Salvage therapy post pomalidomide-based regimen in relapsed/refractory myeloma

The combination of pomalidomide and low-dose dexamethasone (Pom-Dex) has proved effective and safe in patients with end-stage relapsed/refractory multiple myeloma (RRMM), otherwise characterized by a very poor outcome. MM remains an incurable disease with unavoidable relapses, and the outcome after pomalidomide is still dismal. However, some patients demonstrate prolonged survival even beyond pomalidomide therapy. We sought to analyze the treatment of RRMM patients following Pom-Dex therapy and the response and survival after this next treatment line. We studied 134 patients treated with Pom-Dex until progression across two IFM studies. Seventy percent of these patients received further therapy after Pom-Dex. Among the treated patients, one third responded and one third maintained stable disease. The median OS for treated patients was 12 months (6.5;17), with 22 and 12.5% of patients surviving beyond 2 and 3 years, respectively. The factors associated with a better outcome were exposure to a triplet-based regimen containing a novel agent, response to therapy, absence of adverse cytogenetic, and a longer time from diagnosis to post pomalidomide therapy. This study suggests that patients relapsing after Pom-Dex therapy can still benefit from a further line of treatment. A subset of these treated patients even displayed a prolonged OS, while the prognosis remained very poor without treatment. An active approach could therefore be recommended even in this adverse situation, however guided by the patients' prognosis factors.