Inrebic Receives FDA Approval for Adults with Myelofibrosis

Web Exclusives - FDA Updates

On August 16, 2019, the FDA approved fedratinib (Inrebic; Celgene/Impact Biomedicines), an oral kinase inhibitor, for adults with intermediate-2 or high-risk primary or secondary—post–polycythemia vera (PV) or post–essential thrombocythemia (ET)—myelofibrosis, a rare bone marrow disorder. The FDA granted fedratinib priority review and an orphan drug designation.

“Myelofibrosis can cause patients to suffer in many ways, including experiencing debilitating symptoms,” said Ruben Mesa, MD, FACP, Director, Mays Cancer Center, San Antonio M.D. Anderson Cancer Center. “There has not been a new treatment approved for this disease in nearly a decade.”

The FDA approved fedratinib based on the JAKARTA study, a phase 3, double-blind, randomized, placebo-­controlled clinical trial of 289 patients with intermediate-2 or high-risk myelofibrosis, post-PV myelofibrosis, or post-ET myelofibrosis with splenomegaly. Patients were randomized to 400 mg or 500 mg of fedratinib or to placebo once daily for at least 6 cycles.

The primary outcome was the proportion of patients achieving ≥35% reduction from baseline in spleen volume after 6 cycles of treatment. Of the 96 patients who received 400 mg of fedratinib, 35 (37%) achieved a ≥35% reduction in spleen volume versus 1 of 96 patients who received placebo (P <.0001). The median duration of spleen response was 18.2 months with 400 mg of fedratinib. In addition, 40% of patients who received the 400-mg dose had a ≥50% reduction in myelofibrosis-related symptoms versus only 9% of patients receiving placebo.

The most common (≥20%) side effects were diarrhea, nausea, anemia, and vomiting. Fedratinib was approved with a boxed warning about the risk for serious and fatal encephalopathy, including Wernicke’s encephalopathy.

Related Items
FDA News: October 21, 2022, and December 1, 2022
TOP - January 2023 Vol 16, No 1 published on January 10, 2023 in FDA Updates
FDA News: August 24, 2022, and September 30, 2022
TOP - November 2022 Vol 15, No 6 published on November 9, 2022 in FDA Updates
FDA News: June 22, 2022, and August 11, 2022.
TOP - September 2022 Vol 15, No 5 published on September 15, 2022 in FDA Updates
FDA News: April 1, 2022, and May 27, 2022
TOP - July 2022 Vol 15, No 4 published on July 20, 2022 in FDA Updates
FDA NEWS: February 28, 2022 to March 31, 2022
TOP - May 2022 Vol 15, No 3 published on May 6, 2022 in FDA Updates
FDA NEWS: January 10, 2022, and January 25, 2022
TOP - March 2022 Vol 15, No 2 published on March 16, 2022 in FDA Updates
FDA NEWS: November 29, 2021, and December 15, 2021
TOP - January 2022 Vol 15, No 1 – Online Only published on January 20, 2022 in FDA Updates
FDA NEWS: August 13, 2021 to September 22, 2021
TOP - November 2021 Vol 14, No 7 published on November 10, 2021 in FDA Updates
FDA Issues Revised Final Guidance on Biosimilar Development and the BPCI Act
TOP - October 2021 Vol 14, No 6 | Biosimilars published on November 5, 2021 in FDA Updates, Biosimilars
FDA NEWS: June 30, 2021, and July 26, 2021
TOP - September 2021 Vol 14, No 5 published on September 7, 2021 in FDA Updates
Last modified: July 22, 2021