Over The Counter HIV TestingA Technology Whose Time has Come

Freya Spielberg, MD MPHFreya@u.washington.edu

My Background

Assistant Professor of Family Medicine, University of Washington

Researcher in Center For AIDS and STDs

15 Years Research Experience in Alternative HIV Counseling and Testing Strategies

Test developmentAcceptabilityEffectivenessCost

First study of self-testing for HIV (n=240)

Need>1 Million currently infected with HIV 40,000 new HIV infections in the US

every year (CDC, 2004)

>250,000 of those infected unaware of their status (25-33% of all positives) (CDC,

2003;CDC, 2001)

30% of positives, 40% negatives don’t return for standard antibody test results

Knowledge of HIV infection decreases behavior that can result in HIV transmission (Liddicoat et al., 2004)

Why an OTC Rapid Test Preferable - Studies have shown self-testing is

preferable to people at risk who have never tested (Spielberg JAIDS 2003)

Better Access - Self-testing is 25 times more acceptable than home specimen collection, so access to acceptable testing would be substantially improved (Spielberg JAIDS 2003)

Overcoming stigma - People with stigma who avoid clinics may be more likely to test.

Likely safe - Post-Marketing studies of home specimen collection showed that the vast majority of people with positive test results accepted referrals or were already in care. (Branson JAMA 1998) No studies have shown increased risk of suicide with HIV testing.

Questions to be Answered Can people perform the test accurately?

Will people understand the meaning of their test results? (preliminary, need for confirmation)

Will people who positive results follow up for counseling, confirmation, and medical care.

What type of education/counseling will be necessary to ensure accuracy, safety and follow up for confirmatory testing. Pre-test counseling – Brochure vs. Computer

Post-test counseling – 24 hour telephone counseling

How much will people be willing to pay?

Preliminary Study of Self-TestingStudy of 240 people with HIV

Tests performed with written instructions

Difficulties observed, revisions to instructions made for 7 waves of n=20

Accuracy evaluated with final instructions N=100

Preferences assessed N=240

Willingness to pay assessed N=240

Accuracy of Self-Tests (N=100)

Compared to Staff

Finger-Stick Oral Fluid

False Negative*

5 6

True Positive

84 85

Invalid** 11 9

* HAART increases false negative rates** Invalids due to inability to get FS specimen

or not putting device into diluent.

Preferences (N=240)

Preferences Home Clinic

Location 61% 37%

Privacy 73% 6%

Convenience 76% 10%

Comfortable 70% 10%

Safety 48% 21%

Accuracy 22% 43%

Willingness to Pay For Self-Test:

Cost Finger-stick Oral Fluid

$5 87% 89%

$10 85% 87%

$15 70% 69%

$20 37% 43%

$30 13% 19%

Clinical Trial ConsiderationsRecruit from populations where

marketing is planned (drugstores, internet, high-risk outreach venues).

How sensitive does an OTC test need to be for the benefit to outweigh the risk? Benefit - Number of HIV positive people

learning their status who would not have tested without an OTC test

Risk – If lower sensitivity, number positive people who would have tested at a clinic but instead used an OTC test

Clinical Trial Considerations With sensitivity > 80 % the benefits of an

OTC HIV test would outweigh the risks if for every one first-time tester who tested positive using an OTC < 5 people with HIV switched from clinic-based testing to OTC.

Conservatively assuming that >25% (HSC 49%, Branson, JAMA 1998) of the testers will be first-time testers, there will likely be a ratio of 1 new tester : < 4-5 switchers.

In the least favorable circumstances OTC sensitivity was 94% so it is likely that the benefits will outweigh the risks for an OTC rapid HIV test.

Clinical Trial ConsiderationsPost Marketing Studies - Conduct

post-marketing studies to determine actual uptake among those who have never tested vs. switchers, safety, post-test behaviors and follow up for care. Integrate into existing CDC

National Behavioral Surveillance

Conduct a follow up assessment of a subset of customers

SummaryConcerns about the risks of self-testing

remain unproven.

The benefits of an over-the-counter HIV test very likely outweigh the risks.

FDA should move forward quickly to encourage clinical trials for an OTC rapid HIV test.

Short of a vaccine, a widely accessible inexpensive OTC HIV test is the only intervention currently available that could feasibly change the course of the epidemic.

Fast-track the approval - There is no time to waste.