May 11, 2012

OraSure HIV Test Has Risks of False Results, FDA Says

By Anna Edney - May 11, 2012 3:30 PM ET

People who use what could be the first completely at-home HIV test under development by OraSure Technologies Inc. (OSUR) risk receiving false results, U.S. regulators said in a report.

Outside advisers to the Food and Drug Administration should weigh whether the benefits of the kit are greater than the potential risk of false negative and false positive results, agency staff said in the report today ahead of a May 15 advisory panel meeting. Regulators are considering approval of the OraQuick In-Home HIV Test, which would be sold without a prescription and provide users with their HIV status at home in a similar fashion to pregnancy tests.

“There is considerable personal and public health value in informing infected, but otherwise untested, persons of their true positive HIV status,” FDA staff wrote. “However, this benefit is offset in some measure by HIV-positive individuals who receive an incorrect message that they are not infected.”

OraSure fell 14 percent to $9.65 at 3:15 p.m. New Yorktime, the largest intraday decline in two years.

About 1.2 million people in the U.S. have HIV, the virus that causes AIDS, and 20 percent of those people are unaware they are infected, according to the Centers for Disease Control and Prevention. The test made by Bethlehem, Pennsylvania-based OraSure would be the first of its kind. Other kits, such as Home Access Health Corp.’s Express HIV Test System, require users to anonymously send blood samples to a laboratory for testing.

Clinical Trial Findings

A clinical trial of OraSure’s test identified 100 previously undiagnosed people infected with HIV of 5,800 patients who used the product, according to the company. OraSure markets the only FDA-approved rapid HIV test that detects HIV antibodies in oral fluid and provides results in a clinic or doctor’s office within 20 minutes.

OraQuick would produce one false negative result for every 13 true positive tests, FDA staff said. That would total an estimated 3,800 people with HIV who falsely test negative each year, according to the report. In addition, the test would produce one false positive result for every 3,750 true negative tests resulting in 1,100 people a year who aren’t infected believing they are, the report said.

The false negatives reported were higher than what the FDA considers a “minimum acceptable performance” while the false positives were lower.

‘Confident’ in Test

“We are very confident in the efficacy, safety and performance of the OraQuick In-Home HIV Test, which has been proven to have a calculated accuracy of 99 percent in extensive self-test clinical studies,” Ron Ticho, a spokesman, said in an e-mail.

OraQuick would identify 9,087 previously undiagnosed HIV-positive individuals for each 1 million who use the test, Ticho said.

OraSure doesn’t have an estimate for when the FDA may decide on the home-results test, said Susan Brophy, of Golin Harris, who is a spokeswoman for the company.

The FDA cleared the Home Access test in 1996. Results can be obtained the day a sample arrives at a laboratory and retrieved anonymously using a pin number, according to theHoffman Estates, Illinois-based company. The FDA stresses the benefit of having medical professionals help users interpret the results and understand treatment options on its website.

The FDA staff expressed concern that people who may have gotten tested professionally would turn to the “less sensitive, but more private,” alternative. No studies have been done to test the potential impact, according to the report.

“Counseling, which uses both printed material and telephone interaction, provides the user with an interpretation of the test result,” the FDA said on its website about the Home Access test system.

Counseling also can provide information on preventing transmission of the disease for people who are infected and on treatment options and doctor referrals, the FDA said.

More than 16,000 people with AIDS were estimated to have died in 2008, the CDC said.

To contact the reporter on this story: Anna Edney in Washington at aedney@bloomberg.net.

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net

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