Imiquimod for anogenital warts in non-immunocompromised adults

Current and future direction in treatment of HPV-related cervical disease

Human papillomavirus (HPV) is the most common sexually transmitted virus in the world. About 70% of cervical cancers are caused by the most oncogenic HPV genotypes of 16 and 18. Since available prophylactic vaccines do not induce immunity in those with established HPV infections, the development of therapeutic HPV vaccines using E6 and E7 oncogenes, or both as the target antigens remains essential. Also, knocking out the E6 and E7 oncogenes in host genome by genome-editing CRISPR/Cas system can result in tumor growth suppression. These methods have shown promising results in both preclinical and clinical trials and can be used for controlling the progression of HPV-related cervical diseases. This comprehensive review will detail the current treatment of HPV-related cervical precancerous and cancerous diseases. We also reviewed the future direction of treatment including different kinds of therapeutic methods and vaccines, genome-editing CRISPR/Cas system being studied in clinical trials. Although the progress in the development of therapeutic HPV vaccine has been slow, encouraging results from recent trials showed vaccine-induced regression in high-grade CIN lesions. CRISPR/Cas genome-editing system is also a promising strategy for HPV cancer therapy. However, its safety and specificity need to be optimized before it is used in clinical setting.

Imiquimod versus podophyllotoxin, with and without human papillomavirus vaccine, for anogenital warts: the HIPvac factorial RCT

BACKGROUND

The comparative efficacy, and cost-effectiveness, of imiquimod or podophyllotoxin cream, either alone or in combination with the quadrivalent HPV vaccine (Gardasil^®, Merck Sharp & Dohme Corp., Merck & Co., Inc., Whitehouse Station, NJ, USA) in the treatment and prevention of recurrence of anogenital warts is not known.

OBJECTIVE

The objective was to compare the efficacy of imiquimod and podophyllotoxin creams to treat anogenital warts and to assess whether or not the addition of quadrivalent human papillomavirus vaccine increases wart clearance or prevention of recurrence.

DESIGN

A randomised, controlled, multicentre, partially blinded factorial trial. Participants were randomised equally to four groups, combining either topical treatment with quadrivalent human papillomavirus vaccine or placebo. Randomisation was stratified by gender, a history of previous warts and human immunodeficiency virus status. There was an accompanying economic evaluation, conducted from the provider perspective over the trial duration.

SETTING

The setting was 22 sexual health clinics in England and Wales.

PARTICIPANTS

Participants were patients with a first or repeat episode of anogenital warts who had not been treated in the previous 3 months and had not previously received quadrivalent human papillomavirus vaccine.

INTERVENTIONS

Participants were randomised to 5% imiquimod cream (Aldara^®; Meda Pharmaceuticals, Takeley, UK) for up to 16 weeks or 0.15% podophyllotoxin cream (Warticon^®; GlaxoSmithKlein plc, Brentford, UK) for 4 weeks, which was extended to up to 16 weeks if warts persisted. Participants were simultaneously randomised to quadrivalent human papillomavirus vaccine (Gardasil) or saline control at 0, 8 and 24 weeks. Cryotherapy was permitted after week 4 at the discretion of the investigator.

MAIN OUTCOME MEASURES

The main outcome measures were a combined primary outcome of wart clearance at week 16 and remaining wart free at week 48. Efficacy analysis was by logistic regression with multiple imputation for missing follow-up values; economic evaluation considered the costs per quality-adjusted life-year.

RESULTS

A total of 503 participants were enrolled and attended at least one follow-up visit. The mean age was 31 years, 66% of participants were male (24% of males were men who have sex with men), 50% had a previous history of warts and 2% were living with human immunodeficiency virus. For the primary outcome, the adjusted odds ratio for imiquimod cream versus podophyllotoxin cream was 0.81 (95% confidence interval 0.54 to 1.23), and for quadrivalent human papillomavirus vaccine versus placebo, the adjusted odds ratio was 1.46 (95% confidence interval 0.97 to 2.20). For the components of the primary outcome, the adjusted odds ratio for wart free at week 16 for imiquimod versus podophyllotoxin was 0.77 (95% confidence interval 0.52 to 1.14) and for quadrivalent human papillomavirus vaccine versus placebo was 1.30 (95% confidence interval 0.89 to 1.91). The adjusted odds ratio for remaining wart free at 48 weeks (in those who were wart free at week 16) for imiquimod versus podophyllotoxin was 0.98 (95% confidence interval 0.54 to 1.78) and for quadrivalent human papillomavirus vaccine versus placebo was 1.39 (95% confidence interval 0.73 to 2.63). Podophyllotoxin plus quadrivalent human papillomavirus vaccine had inconclusive cost-effectiveness compared with podophyllotoxin alone.

