Long GV, et al. - Researchers performed this study to determine the safety and potential benefit of nivolumab (anti–programmed cell death receptor 1) monotherapy beyond Response Evaluation Criteria in Solid Tumors (RECIST) v1.1-defined progression. In the current study, a large proportion of selected patients treated with frontline nivolumab who were clinically stable and judged to be eligible for treatment beyond RECIST v1.1–defined progression by the treating investigators derived apparent clinical benefit without compromising safety.

Methods

• Researchers performed pooled, retrospective analysis of data from phase 3 trials of nivolumab in treatment-naive patients with advanced melanoma (CheckMate 066 or CheckMate 067) conducted at academic and clinical cancer centers.
• For this study, participants were patients treated beyond first disease progression, defined as those who received their last dose of nivolumab more than 6 weeks after progression (TBP group); and patients not treated beyond progression, who discontinued nivolumab therapy before or at progression (non-TBP group).
• They performed data analyses from November 6, 2015, to January 11, 2017.
• They administered nivolumab (3 mg/kg every 2 weeks) until progression or unacceptable toxic effects.
• At the investigator’s discretion, patients were treated beyond progression if deriving apparent clinical benefit and tolerating study drug.

Results

• Researchers randomized 526 patients (39% [n = 203] female; median age, 62 years [range, 18-90 years]).
• Out of these, 306 (58%) experienced disease progression, including 85 (28%) TBP patients and 221 (72%) non-TBP patients.
• Researchers noticed that 24 (28%) of the TBP patients had a target lesion reduction of greater than 30% after progression compared with baseline (TBP>30% group).
• Sixty-five (76%) TBP patients and 21 (87%) TBP>30% patients were still alive at the time of this analysis; 27 (32%) and 11 (46%), respectively, continued to receive treatment.
• Median (range) time from progression to last dose of treatment for TBP patients was 4.7 (1.4-25.8) months and for TBP>30% patients was 7.6 (2.4-19.4) months.
• In this study, median (range) time from progression to greater than 30% tumor reduction was 1.4 (0.2-7.0) months.
• The TBP and non-TBP groups were comparable in terms of treatment-related select grade 3 to 4 adverse events(5 [6%] and 9 [4%], respectively).