Karyopharm Announces Completion of Enrollment in the Phase 3 SENTRY Trial in Myelofibrosis
– Top-Line Results Anticipated in March 2026 –
NEWTON, Mass., Sept. 10, 2025 — Karyopharm Therapeutics Inc. (Nasdaq: KPTI), a commercial-stage pharmaceutical company pioneering novel cancer therapies, today announced that it has completed enrollment in the Phase 3 SENTRY trial, which is evaluating selinexor in combination with ruxolitinib in JAK inhibitor–naïve myelofibrosis patients.
“We are excited to announce that we have completed enrollment of our Phase 3 SENTRY trial and look forward to sharing top-line data from this pivotal trial in March 2026,” said Richard Paulson, President and Chief Executive Officer of Karyopharm. “Selinexor plus ruxolitinib has the potential to be the first combination therapy approved for the treatment of myelofibrosis, depending on the outcome of the data. By combining selinexor with the current standard of care, we believe we have the potential to redefine the way people living with myelofibrosis are treated.”
“I am grateful for the patients, their families and caregivers, the investigators and their clinical trial staff, as well as the extraordinary efforts of the Karyopharm team and our external partners for their help in successfully achieving this important milestone,” said Reshma Rangwala, MD, PhD, Chief Medical Officer and Head of Research of Karyopharm. “This trial is advancing our understanding of the treatment of myelofibrosis and the potential role that XPO1 inhibition may play in this disease. People living with myelofibrosis deserve new treatment options and everyone involved in SENTRY is making an important contribution towards our common goal of providing additional options to patients with this disease.”
“We are encouraged by the work that Karyopharm is doing in myelofibrosis and eagerly await data from the Phase 3 SENTRY trial,” said Kapila Viges, Chief Executive Officer of MPN Research Foundation. “The myelofibrosis community is in need of new, more effective therapies that can help a greater number of patients beyond what is available with currently approved options. Efforts to develop new therapies bring hope to the myelofibrosis community and open the potential for patients to have more treatment options. For patients, options matter.”
SENTRY (XPORT-MF-034; NCT04562389) is a Phase 3 clinical trial evaluating a once-weekly dose of 60 mg of selinexor in combination with ruxolitinib compared to placebo plus ruxolitinib in JAK inhibitor–naïve myelofibrosis patients with platelet counts >100 x 109/L. Patients were randomized 2:1 to the selinexor arm. The co-primary endpoints are spleen volume response rate ≥35% (SVR35) at week 24 and the average change in absolute total symptom score (Abs-TSS) over 24 weeks relative to baseline. The Phase 3 trial enrolled 353 patients.
About Myelofibrosis
Myelofibrosis is a rare blood cancer that affects approximately 20,000 patients in the United States and 17,000 patients in the European Union. The disease causes bone marrow fibrosis (scarring), splenomegaly (enlarged spleen), and progressive anemia leading to symptoms such as fatigue and weakness, abdominal discomfort, early satiety, night sweats and bone pain. The only approved class of therapies to treat myelofibrosis are JAK inhibitors, including ruxolitinib. Patients treated with the most commonly prescribed JAK inhibitor often require blood transfusions, and more than 30% will discontinue treatment due to anemia. Anemia and transfusion dependence are strongly correlated with poor prognosis and shortened survival.
References: Clarivate/DRG (2023); Palandri F. et al., Blood Cancer J. 2021; Pardanani A. & Tefferi A., Haematologica 2011.
About XPOVIO® (selinexor)
XPOVIO is a first-in-class, oral exportin 1 (XPO1) inhibitor and the first of Karyopharm’s Selective Inhibitor of Nuclear Export (SINE) compounds for the treatment of cancer. XPOVIO functions by selectively binding to and inhibiting the nuclear export protein XPO1. XPOVIO is approved in the U.S. and marketed by Karyopharm in multiple oncology indications, including:
- In combination with bortezomib and dexamethasone (XVd) in adult patients with multiple myeloma after at least one prior therapy;
- In combination with dexamethasone for heavily pre-treated adult patients with multiple myeloma;
- Under accelerated approval for adult patients with diffuse large B-cell lymphoma (DLBCL) after at least two lines of systemic therapy.
XPOVIO (also known as NEXPOVIO in certain countries) has received regulatory approvals in multiple ex-U.S. territories and countries, including the European Union, the United Kingdom, Mainland China, Taiwan, Hong Kong, Australia, South Korea, Singapore, Israel, and Canada. Selinexor is also being investigated in several other mid- and late-stage clinical trials across multiple high unmet-need cancer indications, including endometrial cancer and myelofibrosis.
Important Safety Information (select)
Warnings and Precautions
- Thrombocytopenia: Monitor platelet counts throughout treatment; manage with dose interruption/reduction and supportive care.
- Neutropenia: Monitor neutrophil counts; manage with interruption/reduction and growth factors as needed.
- Gastrointestinal toxicity: Nausea, vomiting, diarrhea, anorexia and weight loss may occur; provide antiemetic prophylaxis and supportive care.
- Hyponatremia: Monitor serum sodium; correct contributing causes and manage appropriately.
- Serious infection: Monitor for infection and treat promptly.
- Neurological toxicity: Advise patients to refrain from driving or hazardous activities until resolved.
- Embryo–fetal toxicity: Can cause fetal harm; advise use of effective contraception.
- Cataract: May develop or progress; treatment usually requires surgical removal.
Adverse Reactions
The most common adverse reactions (≥20%) observed in clinical studies vary by indication and regimen and include fatigue, nausea, decreased appetite, diarrhea, anemia, thrombocytopenia and weight loss; serious adverse reactions and fatalities have been reported in some studies. See full prescribing information for details.
For additional product information, including full prescribing information, please visit www.XPOVIO.com.
Medical information: Tel: +1 (888) 209-9326; Email: [email protected]
About Karyopharm Therapeutics
Karyopharm Therapeutics Inc. (Nasdaq: KPTI) is a commercial-stage pharmaceutical company focused on novel cancer therapies addressing nuclear export dysregulation. Its lead compound, XPOVIO (selinexor), is approved in multiple oncology indications and the company maintains a focused pipeline in cancers with high unmet need, including multiple myeloma, endometrial cancer, myelofibrosis and DLBCL. For more information visit www.karyopharm.com and follow Karyopharm on LinkedIn and X @Karyopharm.
Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include, without limitation, statements regarding the timing of top-line data from the SENTRY trial, the potential of selinexor to treat various cancers, expectations for clinical development and regulatory submissions, and Karyopharm’s business prospects. These statements are subject to risks and uncertainties that could cause actual results to differ materially. Additional information concerning risks and uncertainties is contained in Karyopharm’s filings with the Securities and Exchange Commission, including under the caption “Risk Factors” in its Quarterly Report on Form 10-Q for the quarter ended June 30, 2025, filed August 11, 2025. Karyopharm disclaims any obligation to update forward-looking statements except as required by law.
XPOVIO® and NEXPOVIO® are registered trademarks of Karyopharm Therapeutics Inc.
SOURCE: Karyopharm Therapeutics Inc.