Karyopharm Chapter 11 Puts Selinexor Myelofibrosis Phase 3 Bet on $55M Lifeline

Karyopharm Files for Bankruptcy, Pursues Merger with Ayrmid

Karyopharm Therapeutics has filed for Chapter 11 bankruptcy and is pursuing a merger with U.K. biotech Ayrmid, which is serving as the lead bidder in a court-supervised sale expected to close in Q1 2027. To support its ongoing operations, including multiple myeloma and myelofibrosis programs, during this process, Karyopharm secured commitments for up to $55 million in debtor-in-process financing from existing secured lenders. This strategic move follows previous reports of significant financial strain, aiming to provide a stable path forward for the company.

• Karyopharm Therapeutics initiated Chapter 11 bankruptcy proceedings due to severe financial challenges, having previously disclosed insufficient cash reserves to extend beyond September. This filing aims to provide a structured path forward for the company amidst its financial difficulties and ensure continued operations.
• The bankruptcy is coupled with a planned merger with Ayrmid, a U.K. biotech, which is acting as the lead bidder in a court-supervised sale. The transaction is anticipated to finalize in the first quarter of 2027, with Karyopharm securing up to $55 million in debtor-in-process financing to maintain operations during the transition.
• Despite the restructuring, Karyopharm is committed to advancing its multiple myeloma and myelofibrosis programs, operating in the ordinary course of business. Ayrmid has indicated an intention to retain the majority of Karyopharm’s workforce, suggesting that no layoffs are directly linked to this merger announcement, preserving key organizational capabilities.

Addressing Unmet Needs in Multiple Myeloma: A Strategic Imperative

Recent literature highlights persistent unmet needs in multiple myeloma despite advances in treatment. Priorities include improving outcomes for patients with heavily pretreated or refractory disease, renal impairment, and biologically or clinically high-risk disease.

• Heavily pretreated and refractory RRMM: Patients refractory to multiple drug classes, including those previously treated with lenalidomide and anti-CD38 monoclonal antibodies, have poor survival outcomes and limited treatment options. Novel therapies and improved sequencing strategies are key areas of focus.

• Renal impairment and dialysis dependence: Dialysis-dependent patients continue to have poor outcomes. Studies identify dialysis independence and renal recovery as important clinical challenges, particularly for patients with newly diagnosed disease.

• High-risk disease and extramedullary involvement: High-risk cytogenetics and extramedullary disease are associated with inferior outcomes. Research is evaluating whether CAR-T-cell and bispecific antibody therapies can address these populations’ needs.

• Plasma cell leukemia and other difficult-to-treat groups: Plasma cell leukemia, including secondary plasma cell leukemia, remains associated with poor survival and a need for better treatment options. Other populations with unmet needs include elderly and frail patients and those with central nervous system involvement.

Expanding Xpovio's Reach Beyond Multiple Myeloma

Beyond multiple myeloma, selinexor is being evaluated across hematologic and solid tumors, including endometrial cancer, acute myeloid leukemia (AML), myelofibrosis, and several other malignancies. The intervention models include selinexor monotherapy, placebo- or physician’s-choice-controlled studies, and combinations with chemotherapy or targeted agents.

Navigating the Evolving Multiple Myeloma Treatment Landscape

In newly diagnosed, transplant-eligible multiple myeloma, induction has moved toward anti-CD38-containing combinations and deeper response assessment. In the phase 3 GMMG-HD7 trial, adding isatuximab to lenalidomide, bortezomib, and dexamethasone increased minimal residual disease (MRD) negativity after induction to 50%, versus 36% with the triplet (OR 1·82 [95% CI 1·33-2·48]; p=0·00017). In the phase III IFM2020-02-MIDAS study, six cycles of isatuximab, carfilzomib, lenalidomide, and dexamethasone yielded MRD-negativity rates of 63% at 10-5 and 47% at 10-6. A 2026 systematic review of 11 trials reported higher MRD-negativity with anti-CD38 regimens in transplant-eligible and transplant-ineligible patients, and significantly prolonged progression-free survival in both groups.

For older, transplant-ineligible patients, the GEM-2017FIT phase 3 trial found higher undetectable MRD rates after 18 cycles with carfilzomib, lenalidomide, and dexamethasone (54%) or daratumumab added to that regimen (61%) than with bortezomib, melphalan, and prednisone followed by lenalidomide and dexamethasone (27%). Grade 3-4 neutropenia was lower with the carfilzomib triplet than with the other two regimens, while toxicity-related death was significantly higher in the daratumumab quadruplet group. These results sit alongside continued attention to frailty-based assessment and MRD-guided strategies; the MIDAS analysis reported that 96% of patients completed induction and that the median CD34+ cell yield was 7 × 106/Kg.

In relapsed or refractory disease, the literature describes a broader range of approaches, including bispecific antibodies, cellular therapies, and novel combinations. Teclistamab produced a response in 63% of participants in the MajesTEC-1 study after approximately 14.1 months of follow-up; the review literature describes BCMA-targeted CAR-T therapies as providing durable responses in heavily pretreated, triple-class refractory patients. Iberdomide plus dexamethasone showed an overall response rate of 26% in the dose-expansion cohort of the phase 1/2 CC-220-MM-001 trial. Bispecific antibodies have established clinical activity in B-cell precursor acute lymphoblastic leukemia, B-cell non-Hodgkin lymphoma, and multiple myeloma, while cytokine release syndrome, neurotoxicity, cytopenias, and infections remain key safety considerations.