FDA Hearing on Home HIV Testing
Recently, the FDA blood products advisory committee has been considering what the agency should know before approving an over-the-counter (OTC) rapid home test to diagnose HIV infection.
The only approved oral rapid test on the market for use by medical personnel is the OraQuick assay, and although the company has not yet applied to market the test as a home test, the OraQuick product, its routine use in clinics and by non-lab personnel in special projects provided background for the committee's discussion.
At a November 2005 meeting there was universal and enthusiastic agreement by community representatives that any product or strategy that could improve testing rates would be welcomed and that OTC rapid home tests would be a useful addition to current testing options and may contribute to increased awareness of HIV status, which could possibly affect new infection rates. But community representatives -- as well as physicians, industry representatives, and committee members -- all stressed the importance of supporting the home tester with a 24/7 hotline that could provide emotional support and competent referral to care, all with cultural sensitivity and in multiple languages.
Most experts thought that the technical specifications of the OraQuick test, its ability to sensitively detect and discriminate antibodies to HIV without giving too many false positive results or missing true infections, were excellent. The test achieves 99% sensitivity and specificity in controlled studies when used by trained technicians under ideal conditions. What is unknown, however, is how well the test will perform when used by consumers at home.
One of the key challenges posed to the committee was to advise the FDA on what kind of studies would be required to evaluate the effectiveness of the test under real world conditions. This is where the unknowns become formidable. At this point no one can say if the benefits of OTC home testing will outweigh the risks if the quality of the test results inevitably degrades when used by untrained consumers. There was also extensive discussion about the extent of training that can reasonably be offered on a product package, especially when many individuals may not read the instructions.
While the oral HIV test has been proven simple and reliable to use by people with only a few minutes of demonstration and training, home users will not have even that much support. They will need to follow illustrated instructions that require a minimal amount of reading. Any positive result must be confirmed. This fact must be made clear, and explanation of what to do next must be provided.
The correct use of the test brushes the device against the upper and lower gingival surfaces. Then a fluid is applied to the dipstick, and the test result is read after 20 minutes.
But untrained users have been observed to fill the test well with saliva before brushing the proper surface; some have dipped the stick in the fluid before putting it in their mouths; others estimated that 20 minutes had elapsed after only five had. Some may use other body fluids; users may buy one test and share it among several friends. As simple as the test is, all of the creative and incorrect ways the procedure can be performed have not yet been imagined.
There is also a high likelihood that many people would inappropriately use the product as a "morning-after" test, well before any HIV antibodies have developed.
The committee became bogged down in considering a variety of ways to address all of the knowledge that must be imparted for correct test usage. One committee member noted that the package for the test had become unwieldy, stuffed with all the training DVDs, comic books, lists of hotlines, and explanatory materials in multiple languages that had been proposed.
One member recommended keeping the burden on the user light by sticking to clear instructions: a simple explanation of what the test does and does not tell, and a clear set of instructions for what to do if the test is positive. Additional educational material could be provided, but all agreed that users could not be expected to read it.
In the end the committee seemed to agree that there was a need for an OTC rapid home test and that the benefits would likely outweigh the risks, even if the predictive value of the test were degraded by a high rate of invalid results. However, where the cutoff between benefit and harm lies is not known, but it will likely vary considerably depending on the prevalence of HIV in a particular population. Much more study is required.
The hearings also made it clear that clinical trials for the test and the supporting materials with consumers in a real world setting would be a complicated and lengthy process. As much as one may be needed, an OTC rapid test is not likely to be approved soon.
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This article was provided by Gay Men's Health Crisis. It is a part of the publication GMHC Treatment Issues. Visit GMHC's website to find out more about their activities, publications and services.