A U.S. Food and Drug Administration (FDA) panel of 13 members has voted unanimously to replace the common Pap smear test with a specific human papillomavirus (HPV) test as the standard of care for American women.
The panel approved the use of Swiss-based drugmaker Roche’s cobas viral DNA test for HPV. Currently, the test is used as a follow-up for women over 21 who have abnormal Pap test results. It’s also used in conjunction with the Pap smear to detect HPV16 and HPV18 strains in women ages 30 to 65. The HPV16 and 18 strains are considered high-risk and commonly linked to cancerous tumors.
The cobas test screens for a dozen other high-risk HPV stains as well. Roche advised in their FDA proposal that women over 25 who positively screen for HPV16 or 18 should then have a colposcopy to further investigate their cancer risk. Women who did not have those strains but had other types of HPV could then have a Pap test to determine if a colposcopy was needed.
The panel reviewed data from the ATHENA HPV Study, which studied 47,000 women at high risk of developing cervical cancer. The results showed that Roche's test was effective for detecting signs of cervical cancer in these patients.
Is the FDA Playing Monopoly?
Will Roche now have a monopoly on HPV testing in the U.S.? The FDA hasn’t yet approved the panel’s suggestions, but if they do, Roche stands to make a hefty profit. The cobas test is nothing new, but the FDA turning away from Pap testing to HPV testing as a primary screening tool is.
"There are multiple tests out that currently screen for high risk HPV strains,” said Dr. Shefali Patel-Shusterman, a gynecologist based in New Jersey. She believes that other tests like the cobas will emerge to compete.
She added that some tests screen individually for HPV16 and 18 and then classify the other strains as high-risk non-16/18HPV. Those are not the only potentially harmful strains, however. Other labs are also now looking at E6/E7 mRNA in women who test positive for high-risk non-16/18HPV. “This test picks up strains that are considered more virulent,” she said.
The FDA panel's recommendation is for the cobas HPV test to be used as the first-line cervical cancer screening test.
“How to best incorporate HPV-testing into cervical cancer screening has been an ongoing area of discussion,” said Dr. Rhoda Sperling, a professor in the department of obstetrics, gynecology, and reproductive science at Icahn School of Medicine at Mt. Sinai Hospital. Sperling said that current guidelines say cytology—a Pap test—should be the primary screening method.
“What is exciting about the data presented by Roche to the FDA is not the uniqueness of the cobas HPV test but the findings from the ATHENA study, which strongly supports a new approach to screening for high-grade cervical dysplasia/cervical cancer that relies on HPV testing as the first line screen rather than Pap smear cytology,” Sperling said.
No More Pap Smears? Not So Fast
Anecdotally, many women share a dislike of Pap smear tests and may avoid going for an annual gynecological exam because the Pap is uncomfortable. With a new testing standard in place, this could change.
Patel said she is not sure that more women will get screened if the cobas becomes the recommended primary test, but she is sure that other competitors will soon try to gain FDA approval for their own HPV tests.
As it stands right now, most OB/GYNs perform “contesting,” which means they test for HPV with a Pap or perform an HPV test as a follow-up to an abnormal Pap, depending on the patient’s age, Patel said.
Almost half new cases of cervical cancer are diagnosed in women who have never had any screening test, which means that it wasn't because HPV was not detected using existing screening tests, but rather because the patient chose not to be tested, Patel said.
“I think in the short term, even if the FDA adopts the recommendation, most gynecologists will continue with contesting,” Patel said. “This allows us to see who is at risk by being high risk HPV positive, but also allows us to pick up dysplasia and treat those lesions so they do not progress to cervical cancer."