Relatlimab and Nivolumab versus Nivolumab in Untreated Advanced Melanoma

BACKGROUND

Lymphocyte-activation gene 3 (LAG-3) and programmed death 1 (PD-1) are distinct inhibitory immune checkpoints that contribute to T-cell exhaustion. The combination of relatlimab, a LAG-3-blocking antibody, and nivolumab, a PD-1-blocking antibody, has been shown to be safe and to have antitumor activity in patients with previously treated melanoma, but the safety and activity in patients with previously untreated melanoma need investigation.

METHODS

In this phase 2-3, global, double-blind, randomized trial, we evaluated relatlimab and nivolumab as a fixed-dose combination as compared with nivolumab alone when administered intravenously every 4 weeks to patients with previously untreated metastatic or unresectable melanoma. The primary end point was progression-free survival as assessed by blinded independent central review.

RESULTS

The median progression-free survival was 10.1 months (95% confidence interval [CI], 6.4 to 15.7) with relatlimab-nivolumab as compared with 4.6 months (95% CI, 3.4 to 5.6) with nivolumab (hazard ratio for progression or death, 0.75 [95% CI, 0.62 to 0.92]; P = 0.006 by the log-rank test). Progression-free survival at 12 months was 47.7% (95% CI, 41.8 to 53.2) with relatlimab-nivolumab as compared with 36.0% (95% CI, 30.5 to 41.6) with nivolumab. Progression-free survival across key subgroups favored relatlimab-nivolumab over nivolumab. Grade 3 or 4 treatment-related adverse events occurred in 18.9% of patients in the relatlimab-nivolumab group and in 9.7% of patients in the nivolumab group.

CONCLUSIONS

The inhibition of two immune checkpoints, LAG-3 and PD-1, provided a greater benefit with regard to progression-free survival than inhibition of PD-1 alone in patients with previously untreated metastatic or unresectable melanoma. Relatlimab and nivolumab in combination showed no new safety signals. (Funded by Bristol Myers Squibb; RELATIVITY-047 ClinicalTrials.gov number, NCT03470922.).

Relatlimab (RELA) plus nivolumab (NIVO) versus NIVO in first-line advanced melanoma: Primary phase III results from RELATIVITY-047 (CA224-047)

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Background: Immune checkpoint inhibitor therapy has revolutionized the treatment of patients with advanced melanoma. However, novel combinations are needed to optimize the benefit-risk profile. Lymphocyte-activation gene 3 (LAG-3) regulates an immune checkpoint pathway, which inhibits T-cell activity, and is upregulated in many tumor types including melanoma. Relatlimab (RELA), a human IgG4 LAG-3-blocking antibody, restores effector function of exhausted T cells. RELA in combination with nivolumab (NIVO; anti-programmed death [PD]-1) modulates potentially synergistic immune checkpoint pathways and can enhance antitumor immune responses. RELATIVITY-047 is a global, randomized, double-blind, phase II/III study evaluating a novel immune checkpoint inhibitor combination of RELA+NIVO as a fixed-dose combination (FDC) treatment in first-line advanced melanoma. Methods: Patients with previously untreated advanced melanoma were randomized 1:1 to receive RELA 160 mg + NIVO 480 mg FDC intravenously (IV) every 4 weeks (Q4W) or NIVO monotherapy 480 mg IV Q4W, stratified by LAG-3 expression, programmed death ligand 1 expression, BRAF mutation status, and AJCC (v8) M stage. The primary endpoint was progression-free survival (PFS) per RECIST v1.1 as assessed by blinded independent central review. Secondary endpoints were overall survival and objective response rate. PFS in prespecified subgroups and safety were additional objectives. Results: 714 patients were randomized to RELA+NIVO FDC (n = 355) or NIVO (n = 359). Patient characteristics were well balanced between treatment groups. Median follow-up was 13.2 months. Median PFS in the RELA+NIVO FDC group (10.1 months [95% CI, 6.4–15.7]) was significantly longer than in the NIVO group (4.6 months [95% CI, 3.4–5.6]; hazard ratio, 0.75 [95% CI, 0.6–0.9]; P = 0.0055). PFS rates at 12 months were 47.7% (95% CI, 41.8–53.2) and 36.0% (95% CI, 30.5–41.6) for RELA+NIVO FDC and NIVO, respectively. PFS favored RELA+NIVO FDC across key prespecified subgroups. The incidence of grade 3/4 treatment-related adverse events (TRAEs) was higher in the RELA+NIVO FDC group (18.9%) versus NIVO (9.7%). There were 3 treatment-related deaths with RELA+NIVO FDC and 2 with NIVO. TRAEs (any grade) led to treatment discontinuation in 14.6% and 6.7% of patients in the RELA+NIVO FDC and NIVO groups, respectively. Conclusions: First-line treatment with RELA+NIVO FDC demonstrated a statistically significant PFS benefit compared to NIVO monotherapy in patients with advanced melanoma. RELA+NIVO FDC was well tolerated with a manageable safety profile and without unexpected safety signals. This is the first phase III study of a novel FDC to demonstrate a clinically meaningful benefit by dual inhibition of the LAG-3 and PD-1 pathways. Clinical trial information: NCT03470922.