LIMITATIONS

Hepatitis A vaccine as control was replaced by a saline placebo in a non-identical syringe, administered by someone outside the research team, for logistical reasons. Sample size was reduced from 1000 to 500 because of slow recruitment and other delays.

CONCLUSIONS

A benefit of the vaccine was not demonstrated in this trial. The odds of clearance at week 16 and remaining clear at week 48 were 46% higher with vaccine, and consistent effects were seen for both wart clearance and recurrence separately, but these differences were not statistically significant. Imiquimod and podophyllotoxin creams had similar efficacy for wart clearance, but with a wide confidence interval. The trial results do not support earlier evidence of a lower recurrence with use of imiquimod than with use of podophyllotoxin. Podophyllotoxin without quadrivalent human papillomavirus vaccine is the most cost-effective strategy at the current vaccine list price. A further larger trial is needed to definitively investigate the effect of the vaccine; studies of the immune response in vaccine recipients are needed to investigate the mechanism of action.

TRIAL REGISTRATION

Current Controlled Trials. Current Controlled Trials ISRCTN32729817 and EudraCT 2013-002951-14.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 47. See the NIHR Journals Library website for further project information.

Topical therapies for the treatment of cervical intraepithelial neoplasia (CIN) 2-3: A narrative review

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CIN management is currently surveillance or surgical therapy. This review describes current research on medical therapies.

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Imiquimod is the most studied with evidence of safety and efficacy.

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5-Fluorouracil has also shown promise with two clinical trials showing efficacy as adjuvant and primary treatment.

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Antivirals therapies have produced mixed results with cidofovir showing the most potential.

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The data remains weak regarding hormonal, herbal and alternative therapies rending it difficult to draw conclusions.

Current management of Cervical Intraepithelial Neoplasia (CIN), caused by high-risk human papillomavirus (hr-HPV), is based on surveillance and surgical therapy. Procedures carry potential risks such as preterm birth, and access remains limited throughout the world. However, there are no medical therapies recommended to promote the clearance of hr-HPV infection or CIN. Ultimately, even if less efficacious than excision procedures, medical therapies have the potential to decrease cervical cancer by eliminating barriers to treatment, such as access to treatment, or serving as an adjunct to surgical treatment in both high- and low-resource settings.

This review describes current research on topical therapies with the potential for self-application for the treatment of HPV or CIN. Therapies included are immune-modulators, anti-proliferative medications, antivirals, hormones, and herbal/alternative therapies. Randomized trials of immune-modulating (imiquimod), anti-proliferative (5-fluorouracil), and anti-viral (cidofovir) therapies have had the most promising results. However, no option has sufficient clinical trial evidence to be recommended as treatment for CIN 2–3 and surgery remains the standard of care.

The research described in this review serves as a guide for the development of future trials in the burgeoning arena of topical therapies for CIN 2–3.

Local Management of Anogenital Warts in Non-Immunocompromised Adults: A Network Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

No hierarchy of first-line treatments for anogenital warts (AGWs) is provided in international guidelines. This study aimed to determine the efficacy of topical treatments and ablative procedures for the management of AGWs.

METHODS

Twelve electronic databases were systematically searched from inception to August 2018. All randomized controlled trials (RCTs) comparing immunocompetent adults with AGWs who received at least 1 provider-administered or patient-administered treatment in at least 1 parallel group were included. Risk of bias assessment followed the Cochrane Handbook. The study endpoint was complete lesion response after clearance and recurrence assessment. A network meta-analysis was performed.

RESULTS

A network geometry was constructed based on 49 of the 70 RCTs included in our systematic review. All but 4 RCTs had a high risk of bias. The most efficacious treatments compared to placebo were surgery (RR 10.54; CI 95% 4.53-24.52), ablative therapy + imiquimod (RR 7.52; CI 95% 4.53-24.52), and electrosurgery (RR 7.10; CI 95% 3.47-14.53). SUCRA values confirmed the superiority of surgery (90.9%), ablative therapy + imiquimod (79.8%), and electrosurgery (77.1%). The most efficacious patient-administered treatments were podophyllotoxin 0.5% solution (63.5%) and podophyllotoxin 0.5% cream (62.2%).

