Cell Therapeutics is an unhappy company this week as a U.S. advisory panel that advises the FDA said the company had not collected enough data to win clearance for an experimental lymphoma drug. In a 9-0 vote, the panel said the company's single trial of pixantrone was inadequate. Pixantrone belongs to the family of drugs called antitumor antibiotics
"I don't see this as being a well-designed or well-executed study," said Dr. Wyndham Wilson, a panel member and a lymphoma specialist at the National Cancer Institute. That means the FDA is probably going to nix approval as they usually follows panel recommendations, and FDA scientists who spoke to the committee also were critical of the company's study.
Cell Therapeutics wants to sell pixantrone under the name Pixuvri for treating non-Hodgkin's lymphoma that has stopped responding to other treatments. The blood cancer affects about 66,000 Americans annually.
The company said pixantrone offered an effective therapy for patients whose cancer worsened after at least two prior chemotherapy regimens. Patients at that stage have no approved treatments and often live less than six months.
In the Cell Therapeutics study of 140 patients, 20 percent had a major decrease in their disease if they got pixantrone, compared to about 6 percent with a different medicine. FDA reviewers questioned the company's conclusions, arguing that the study tested less than half the number of people originally planned and included just eight U.S. patients. The agency also said heart damage and decreased white blood cells were more common with pixantrone versus other cancer drugs.
"This drug has some activity. I don't think anybody on this committee would debate that point. The population enrolled in this study, however, doesn't reflect the U.S. population of lymphoma patients," said Dr. Mikkael Sekeres, an oncologist at the Cleveland Clinic.
Unlike other drugs in this class that cause serious tissue necrosis if they pass through the walls of vessels into surrounding tissue, pixantrone can be given through a peripheral vein and does not require a central implanted catheter.