Multiple Myeloma Combination Shows Response in Pretreated Patients

Patients with relapsed and refractory multiple myeloma responded to selinexor combination therapy during a phase 1 trial discussed during the American Society of Clinical Oncology (ASCO) conference.

Selinexor inhibits a protein in the nucleus of cancer cells and activates tumor suppressors that kill off the cancer. It is the first drug in a new class of agents called selective inhibitor of nuclear export compounds. In preclinical studies, selinexor was found synergistic in combination with doxorubicin in multiple myeloma mouse models.

The phase 1 trial goals were to determine the maximum tolerated dose of selinexor, liposomal doxorubicin, and dexamethasone, as well as the recommended dose for phase 2 in patients with relapsed and refractory multiple myeloma who received 2 or more prior therapies, including lenalidomide and a proteasome inhibitor.

The treatment also included a loading and maintenance phase that each consist of selinexor and dexamethasone solely. Upon submission of the abstract, 11 patients with a median of 5 previous therapies were enrolled in the study.

Common adverse events potentially related to treatment included hyponatremia, anemia, thrombocytopenia, neutropenia, diarrhea, vomiting, hyperglycemia, and fatigue. The dose limiting toxicities were nausea, low sodium levels, and low platelet counts.

Out of 10 patients evaluated, 2 achieved a very good partial response, 2 a partial response, and 2 a minimal response. There were 4 patients who had no response.

The preliminary findings suggest that the selinexor combination regimen is active in relapsed and refractory multiple myeloma.