Karyopharm Therapeutics has announced that their lead drug, selinexor (KPT-330), has been granted Fast Track designation by the US Food and Drug Administration (FDA), for the treatment of multiple myeloma (MM) patients that have received at least three prior lines of therapy. Such MM patients now eligible for selinexor must have received, and be refractory to, regimens containing at least one of each of the following: an alkylating agent, a glucocorticoid, an immunomodulatory drug, a proteasome inhibitor, and daratumumab.
This decision is based on the early success of the ongoing Phase IIb STORM study, in which penta-refractory patients have been treated with 80 mg of selinexor twice weekly, plus 20 mg of low-dose dexamethasone. The precursor phase I trial is detailed here. Such Fast Track designation speeds up the FDA process of approval and is reserved for serious health conditions that lack treatment options. This decision will be welcomed by this population of heavily pre-treated MM patients for whom treatment options are currently lacking.
Selinexor is an orally administered Selective Inhibitor of Nuclear Export (SINE), which binds to the nuclear export protein XPO-1, driving selective apoptosis of the tumor cells. It is currently being tested in a number of phase II trials in different combinations and looks set to be approved for further treatment indications in the near future.