WASHINGTON — The head of the U.S. Food and Drug Administration conceded Monday that the agency acted too slowly in moving against potentially deadly artificial heart valves manufactured by Irvine-based Shiley Inc. in the early 1980s.
"As you look back over this, our track record doesn't look real good," James S. Benson, acting FDA commissioner, said at a daylong hearing conducted by the investigations subcommittee of the House Energy and Commerce Committee.
The hearing focused on the FDA's oversight of Shiley, the heart-valve maker that is owned by pharmaceutical giant Pfizer Inc. Shiley employs 1,100 at its Orange County plant.
Panel members are exploring ways to get faster agency action against problem products.
Since the first of two Shiley valves that are at the center of the controversy went on the market in 1979, the company has reported a total of 389 failures resulting in 272 deaths. About 85,700 of the two valve models were produced. They were designed to replace diseased or damaged heart tissue that regulate the flow of blood through the organ.
One model was withdrawn by the company in 1986 after the FDA began moving to suspend its sale. The other was sold only overseas between 1980-83.
FDA officials said the slow pace of the agency's enforcement was partially due to the time it took to develop regulations to evaluate new heart valves--which came under FDA oversight in 1976--and to Shiley's stubborn resistance to the agency's efforts.
Shiley officials, however, insisted that they have fully cooperated with the agency.
"Shiley diligently sought to eliminate the (failure) problem through a variety of actions," said Dr. Roger Sachs, Shiley vice president and medical director. Among other things, Shiley convened internal research committees and hired outside research firms to study the problem, he said.
Both Shiley and government investigators agree that the precise cause of the failures, which occur in one of two "struts" that hold the artificial valve in place, was never determined.
The congressional investigation of the FDA's relationship with Shiley is the latest inquiry that has produced criticism of the agency. Its problems have included a scandal in the generic drugs division involving disclosures of bribery and mismanagement and continuing criticism of the FDA's performance in regulating food imports and other items.
Rep. John D. Dingell (D-Mich.), chairman of the Energy and Commerce Committee, has been one of the agency's most vocal critics.
In his testimony Monday, Daniel J. Chwirut of the FDA's Division of Mechanics accused Shiley of producing a heart valve of "marginal design" that was so sensitive to production imperfections that "you would have to have an almost perfect manufacturing operation in order to get the valve to function properly."
In addition, Chwirut criticized Shiley's quality-control procedures and said the company appeared to willfully hamper the FDA's attempts to investigate the causes of the heart-valve failures.
"They were definitely being less than fully honest with the agency in terms of submitting the data that we'd asked for," Chwirut said. "My impression was that they were not close to finding a solution to the problem."
Yet the FDA permitted Shiley to continue to market its "60-degree, convexo-concave" valve in the United States, Benson testified, because the agency mistakenly believed that the Shiley valve was less prone to producing dangerous blood clots than other artificial heart valves.
"We believed that taking the . . . valve off the market might have deprived surgeons and patients of the better product," Benson said in written testimony presented to the subcommittee.
By early 1986, the agency changed its mind, concluding from new statistical analyses that the valve offered no advantages with blood clots and that its mechanical failure rate was greater than other heart valves. The company voluntarily withdrew the 60-degree valve later that year.
Benson said the FDA should have been more aggressive.
That view was shared by Frederick Barbee of Minong, Wis., who testified that his wife Carol might have lived had Shiley informed him that the valve implanted in his wife's heart was prone to failure. Shiley has said its policy was to notify doctors of potential problems, but not patients.
"It appears that the thing that is of greatest concern is profit," Barbee testified.