Karyopharm has seen studies for its big hope selinexor placed on a partial clinical hold, meaning it can no longer recruit new patients, over the FDA’s demands for more safety details, but the company insists this is all down to paperwork errors.
The company has announced that FDA won’t allow further enrollment, telling the biotech 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 said in a statement has made the changes, and sent on the amended docs to the FDA, and was keen to stress that the hold had nothing hold with patient deaths, or “new information regarding the safety profile of selinexor,” which has been tested on nearly 2,000 patients to date.
It has however been hit with safety concerns before, and back in August 2015 the company saw a spike in dangerous infections that have it to alter the dosing in the drug's phase 2 study in older patients with acute myeloid leukemia.
“Karyopharm believes that its previously disclosed enrollment rates and timelines for its ongoing trials will remain materially unchanged,” it said, adding that those with stable disease will continue being treated in its studies.
Analysts at Leerink tended to agree, saying that its management told the firm the issues was “due to an administrative error,” rather than new safety concerns.
Leerink said that phase 2 results in diffuse large B-cell lymphoma (DLBCL) and liposarcoma “represent additional, potential shots on goal for selinexor this year, but multiple myeloma is the main value driver longer term in our view.”
“We're cautiously optimistic regarding the opportunity for selinexor in diffuse large B-cell lymphoma (DLBCL),” the firm said, “but note that the SADAL trial may potentially take a bit longer to complete than originally anticipated.”
Meanwhile, interim data from the liposarcoma phase 2/3 trial of selinexor compared to placebo in relapsed/refractory patients are expected by mid-year in the first 50 randomized patients.
“Ultimately, we see selinexor's most likely path to market in multiple myeloma, based on results presented to date indicating around a 20% response-rate in penta-refractory patients, but we think it'll take at least until mid-2018 until potential pivotal data will be available,” the firm said.
This comes just a week after the biotech said a phase 2 trial of selinexor, in patients with acute myeloid leukemia (AML), was deemed destined to fail during an interim analysis.
The failure wiped 15% of Karyopharm’s stock price when it looked likely that the selinexor cohort of the midstage test would not achieve a statistically-significant improvement in overall survival.