Lenalidomide desensitization for delayed hypersensitivity reactions in 5 patients with multiple myeloma

Lenalidomide, an analogue of thalidomide, is an immunomodulatory agent that is approved for use in multiple myeloma (MM), myelodysplastic syndrome and mantle cell lymphoma. Lenalidomide is administered as a single agent or in conjunction with dexamethasone in relapsed and refractory MM (Richardson et al, 2009), as an induction therapy for newly diagnosed MM (Rajkumar et al, 2010) and as a single agent maintenance therapy following autologous stem cell transplantation (McCarthy et al, 2012). Although generally well tolerated, lenalidomide therapy is frequently associated with rashes, ranging from urticaria, purpura or morbiliform lesions and Stevens–Johnson Syndrome (SJS) or Toxic Epidermal necrolysis (TEN) (Sviggum et al, 2006). A recently published meta-analysis of lenalidomide-associated rash in cancer patients reported an incidence of all-grade and high-grade rash of 27 2% and 3 6% respectively (Nardone et al, 2013). Interestingly, individuals with HLA-DRB1*1501 and HLA-DQB1*0602 could present with more severe dermatological reactions during lenalidomide treatment (Penna et al, 2012). Desensitization remains an option in patients with lenalidomide-associated rash and three case reports of rapid, inpatient desensitization in patients with acute urticarial rash have previously been published (Table I) (Phillips et al, 2007; Ca~ namares Orbis et al, 2012; Seki et al, 2013). We report five MM patients with delayed adverse skin reactions to lenalidomide who were able to tolerate lenalidomide via an outpatient desensitization protocol and without subsequent adverse effects (Table II). None of these patients presented with fever, mucosal involvement, bullous-like lesions, and shortness of breath or syncope.