After reviewing 27,000 pages of documents from the Food and Drug Administration, Republicans and Democrats came to different conclusions about the agency’s ability to prevent one of the worst public health crises in American history.

Republican members of the House Energy and Commerce Committee said Tuesday that its six-month investigation into the FDA’s role in last fall’s meningitis outbreak shows the agency knew for a decade about serious safety lapses at the specialized pharmacy that made the tainted drugs but failed to act.

Democrats said they believe the documents paint a different picture, one of an agency that made some efforts to rein in the Massachusetts-based New England Compounding Center (NECC), which made the contaminated steroids tied to the outbreak that has so far killed 53 people. However, they were thwarted by the Bush administration and by ambiguous federal laws and conflicting court rulings that do not give the FDA clear authority over compounders.

The documents show that, dating back to at least 2002, the FDA had received and largely ignored complaints from doctors, nurses and whistleblowers about safety problems at the NECC, according to the majority report from the Republicans. The complaints prompted two inspections, but, even as new complaints rolled in and after the agency issued a warning letter in 2006, the FDA did not return to the facility until after the outbreak.

“We know now that 53 Americans did not need to die,” said the committee chairman, Rep. Fred Upton (R-Mich.). “It sickens me that this could have been avoided.”

FDA commissioner Margaret A. Hamburg, the only person scheduled to testify at the hearing, was sharply criticized about the agency’s efforts with the NECC.

Members repeatedly asked why the agency has been able to conduct stepped-up inspections in recent months if they lack authority to do so. Earlier this month, the FDA released initial results of a targeted inspection of 30 compounding pharmacies, showing many of the firms had potentially dangerous safety violations.

“I wish we had been more aggressive,” Hamburg told the committee.

“I bet the families who have lost loved ones wish you had acted as well,” said Rep. Renee L. Ellmers (R-N.C.).

Hamburg told members that although the FDA is being more aggressive now, compounders are challenging their authority. In two recent instances, compounding pharmacies refused to give FDA inspectors access to the facility or records, so the agency had to secure warrants.

Hamburg asked for legislation that would require large, ­manufacturing-style compounding pharmacies to register with the agency and provide detailed information about the products they make. She said federal law must also make it clear that they have the right to conduct inspections, view pharmacy documents and order changes when they identify safety lapses.

The documents show that much of the delay was the result of internal agency debate about whether and how to proceed, in anticipation of having to defend an enforcement action.

“We are picking at gnats and straining at flies. We should be trying to figure out what are the problems,” said Rep. John D. Dingell (D-Mich.). “We are dealing here with an agency that doesn’t have the authority to do the things they need to do.”

The committee’s majority report from Republicans also criticized the agency for failing to take action against the NECC’s sister company, Ameridose, which was inspected by the agency in 2007 and 2008 and had to recall a painkiller in 2008 because it was too strong. The report details numerous complaints the agency received about potential safety problems with Ameridose’s products but delayed further action.

The majority report also faulted the FDA for failing to share information it had on the NECC and Ameridose with state regulators.

Democrats released their own report that cited internal e-mails and other documents to back their claims that the Bush administration stymied the FDA’s efforts to send warning letters to the NECC and that this was partially to blame for the agency’s inaction.

One August 2006 e-mail, written by a director in the FDA’s complaint division to appointees in the agency’s legal office, said: “I’m very frustrated that we still don’t have a decision from your office about these warning letters. . . . For these letters to still be pending at this late date, especially given these extraordinary and unusual measures, is troubling.”

Lena H. Sun contributed to this report.

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