Long-term data support pembrolizumab as ‘a standard of care’ in advanced melanoma
Key takeaways:
- More patients who received pembrolizumab than ipilimumab survived at least 10 years.
- A second course of pembrolizumab benefited some patients.
Pembrolizumab significantly extended OS at 10 years compared with ipilimumab for patients with advanced melanoma, according to study results presented at ESMO Congress.
A second course of pembrolizumab (Keytruda, Merck) exhibited anti-tumor activity in some patients, results showed.
“These results confirm that pembrolizumab provides long-term benefit for advanced melanoma, supporting it as a standard of care in this setting,” Caroline Robert, MD, PhD, head of dermatology at Gustave Roussy Cancer Campus and co-director of the melanoma research unit at INSERM 981 Paris-Sud University, and colleagues wrote.
Background and methods
The randomized phase 3 KEYNOTE-006 included 834 patients with unresectable stage III or stage IV melanoma who had received no more than one prior line of treatment, excluding CTLA-4 and PD-1 inhibitors.
Researchers randomly assigned 556 participants to receive 10 mg/kg pembrolizumab every 2 weeks or every 3 weeks for up to 2 years. The other 278 patients received 3 mg/kg ipilimumab (Yervoy, Bristol Myers Squibb) every 3 weeks for four cycles.
Results of KEYNOTE-006 showed pembrolizumab exhibited “superior efficacy” compared with ipilimumab, researchers wrote.
After KEYNOTE-006, patients had the option to transition to the KEYNOTE-587 extension study. Eligible patients could receive a second course of pembrolizumab — for a maximum 1 year — as part of either KEYNOTE-006 or KEYNOTE-587.
After KEYNOTE-006, 211 patients — including 159 who previously received pembrolizumab — transferred into the into KEYNOTE-587.
For patients who transitioned, median time from entry in KEYNOTE-006 to data cut-off in KEYNOTE-587 was 123.7 months (range, 122-127.3).
OS served as the primary endpoint in KEYNOTE-587. Modified PFS served as a secondary endpoint.
Results
Results showed longer median PFS (32.7 months vs. 15.9 months; HR = 0.71; 95% CI, 0.6-0.85) and a higher 10-year OS rate (34% vs. 23.6%) with pembrolizumab than ipilimumab.
Among the 103 patients who completed at least 94 weeks of pembrolizumab, median OS after week 94 had not been reached. The 8-year OS in this group was 80.8%.
The OS benefit with pembrolizumab persisted across subgroups, including those determined to have poor prognostic features.
Researchers reported longer median modified PFS (9.4 months vs. 3.8 months; HR = 0.64; 95% CI, 0.54-0.75) with pembrolizumab.
Among the 16 patients who received a second course of pembrolizumab, median modified PFS from the start of the second course was 51.8 months (95% CI, 11 to not reached), with a 6-year modified PFS rate of 49.2%.
Collapse
Robert C, et al. Abstract LBA44. Presented at: European Society for Medical Oncology Congress; Sept. 13-17, 2024; Barcelona, Spain.