By Maggie Fox

Reuters 22 March 2002

Washington -- Researchers rushed on Friday to defend an important drug that fights the AIDS virus, saying they feared a U.S. government review of African trials of the drug would give South Africa's government an excuse to reject it.

Nevirapine is one of the standard drugs used in cocktails that can suppress the virus. It can also help protect newborns from catching the virus from their mothers.

But South African President Thabo Mbeki has questioned whether HIV actually causes AIDS and has moved slowly in allowing the use of HIV drugs in his country, although South Africa has the highest rate of HIV infection in the world.

A single Nevirapine pill given to the mother, and a single dose given to the baby at birth, can cut the cases of mother-to-child transmission of the AIDS virus in half.

Studies that demonstrated this were done in Uganda in 1999 by researchers at Johns Hopkins University, the U.S. National Institute of Allergies and infectious Diseases (NIAID) and Ugandan researchers.

When the results came out, the German manufacturer of the drug, Boehringer Ingelheim, said it would make it available free in developing countries, where most of the 40 million people infected with HIV live, to prevent mother-to-child transmission.

It applied for approval from the U.S. Food and Drug Administration to market Nevirapine for this purpose in the United States.

Sold under the name Viramune, the drug is already widely prescribed for adults and children, and doctors are free to prescribe it any way they wish. But FDA approval is needed for the company to actively promote the drug for use in preventing mother-to-child transmission in the United States.

When scientists started going through the data from the 1999 trial done in Uganda, some "procedural" problems were found, Boehringer and the NIAID said.

The NIAID told the FDA, which started an investigation.

Drug is Safe and Works Well, Experts Say

The company, government researchers and the FDA itself stressed that Nevirapine is considered safe and useful. "The issues with this study in no way affect the safety and efficacy of the product as currently labeled in the United States," an FDA spokesman said.

But, he added, "FDA believes that these problems are potentially quite serious. We can't say how they will affect the conclusions of the study."

South Africa's Medicines Control Council said on Thursday it would consider reviewing the drug in the light of the FDA's findings. This immediately raised hackles among AIDS activists and researchers.

"I am concerned that people would take this information and misuse it and not look at exactly what this all means," Sandy Thurman, who advised former president Bill Clinton on AIDS and who is now president of the International AIDS Trust, said in a telephone interview.

"The bottom line is we have 600,000 children born every year in Africa to HIV-infected mothers. If we err on the side of caution at this time, we lose literally thousands, if not hundreds of thousands, of lives in the process."

Johns Hopkins spokeswoman Joann Rodgers said the FDA concerns involve paperwork and documentation, not the actual findings from the trial.

"One of the things they always require are access to primary records," she said. "These records were often difficult to obtain. This is not unusual for research done in developing countries. These records sometimes are in cardboard boxes with no alphabetization, no names on them," she said.

"There is no evidence of any underreported deaths or of deaths or harm to mothers or babies that could be attributed to the drugs used in the study."

The company said it was in the meantime withdrawing its application to label the drug for use in preventing mother-to-child transmission in the United States -- labeling which, is approved, would give it a six-month extension on its patent for Nevirapine.