Dr. Cowan on the Future of Selinexor in Multiple Myeloma

Andrew J. Cowan, MD, an assistant professor of medicine at University of Washington School of Medicine, and hematologist/oncologist at Seattle Cancer Care Alliance, discusses the future of selinexor (Xpovio) in multiple myeloma.

In February 2018, the FDA Oncologic Drugs Advisory Committee (ODAC) voted 8 to 5 against the accelerated approval of the new drug application (NDA) for selinexor. The committee decided to delay the decision which would have been based on data from the phase II STORM trial in anticipation of data from the phase III BOSTON trial. Initially, the agent had shown an objective response rate of 26% in heavily pretreated patients, many of whom were refractory, says Cowan.

On July 3 2019, the FDA granted an accelerated approval to selinexor for use in combination with dexamethasone for adult patients with relapsed/refractory multiple myeloma who have received ≥4 prior therapies and whose disease is refractory to ≥2 proteasome inhibitors, ≥2 immunomodulatory agents, and a CD38-targeted monoclonal antibody. Its full approval is contingent on results of the BOSTON trial, which is evaluating the addition of selinexor to bortezomib (Velcade) and low-dose dexamethasone versus bortezomib/low-dose dexamethasone alone in patients with relapsed/refractory disease who have received 1 to 3 prior regimens.

Although the agent appears to have limited activity as a single agent, it has shown signals of activity when used in combination with dexamethasone, explains Cowan. The results of the phase III trial will help to further establish its role in the disease.