The U.S Food and Drug Administration has denied entry to more than 30 generic drugs made by India’s Ranbaxy Laboratories into the United States, citing poor quality. The FDA’s Import Alert blocks the import of generic drugs, which include the cholesterol-lowering drugs simvastatin and pravastatin, the antibiotic clarithromycin, the HIV drugs lamivudine and zidovudine, as well as the diabetes drug metformin.

Dr. Douglas Throckmorton, deputy director of FDA's Center for Drug Evaluation and Research, during an afternoon teleconference Tuesday said, "FDA is taking this proactive step to ensure that drugs from these two facilities are not allowed into the United States until they meet FDA requirements for quality drug manufacture." He added, "To date, we have seen no evidence of harm to consumers from drugs produced at these two facilities and have no reason to believe that drugs already in the United States from these plans pose a safety problem."

Shortage of drugs was not expected as Throckmorton said other suppliers would be able to fulfill the demand. "Based on what we know today, consumers who use products affected by this import alert should not discontinue their drug therapy, as such action could seriously jeopardize their health," Throckmorton said.

One of the world's largest producers of generic drugs, Ranbaxy is the sole supplier of the antiviral drug ganciclovir used to treat an eye infection called cytomegalovirus that is common in HIV patients. The FDA will not hold up shipments to avoid a shortage of this drug, but will provide stepped-up oversight until the company fixes its problems, Throckmorton said.

Deborah Autor, director of FDA's Office of Compliance, Center for Drug Evaluation and Research said earlier this year, FDA inspections found violations that could lead to contamination, allergic reactions and other problems, and the company hasn't taken proper steps to correct them. No new products sale by Ranbaxy would be approved by the FDA until these manufacturing violations are corrected. "These problems included failure to retain complete drug testing data, insufficient documentation to demonstrate stability tests were valid, and lack of sufficient laboratory personnel and instrumentation," Autor said. Further investigation showed there was inadequate sterile processing of penicillin products, Autor said. The agency did not feel that an import alert was justified before Tuesday’s action.

"The deficiencies in the process have reached a level where we feel an import alert is justified," Autor said. "The firm is sufficiently out of control that we feel an import alert should be put in place until the deficiencies are corrected," she said.

The FDA has said that the two affected plants are in Dewas and Paonta Sahib, India and they have deficiencies in the manufacturing process. The FDA has said that repeated testing has not found any contaminated products but there is a threat of contamination if the factory conditions don’t improve. They have asked consumers who have Ranbaxy products at home not to worry or quit using them as it would be hard for a patient to tell if drugs were made at the suspect factories or at one of Ranbaxy's numerous other factories in 11 countries.

There is a separate criminal investigation continuing of whether Ranbaxy submitted fraudulent data to the FDA that allowed sale of substandard drugs, a claim that Ranbaxy strongly denies calling it part of a conspiracy to undermine the company.

India has become one of the world's leading suppliers of generic drugs, and Ranbaxy is one of the largest suppliers of generic drugs to the United States with worldwide sales of $1.61 billion, 25 percent or $386 million worth of which are to the U.S.

As Ranbaxy is one supplier of the low-cost generics for AIDS drugs to Africa, the ban could affect it as well. Charities and officials involved in the AIDS drug program had been notified of concerns about drug quality the FDA said.

Rep. John Dingell, D-Mich., whose House Energy and Commerce Committee is conducting that investigation said, "The FDA is not doing its best to protect the medicines that Americans depend on for their health."