Treatment with selinexor and low-dose dexamethasone can provide a “meaningful clinical benefit” in patients with penta-refractory multiple myeloma, according to the principal investigator of the STORM trial.
Updated results from this phase 2 trial showed that selinexor and low-dose dexamethasone produced an overall response rate of 26.2% and a clinical benefit rate of 39.3%. The median progression-free survival was 3.7 months and the median overall survival was 8.6 months.
“The additional phase 2b clinical results… are very encouraging for the patients suffering from penta-refractory multiple myeloma and their families,” Dr. Jagannath said in a statement. “Of particular significance, for the nearly 40% of patients who had a minimal response or better, the median survival was 15.6 months, which provided the opportunity for a meaningful clinical benefit for patients on the STORM [Selinexor Treatment of Refractory Myeloma] study.”
STORM (NCT02336815) included 122 patients with penta-refractory multiple myeloma. They had previously received bortezomib, carfilzomib, lenalidomide, pomalidomide, daratumumab, alkylating agents, and glucocorticoids. Their disease was refractory to glucocorticoids, at least one proteasome inhibitor, at least one immunomodulatory drug, daratumumab, and their most recent therapy.
The patients had received a median of seven prior treatment regimens. Their median age was 65 years, a little more than half were men, and more than half had high-risk cytogenetics. Patients received oral selinexor at 80 mg twice weekly plus dexamethasone at 20 mg twice weekly until disease progression.Two patients (1.6%) achieved stringent complete responses. They also had minimal residual disease negativity, one at the level of 1 x 10–6 and one at 1 x 10–4.
Very good partial responses were seen in 4.9% of patients, 19.7% had partial responses, 13.1% had minimal responses (MRs), and 39.3% had stable disease. Progressive disease occurred in 13.1% of patients; 8.2% were not evaluable for response.