Evaxion Biotech reports 75% ORR rate in Phase 2 trial of EVX-01

Evaxion announces new two-year unprecedented clinical efficacy data of its personalized cancer vaccine EVX-01 in patients with advanced melanoma. The two-year phase 2 data demonstrates an Objective Response Rate of 75% as 12 out of 16 patients had objective clinical responses, with four patients obtaining a complete response. The ORR is even higher than the 69% observed after one year of treatment. Additionally, a durable clinical benefit was observed as 92% of patients were still responding at 24 months follow-up and no relapses were observed. 54% of patients had a deepened response during treatment, improving from stable disease or partial response to partial or complete response. Tumor reduction was observed in 15 out of the 16 patients enrolled in the trial. EVX-01, developed with Evaxion’s AI-Immunology platform, is designed to target multiple neoantigens; cancer unique proteins arising from mutations. In the trial, EVX-01 induced an immune response in all patients, with 81% of the targeted neoantigens generating potent specific T-cell responses. This high immunogenicity rate stands out as highly encouraging compared to historical observations and compares very favorably to what is seen with other approaches. These results also underline and validate the precision of the AI-Immunology platform in accurately identifying neoantigens, which leads to detectable signals in patients. Data also confirmed EVX-01 to be a well-tolerated treatment. The trial’s primary endpoint, measuring improved responses e.g. patients converting to a better response category, was not formally analyzed due to a reduction in number of enrolled participants compared to the original protocol. However, the 54% conversion rate, would suggest the primary endpoint being met. As the majority of patients were still responding at time of data cut-off, secondary endpoints measuring Progression Free Survival and Overall Survival could not yet be reported.