AUSTIN, Texas, Feb. 7, 2020 /PRNewswire/ -- Elios Therapeutics, a biopharmaceutical company developing innovative personalized therapeutic cancer vaccines, today announced that the Company presented a subgroup analysis of the prospective, randomized, double-blind, placebo-controlled Phase IIb clinical trial evaluating its personalized tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine, in patients with Stage III and IV resected melanoma.
In the study, 144 participants were randomized to receive either the vaccine or placebo to prevent recurrence. The vaccines were initiated within three months of completion of standard of care therapy at 0, 1, 2, 6, 12, and 18 months. The protocol was amended to allow concurrent treatment with checkpoint inhibitors once approved for the adjuvant setting. The primary endpoint was 24-month disease-free survival (DFS). This pre-specified sub-group analysis examined efficacy by stage, immunotherapy, and checkpoint inhibition. The analysis was performed on the intent-to-treat (ITT) population and per treatment (PT) population, which included all patients who completed the primary TLPLDC or placebo vaccine series at six months.
In the PT analysis, 24-month DFS improved among Stage IV patients in the TLPLDC vaccine group compared to placebo (73.0% vs. 0%; p=0.002) representing a statistically significant and clinically meaningful reduction in the relative risk of disease recurrence for these patients. An improvement was also seen in the ITT analysis (43.0% vs. 0%; p=0.098). Stage IV patients were more likely to receive checkpoint inhibitor therapy (50% vs. 26%, p=0.003). At the 24-month assessment, a difference in DFS between the vaccine and placebo arms was not observed in Stage III patients. Patients with Stage III disease often take longer to experience a recurrence than patients with Stage IV disease, therefore a 36-month assessment of DFS will determine the effect of treatment in this population.