Successful switch to dabrafenib after vemurafenib-induced toxic epidermal necrolysis

Funding sources: none. Conflicts of interest: G.J., S.D. and P.V. have been principal or associate investigators in a Roche‐sponsored trial. G.J., S.D. and P.V. have been principal or associate investigators in a GlaxoSmithKline‐sponsored trial. Dear Editor, Vemurafenib and dabrafenib are selective v‐raf murine sarcoma viral oncogene homolog B (BRAF) inhibitors approved for the treatment of metastatic melanoma harbouring a somatic BRAF V600 mutation.1 2 Cutaneous toxicity, in the form of keratotic hyperproliferative lesions (including squamous cell carcinomas), phototoxicity and maculopapular rash, is the main adverse effect of vemurafenib. Most rashes are moderate and generally manageable with dose reductions.3 However, more serious adverse reactions such as drug reaction with eosinophilia and systemic signs (DRESS) and toxic epidermal necrolysis (TEN) have also been described, although less frequently.4 5 6 7 8 Herein, we report a case of TEN in a patient receiving vemurafenib for metastatic melanoma. After recovery, vemurafenib was successfully substituted with dabrafenib without recurrence.