Higher oral HPV16 viral load predicts persistent infection

A higher oral HPV16 DNA viral load was strongly associated with long-term infection in patients with and without HIV, according to data from the POPS study.

“Over half of oral HPV16 infections in the highest tertile of viral load persisted at least 24 months,” researchers wrote in The Journal of Infectious Diseases. “Oral HPV viral load therefore warrants further investigation as a biomarker for longer-term persistence and risk of HPV16-positive oropharyngeal cancer.”

Researchers, including Maura L. Gillison, MD, PhD, of The Ohio State University Comprehensive Cancer Center, identified 88 adult participants in the Persistent Oral Papillomavirus Study (POPS), which comprises two prospective, multicenter cohort studies of HIV-infected and at-risk HIV–uninfected individuals in the United States. All participants had oral HPV infection. The researchers collected oral samples every 6 months, and PCR was used to detect 37 types of HPV DNA, including HPV16. Patients were followed every 6 months for a maximum of 4 years.

The researchers found a significant association between oral HPV16 viral load at the first positive test and time to infection clearance (continuous P-trends < .01). There were higher clearance rates for oral HPV16 infections in the lower tertiles of viral load (log-rank P < .001). The estimated 12-month clearance rate for the highest HPV16 viral load tertile was 26% (95% CI, 12%-44%); for the intermediate tertile, it was 67% (95% CI, 50%-82%); and for the lowest tertile, the clearance rate was 83% (95% CI, 65%-94%).

Clearance rates by 24 months were 41% in the highest viral load tertile vs. 94% in the lowest tertile (P = .03).

“Further investigation is necessary to better understand oral HPV16 viral load’s role in the natural history of oral HPV infection and the risk of clinical progression, particularly in HIV-uninfected individuals,” Gillison and colleagues wrote. – by Jen Byrne

Disclosure: Gillison reports being a consultant for GlaxoSmithKline and Merck. Please see the full study for a list of all other authors’ relevant financial disclosures.