CONCLUSIONS

With low-level evidence of most included RCTs, surgery and electrosurgery were superior to other treatments after clearance and recurrence assessment. Podophyllotoxin 0.5% was the most efficacious patient-administered treatment. Combined therapies should be evaluated in future RCTs in view of their identified effectiveness. The results of future RCTs should systematically include clinical type, number and location of AGWs, and sex of the patient, to refine therapeutic indications.

PROTOCOL REGISTRATION

PROSPERO-CRD42015025827.

Omiganan Enhances Imiquimod-Induced Inflammatory Responses in Skin of Healthy Volunteers

Omiganan (OMN; a synthetic cationic peptide) and imiquimod (IMQ; a TLR7 agonist) have synergistic effects on interferon responses in vitro. The objective of this study was to translate this to a human model for proof‐of‐concept, and to explore the potential of OMN add‐on treatment for viral skin diseases. Sixteen healthy volunteers received topical IMQ, OMN, or a combination of both for up to 4 days on tape‐stripped skin. Skin inflammation was quantified by laser speckle contrast imaging and 2D photography, and molecular and cellular responses were analyzed in biopsies. IMQ treatment induced an inflammatory response of the skin. Co‐treatment with OMN enhanced this inflammatory response to IMQ, with increases in perfusion (+17.1%; 95% confidence interval (CI) 5.6%–30%; P < 0.01) and erythema (+1.5; 95% CI 0.25%–2.83; P = 0.02). Interferon regulatory factor‐driven and NFκB‐driven responses following TLR7 stimulation were enhanced by OMN (increases in IL‐6, IL‐10, MXA, and IFNɣ), and more immune cell infiltration was observed (in particular CD4+, CD8+, and CD14+ cells). These findings are in line with the earlier mechanistic in vitro data, and support evaluation of imiquimod/OMN combination therapy in human papillomavirus‐induced skin diseases.

Local Management of Anogenital Warts in Non-immunocompromised Adults: A Systematic Review and Meta-analyses of Randomized Controlled Trials

INTRODUCTION

Several therapeutic options are available to manage anogenital warts (AGWs). However, no hierarchy of treatments is provided in the latest European and American recommendations. This study aimed to determine the efficacy and safety of local treatments for the management of AGWs.

METHODS

A search was conducted through 12 databases from inception to August 2018. All randomized controlled trials (RCTs) in which at least one parallel treatment group composed of immunocompetent adults with AGWs received at least one provider-administered or patient-administered treatment were included. Risk of bias assessment and meta-analyses of aggregated study data were performed on the basis of the Cochrane Handbook, and quality of evidence evaluation followed the Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach. Primary endpoints were complete clearance and recurrence at 3 months.

RESULTS

Seventy RCTs (9931 patients) were included. All but four RCTs had a high risk of bias. CO2 laser was slightly more efficacious than cryotherapy [risk ratio (RR) 2.05; 95% confidence interval (CI) 1.61-2.62], with fewer recurrences at 3 months (RR 0.28; 95% CI 0.09-0.89). Electrosurgery was slightly more efficacious than cryotherapy. No differences in efficacy or side effects were found between cryotherapy and imiquimod or trichloroacetic acid. Podophyllotoxin gel was slightly more efficacious than podophyllotoxin cream. 5-Fluorouracil (5-FU) was slightly more efficacious and caused less erosion than CO2 laser (RR 1.37; 95% CI 1.11-1.70).

CONCLUSION

The vast majority of included RCTs had a low level of evidence, thereby preventing the establishment of a hierarchy of treatments. Nevertheless, our results provide an overview of the main AGW treatments available for general practitioners and specialists. While provider-administered treatments are superior, patient-administered treatments (e.g., imiquimod, podophyllotoxin) are useful solutions for compliant patients.

PROTOCOL REGISTRATION

PROSPERO-CRD42015025827.

Human papillomavirus infection: protocol for a randomised controlled trial of imiquimod cream (5%) versus podophyllotoxin cream (0.15%), in combination with quadrivalent human papillomavirus or control vaccination in the treatment and prevention of recurrence of anogenital warts (HIPvac trial)

BACKGROUND

Anogenital warts are the second most common sexually transmitted infection diagnosed in sexual health services in England. About 90% of genital warts are caused by human papillomavirus (HPV) types 6 or 11, and half of episodes diagnosed are recurrences. The best and most cost-effective treatment for patients with anogenital warts is unknown. The commonly used treatments are self-administered topical agents, podophyllotoxin (0.15% cream) or imiquimod (5% cream), or cryotherapy with liquid nitrogen. Quadrivalent HPV (qHPV) vaccination is effective in preventing infection, and disease, but whether it has any therapeutic effect is not known.

