The U.S. Food and Drug Administration has granted fast track status to Forty Seven’s lead candidate Hu5F9-G4 for the treatment of relapsed or refractory diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma.
The designations are expected to facilitate the clinical development of Hu5F9-G4 (or just 5F9) and expedite the FDA’s review for the treatment of these two B-cell non-Hodgkin’s lymphoma (NHL) subtypes.
“The FDA’s decision to grant Fast Track designations to 5F9 for the treatment of DLBCL and follicular lymphoma reflects the urgent need for safe and effective therapies for people living with these cancers, and the potential of 5F9 to help patients for whom existing options are limited,” Mark McCamish, an MD and PhD, president and CEO of Forty Seven, said in a press release.
5F9 is an antibody that targets the CD47 factor, blocking the “don’t eat me” signal used by cancer cells to avoid being ingested by macrophages — a kind of immune cell that engulfs invaders.
The investigative therapy works like checkpoint inhibitors. But instead of activating T-cells, it improves the ability of macrophages to identify cancer cells and eliminate them.
Because this evading mechanism is used by several cancer types, Hu5F9-G4 represents a promising approach for a wide range of solid and blood cancers.
The newly granted fast track designations were supported by preliminary results of an open-label Phase 1b/2 clinical trial (NCT02953509) being conducted in collaboration with the Leukemia & Lymphoma Society.
The trial, which is still recruiting, will include 72 lymphoma patients across 11 clinical sites in the U.S. and the U.K.
“We look forward to working closely with the FDA as we advance our ongoing Phase 2 trial of 5F9 in combination with rituximab and continue to learn about the safety and efficacy profile of 5F9 in patients with B-cell NHL,” McCamish said.
The trial is twofold. In the Phase 1b part, participants will receive once-weekly infusions of ascending doses of 5F9 in combination with Rituxan.
After selecting the dose with the best preliminary efficacy and fewest adverse effects, researchers will initiate the Phase 2 part, to further test the safety and efficacy of the selected dose of Hu5F9-G4.
Forty Seven is planning to announce initial results from the Phase 1b part by July of this year.
The company is also assessing 5F9 as a treatment for refractory acute myeloid lymphoma (AML) and myelodysplastic syndrome — a blood disorder characterized by low levels of certain blood cells — in Phase 1 trials.
The therapy candidate is also being studied as a treatment for ovarian, bladder, and other solid tumors in additional Phase 1/2 trials.