ИСТИНА

Abstract Background: BCD-217-2/OCTAVA (NCT05732805) is an international, multi-center, randomized, double-blind, placebo-controlled phase III study conducted to access the efficacy and safety of prolgolimab+nurulimab (BCD-217) combination therapy with continued prolgolimab therapy compared to prolgolimab monotherapy as 1st line treatment for patients (pts) with unresectable or metastatic melanoma (un/mM). BCD-217 is a fixed-dose combination of nurulimab (aCTLA-4, 5 mg/ml) and prolgolimab (aPD-1, 15 mg/ml) was recently approved as the 1st line treatment for un/mM in Russia. Here we present the primary analysis of the study. Methods: Pts with unresectable or metastatic cutaneous melanoma (IIIC-IVM1a-c) with treatment- naïve for unresectable/metastatic disease were randomized in 2 treatment arms: combination drug containing nurulimab (1 mg/kg) and prolgolimab (3 mg/kg) at a dose of 0.2 ml/kg Q3W during the first four blinded infusions (nuru+prolgo arm) and prolgo arm received prolgolimab monotherapy at a dose of 3 mg/kg Q3W during the first four blinded infusions. Then both arms received prolgolimab maintenance up to two years. The primary endpoint of the study was progression-free survival (PFS). Results: 271 pts were randomized to nuru+prolgo (n=135) or prolgo monotherapy (n=136) arms. After the median of 15.8 mo follow-up the median PFS (mPFS) was 15.4 (10.3; ND) mo in the nuru+prolgo group and 10.8 (4.7; ND) mo in the prolgo monotherapy group (95% CI, HR 0.68 (0.482; 0.957), iRECIST). The mPFS benefit of nuru+prolgo arm compared to prolgo arm are maintained in RECIST 1.1 assessment: 9.9 mo vs 2.8 mo, respectively. ORR and DCR were also higher in NURU+PROLGO arm. mOS was not reached in both groups (95% CI, HR 0,88, (0.50; 1.55)). 12-mos OS was 84% in each arm. Grade 3-4 treatment-related AE were reported in 16.3% of pts in nuru+prolgo arm compared to 14.0% - prolgo arm. Immune-related AEs (irAE) of all grades were reported in 52.6% of cases in nuru+prolgo arm and 32.4% of cases - in prolgo arm (p 0.0007). Majority of them were mild. The proportion of gr.≥3 irAEs was 13.3% vs 5.9% in nuru+prolgo arm and prolgo arm, respectively (p 0.04). Treatment discontinuation due to AE was reported in 9.6% of cases for nuru+prolgo vs 4.4% of cases for prolgo arm. Conclusions: OCTAVA trial resuts demonstrated that the fixed-dose combination of nurulimab + prolgolimab is significantly more effective than aPD-1 monotherapy without a serious deterioration of the safety profile in patients with metastatic or unresectable cutaneous melanoma as 1st line therapy.