Safety and efficacy of anti-PD-1 antibodies in elderly patients with metastatic melanoma

Abstract

Background: The incidence of melanoma increases with age. Anti‐PD‐1 antibodies are often the first option for elderly patients with metastatic melanoma, particularly given the low rate of BRAF mutations in this group, however there are limited data regarding their safety and efficacy. Methods: All patients treated with anti‐PD‐1/L1 antibodies on clinical trials at 4 centres were retrospectively identified. Patient demographics, primary and metastatic melanoma characteristics, toxicity, response and survival data were collected. Statistical comparisons were made between older (>75 yrs) and younger (<75 yrs) patients. Results: 283 patients were included in the analysis, median follow‐up of 44.5 months. 208 had pembrolizumab and 71 had nivolumab. Median age was 62 (range 22‐87). The cohort had typical prognostic features (75% AJCC stage M1c, 57% ECOG PS 0, 40% elevated LDH, 14% treated stable brain metastases). 124 (43%) had prior ipilimumab, and 63 (22%) prior MAPK inhibitors. 35 (12%) pts were >75 yrs old, and they had similar prognostic features as those <75yrs, similar rates of prior ipilimumab, but less prior MAPK inhibitors (2/35 [6%] vs 61/256 [24%], P = 0.04). The objective response rate in pts >75 was similar to pts <75 (17/35 [48%] and 89/256 [34%], respectively. There was no difference in the incidence of immune‐related adverse events in those >75 than those <75 (14/35, [40%] and 95/256, [37%], p > 0.05), and the rates of discontinuation for toxicity were similar (0.05% and 0.05%, p > 0.05). Median PFS and OS was similar in older (8.7 months and 33.5 months) and younger (4.6months and 48.1m onths) patients (P = 0.48). Updated analysis including efficacy associations with primary melanoma features and blood parameters at baseline and early during treatment across the whole cohort will be presented. Conclusions: Anti‐PD‐1 antibodies are safe and effective in elderly patients, with response and toxicity profiles similar to that observed in younger patients.