Shire is to appeal a move by regulators in the USA to seek the withdrawal of the firm's hypotension drug ProAmatine even though it had originally agreed to pull the treatment.

Last month, the US Food and Drug Administration issued a Proposal to Withdraw Marketing Approval for ProAmatine (midodrine) and a Notice of Opportunity for a Hearing to Shire and generic manufacturers of the drug. The latter was approved in the USA in 1996 under the accelerated approvals process. However, according to the agency neither Shire nor any generic firm has since demonstrated ProAmatine's clinical benefit, and so had begun the process to remove its marketing approval.

Shire originally said it had indeed conducted several clinical studies of the drug, "and literature regarding the efficacy of the product has been published", but as the post-marketing data submitted to the FDA was not deemed to be sufficient, it would go along with the agency's decision and start withdrawing ProAmatine from September 30. Sales of the drug represent less than 0.1% of Shire’s total revenues and it is thought that the company was not keen on funding any more trials.

Now the company has told the FDA it does want a public hearing, so it can present data supporting the clinical benefit of ProAmatine and for an advisory committee to review them. The agency seems very amenable to the idea and said that since it announced the proposed withdrawal "we have heard from professional organisations, doctors and patients about their concern about losing access to midodrine".

Other groups have expressed interest in conducting the clinical studies necessary to establish effectiveness, "as well as doctors and patients who support the conduct of such studies", the FDA added. The agency concluded by saying that "midodrine remains approved and available in the marketplace; continued patient access...is a key agency priority".