Increased risk of cutaneous immune-related adverse events in patients treated with talimogene laherparepvec and immune checkpoint inhibitors: A multi-hospital cohort study

Background: Previous studies have shown that combining immune checkpoint inhibitors (ICIs) with talimogene laherparepvec (TVEC) may improve antitumor responses. However, the risk of developing cutaneous immune-related adverse events (cirAEs) in patients treated with ICI and TVEC has not been studied.

Objective: To evaluate the differences in cirAE development between patients treated with ICI alone and both ICI and TVEC (ICI + TVEC).

Methods: Patients with cutaneous malignancy receiving ICI with or without TVEC therapy at the Massachusetts General Brigham healthcare system were included. CirAE development, time from ICI initiation to cirAE, cirAE grade, cirAE morphology, and survival were analyzed. Pearson's χ² test or Fisher's exact test for categorical variables and t test or Kruskal-Wallis test for continuous variables were used. To account for immortal time bias, we performed adjusted time-varying Cox proportional hazards modeling.

Results: The rate of cirAE development was 32.3% and 38.7% for ICI only and ICI + TVEC, respectively. After adjusting for covariates, ICI + TVEC was associated with a 2-fold increased risk of cirAE development (hazard ratio: 2.03, P = .006) compared to patients receiving ICI therapy alone.

Limitations: The retrospective nature and limited sample size from a tertiary-level academic center.

Conclusion: These findings underscore potential opportunities for dermatologists and oncologists in counseling and monitoring patients.