Epix Pharmaceuticals received a blow from US regulators yesterday, which turned down a formal appeal to approve its blood imaging agent Vasovist (gadofosveset trisodium).

According to Epix, the US Food and Drug Administration also denied its request for an advisory committee meeting to review data for product, suggesting instead that it carry out two extra clinical trials to help get Vasovist approved.

“We are evaluating several options available to us as next steps with Vasovist in the United States, including the option to appeal this decision to the next level at the FDA, and will update the market accordingly,” Andrew Uprichard, President of the firm, said in a statement.

The FDA first rejected Vasovist in November last year, asking for 'at least one' additional clinical trial of the product, as well as a re-appraisal of the images obtained in previously completed Phase III trials, before it could approved the drug, used in magnetic resonance imaging (MRI) procedures. But the company then appealed this decision in June.

News of the failed appeal came as a big disappointment to Epix’ shareholders, and the group’s stock dropped nearly 13% on the news, closing at $6.28 on the Nasdaq.

Vasovist is already approved in Europe, where it is sold by Germany’s Schering AG, and was recently recommended for approval in Australia.