METHODS AND DESIGN

To investigate the efficacy of clearance and prevention of recurrence of external anogenital warts by topical treatments, podophyllotoxin 0.15% cream or imiquimod 5% cream, in combination with a three-dose regimen of qHPV or control vaccination. 500 adult patients presenting with external anogenital warts with either a first or subsequent episode of anogenital warts will be entered into this randomised, controlled partially blinded 2 × 2 factorial trial.

DISCUSSION

The trial is expected to provide the first high-quality evidence of the comparative efficacy and cost-effectiveness of the two topical treatments in current use, as well as investigate the potential benefit of HPV vaccination, in the management of anogenital warts.

TRIAL REGISTRATION

The trial was registered prior to starting recruitment under the following reference numbers: International Standard Randomized Controlled Trial Number (ISRCTN) Registry - ISRCTN32729817 (registered 25 July 2014); European Union Clinical Trials Register (EudraCT) - 2013-002951-14 (registered 26 June 2013).

The Diagnostic and Therapeutic Challenge of Anal Intraepithelial Neoplasia

PURPOSE OF REVIEW

No single modality of care serves as the defined best practice for the treatment of anal intraepithelial neoplasia (AIN). This review aims to present the common treatment modalities germane to AIN while considering evolving evidence.

RECENT FINDINGS

AIN affords an opportunity to evaluate and treat patients before the development of invasive diseases. Efforts to screen for AIN have yielded mixed results. The major available pharmacotheraputic and surgical options offer efficacious options to reduce the bioburden of disease but can be met with high levels of recurrent disease. None affords a predictably durable response in severe disease. Vaccination as primary prevention will likely reduce the overall upward trend in AIN. Evidence suggests vaccination also affords improvement in recurrent disease. Early evidence reveals potential benefit in multimodal approaches to control AIN. Valuable data is anticipated from the phase III, randomized ANCHOR study evaluating the management of high-grade AIN in HIV +patients.

Industry sponsorship and research outcome

BACKGROUND

Clinical research affecting how doctors practice medicine is increasingly sponsored by companies that make drugs and medical devices. Previous systematic reviews have found that pharmaceutical-industry sponsored studies are more often favorable to the sponsor's product compared with studies with other sources of sponsorship. A similar association between sponsorship and outcomes have been found for device studies, but the body of evidence is not as strong as for sponsorship of drug studies. This review is an update of a previous Cochrane review and includes empirical studies on the association between sponsorship and research outcome.

OBJECTIVES

To investigate whether industry sponsored drug and device studies have more favorable outcomes and differ in risk of bias, compared with studies having other sources of sponsorship.

SEARCH METHODS

In this update we searched MEDLINE (2010 to February 2015), Embase (2010 to February 2015), the Cochrane Methodology Register (2015, Issue 2) and Web of Science (June 2015). In addition, we searched reference lists of included papers, previous systematic reviews and author files.

SELECTION CRITERIA

Cross-sectional studies, cohort studies, systematic reviews and meta-analyses that quantitatively compared primary research studies of drugs or medical devices sponsored by industry with studies with other sources of sponsorship. We had no language restrictions.

DATA COLLECTION AND ANALYSIS

Two assessors screened abstracts and identified and included relevant papers. Two assessors extracted data, and we contacted authors of included papers for additional unpublished data. Outcomes included favorable results, favorable conclusions, effect size, risk of bias and whether the conclusions agreed with the study results. Two assessors assessed risk of bias of included papers. We calculated pooled risk ratios (RR) for dichotomous data (with 95% confidence intervals (CIs)).

