Karyopharm Stock (KPTI) Crashes After Hours: Here's What's Driving the Move
I'm LongbridgeAI, I can summarize articles.Karyopharm Therapeutics (NASDAQ: KPTI) shares plummeted 68.47% in after-hours trading following the failure of its Phase 3 XPORT-EC-042 trial for endometrial cancer to meet its primary endpoint of progression-free survival. Despite a non-significant trend favoring selinexor, the company announced it will reduce investment in this indication while prioritizing myelofibrosis and multiple myeloma programs. Additionally, Karyopharm plans to submit a supplemental New Drug Application to the FDA in August for accelerated approval of selinexor in combination with ruxolitinib for myelofibrosis.
Karyopharm Therapeutics Inc. (NASDAQ:KPTI) shares plunged 68.47% in Thursday’s after-hours session after the company reported topline results from its Phase 3 XPORT-EC-042 trial in endometrial cancer, which did not meet its primary endpoint of progression-free survival.
The stock closed Thursday’s regular session up 2.19% at $7.01 before plunging 68.47% to $2.21 in after-hours trading.
Karyopharm is a commercial-stage biotechnology company developing cancer therapies, with its lead product XPOVIO approved for multiple myeloma and additional indications under investigation.
Trial Results
Karyopharm said its Phase 3 XPORT-EC-042 study evaluating selinexor as a maintenance therapy for TP53 wild-type advanced or recurrent endometrial cancer failed to achieve its primary endpoint of progression-free survival.
Although the study showed a trend favoring selinexor, patients in the modified intent-to-treat population recorded a median progression-free survival of 12.75 months compared with 7.43 months for placebo. However, the difference was not statistically significant. The company also reported no new safety signals and said the findings will be presented at a future medical meeting.
Karyopharm said the results do not affect its ongoing selinexor programs in other indications. The company added that it will reduce planned investment in endometrial cancer while prioritizing its myelofibrosis and multiple myeloma programs.
Separately, Karyopharm said Thursday it plans to submit a supplemental New Drug Application to the FDA in August seeking accelerated approval of selinexor in combination with ruxolitinib for myelofibrosis and intends to request Priority Review.
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Trading Metrics
Karyopharm has a market capitalization of approximately $158.87 million, with a 52-week high of $10.99 and a 52-week low of $3.65.
Over the past 12 months, KPTI shares have gained approximately 83.99%.
Benzinga Edge Stock Rankings show negative price trends across the short-, medium- and long-term time frames.
Disclaimer: This content was produced with the help of AI tools and was reviewed and published by Benzinga editors.
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