Advisors to the US Food and Drug Administration has issued a resounding 'no' to Sanofi's investigational anticoagulant semuloparin.

The agency's Oncologic Drugs Advisory Committee voted 14 to 1 (with one abstention) not to recommend approval of semuloparin for the prevention of venous thromboembolism (VTE) in patients receiving chemotherapy for metastatic lung or pancreatic cancer. The panel also rejected the drug for use in patients with advanced solid tumours with a VTE risk score greater than or equal to three.

The vote was not unexpected given that FDA staffers, in documents released earlier this week, said the file for semuloparin did not provide meaningful support for approval. The submission is based on the SAVE-ONCO trial, which included 3,212 patients, and the results  revealed that 1.2% of patients receiving semuloparin, a new low-molecular-_weight heparin, had a VTE or related death, compared to 3.4% on placebo.

However the ODAC described this benefit as modest and also expressed concern about bleeding-related events. Also around 5% of patients died from other causes, which led to panellists questioning the validity of preventing VTE in these patients.

Richard Pazdur, director of the FDA’s Office of Hematology and Oncology Drug Products, told the committee that"we still have a lot of unanswered questions,” saying that "you also have to define in labelling a patient population that is most likely going to benefit from this drug".

Sanofi said it is disappointed with the vote as there are currently no anticoagulants approved for this specific indication.  It adds that "often clinically silent, VTE is a potentially life-threatening complication of cancer and its treatment that may increase morbidity, mortality and medical care and cost".