U.S. Food and Drug Administration reviewers are divided on whether an intravenous blood clot preventer developed by The Medicines Co should be approved, news that sent the company's stock down more than 7 percent on Monday.
Medical Team Leader Dr. Thomas Marciniak recommended the drug, cangrelor, not be approved, saying data did not show the product was as good as or superior to a rival drug. Another reviewer, Dr. Fred Senatore, recommended the drug be approved.
The review, posted on the FDA's website on Monday, came two days ahead of a meeting of outside experts who will make their own recommendation. The FDA is not required to follow the recommendations of its advisors but typically does.
Cangrelor is designed to prevent blood clots during heart artery-clearing angioplasty and stenting procedures. A clinical trial of more than 11,000 patients showed those taking cangrelor had a reduction in the combined risk of death, heart attack, repeat procedure or stent thrombosis, a blood clot that forms at the site of the stent.
Patients taking cangrelor had a 22 percent lower risk of experiencing one of these complications 48 hours after the procedure than those who took Plavix, a rival product made by Bristol-Myers Squibb Co. Patients taking cangrelor had a 38 percent reduction in stent thrombosis alone.
Marciniak took issue with the way the trial was conducted and the data interpreted, and said that "while the trials did not demonstrate convincingly superiority of cangrelor efficacy, they do demonstrate an increased risk of bleeding with it."
The trial, known as Champion-Phoenix, followed two failed trials. For the third trial the company changed the design to try to differentiate between heart attacks associated with the drug and those that may have been associated with the procedure.
Marciniak said the company should conduct an additional trial before the drug be considered for approval.
Senatore and another reviewer, B. Nhi Beasley, on the other hand, said the drug met the main goal of the clinical trial and should be approved.
Cangrelor and Plavix, known generically as clopidogrel, had similar rates of severe bleeding in the trial - 0.16 percent for cangrelor and 0.11 percent for Plavix.
If approved, cangrelor is expected to generate sales of about $226 million by 2018, according to Thomson Reuters data.
The Medicines Co's shares were trading $2.53 at $31.69 in early trading on Nasdaq.
(Reporting by Toni Clarke in Washington; Editing by Chizu Nomiyama and Paul Simao)