Wang LL, et al. - Researchers assessed the timing of cutaneous drug reactions following initiation of programmed cell death protein 1 (PD-1) inhibitor therapy in this retrospective observational study. The findings suggested that various cutaneous adverse reactions secondary to PD-1 inhibitor use might present with delayed onsets, even after discontinuation of the medication. They advised that skin specialists ought to know about the possibility of delayed cutaneous adverse reactions.

Methods

• Study participants were patients referred to an academic dermatology clinic by an oncologist from January 1, 2014 through February 28, 2018, with at least 1 skin biopsy specimen of a skin reaction associated with PD-1 inhibitor use.
• All participants had a biopsy-proven cutaneous reaction in response to using pembrolizumab, nivolumab, or nivolumab with ipilimumab as immunotherapy for cancer.
• Time to onset of biopsy-proven cutaneous reactions that occurred during or after use of pembrolizumab or nivolumab was the main outcome measure.

Results

• In this analysis, researchers identified 17 subjects (12 men, 5 women; mean [SD] age, 68.6 [11.1] years) who presented with cutaneous adverse reactions related to PD-1 inhibitor therapy; these reactions included bullous pemphigoid, lichenoid dermatitis, erythema multiforme, lupus, eczema and sarcoidosis.
• It was noted that 12 patients presented with reactions at least 3 months after beginning pembrolizumab or nivolumab therapy.
• After drug initiation, it took a median (range) of 4.2 months (0.5-38.0 months) for skin reactions to present.
• Cutaneous adverse reactions attributed to the PD-1 inhibitor therapy developed after the drug therapy was terminated in five cases.