The NYC-based immuno-oncology focused developer BeyondSpring recently announced receipt of a Complete Response Letter from the U.S. FDA rejecting the company’s application for a treatment regimen to treat chemotherapy-induced neutropenia containing its lead drug, plinabulin.
At issue, according to regulators, is that the results of the single trial — testing plinabulin in combination with granulocyte colony-stimulating factor (G-CSF) — were not sufficiently robust to demonstrate benefit. The FDA says a second well controlled trial would be required to support the indication in CIN — a devastating side effect of chemotherapy.
BeyondSpring is developing plinabulin for both CIN and non-small cell lung cancer. The company has completed phase 3 trials in both indications and filed for approval in CIN in March.
Critics have raised red flags about the validity of BeyondSpring’s clinical trial data and its likelihood of approval in either indication. Concerns surrounded inadequate control of clinical trials and poor disclosure of results.
But despite the recent FDA rejection, BeyondSpring remains confident in the efficacy and safety data for plinabulin in combination with G-CSF for the prevention of CIN. The company said it plans to "work closely with the FDA to consider the possible future clinical pathway for CIN, which may include a second study."
