Karyopharm Therapeutics’ shares plunged after phase 3 results for Xpovio (selinexor) in endometrial cancer failed to meet the progression-free survival primary endpoint. The Newton, Mass.-based company said the Xport-EC-042 readout showed a 5.3-month median PFS improvement over placebo in adults with TP53 wild-type advanced or recurrent disease, but it did not reach statistical significance. The company also highlighted limited financial runway, reporting cash of $91.2 million as of the end of Q1—expected to fund operations through later in Q3. Karyopharm said it is exploring financings and strategic alternatives, while still planning to file an sNDA in August and requesting priority review and accelerated approval for Xpovio plus Jakafi (ruxolitinib, Incyte) in myelofibrosis based on overall survival data from the phase 3 Sentry trial. The readout immediately reframed near-term priorities for the company, shifting attention from endometrial cancer development to potential regulatory leverage in myelofibrosis.