First-line atezolizumab monotherapy in patients with advanced BRAF^V600 wild-type melanoma

Area of Science:

• Oncology
• Immunotherapy
• Melanoma Research

Background:

• Anti-programmed death-1 (PD-1) agents are standard for advanced melanoma.
• Atezolizumab, an anti-programmed death-ligand 1 (PD-L1) antibody, has shown efficacy in various solid tumors but lacked prior evaluation in melanoma.
• BRAF^V600 wild-type status is a key factor in advanced melanoma treatment selection.

Purpose of the Study:

• To evaluate the safety and efficacy of first-line atezolizumab monotherapy in patients with advanced or metastatic BRAF^V600 wild-type melanoma.
• To determine the objective response rate (ORR) and disease control rate (DCR) as co-primary endpoints.
• To assess progression-free survival (PFS) and adverse events associated with atezolizumab treatment.

Main Methods:

• Phase 1b study cohort (NCT03178851; cohort C) enrolled 52 adults with BRAF^V600 wild-type advanced/metastatic melanoma.
• Patients received atezolizumab 1,200 mg intravenously every 3 weeks as first-line treatment.
• Co-primary endpoints included confirmed ORR and DCR at 16 weeks, assessed by investigators using Response Evaluation Criteria in Solid Tumors v1.1.

Main Results:

• Investigator-assessed confirmed ORR was 35% (95% CI, 22%-49%), including 6% complete responses (CR) and 29% partial responses (PR).
• Disease control rate (DCR) was 46%.
• Median progression-free survival (PFS) was 3.7 months (95% CI, 2.1-7.3). Common adverse events included anemia (27%) and headache (19%).

Conclusions:

• First-line atezolizumab monotherapy is a safe and tolerable treatment option for patients with BRAF^V600 wild-type advanced or metastatic melanoma.
• The study demonstrated notable antitumor activity, supporting atezolizumab's potential role in this patient population.
• Further investigation may be warranted to optimize its use in melanoma treatment algorithms.