Study: Therapy Completely Clears HPV in One-Third of Cervical Precancers

Authored by labblog.uofmhealth.org and submitted by ekser
image for Study: Therapy Completely Clears HPV in One-Third of Cervical Precancers

A potential new immune-based therapy to treat precancers in the cervix completely eliminated both the lesion and the underlying HPV infection in a third of women enrolled in a clinical trial.

The shot, a therapeutic vaccine, injects a specific protein that triggers an immune system response to attack high-risk HPV types that cause nearly all cervical cancer precursors, known as cervical intraepithelial neoplasia, or CIN.

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“There are very few products trying to cure women who already have an HPV infection,” says Diane Harper, M.D., M.P.H., M.S., professor of family medicine and obstetrics and gynecology at Michigan Medicine. “It’s very exciting. This is the first time we’ve seen something with this success rate that is relatively easy to implement.”

Cervical precancerous lesions are divided into three grades of severity. CIN 1 lesions generally clear up on their own. CIN 2 lesions often clear up on their own, but can also progress to CIN 3 lesions. CIN 3 is the most severe. It’s a very slow-growing disease, though: fewer than half of CIN 3 lesions will have become cancer within 30 years.

“But we have no way to determine which women with CIN 3 will progress to cancer and which women will not. So we treat all women with CIN 2 or 3 as if they are likely to develop cancer,” Harper says.

The study enrolled 192 women diagnosed with CIN2 or CIN3, randomizing 129 to receive the vaccine and 63 to receive a placebo. Women were given three shots in their thigh, one per week for three weeks. Six months later, the women were treated with standard surgical procedures for CIN 2/3 and the removed tissue was examined.

Women who received the vaccine were more than twice as likely as those who received placebo to see their CIN eliminated regardless of the type of HPV infection. The results were most striking in the more-severe CIN3: at least 15 percent and as much as 36 percent of those who got the vaccine saw their CIN3 eliminated, while none of the women in the placebo group did.

MLS_toimpress on April 8th, 2019 at 03:18 UTC »

2 of my 3 best friends have had to have LEEPs to remove precancerous lesions. None of us are yet 30. It would be nice if we could all have more peace of mind knowing that they were less likely to have the lesions return. I wish the number was higher than 36% though.

Altostratus on April 8th, 2019 at 03:02 UTC »

As someone who had a LEEP to remove my grade 3 lesions, this is huge progress! It is a very invasive procedure with risks down the line.

ekser on April 8th, 2019 at 00:02 UTC »

Journal reference: https://www.sciencedirect.com/science/article/pii/S0090825819304846

Abstract Background

While prophylactic human papillomavirus (HPV) vaccination exists, women are still developing cervical intraepithelial neoplasia (CIN) grade 2 or 3 for which an immunotherapeutic, non-surgical, approach may be effective. The primary aim was to assess the efficacy of tipapkinogen sovacivec (TS) vaccine in achieving histologic resolution of CIN2/3 associated with high risk (HR) HPV types.

Methods

Women 18 years and older who had confirmed CIN2/3 were enrolled in a randomized, double blind, placebo-controlled phase II trial and assigned to drug in a 2:1 ratio (vaccine:placebo). The primary endpoint occurred at month 6 when the excisional therapy was performed; cytology and HR HPV typing were performed at months 3, 6 and every six months through month 30. The safety population included all patients who received at least one dose of study drug.

Results

Of the 129 women randomized to vaccine and 63 to placebo, complete resolution was significantly higher in the vaccine group than placebo for CIN 2/3 regardless of the 13 HR HPV types assayed (24% vs. 10%, p < 0.05); as well as for only CIN 3 also regardless of HR HPV type (21% vs. 0%, p < 0.01). Irrespective of baseline HPV infection, viral DNA clearance was higher in the vaccine group compared to placebo (p < 0.01). The vaccine was well tolerated with the most common adverse events being injection site reactions.

Conclusions

The TS vaccine provides histologic clearance of CIN 2/3 irrespective of HR HPV type in one third of subjects and is generally safe through 30 months.