Metastatic melanoma patient outcomes since introduction of immune checkpoint inhibitors in England between 2014 and 2018.

Abstract

55 Background: Population-based research provides real world information about prescribing trends, as well as benefits and harms associated with new interventions first evaluated in randomized clinical trials (RCTs). The national health service in England has comprehensive databases which we used to track prescribing of checkpoint inhibitors (CPIs) approved for 1st line use in metastatic melanoma and determine patient outcomes associated with survival and treatment toxicity. Methods: National Cancer Registration and Analysis Services (NCRAS) datasets were used to identify metastatic melanoma patients (pts) prescribed 1st line CPIs and calculate survival outcomes. The HES (Hospital Episode Statistics) database was used to identify emergency attendances and emergency hospital admissions. Results: 5465 melanoma pts were registered between April ‘14 and March ‘18. 2322 pts received 1st line CPIs: 1174 pembrolizumab (pem), 724 ipilimumab (ipi), 52 nivolumab (nivo), 372 ipinivo. Prescribing reflected national access, with ipi starting in July ‘14 and dropping rapidly on approval of pem in Nov ’15. Ipinivo prescriptions increased annually since July ’16. There was good 3yr OS concordance with RCT outcomes for ipinivo (56%), nivo (51%), pembro (40%) and ipi (32%). Pts treated with ipinivo were significantly younger (88% vs 49% <70 years, P<0.001) and fitter (60% vs 38% ECOG PS 0, P<0.0001) than pts treated with antiPD1. 30-day mortality from last SACT was 3.8% for ipinivo, 9.1% for antiPD1 and 9.4% for ipi. 30-day rates of emergency hospital admissions/A&E emergency attendances from the earliest SACT and last SACT treatment dates were significantly higher for ipinivo (37%/16% and 55%/19%) compared with antiPD1 (17%/8% and 29%/14%) and ipi (24%/9% and 40%/15%), P<0.01. 25% of ipinivo-, 4% of antiPD1- and 15% of ipi-treated pts had a hospital admission for colitis. Conclusions: This largest real world dataset demonstrated rapid uptake of CPIs and survival outcomes similar to RCTs. Use of emergency services varied by regimen, with colitis dominating hospitalization after ipi+/-nivo. Pt selection appeared to differ for different regimens, the consequences of which warrant further research.