[Effective BiRd Therapy after the Addition of Clarithromycin for Lenalidomide and Dexamethasone Resistant Multiple Myeloma Ineligible for Stem Cell Transplantation].

BiRd combination therapy, which comprises clarithromycin(CAM: Biaxin®), lenalidomide(LEN: Revlimid®), and dexamethasone( DEX), is a highly effective treatment for newly diagnosed symptomatic multiple myeloma(MM). However, its efficacy against recurrent myeloma refractory to LEN and DEX combination therapy(Rd therapy)remains unclear. In this study, we retrospectively analyzed the data of 7 patients(4 men and 3 women, median age of 76 years)with MM, who had clarithromycin added to their Rd regimen. In all patients, the starting dose of clarithromycin was 400 mg daily and the median number of prior therapies was 3(range, 1-4). Patients received a median of 9 cycles of Rd(range, 6-27 cycles)for a median duration of 8 months. Then, patients received a median of 14 cycles of BiRd(range 2-36 cycles). One patient showed partial response(PR), which was the best response, while the others showed stable disease(SD). Our results demonstrated that the addition of clarithromycin to Rd could overcome resistance to Rd and lead to durable responses, without exacerbating hematological or non-hematological toxicities. Thus, BiRd therapy may represent a therapeutic option for symptomatic MM resist- ant to Rd therapy.