The U.S. Food and Drug Administration has grown too close to the drug companies it regulates, raising questions about whether its acting director should be given a permanent job, a top Republican Senator said Thursday.

In disputes last year involving the use of antidepressants by teenagers and the withdrawal of the popular painkiller Vioxx, said Sen. Charles Grassley, “the agency charged with protecting the public from unsafe prescription drugs was too cozy with the drug companies.”

The problems at FDA come at a time when “some drug companies are placing greed ahead of drug safety,” Grassley said. In a speech to the Consumer Federation of America, he cited Justice Department statistics that “there are currently under seal in the neighborhood of 100 whistle-blower cases involving allegations against over 200 drug companies.”

In the Vioxx case in particular, Grassley said, “the FDA allowed itself to be manipulated by Merck,” the drug’s maker.

Grassley said that while he is convinced that FDA Acting Commissioner Lester Crawford’s “heart is in the right place,” he noted that both controversies occurred “under his watch,” and suggested that he will not be prepared to support Crawford’s nomination to head the agency permanently “until he has answered some tough questions.”

Grassley also said that the FDA has not yet responded to several committee requests for documents, and that if Crawford cannot get his staff to answer Congress’s questions, it raises the question “is he the right man for the job?”

Grassley noted that he has already introduced legislation to make data from prescription drug clinical trials more widely available to the public and to doctors, and that he plans to introduce another bill “in the coming days” to establish an independent Office of Drug Safety within FDA that would report directly to the commissioner.

The problem with the current office, he said, is that it reports to the Office of New Drugs, whose officials are unlikely to admit they might have made a mistake in approving a product.

“If you want accountability, it doesn’t make sense to have the office that reviews the safety of drugs to be under the thumb of the office that puts the drugs on the market in the first place,” Grassley said.

When the FDA approves a drug, he said, “Consumers shouldn’t have to second-guess the safety of what’s in their medicine cabinets.”