Comparison of three-weekly and six-weekly pembrolizumab United Kingdom prescribing practice for advanced and resected melanoma

Background: Pembrolizumab is approved for the treatment of advanced and re-sected melanoma and was originally licensed as a three-weekly infusion (Q3W). In April 2019, a six-weekly infusion schedule (Q6W) was also approved. We retrospectively reviewed pem-brolizumab prescribing for patients with melanoma across multiple United Kingdom (UK) centres to compare the safety and efficacy of Q6W with Q3W in real-world clinical practice.Methods: Case notes for melanoma patients treated with pembrolizumab between April 2019 and August 2020 at eight UK centres were reviewed. Prespecified baseline characteristics ofthe Q3W and Q6W cohorts were compared, as well as toxicity and efficacy outcomes. Prescribers were surveyed about their prescribing practice.Results: Two hundred seventy-seven patients were included: 116 commenced Q3W and 161 commenced Q6W pembrolizumab. The proportion of Q6W prescriptions varied by the centre (range 32-88%). Patient factors associated with an increased likelihood of receiving Q3W over Q6W were preexisting autoimmune comorbidity (odds ratio [OR] 0.33; 95% confidence in-terval [CI] 0.12-0.82) and treatment for advanced (versus resected) disease (OR 0.54; 95%CI 0.33-0.90). Toxicity outcomes were broadly similar for Q6W and Q3W: 14.9% versus 15.5% >= grade 3 Common Terminology Criteria for Adverse Events. Estimated 12-month recur-rence-free survival for adjuvantly treated patients was 78.9% for Q6W and 74.2% for Q3W (hazard ratio [HR] 0.93; 95%CI 0.50-1.73). Estimated 12-month progression-free survival for advanced patients was 41.8% for Q6W and 55.9% for Q3W (HR 1.21, 95%CI 0.67-2.18).Conclusions: Q6W is an appropriate option for administering pembrolizumab, given the opportunity to reduce the health service resource burden.Crown Copyright (c) 2023 Published by Elsevier Ltd. All rights reserved.

Automated summary

This study retrospectively reviewed the prescribing of pembrolizumab for melanoma patients in multiple UK centers. The study found that the toxicity outcomes and efficacy were similar between Q6W and Q3W. Preexisting autoimmune comorbidity and treatment for advanced disease were factors associated with a higher likelihood of receiving Q3W.