Pomalidomide and dexamethasone until progression after first salvage therapy in multiple myeloma

Lenalidomide maintenance in myeloma is well established. Nevertheless, pomalidomide could provide an alternative. Myeloma patients in first relapse, initially treated in the Intergroupe Francophone du Myélome (IFM) 2009 trial, and subsequently in the IFM 2013-01 phase 2 trial, received four cycles of salvage therapy with pomalidomide plus cyclophosphamide plus dexamethasone (PCD) with transplantation plus 2 PCD consolidation or without transplantation but with 5 PCD and for all patients pomalidomide plus dexamethasone maintenance therapy. This consisted of 28-day cycles of pomalidomide 4 mg daily on days 1-21 and dexamethasone 20 mg weekly until progression. The primary endpoint was an improved response to treatment. A total of 75/100 patients reached therapy. The median follow-up time was 73 months. The median duration of treatment was 23.7 months. One third of patients improved their response from the initiation of treatment: 11%, 19% and 4% to a very good partial response, complete response or stringent complete response respectively. The median progression-free survival time was 33.2 months and the median overall survival time was not reached. Among the 75 patients, the reasons for pomalidomide discontinuation were progressive disease (54%), adverse events (AEs) (30%), investigator discretion (11%) and consent withdrawal (5%). Grade (G) 3/4 haematological AEs included neutropenia (51%) and lymphopenia (35%); G3/4 drug-related non-haematological AEs (>5%) comprised 13% infections. Long-term administration of pomalidomide and dexamethasone is feasible and one third of the patients improved their response.