Immune-based biomarker accurately predicts response to imiquimod immunotherapy in cervical high-grade squamous intraepithelial lesions

Vaginal Microbiota and Local Immunity in HPV-Induced High-Grade Cervical Dysplasia: A Narrative Review

Persistent high-risk Human Papillomavirus infection is the primary factor in cervical carcinogenesis. However, other host-related features are believed to play a role as well. Recent research suggests that the vaginal microbiome and the immune microenvironment play a significant role in the acquisition and persistence of Human Papillomavirus infection, as well as in the regression or progression of cervical intraepithelial lesions. Studies in this emerging field describe factors associated with this interaction, though the precise nature remains incompletely understood. In this narrative review, we aim to summarize the current literature on the topic and propose hypotheses and recommendations for future research and treatment strategies.

Imiquimod Is Effective in Reducing Cervical Intraepithelial Neoplasia: A Systematic Review and Meta-Analysis

INTRODUCTION

Topical Imiquimod is an immune response modifier approved for the off-label use of vulvar intraepithelial neoplasia. We conducted this systematic review and meta-analysis to investigate the efficacy and safety of Imiquimod in treating cervical intraepithelial neoplasia (CIN) and human papillomavirus (HPV)-positive patients.

METHODS

The study was prospectively registered (CRD420222870) and involved a comprehensive systematic search of five medical databases on 10 October 2022. We included articles that assessed the use of Imiquimod in cervical dysplasia and HPV-positive patients. Pooled proportions, risk ratios (RRs), and corresponding 95% confidence intervals (CIs) were calculated using a random effects model to generate summary estimates. Statistical heterogeneity was assessed using I2 tested by the Cochran Q tests.

RESULTS

Eight articles reported on 398 patients who received Imiquimod out of 672 patients. Among CIN-2-3 patients, we observed a pooled regression rate of 61% (CI: 0.46-0.75; I2: 77%). When compared, Imiquimod was inferior to conization (RR: 0.62; CI: 0.42-0.92; I2: 64%). The HPV clearance rate in women who completed Imiquimod treatment was 60% (CI: 0.31-0.81; I2: 57%). The majority of side effects reported were mild to moderate in severity.

CONCLUSIONS

Our findings indicate that topical Imiquimod is safe and effective in reducing cervical intraepithelial neoplasia and promoting HPV clearance. However, it was found to be inferior compared to conization. Imiquimod could be considered a potential medication for high-grade CIN patients and should be incorporated into guidelines for treating cervical dysplasia.

Topical imiquimod treatment of residual or recurrent cervical intraepithelial neoplasia lesions (TOPIC-2): A randomised controlled trial

OBJECTIVE

To investigate the efficacy of imiquimod in women with residual or recurrent cervical intraepithelial neoplasia (rrCIN), compared with large loop excision of the transformation zone (LLETZ).

DESIGN

Randomised controlled non-inferiority trial.

SETTING

One academic and one regional hospital in the Netherlands.

POPULATION

Thirty-five women with rrCIN were included in the study between May 2016 and May 2021.

METHODS

Women were randomised to receive treatment with 5% imiquimod cream (12.5 mg) intravaginally (three times a week for a duration of 16 weeks) or a LLETZ procedure (standard treatment).

MAIN OUTCOME MEASURES

The primary outcome was reduction to normal cytology at 6 months after starting treatment. Secondary outcomes were clearance of high-risk human papilloma virus (hr-HPV) in both groups and reduction to ≤CIN1 in the imiquimod group. Side effects were monitored.

RESULTS

Treatment success was 33% (6/18) in the imiquimod group versus 100% (16/16) in the LLETZ group (P < 0.001), whereas HPV clearance was 22% (4/18) in the imiquimod group versus 88% (14/16) in the LLETZ group (P < 0.001). After the randomisation of 35 women, the futility of treatment with imiquimod was proven and the trial was prematurely finished. In the follow-up period, three patients remained without additional treatment, whereas all other patients underwent LLETZ, conisation or hysterectomy. In the LLETZ group none of the patients received additional treatment during 2 years of follow-up.

CONCLUSIONS

This is the first randomised controlled trial to show that topical imiquimod has a significantly lower success rate in terms of reduction to normal cytology and hr-HPV clearance, compared with LLETZ, in women with rrCIN. Additionally, imiquimod has numerous side effects and after using imiquimod most women with rrCIN still required additional surgical treatment.

