Why Are Karyopharm Therapeutics Shares Gaining Today?

Karyopharm Therapeutics Inc KPTI shares are trading higher after the FDA granted Fast Track Designation to the development program of selinexor for myelofibrosis, including primary myelofibrosis, post-essential thrombocythemia myelofibrosis, and post-polycythemia vera myelofibrosis.

Myelofibrosis is a rare type of blood cancer characterized by the buildup of scar tissue, called "fibrosis," in the bone marrow.

In June 2023, Karyopharm initiated a pivotal Phase 3 trial (XPORT-MF-034) to assess the efficacy and safety of once-weekly selinexor 60 mg in combination with ruxolitinib in JAKi-naïve patients with myelofibrosis. 

Updated data from the Phase 1 study were presented at the American Association for Cancer Research Annual Meeting, American Society of Clinical Oncology, and European Hematology Association 2023, which showed rapid, deep, and sustained spleen responses and robust symptom improvement in patients treated with selinexor 60 mg in combination with ruxolitinib as of the April 10, cut-off date. 

Top-line data from the Phase 3 study is expected in 2025. 

The company plans to expand its clinical development program in myelofibrosis by investigating selinexor in other JAKi-naïve settings.

Price Action: KPTI shares are up 20.90% at $1.85 during the premarket session on the last check Tuesday.