Faster, Easier but Less Precise HIV Test Approved

A test for the human immunodeficiency virus that takes five minutes and can be performed without sophisticated equipment was approved Tuesday by the Food and Drug Administration.

The new test, called Recombigen HIV-1 Latex Agglutination Test, uses an engineered protein and microscopic beads to detect antibodies to the virus that causes AIDS. The test costs about $10 and is designed for use only under supervision of medical professionals.

“This technical advance should help make testing available to all who want to be tested,” FDA Commissioner Frank E. Young said. “It will also be particularly useful in remote areas of the world that lack the facilities for earlier approved tests.”

The test may also be useful, he said, “as a preliminary screening measure in emergency situations in this country.”

Young said the test is not designed to replace the more accurate enzyme-linked immunosorbent assay, or ELISA, now used to screen donated blood. The Recombigen and ELISA tests require a confirming test called the Western Blot because of possible false-positive results.

Recombigen consists of microscopic latex beads coated with an engineered protein taken from the outer HIV surface. The protein is produced by inserting part of the virus’ genetic material into the genes of a bacterium. The bacterium then produces the HIV protein. The protein is refined and then applied to the surface of the beads.

To conduct the test, a sample of blood is mixed with the coated beads. Within five minutes, any HIV antibodies in the blood sample will form clumps, a process called agglutination. This clumping then can be detected by a medical professional under a strong light.

The test is faster than ELISA and Western Blot, which take several hours and require sophisticated laboratory equipment.

An FDA announcement said false-positive reactions can occur in the test “because of interpretation errors, some medical conditions and problems of sample quality that do not ordinarily affect the ELISA test.”