Merck & Co’s muscle relaxant Bridion has been available in the EU for five years, but the company has once again failed to convince the FDA that it should reach the US market.
Bridion (sugammadex sodium) has been turned down for the second time by the US regulator, this time because of questions surrounding a trial of the drug’s tendency to cause hypersensitivity reactions that was requested by the FDA when it turned Bridion down for the first time in 2008.
Sugammadex is used to reverse the effects of muscle relaxants given during surgery, such as rocuronium or vecuronium, and is claimed to help patients come out of anaesthesia more quickly and with fewer side effects than competing agents.
The latest complete response letter (CRL) from the FDA has “raised concerns about operational aspects of [the] hypersensitivity study”, according to Merck, which said it was still hoping to bring the drug to hospitals, surgeons, anaesthesia professionals and patients in the US.
The FDA recently conducted an audit of the clinical trial site that carried out the hypersensitivity study, and the findings of the inspectors prompted the agency to cancel an advisory committee meeting due to be held in July.
Bridion is already a useful earner for Merck, bringing in $260m last year but well shy of the $500m-plus analysts expect the drug can make if it wins approval in the US. However, the delay has damaged its prospects by allowing competing drugs – notably Flamel’s Bloxiverz (neostigmine) – to reach the market first.
Sugammadex is currently marketed in more than 50 countries other than the US, and more than 5m vials have been sold as of June 2013, said the firm.
The latest setback comes as Merck is in the process of revamping its R&D operations under the leadership of Roger Perlmutter, who replaced former R&D head Peter Kim earlier this year after disappointments such as the failure of cholesterol drug Tredaptive (extended-release niacin/laropiprant).
Setbacks have continued to dog Merck since then, including a knockback for much-anticipated insomnia treatment suvorexant by the FDA in July and a delay in the filing of osteoporosis treatment odanacatib, and some investors have called for an acceleration in the company’s R&D restructuring plans to reduce costs and boost productivity.