Immune Checkpoint Inhibitors and Scleroderma: Data from the European Pharmacovigilance Database.

Background: Immune checkpoint inhibitors (ICIs) can be commonly associated with the occurrence of immune-related adverse drug reactions (irADRs), which can involve any tissue and organ. ICI-induced skin toxicities are common irADRs and they can be a consequence of a rheumatologic ADR, such as in the case of scleroderma. A recent literature review reported that scleroderma and scleroderma mimics represent a group of disorders with significant morbidity that have been described during ICIs' use.

Objective and methods: Considering the clinical significance of scleroderma cases, the present study aimed to analyze the occurrence of these events in patients receiving ICIs by describing data from individual case safety reports (ICSRs) retrieved from the European spontaneous reporting system, EudraVigilance (EV).

Results: Until February 2023, 70 ICSRs with at least one ICI as the suspected drug and at least one preferred term (PT) related to scleroderma cases were retrieved from the EV. Pembrolizumab was reported as suspected in 41 ICSRs, nivolumab in 25 ICSRs, ipilimumab in 8 ICSRs and atezolizumab in 3 ICSRs. Patients who experienced scleroderma cases were adults, and no differences were found in terms of sex distribution. Scleroderma cases were mainly classified as serious, while the outcome was mainly reported as favorable. The most reported PTs were scleroderma and morphea.

Conclusions: Considering the seriousness of ICI-induced scleroderma cases and the recent marketing authorization of some ICIs, we believe that further high-quality clinical studies should be conducted on this topic to better estimate the impact of these events in patients with cancer.