Karyopharm Announces European Medicines Agency’s Validation of its Type II Variation Marketing Authorization Application for NEXPOVIO® (selinexor) in Combination with Velcade® (bortezomib) and Dexamethasone for the Treatment of Adult Patients with Multiple Myeloma

NEWTON, Mass. – Karyopharm Therapeutics Inc. (Nasdaq: KPTI), a commercial-stage pharmaceutical company pioneering novel cancer therapies, today announced that the European Medicines Agency (EMA) has validated the Company’s Type II Variation Marketing Authorization Application (MAA), which seeks to expand the currently authorized indication for NEXPOVIO® in the European Union to include, in combination with Velcade® (bortezomib) and low-dose dexamethasone, the treatment of adult patients with multiple myeloma who have received at least one prior therapy. Validation of the application confirms the submission is complete to begin the EMA’s review process. The MAA is supported by the positive results from the pivotal Phase 3 BOSTON study, which evaluated once-weekly selinexor in combination with once-weekly Velcade® and low-dose dexamethasone (SVd) compared to standard twice-weekly Velcade® plus low-dose dexamethasone (Vd) in patients with multiple myeloma who have received one to three prior lines of therapy. The results of the BOSTON study were published in The Lancet in November 2020 and were the basis for the U.S. Food and Drug Administration approval of XPOVIO’s expanded indication in December 2020.

“The submission of a Type II Variation Marketing Authorization Application based on positive data from the Phase 3 BOSTON study represents an important step towards our goal of further expanding the treatment options available to patients with multiple myeloma in Europe,” said Sharon Shacham, PhD, MBA, President and Chief Scientific Officer of Karyopharm. “We look forward to the EMA’s review of this supplemental data, which further reinforces the broader therapeutic potential of NEXPOVIO.”

In March 2021, NEXPOVIO was granted conditional marketing authorization by the European Commission in combination with dexamethasone for the treatment of multiple myeloma in adult patients who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, two immunomodulatory agents, and an anti-CD38 monoclonal antibody, and who have demonstrated disease progression on the last therapy. The new MAA will be reviewed by Committee for Medicinal Products for Human Use (CHMP), which will issue an opinion to the European Commission regarding the potential approval for the expanded indication. Karyopharm expects this review to be completed in the fourth quarter of 2021. This application is also intended to fulfill Karyopharm’s obligation in the context of the conditional marketing authorization of NEXPOVIO granted in March 2021.

About Multiple Myeloma in Europe

Multiple myeloma (MM) is an incurable cancer with significant morbidity and the second most common hematologic malignancy. In 2020, there were approximately 51,000 new cases and 32,000 deaths from MM in Europe¹. While the treatment of MM has improved over the last 20 years, and overall survival has increased considerably, the disease remains incurable, and nearly all adult patients will eventually relapse and develop disease that is refractory to all authorized anti-MM therapies. Therefore, there continues to be a high unmet medical need for new therapies, particularly those with novel mechanisms of action.

About NEXPOVIO (selinexor)

NEXPOVIO, which is marketed as XPOVIO® in the U.S., is a first-in-class, oral Selective Inhibitor of Nuclear Export (SINE) medicine. NEXPOVIO functions by selectively binding to and inhibiting the nuclear export protein exportin 1 (XPO1, also called CRM1). NEXPOVIO blocks the nuclear export of tumor suppressor, growth regulatory and anti-inflammatory proteins, leading to accumulation of these proteins in the nucleus and enhancing their anti-cancer activity in the cell. The forced nuclear retention of these proteins can counteract a multitude of the oncogenic pathways that, unchecked, allow cancer cells with severe DNA damage to continue to grow and divide in an unrestrained fashion. NEXPOVIO (selinexor) has been granted conditional marketing authorization by the European Commission in combination with dexamethasone for the treatment of multiple myeloma in adult patients who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, two immunomodulatory agents, and an anti-CD38 monoclonal antibody, and who have demonstrated disease progression on the last therapy.

For complete product information, please see the Summary of Product Characteristics that will be posted at https://ec.europa.eu/health/documents/community-register/html/h1537.htm.

About Karyopharm Therapeutics

Karyopharm Therapeutics Inc. (Nasdaq: KPTI) is a commercial-stage pharmaceutical company pioneering novel cancer therapies and dedicated to the discovery, development, and commercialization of first-in-class drugs directed against nuclear export for the treatment of cancer and other diseases. Karyopharm’s Selective Inhibitor of Nuclear Export (SINE) compounds function by binding with and inhibiting the nuclear export protein XPO1 (or CRM1). Karyopharm’s lead compound, XPOVIO (selinexor), is approved in the U.S. in multiple hematologic malignancy indications, including in combination with Velcade® (bortezomib) and dexamethasone for the treatment of adult patients with multiple myeloma after at least one prior therapy, in combination with dexamethasone for the treatment of adult patients with heavily pretreated multiple myeloma and as a monotherapy for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma. NEXPOVIO (selinexor) has also been granted conditional marketing authorization in combination with dexamethasone for adult patients with heavily pretreated multiple myeloma by the European Commission. In addition to single-agent and combination activity against a variety of human cancers, SINE compounds have also shown biological activity in models of neurodegeneration, inflammation, autoimmune disease, certain viruses and wound-healing. Karyopharm has several investigational programs in clinical or preclinical development. For more information, please visit www.karyopharm.com .

XPOVIO® and NEXPOVIO® are registered trademarks of Karyopharm Therapeutics Inc. Velcade® is a registered trademark of Takeda Pharmaceutical Company Limited.

References
¹ World Health Organization. 2020. https://gco.iarc.fr/today/data/factsheets/cancers/35-Multiple-myeloma-fact-sheet.pdf

Contact:

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