FDA advisory panel backs HPV test as Pap smear adjunct: Approval sought for general cervical cancer screening in women aged 30 years and older. (Identifies High-Risk HPV Strains).

GAITHERSBURG, MD. -- A Food and Drug Administration advisory panel conditionally backed a human papillomavirus test as a routine adjunct to Pap smears in an effort to refine screening for cervical cancer.

The Microbiology Devices Panel recommended by a 6-2 vote that the agency approve the DNA Pap test for general screening in conjunction with a Pap smear in women aged 30 years and older. The test can detect 13 human papillomavirus (HPV) DNA types in cervical specimens. The test's manufacturer, Gaithersburg, Md.-based Digene Corp., already markets its Hybrid Capture 2 test for use in women whose Pap smears are equivocal.

The rationale behind the DNA Pap test is that women with certain HPV strains are at an increased risk of developing cervical cancer. Women who have a negative Pap smear result but are positive for one of the high-risk HPV strains can be followed more closely, allowing for earlier intervention, advocates for the company said.

Conversely, they said, women who have a negative Pap test result but do not have a high-risk HPV strain would be given an added level of reassurance that they are also at low risk for developing cervical cancer.

At the hearing, proponents of the DNA Pap test said that it resulted in a 25% increase in sensitivity to HPV, compared with Pap smears alone. The test also resulted in a 10% decrease in specificity; but that level is acceptable, said Attila Lorincz, Ph.D., Digene's senior vice president and chief scientific officer.

Digene presented eight studies supporting its application. In one of the studies, 1,997 Chinese women aged 35-45 years were screened for cervical intraepithelial neoplasia (CIN) 2 or higher using a variety of methods. All subjects with at least GIN 2 had either a ThinPrep Pap finding of atypical squamous cells of undetermined significance (ASCUS) or above, or a positive HPV test. The HPV test was 95% sensitive in detecting GIN 2 or greater, compared with 94% for the ThinPrep Pap smear and 81% for colposcopy. Specificity was 85% for the HPV test, 78% for the ThinPrep Pap, and 77% for colposcopy.

Although most of the public witnesses at the hearing spoke in favor of the test, the American College of Obstetricians and Gynecologists dissented. "At this time, it doesn't appear that HPV testing is clinically useful," said Mary Mitchell, ACOG's director of clinical practice/gynecology She noted that ACOG's Committee on Gynecologic Practice is currently reevaluating the college's position on the HPV test.