The US Food and Drug Administration (FDA) has placed a partial clinical hold on all trials of selinexor (KPT-330).
Selinexor is an inhibitor being evaluated in multiple trials of patients with relapsed and/or refractory hematologic and solid tumor malignancies.
While the partial clinical hold remains in effect, patients with stable disease or better may remain on selinexor.
However, no new patients may be enrolled in selinexor trials until the hold is lifted.
The FDA has indicated that the partial clinical hold is due to incomplete information in the existing version of the investigator’s brochure, including an incomplete list of serious adverse events associated with selinexor.
Karyopharm Therapeutics Inc., the company developing selinexor, said it has amended the brochure, updated the informed consent documents accordingly, and submitted the documents to the FDA as requested.
As of March 10, Karyopharm had provided all requested materials to the FDA believed to be required to lift the partial clinical hold. By regulation, the FDA has 30 days from the receipt of Karyopharm’s submission to notify the company whether the partial clinical hold is lifted.
Karyopharm said it is working with the FDA to seek the release of the hold and resume enrollment in its selinexor trials as expeditiously as possible. The company believes its previously disclosed enrollment rates and timelines for its ongoing trials will remain materially unchanged.
About selinexor
Selinexor is a selective inhibitor of nuclear export (SINE) XPO1 antagonist. The drug binds with and inhibits XPO1, leading to the accumulation of tumor suppressor proteins in the cell nucleus. This reinitiates and amplifies their tumor suppressor function and is believed to induce apoptosis in cancer cells while largely sparing normal cells.
To date, more than 1900 patients have been treated with selinexor. The drug is currently being evaluated in several trials across multiple cancer indications.
One of these is the phase 2 SOPRA trial, in which selinexor is being compared to investigator’s choice of therapy (1 of 3 potential salvage therapies). The trial is enrolling patients 60 years of age or older with relapsed or refractory acute myeloid leukemia who are ineligible for standard intensive chemotherapy and/or transplant.
The SADAL study is a phase 2b trial comparing high and low doses of selinexor in patients with relapsed and/or refractory de novo diffuse large B-cell lymphoma who have no therapeutic options of demonstrated clinical benefit.
STORM is a phase 2b trial evaluating selinexor and low-dose dexamethasone in patients with heavily pretreated multiple myeloma (MM). And STOMP is a phase 1b/2 study evaluating selinexor in combination with existing therapies across the broader population in MM.
Karyopharm is also planning a randomized, phase 3 study known as BOSTON. In this trial, researchers will compare selinexor plus bortezomib and low-dose dexamethasone to bortezomib and low-dose dexamethasone in MM patients who have had 1 to 3 prior lines of therapy.
Additional phase 1, 2, and 3 studies are ongoing or currently planned.