In the latest attack by senior lawmakers against the Food and Drug Administration, the chairman and ranking member of the Senate Finance Committee are asking the FDA to respond to a recent independent study that blamed agency dysfunction for delays and cost overruns in establishing a drug safety review system.

Sens. Max Baucus (D-Mont.) and Chuck Grassley (R-Iowa) want FDA Commissioner Andrew von Eschenbach to explain by April 2 why the development of new drug-review software has experienced problems. The lawmakers’ March 1 letter specifically refers to a review of the Adverse Events Reporting System II by the Breckenridge Institute, a think tank that studies organizations and management. The agency has been planning to use that system to track problems with drug products after they’ve been approved by the FDA.

The report’s findings prompted the Senators, who are frequent critics of the FDA, to slam the agency.

“We all rely on the FDA for drug safety, and this report raises some troubling questions about how wisely the FDA spends money and how well they’re protecting us,” Baucus said in a statement. Grassley added, “This report is more evidence of a broken-down process inside the FDA.”

The report comes as the agency already has been under fire from the Government Accountability Office, the Institute of Medicine and watchdog groups for its handling of drug safety issues.

Alleged FDA mishandling of drugs, such as the antibiotic Ketek (telithromycin) made by sanofi-aventis, have attracted attention in the public and in Congress in recent months. Baucus and Grassley have accused the FDA of using faulty data to approve the drug and of withholding their concerns about this information from an agency advisory panel.

Drug safety issues also have taken a leading role in ongoing reauthorization of drug user fees.

The institute’s November 2006 report, which was publicly released March 6, found significant flaws in the FDA’s culture that prevented managers from properly addressing organizational problems in development of the software.

The agency’s culture “can be characterized as one in which managers at all organizational levels fail to move from the awareness of organizational problems to the kind of action that will produce positive change,” the report said. Any attempts to effect change are “frustrated and undermined by an ‘invisible bureaucracy,’ that they don’t really understand,” the report added.

The report’s authors concluded that this organizational problem led to a four- to five-year delay in implementing the new $25 million tool, costing an unnecessary $1.5 million and leaving the agency less prepared to improve its drug safety efforts than when AERS II began to be developed in 2004, the institute said.

To address that problem, the agency needs a “significant change” in its culture, the Breckenridge Institute concluded.

The FDA rejected the report as “riddled with editorial conclusions based on misleading or incorrect facts,” Doug Arbesfeld, the agency’s senior communications adviser, said in a statement today. The current system “works well despite handling huge amounts of data. The FDA wants to develop a replacement to AERS, but we want it to be done right.”