Amgen has unveiled new combination study results from an early-stage study evaluating Lumakras (sotorasib) in over ten different investigational combination regimens for the treatment of KRAS G12C-mutated cancers.

One arm of the Phase Ib CodeBreaK 101 study – evaluating Lumakras plus afatinib – enrolled 33 heavily pre-treated patients with KRAS G12C-mutated non-small cell lung cancer (NSCLC).

This included five patient who have previously been treated with Lumakras monotherapy.

Investigators gave ten patients 20 mg of afatinib plus 960 mg of sotorasib, while 23 patients received 30 mg of afatinib and 960 mg of sotorasib.

The data showed an objective response rate (ORR) of 20% in cohort one and 35% in the second cohort, with a disease control rate of 70% and 74% in the two cohorts, respectively.

Meanwhile, another arm tested the combination of Lumakras and trametinib in heavily pre-treated patients with KRAS G12C-mutated solid tumours, including those who had previously received KRAS G12C inhibitor treatment.

In total, 41 patients were enrolled into this group, with 18 patients with NSCLC, 18 patients with colorectal cancer (CRC) and five patients with other solid tumours.

Among patients with CRC who were naïve to KRAS G12C inhibitor treatment, 9% achieved partial response and 82% achieved disease control. Meanwhile, 14% of previously treated CRC patients achieved partial response and 86% achieved disease control.

In the NSCLC population, 20% of KRAS G12C inhibitor naïve patients achieved a partial response and 87% achieved disease control. In patients who were previously treated with a KRAS G12C inhibitor, 67% achieved disease control.

“Amgen will take these afatinib and trametinib results into account as we prioritise which combinations to move forward within our comprehensive Lumakras development programme. We look forward to presenting additional data, including PD-1 and SHP2 combination datasets, in the coming months,” said David M. Reese, executive vice president of Research and Development at Amgen.