MAIN RESULTS

Twenty-seven new papers were included in this update and in total the review contains 75 included papers. Industry sponsored studies more often had favorable efficacy results, RR: 1.27 (95% CI: 1.17 to 1.37) (25 papers) (moderate quality evidence), similar harms results RR: 1.37 (95% CI: 0.64 to 2.93) (four papers) (very low quality evidence) and more often favorable conclusions RR: 1.34 (95% CI: 1.19 to 1.51) (29 papers) (low quality evidence) compared with non-industry sponsored studies. Nineteen papers reported on sponsorship and efficacy effect size, but could not be pooled due to differences in their reporting of data and the results were heterogeneous. We did not find a difference between drug and device studies in the association between sponsorship and conclusions (test for interaction, P = 0.98) (four papers). Comparing industry and non-industry sponsored studies, we did not find a difference in risk of bias from sequence generation, allocation concealment, follow-up and selective outcome reporting. However, industry sponsored studies more often had low risk of bias from blinding, RR: 1.25 (95% CI: 1.05 to 1.50) (13 papers), compared with non-industry sponsored studies. In industry sponsored studies, there was less agreement between the results and the conclusions than in non-industry sponsored studies, RR: 0.83 (95% CI: 0.70 to 0.98) (six papers).

AUTHORS' CONCLUSIONS

Sponsorship of drug and device studies by the manufacturing company leads to more favorable efficacy results and conclusions than sponsorship by other sources. Our analyses suggest the existence of an industry bias that cannot be explained by standard 'Risk of bias' assessments.

The Snowballing Literature on Imiquimod-Induced Skin Inflammation in Mice: A Critical Appraisal

Since 2009, the imiquimod- or Aldara-induced (3M Pharmaceuticals, St. Paul, MN) model of acute skin inflammation has become the most widely used mouse model in preclinical psoriasis studies. Although this model offers researchers numerous benefits, there are important limitations and possible confounding variables to consider. The imiquimod model requires careful consideration and warrants scrutiny of the data generated by its use. In this perspective, we provide an overview of the advantages and disadvantages of this mouse model and offer suggestions for its use in psoriasis research.

Evolving role of immunotherapy in the treatment of refractory warts

Cutaneous and genital warts are common dermatological conditions caused by the human papilloma virus (HPV). Although it is a benign condition, it causes disfigurement, has a tendency to koebnerize, and can be transmitted to others. This makes adequate and timely treatment important. There are several conventional treatments available with variable response. Topical and systemic immunotherapy has now found a significant place in the treatment of warts because of its nondestructive action, ease of use, and promising results. Through this review, we would like to present a brief overview of the various immunotherapeutic agents used. These include more established agents such as imiquimod, Mycobacterium w vaccine, bacillus Calmette-Guérin vaccine, measles, mumps, and rubella vaccine, Candida antigen, trichophyton antigen, tuberculin, zinc, cimetidine, levamisole, HPV vaccine, and autoimplantation therapy. Other agents such as contact immunotherapy which is sparsely used now than before and newer agents such as Corynebacterium parvum, sinecatechins, echinacea, propolis, glycyrrizinic acid, and Vitamin D have also been discussed. The mechanism of action of these agents, along with their dosage, mode of administration, duration of use, expected outcomes and comparative efficacy, evidence for their use, and expected side effects, if any, are reviewed.

An overview of early investigational drugs for the treatment of human papilloma virus infection and associated dysplasia

INTRODUCTION

High-risk HPV (HR-HPV) related invasive cervical cancer (ICC) causes >270,000 deaths per annum world-wide with over 85% of these occurring in low-resource countries. Ablative and excisional treatment modalities are restricted for use with high-grade pre-cancerous cervical disease with HPV infection and low-grade dysplasia mostly managed by a watch-and-wait policy.

AREAS COVERED

Various pharmacological approaches have been investigated as non-destructive alternatives for the treatment of HR-HPV infection and associated dysplasia. These are discussed dealing with efficacy, ease-of-use (physician or self-applied), systemic or locally applied, side-effects, cost and risks. The main focus is the perceived impact on current clinical practice of a self-applied, effective and safe pharmacological anti-HPV treatment.

EXPERT OPINION

Current prophylactic HPV vaccines are expensive, HPV type restricted and have little effect in already infected women. Therapeutic vaccines are under development but are also HPV type-restricted. At present, the developed nations use national cytology screening and surgical procedures to treat only women identified with HPV-related high-grade dysplastic disease. However, since HPV testing is rapidly replacing cytology as the test-of-choice, a suitable topically-applied and low-cost antiviral treatment could be an ideal solution for treatment of HPV infection per se with test-of-cure carried out by repeat HPV testing. Cytology would only then be necessary for women who remained HPV positive. Although of significant benefit in the developed countries, combining such a treatment with self-sampled HPV testing could revolutionise the management of this disease in the developing world which lack both the infrastructure and resources to establish national cytology screening programs.