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Over-the-counter OraQuick HIV test: What does this mean for you?

The views expressed are those of the author and are not necessarily those of Scientific American.


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The FDA has just announced approval for the OraQuick In-Home HIV test, by OraSure Technologies. That’s great news on some fronts, but the test raises new questions, as well.

As I’ve just been catching up on my vacation reading with Marya Zilberberg’s helpful new book, “Between the Lines,” the first thing that caught my eye were the statistics on the test’s accuracy. The test had a sensitivity of ~92% compared to in-office testing results of 99%. So one out of every 12 test results would be falsely negative.

Next was the not entirely reassuring plea of one of the FDA advisory committee members, Dr. Brooks Jackson, professor and chair of pathology at Johns Hopkins University Medical School, “We shouldn’t let the perfect be the enemy of the good.”

So, practically speaking, what do these results mean?

Perspective on the problem of HIV

According to the CDC, about 1.2 million people in the U.S. have HIV, the virus that causes AIDS; there are approximately 50,000 new HIV infections each year. Worryingly, 20 percent of HIV-infected people are not even aware that they are infected (26% in Canada). And one-third of those with a new HIV diagnoses progressed to AIDS within 12 months. So there is a strong public health incentive to identifying patients earlier so that they are less likely to transmit the infection to others, and so that they receive earlier treatment.

The long path of HIV testing

Testing has been limited to medical settings—first to hospitals (1980s), where a requirement was pre- and post- test counseling of the patient.

Timeline of rapid HIV-1 testing developmentIn 2002, FDA approved the first CLIA-waived rapid HIV test, which allowed for testing to be done in mobile outreach centers. The FDA looked at a staged approaches to achieving the goal of a home-use test, looking not only at test accuracy, but at test interpretation, and willingness of test subjects to medical follow-up. The first phase looked at test sensitivity and specificity when the test was run by trained personnel. This culminated in the 2004 approval of the OraQuick ADVANCE Rapid HIV-1/2 antibody test on oral fluid. This test showed a 99.3 percent sensitivity and 99.8 percent specificity.

The second phase looked at sensitivity and specificity of untrained users under observation, in 2008. In the Phase 2B Observed use trial, there were 2% of operational errors observed. These errors prevented users from obtaining an HIV test result; revisions were then made to the packaging and labeling instructions. When those results looked promising, with a sensitivity of 97.9% and specificity of 99.79%, the third phase extended testing to the intended-use setting.

Surprisingly, in this final Phase 3 testing, in a more real-world scenario, Specificity was 99.98%, but the sensitivity dropped to 92.9%. OraSure’s briefing document says “Subjects with false negative results were not clustered in any particular site and were not asymmetrically distributed according to race, gender, sexual orientation or measured literacy score…The reasons for these false negative results based on self-reported outcomes of an individual’s self-testing are unknown.”Bottom line: one out of every 12 test results would be falsely negative.

Reviewing the Orasure background materials to the FDA and the staged testing details, I’m impressed with the care and level of detail that went into this product’s development—including not only the actual testing, but tests of label understanding, revisions, and creation of the call center.

Risks and down-sides of HIV home testing

The FDA itself notes a number of negatives: “The potential risks of an HIV home-use test include not fully comprehending the limitations of a screening test, such as misunderstanding a negative result when testing during the window period or the incomplete understanding of a false positive result. Home-use tests lack live counseling, resulting in the potential for adverse outcomes if the user obtains an unexpected result without concurrent live counseling.

Additional risks include the inability to reach individuals for medical follow-up, partner notification, and public health reporting. There is also the potential for coercive testing and testing by unprepared minors.”

One critical decision will be the price point that OraSure sets for their test. Currently priced at $17.50 for clinics, estimates are in the $40-60 range. While that will be good for investors, it’s not so good for patients. In surveys, 46% said they would pay no more than $20 for a test; 13% said they would only take the test if it were free. And undoubtedly many who would benefit from an OTC test will be unable to pay that much several times a year, which is the recommended interval for some high-risk groups. So from a public health perspective, the pricing will be critical as to the test’s impact.

Unintended consequences

A simple home HIV test might pose an unexpected problem for HIV vaccine trials. In a 2010 trial, 42% of vaccine trial participants developed antibodies to the vaccine, and these antibodies cross-reacted  with the test, causing them to be falsely positive. Clinical trial participants could readily detect if they received the vaccine or not by these results.

Benefits of OraQuick

Because this new test can be done in private, at home, it is hoped that more people will be tested. Importantly, 41% of Phase 3 study participants found to be HIV positive reported they had never before been tested; many indicated they would not have been tested without the OTC self-testing option. Projections are that in a million tests, 9,087 additional HIV positive individuals would be identified, who would have been missed by traditional testing methods.

