No abstract

Background: Although clinical practice guidelines for the management of Immune Checkpoint Inhibitor (ICI)-related adverse events have recently been published, precise and nuanced toxicity data for combination ICI therapy are lacking. Therefore, herein we have conducted a systematic review and meta-analysis of published clinical trials on combination ICI to synthesize the treatment-related adverse event (TRAE) profile of combination ICI therapy. Methods: PUBMED, EMBASE, and the Cochrane Database/EBM were searched for eligible studies. Clinical trials evaluating combination immune checkpoint inhibitor therapy in advanced unresectable cancer were included in the analysis based on prespecified criteria. Risk of bias across studies was evaluated using Begg's funnel plot and Egger's regression test. The summary outcomes were pooled risk ratios (RR) and the logit-transformed proportion for incidence data. Results: A total of 18 studies comprising 2,767 patients across 10 cancer types were included in the final analysis. Combination ICI was associated with a slightly higher risk of all-grade adverse events (RR 1.07 [95% CI 1.03-1.11]) and markedly greater risk of grade 3 or higher adverse events (RR 2.21 [95% CI 1.57-3.10]) compared to monotherapy ICI. Subgroup analyses showed significant differences in risk of grade 3 or higher adverse events between treatment types (PD-1 + CTLA-4 and PD-L1 + CTLA-4), among cancer types, and among dosing regimens (N1I3, N3I1, and D20T1). The incidence of allgrade adverse events was 0.905 [95% CI 0.842-0.945], and the ratio of grade 3 or higher events to all-grade adverse events was 0.396 [95% CI 0.315-0.483]. The most common all-grade TRAEs were diarrhea/colitis, fatigue/asthenia, nausea/vomiting, rash, and pruritis. Conclusion: Combination ICI therapy has a significantly different treatment-related adverse event profile compared to monotherapy.

Stevens-Johnson syndrome (SJS) is a life-threating mucocutaneous reaction predominantly induced by drugs. Targeted cancer therapies such as pembrolizumab, which has been approved for the treatment of metastatic malignancy, can cause severe skin toxicities, including SJS. They are rare and inconsistently reported. In this article, we report the case of a 80-year-old woman with metastatic non–small cell lung cancer who had a SJS-like eruption involving oral mucosa after 15 weeks of exposure of pembrolizumab (6 doses) and 7 days after 1 dose of recombinant zoster vaccine. SJS is a rare blistering disorder with high mortality rate and significant morbidity. Causes include drugs, herpes viruses, and immunization. The timing of the eruption soon after the receipt of recombinant zoster vaccine suggests a role of vaccination in our patient, yet patients receiving cancer immunotherapy may develop late-onset skin toxicity. Therefore, we recommend long-term monitoring for mucocutaneous reactions after initiation of pembrolizumab. Further research is needed to characterize the immunological pathogenesis and improve timely recognition and treatment strategies.