Case report: pomalidomide as maintenance after salvage autologous stem cell transplantation in a patient with relapsed multiple myeloma

Abstract

Currently, lenalidomide is the only immunomodulatory drug (IMiD) approved for maintenance therapy in patients with newly diagnosed multiple myeloma who have received high-dose chemotherapy and autologous stem cell transplantation (ASCT). The maintenance with lenalidomide showed an advantage over placebo or observation for both progression-free and overall survival in a series of phase 3 randomized trials. Salvage ASCT can be performed after disease relapse in case of a long-term response after the first transplantation or if this option has not been performed before. Pomalidomide is a third-generation IMiD approved for the treatment of relapsed and refractory multiple myeloma, which is efficient in patients with resistance to lenalidomide and proteasome inhibitors. Structurally, lenalidomide and pomalidomide are similar, and therefore the latter can also be considered as a drug for maintenance, however, there are no relevant phase 3 randomized trials. In this article, we present a clinical case of a 60-year-old patient with newly diagnosed multiple myeloma who progressed after 2 lines of induction therapy, which included lenalidomide and two proteasome inhibitors (bortezomib, ixazomib). The use of Pd combination (pomalidomide, dexamethasone) made it possible to achieve a repeated response and implement of salvage ASCT. The second ASCT was carried out only 12 months later after the first due to the COVID-19 pandemic. Subsequent long-term maintenance therapy with pomalidomide resulted in a complete response and minimal residual disease negativity. The resulting response has persisted at the time of this writing for over 2 years. To discuss the presented clinical case, the data of the French phase 2 IFM 2013-01 study were used, in which patients with failed first-line transplantation in case of relapse received PCd (pomalidomide, cyclophosphamide, dexamethasone) induction, salvage ASCT, and maintenance by Pd until disease progression. Pomalidomide may be an acceptable substitute for lenalidomide in patients with prior intolerance or refractory to this IMiD.