WASHINGTON--The U.S. Food and Drug Administration Monday said the benefit of a proposed Sanofi SA (SAN.FR, SNY) drug designed to prevent blood clots in cancer patients "appears to be very small" and questioned the clinical value of the product.
Sanofi is seeking FDA approval of a drug called semuloparin, a type of heparin, for use in preventing blood clots in certain cancer patients undergoing chemotherapy to treat cancer. The drug will be reviewed on Wednesday by the FDA's oncologic drugs advisory committee, which is made up of non-FDA medical experts.
The FDA posted a review of semuloparin on its website Monday in preparation for the advisory panel meeting.
Sanofi has said the drug can help cut the risk of developing blood clots in the body's deep veins, which is a life- threatening complication of cancer affecting up to one in five patients. The clots, known as venous thromboembolism or VTE, can migrate and block flow in blood vessels of the lungs, which may result in sudden death.
Sanofi looked at semuloparin in a study involving more than 3,000 patients who were undergoing chemotherapy for a variety of cancers. About half of the patients received semuloparin and the other half received a placebo or a fake drug for a minimum of three months.
The study looked at VTEs that were causing symptoms and VTE-related deaths. The study showed 1.2% of patients receiving semuloparin had a VTE or related death compared to 3.4% of patients not receiving the drug, which met a study goal showing the drug was effective. However, the FDA said the observed treatment difference was driven by nonfatal VTE events.
The agency also said there was a higher number of bleeding related events among patients receiving semuloparin including one death from bleeding in the brain.
"These findings call into question the clinical value of semuloparin in the proposed clinical setting," FDA said.
Sanofi, in a document also posted to FDA's website, said "semuloparin is an effective and safe therapy for the [ prevention] of VTE in patients with cancer receiving chemotherapy."
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