I’m concerned about the relatively low sensitivity, but looking at projections, the approval now makes more sense from a public health perspective. It comes down to the risk/benefit for the individual vs. the community as a whole. For the individual who receives the 1/12 false negative result, the test has the potential to be quite harmful. They might indulge in riskier behaviors and put their partners at additional risk. But for the ~9,000/million who are identified as HIV positive, and for their partners, this test is extraordinarily beneficial, enabling earlier treatment. The test is also projected to prevent 700 additional HIV transmissions per million people. So the FDA concluded that if just 1% of Americans uses the test, OraQuick could identify up to 45,000 previously undetected HIV-positive people and prevent around 4,000 new infections each year. I wonder if anyone has calculated yet the breakpoint where providing the test for free (or perhaps on a sliding scale) would be a cost-effective strategy. I hope OraQuick will be priced to have the greatest public health impact.

Home testing kits have long been available for pregnancy tests. OraQuick is exciting as the the first OTC, in home test for an infectious disease. Its impact? That will depend on the cost, public outreach and education, and how well can directions be followed by individuals who are poorly literate or have impaired ability to understand.

Credits:

Photo of OraQuick testing: Marcello Casal JR/ABr; Agência Brasil

Timeline of test development:  www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/BloodVaccinesandOtherBiologics/BloodProductsAdvisoryCommittee/UCM303652.pdf

“Molecules to Medicine” banner © Michelle Banks

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Judy Stone About the Author: Judy Stone, MD is an infectious disease specialist, experienced in conducting clinical research. She is the author of Conducting Clinical Research, the essential guide to the topic. She survived 25 years in solo practice in rural Cumberland, Maryland, and is now broadening her horizons. She particularly loves writing about ethical issues, and tilting at windmills in her advocacy for social justice. As part of her overall desire to save the world when she grows up, she has become especially interested in neglected tropical diseases. When not slaving over hot patients, she can be found playing with photography, friends’ dogs, or in her garden. Follow on Twitter @drjudystone or on her website. Follow on Twitter @drjudystone.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. wendysueswanson 7:35 pm 07/9/2012

    Thanks for this report.

    As a pediatrician, I expect this to cause confusion for my adolescent patients, however, I see tests like this as the future of health care.

    Home testing is ideal only if a patient has access & counsel from their primary care doctor in near real time–something that exists currently only for the v wealthy in concierge type practices. Imagine if my teen patients could text me w their questions? In the situation of a positive test, I could text them next steps and partner with them to grant them clarity, provide education, and help them protect themselves & their partners.

    When reimbursement models change in health care and we value physician time for communication, we will see the rise of this type of testing. My hope is that this could transform public health preventative efforts.

    The future of affordable health care demands the progression of science to include miraculous home testing like this. But it also demands far improved, timely communication with experts for sincere partnerships.

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  2. 2. Judy Stone in reply to Judy Stone 8:49 pm 07/9/2012

    Thank you. I largely agree with you, and can relate. Infectious diseases does not get reimbursed for reviewing Gram stains, x-rays, arranging home IV antibiotics, monitoring for drug toxicity, or counseling our patients (HIV or other), either. I’m not sure I would want my patients texting me for an instantaneous reply whenever they want, however.

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  3. 3. timbo555 10:43 pm 07/9/2012

    What does this mean for me? Do you mean me personally? Well, pardon me for being frank here, but it doesn’t mean much for me. This is because I don’t engage in indescriminant anal sex with multiple partners. Nor do I self administer IV drugs with used needles. This started out as, and for the most part remains a behaviorally spread disease. The cure for AIDS is to not get it in the first place. There are very few real victims.

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  4. 4. Judy Stone in reply to Judy Stone 7:15 am 07/10/2012

    Actually, a number of the patients I see are women who acquire infection from philandering husbands. Used to see transfusion related cases. There are multiple factors. Early diagnosis is a valuable tool not only for the individual patient, but to prevent transmission to others.

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  5. 5. timbo555 1:30 am 07/11/2012

    I was in a “Sex in Sobriety” workshop a year or so ago after a speaker gave his talk we broke out into five circles of fifteen men each. It’s single greates therapeutic value was for men to have a safe place, a container, if you will to dump their sexual baggage.

    A young man raised his hand and said, “I have Aids.” I was a little unprepared for that, and asked:”Do you use a condom”? He said, “sometimes.” A little alarmed, I asked, “Do you tell your partners”? He said, “When I use a condom I do.”

    I read recently The leading cause of death in America for African American women in their 30′s is Aids. I misspoke above. There are plenty of victims….

    Link to this
  6. 6. aidel 6:32 am 07/20/2012

    timbo555, if only life could be so simple! The fact, however, is that life, human behavior, and the reality of disease are far more complicated. Ever have diarrhea? Well, that’s probably because your hand-washing is inadequate.

    Link to this
  7. 7. tipuasher 8:09 am 09/4/2012

    HIV eventually develops into AIDS, unless treated with antiviral drugs. AIDS causes the body’s immune system to breakdown, leading to infections which become fatal.

    Link to this

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