US President George Bush has officially nominated Andrew von Eschenbach as his candidate for the post of Food and Drug Administration (FDA) Commissioner, although it seems a rapid confirmation by the Senate is unlikely.

Von Eschenbach has been acting Commissioner at the FDA since the shock resignation of Lester Crawford in September 2005, just three months after taking up the post on a permanent basis.

The new nomination has been praised by Health and Human Services Secretary Mike Leavitt.

“Andy is an inspired choice to provide permanent leadership at this critical agency. His career has been defined by his vision for progress in research and passion for the care of patients,” he said in a statement.

But almost immediately after von Eschenbach’s nomination was announced, US Senators Hillary Rodham Clinton and Patty Murray said they will not vote on it unless the FDA moves ahead with its review of an application to make the emergency contraceptive Plan B available without a prescription.

Debate over the FDA’s alleged reluctance to approve Plan B also dragged out Crawford’s nomination process. The file for the morning-after pill has languished at the agency for two years, drawing accusations that the Bush Administration has pressured the agency to shelve it on ideological grounds.

Sens Clinton and Murray eventually withdrew their opposition to Crawford’s nomination after receiving assurances that progress would be made on Plan B application, but several months on – and with no sign that the review is closer to competition – they may be less inclined to do so on this occasion.

- Meanwhile, von Eschenbach was in front of Congress earlier this week insisting that the FDA will take greater steps to tackle a backlog in generic drug applications. Critics have suggested that the agency is more inclined to process applications for new medicines than generics, because the latter do not generate income from fees. The acting Commissioner said the FDA was "equally committed" to generic and brandname medicines, according to a Reuters report.