Rapid HIV testing method approved — prepare now to apply new strategies

New test yields results with 99.6% accuracy in as little as 20 minutes

How many times have you tested patients to determine their HIV status, never to see them return for the test results? Get ready for that scene to change; the Food and Drug Administration’s (FDA) recent approval of a new test designed to detect HIV-1 antibodies in fingerstick whole blood samples will allow you to deliver the results in about 20 minutes.

About 2.1 million HIV tests are conducted each year as part of publicly funded counseling, testing, and referral programs.1 According to Atlanta-based Centers for Disease Control and Prevention’s (CDC) data, 30% of people who tested HIV-positive during 2000 and 39% of persons who tested HIV-negative did not return for their test results.1

The approval of a rapid HIV test has the potential to significantly impact the U.S. epidemic, says Robert Janssen, MD, director of the CDC Division of HIV/AIDS Prevention. The FDA approved the OraQuick Rapid HIV-1 Antibody Test, manufactured by OraSure Technologies of Bethlehem, PA, in November 2002.

"Availability of a rapid test will increase the number of infected people who know their status — a key goal of CDC’s HIV prevention strategic plan — and likely will reduce the number of people who get tested but don’t return for their results," states Janssen.

Shipments on the way

While more than 60 rapid HIV tests have been developed and used in various countries, only two have received approval from the FDA prior to OraQuick: Recombigen HIV-1 LA, which was withdrawn from the U.S. market due to poor performance, and Single-Use Diagnostic System for HIV-1 (or SUDS, marketed by Abbott-Murex, Norcross, GA), which still is available.2 (Contraceptive Tech-nology Update reported on the SUDS test in the June 1998 article, "New guidelines open door for rapid HIV screening," included on p. 1 of the STD Quarterly inserted in the newsletter.)

U.S. public health officials have been interested in bringing more quick, easy-to-use tests to market; the U.S. military, in particular, wants rapid tests to prevent the accidental transfusion of HIV-infected blood on the battlefield.3

At press time, shipments of the new test were scheduled to be under way, according to William Bruckner, OraSure vice president of strategic marketing. The company swung into production soon after the FDA approval. OraSure has entered in a coexclusive agreement with Abbott Park, IL-based Abbott Laboratories to distribute the OraQuick test. Abbott is focusing on hospital and physicians’ office laboratory markets, while OraSure is working with the public health and criminal justice markets where it already maintains a direct sales force.

Pricing for OraQuick is going to be comparable to current lab-based tests, states Bruckner.

"Our intention is to make OraQuick as available as possible to as many certified outlets as possible within the United States," says Bruckner. "We want to get it in the hands of the people where it will do the most good."

Status of CLIA waiver?

The test has been categorized as "moderately complex" under the federal Clinical Laboratory Improvement Amendments of 1988 (CLIA) legislation, which specifies that laboratory requirements be based on the complexity of the test performed. SUDS also is rated as a moderate-complexity rapid HIV test; however, it requires serum or plasma as opposed to fingerstick whole blood for analysis.4

The test’s moderate complexity designation means that the OraQuik test only can be performed in CLIA-approved labs by CLIA-certified laboratory technicians or medical staff. Administration of the CLIA program is handled by the Baltimore-based Centers for Medicare & Medicaid Services. According to OraSure, there are nearly 40,000 qualified locations in the United States certified to perform moderately complex diagnostic tests; an estimated 17 million HIV tests are conducted annually at these locations.

To further broaden OraQuick’s use in the fight against HIV, public health officials, including Health and Human Services Secretary Tommy Thompson, have called for the manufacturer to apply a CLIA waiver for the test. If the waiver is received, OraQuick can be used in such settings as outreach clinics and mobile vans. OraSure has filed a draft protocol with the FDA for the waiver and hopes to complete all necessary documentation in the next few months, Bruckner confirms.

Look at the results

According to data submitted by OraSure for FDA approval, the sensitivity of OraQuick in the clinical studies performed was 99.6% (95% confidence interval [CI] = 98.5%-99.9%), and specificity was 100% (95% CI = 99.7%-100%).4 Such sensitivity and specificity make the test comparable to FDA-approved enzyme immunoassays in widespread use.4

If a negative test result is received, providers can offer those results at the initial visit, and no retesting is required. If the patient has a recent history (within three months) of known or possible exposure to HIV, the CDC recommends retesting since there may have been insufficient time for the development of detectable antibodies. All reactive (preliminary positive) rapid test results should be confirmed by supplemental testing by a Western blot or immunofluorescence assay.5

To perform the OraQuick test, a fingerstick sample of blood is collected and transferred to a vial, where it is mixed with a developing solution. The test device, which resembles a dipstick, is inserted into the vial. If HIV-1 antibodies are present in the solution, the device will display two reddish-purple lines.

For those living with HIV, knowledge of status is critical, but only 75% of those infected in the United States are aware of their infection, says Janssen. Because of the potential public health benefits of rapid HIV testing, the CDC and the Centers for Medicare & Medicaid Services are working with state and other health officials to make the test widely available and offer technical assistance and counseling training for its use.

"The availability of a quick, easy, accurate HIV test will allow broader access to HIV diagnostic testing, help link those already infected to treatment and care services, and will allow those who are uninfected but at risk to avoid infection through prevention services," Janssen states.

References

1. HIV CT Client Record Report, 2000 U.S. Total; CDC, unpublished data. Accessed at: www.cdc.gov/hiv/pubs/rt-counseling.htm#1.

2. Branson BM. Rapid tests for HIV antibody. AIDS Reviews 2000; 2:76-83.

3. Anand G. Why rapid HIV tests, widely sold overseas, have eluded the U.S. Wall Street Journal; Dec. 20, 2001. Accessed at lists.cdcnpin.org/pipermail/prevention-news/2001-December/000045.html.

4. Notice to readers: approval of a new rapid test for HIV antibody. MMWR 2002; 51;1,051-1,052.

5. Centers for Disease Control and Prevention. Revised guidelines for HIV counseling, testing, and referral. MMWR 2001; 50(RR-19):1-58.

Resources

• For more information on the OraQuick Rapid HIV-1 Antibody Test, contact: OraSure, 150 Webster St., Bethlehem, PA 18015. Telephone: (800) ORASURE (672-7873). Web: www.orasure.com.

• Review the Atlanta-based Centers for Disease and Control Prevention’s updated guidelines on HIV testing at its web site: www.cdc.gov/hiv/testing.htm.

• Check out counseling protocol information at the Project Respect-2 web site: www.cdc.gov/hiv/projects/respect-2/default.htm.

• Review the application and state agency contact information for Clinical Laboratory Improvement Amendments of 1988 certification at the Baltimore, MD-based Centers for Medicare & Medicaid Services web site: www.cms.hhs.gov/clia. Information about enrollment and the requirements for moderate-complexity testing are available at www.phppo.cdc.gov/clia/default.asp.