC (n=18), 33% of patients experienced a response (confirmed and unconfirmed). These data are being featured during the European Society of Medical Oncology 2021 (ESMO21) Virtual Congress.

"We are excited by these CodeBreaK 101 data, which show encouraging response rates that were much higher than the 9.7% response rate observed with Lumakras monotherapy and highlight the importance of combination therapy for patients with KRAS G12C-mutated advanced colorectal cancer," said David M. Reese, M.D., executive vice president of Research and Development at Amgen. "Based on these results and the urgent need for new therapies, we are pleased to announce the initiation of a new Phase III trial with Lumakras plus Vectibix in the third-line setting. This new trial, along with our doublet and triplet combination trials in colorectal cancer, demonstrates our commitment to delivering a new treatment option for metastatic CRC patients who harbor the KRAS G12C mutation."

In total, 31 patients with heavily pretreated (median of two prior lines of therapy; range 1-10) KRAS G12C-mutated metastatic CRC were enrolled in the dose exploration and dose expansion cohorts for the combination of Lumakras and Vectibix. No patients experienced dose-limiting toxicities during the 28 days following initial treatment. The majority of treatment-related adverse events (TRAEs) were Grade 1-2 in severity, and no Grade 4 or fatal TRAEs were observed. The most common TRAEs (occurring in greater than 10% of patients) were consistent with known adverse events for Lumakras and Vectibix and included dermatitis acneiform, dry skin, nausea, diarrhea, hypokalemia, hypomagnesemia, pruritus and rash. No new safety concerns were identified.