HPV16 vaccine shows promise in treating precancerous cervical lesions

HPV16 vaccine shows promise in treating precancerous cervical lesions

A therapeutic vaccine targeting human papillomavirus type 16 (HPV16) induced regression in high-grade precancerous neck lesions, according to results of a phase II clinical trial published inClinical cancer researcha journal of the American Association for Cancer Research.

Almost all premalignant cervical lesions and cervical cancers are caused by HPV infection, with HPV16 being involved in most cases. “

Refika Yigit, MD, principal investigator and oncologic gynecologist at University Medical Center Groningen, The Netherlands

In individuals with grade 3 cervical intraepithelial neoplasia (CIN3), the cells are already on the path to malignancy. If left untreated, about a third of these cases progress to cervical cancer within 10 years and about half within 30 years, Yigit explained.

“The main purpose of our study was to investigate whether our therapeutic vaccine - VVAX001 - could provide a potential alternative treatment to excision for the care-care loop, which is often associated with complications,” Yigit added.

The VVAX001 vaccine is a modified version of the Semliki forest virus that does not replicate and produces the oncogenic E6 and E7 proteins that are exclusively expressed by HPV16-infected cells.

In the phase II study, 18 patients with HPV16-positive CIN3 received three doses of VVAX001 three weeks apart and were then routinely monitored via colposcopy before a definitive colposcopic biopsy at 19 weeks post-immunization.

Nine of the 18 patients had regression measurement to low-grade dysplasia and three with complete regressions and no evidence of dysplasia. Lesion size was significantly reduced in all but one of the patients, and these reductions were evident within one month of completion of vaccination. The nine patients whose disease did not resolve received grinding excision surgery, although no residual disease was found in four of these patients, suggesting that the additional time for surgery may have allowed for complete lesion eradication, the authors said.

“To our knowledge, this response rate makes VVAX001 one of the most effective therapeutic vaccines for HPV16-associated CIN3 lesions reported to date,” Yigit said. “If confirmed in a larger study, our results could mean that at least half of patients with CIN3 may be able to skip surgery and avoid all possible side effects and complications.”

From a care perspective, HPV clearance is associated with a lower risk of recurrence, and Yigit said her team expects the same here. Ten of the 16 patients evaluated HPV16, including all nine individuals with past illness. Two patients whose disease did not resolve also resolved HPV16; However, their lesions harbored other HPV strains.

After a median follow-up of 20 months, none of the patients had recurrences.

Limitations of the study include limited follow-up time, small sample size, and lack of a control group for spontaneous regression due to ethical concerns.

This study was supported by the Dutch Cancer Society (KWF) and Vicinivax. Yigit declares no conflict of interest.

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