Modulation of sHLA-G, PD-1, and PD-L1 Expression in Cervical Lesions Following Imiquimod Treatment and Its Association with Treatment Success

(1) Background: Cervical intraepithelial neoplasia (CIN) is a precancerous condition linked to human papillomavirus (HPV) infection, often necessitating surgical interventions carrying the risk of subsequent preterm births. This study explores the potential of imiquimod (IMQ), as a non-invasive alternative treatment. The focus is on understanding IMQ impact on immune checkpoint molecules, particularly PD-1, PD-L1, and sHLA-G, which play pivotal roles in shaping immune responses and cancer progression. (2) Methods: Forty-three patients diagnosed with a high-risk squamous intraepithelial lesion (HSIL, p16-positive) self-applied 5% IMQ encapsulated in sachets containing 250 g of cream into the vaginal cavity three times a week for 16 weeks. The impact of IMQ therapy on cervical lesion regression was assessed through immunohistochemistry (IHC), examining changes in sHLA-G, PD-L1, and PD-1 levels. The antiviral activity of IMQ was evaluated through HPV-E7 immunofluorescence. Ethical considerations were adhered to, and the research methods were based on a previously approved clinical trial (clinicaltrials.gov Identifier: NCT04859361). (3) Results: IMQ treatment demonstrated efficacy, leading to lesion regression. sHLA-G levels in CIN before starting IMQ application were associated with unsuccessful treatment (p = 0.0036). IMQ did not significantly alter the expression of PD-1. We observed a decrease in PD-L1 levels in those who were successfully treated (p = 0.0509) and a reduction in HPV burden. (4) Conclusions: IMQ exhibits promise as a non-invasive treatment for CIN, emphasising its potential to modulate the immune microenvironment. Baseline sHLA-G levels emerge as potential predictors of treatment response. Understanding the nuanced dynamics of immune checkpoints sheds light on IMQ mechanism of action. Further exploration is warranted to decipher the intricate mechanisms underlying IMQ treatment in the context of cervical lesions.

The efficacy of topical imiquimod in high-grade cervical intraepithelial neoplasia: A systematic review and meta-analysis

OBJECTIVE

A major side effect of cervical excision for high-grade cervical intraepithelial neoplasia (CIN) is premature birth. A non-invasive treatment for reproductive age women is warranted. The aim of the present study was to determine the efficacy of topical imiquimod in the treatment of high-grade CIN, defined as a regression to ≤CIN 1, and to determine the clearance rate of high-risk human papillomavirus (hr-HPV), compared with surgical treatment and placebo.

METHODS

Databases were searched for articles from their inception to February 2023.The study protocol number was INPLASY2022110046. Original studies reporting the efficacy of topical imiquimod in CIN 2, CIN 3 or persistent hr-HPV infections were included. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses checklist.

RESULTS

Five studies were included (n = 463). Histological regression to ≤CIN 1 was 55% in imiquimod versus 29% in placebo, and 93% in surgical treatment. Imiquimod-treated women had a greater odds of histological regression to ≤CIN 1 than placebo (odds ratio [OR] 4.17, 95% confidence interval [CI] 2.03-8.54). In comparison to imiquimod, surgical treatment had an OR of 14.81(95% CI 6.59-33.27) for histological regression to ≤CIN 1. The hr-HPV clearance rate was 53.4% after imiquimod and 66% after surgical treatment (95% CI 0.62-23.77).

CONCLUSIONS

The histological regression rate is highest for surgical treatment followed by imiquimod treatment and placebo.

Recent advances in treating female genital human papillomavirus related neoplasms with topical imiquimod

Human papillomavirus (HPV) encompasses a group of viruses that infect the skin and mucous membranes. In the presence of certain factors, persistent infection with high-risk HPVs can trigger a process of neoplastic transformation. Imiquimod is a topical agent that acts as a Toll-like receptor 7/8 agonist, stimulating the innate and adaptive immune system to exert antitumor and antiviral effects. It has been approved for the treatment of various skin conditions, however, its efficacy and safety in the management of HPV-related-neoplasms of the lower genital tract, such as vulvar, vaginal, and cervical neoplasia, are still under investigation. This review summarizes the current evidence on the use of imiquimod for the treatment of HPV-induced lesions of the female lower genital tract, focusing on its indications, mechanisms of action, outcomes, and predictors of response.