Selinexor Approved by FDA for Refractory or Relapsed Multiple Myeloma
Posted: Tuesday, December 22, 2020
On December 18, the U.S. Food and Drug Administration (FDA) granted approval to the oral nuclear export inhibitor selinexor (Xpovio) in combination with bortezomib and dexamethasone for the treatment of adults with multiple myeloma who had received at least one prior therapy. The recent FDA approval expands the 2019 accelerated approval for selinexor in combination with dexamethasone for the treatment of adults with relapsed or refractory multiple myeloma who received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, at least two immunomodulatory agents, and an anti-CD38 monoclonal antibody.
This FDA approval was based on the results of the open-label, multicenter, active comparator-controlled BOSTON trial. Patients with relapsed or refractory multiple myeloma who had received between one and three prior therapies were recruited for the study. Patients received once-weekly selinexor orally in combination with once-weekly bortezomib subcutaneously and low-dose dexamethasone twice weekly orally compared with the standard twice-weekly bortezomib plus low-dose dexamethasone. The estimated median progression-free survival was 13.9 months with selinexor plus bortezomib and dexamethasone and 9.5 months with bortezomib plus dexamethasone.
The most common adverse reactions reported in at least 20% of patients included nausea, fatigue, decreased appetite, diarrhea, peripheral neuropathy, upper respiratory tract infection, decreased weight, cataract, and vomiting. Grade 3 or 4 laboratory abnormalities in 10% or more of patients included thrombocytopenia, lymphopenia, hypophosphatemia, anemia, hyponatremia, and neutropenia.
The recommended selinexor dose is 100 mg orally once weekly on day 1 of each week of a 35-day cycle until disease progression or unacceptable toxicity in combination with:
- Bortezomib at 1.3 mg/m2 administered subcutaneously once weekly on day 1 of each week for 4 weeks followed by 1 week off
- Dexamethasone at 20 mg taken orally twice weekly on days 1 and 2 of each week.
For full prescribing information, visit accessdata.fda.gov.