Evaluation of imiquimod for the therapy of external genital and anal warts in comparison with destructive therapies

Assessment of sinecatechins 10% ointment used as proactive sequential therapy in recurrence rate of genital warts lesions after cryotherapy. The PACT-II Trial (postablation immunomodulator treatment of condylomata with sinecatechins): a prospective assessor-blinded, multicenter, pilot trial

BACKGROUND

Cryotherapy is commonly used as ablative treatment of external genital warts (EGW). However, after cryotherapy recurrence of lesions affects on average 45% (42-70%) of subjects in the 6 months after the treatment. Sinecatechins 10% are an effective topical treatment of EGW. A low recurrence rate (<6%) was observed in pivotal phase 3 trials conducted with this product. Topical sinecatechins have demonstrated to significantly reduce the recurrence rate of EGW in subjects treated with laser therapy (The PACT-I trial). So far, no prospective data are available regarding the efficacy of sinecathechins as immunomodulator sequential therapy after cryotherapy in EGW subjects. The purpose of this study was to assess the rate of recurrence lesions after the use of topical sinecatechins 10%, as sequential proactive immunomodulation treatment after cryotherapy in subjects with EGW (The PACT-II Trial: the postablation immunomodulator treatment of condylomata with sinecatechins trial) (Trial Registration number: ISRCTN44037479).

METHODS

In a prospective, assessor-blinded, multicenter trial a total of 55 subjects with a diagnosis of multiple EGW (36 men and 19 women, mean age 47±10 years) and a mean lesion number of 9±7, after their informed consent, were enrolled in the study. All subjects were treated with cryotherapy (an average of 2 sessions). After the ablative treatment, all subjects were instructed to apply sinecatechin 10% ointment 3 times daily for 4 consecutive months. The primary study endpoint was the evaluation (assessor-blinded) of recurrent lesions after 6 months (2 month of follow-up after the conclusion of topical treatment). The secondary study endpoints were the appearance of new EGW lesions (lesions affecting area not treated by cryotherapy) and the local tolerability.

RESULTS

At baseline, the mean number of EGW lesions were 9±7. After cryotherapy, the mean lesions number were reduced to 1.6±1.8. At month 4, EGW mean lesion number were 0.2±0.4 (P=0.0001 vs. after cryotherapy). At month 6, recurrence of lesions was detected in 10 subjects (18%; 95% CI: 9-30%) with an average of 1.4 lesions. Of these recurrent lesions, 6 occurred in completely healed lesions site after cryotherapy and 8 in partially healed ones. New lesions (outside the cryotherapy treated area) were observed in 10 subjects. The product was very well tolerated. No serious side effects were reported. Three subjects reported moderate skin irritation on the application site.

CONCLUSIONS

The PACT-II Trial has shown that the recurrence rate of EGW lesions after successful cryotherapy using sinecatechins as immunomodulator sequential therapy is lower in comparison with the percentage documented in the literature without sequential therapy (20 vs. 45%). These results are in line with already published data evaluating the role of sinecatechins after laser therapy (PACT-I trial). Future comparative, double-blind controlled trials assessing the efficacy of different proactive strategies are warranted.

Position statement for the diagnosis and management of anogenital warts

BACKGROUND

Anogenital warts (AGW) can cause economic burden on healthcare systems and are associated with emotional, psychological and physical issues.

OBJECTIVE

To provide guidance to physicians on the diagnosis and management of AGW.

METHODS

Fourteen global experts on AGW developed guidance on the diagnosis and management of AGW in an effort to unify international recommendations. Guidance was developed based on published international and national AGW guidelines and an evaluation of relevant literature published up to August 2016. Authors provided expert opinion based on their clinical experiences.

RESULTS

A checklist for a patient's initial consultation is provided to help physicians when diagnosing AGW to get the relevant information from the patient in order to manage and treat the AGW effectively. A number of frequently asked questions are also provided to aid physicians when communicating with patients about AGW. Treatment of AGW should be individualized and selected based on the number, size, morphology, location, and keratinization of warts, and whether they are new or recurrent. Different techniques can be used to treat AGW including ablation, immunotherapy and other topical therapies. Combinations of these techniques are thought to be more effective at reducing AGW recurrence than monotherapy. A simplified algorithm was created suggesting patients with 1-5 warts should be treated with ablation followed by immunotherapy. Patients with >5 warts should use immunotherapy for 2 months followed by ablation and a second 2-month course of immunotherapy. Guidance for daily practice situations and the subsequent action that can be taken, as well as an algorithm for treatment of large warts, were also created.

CONCLUSION

The guidance provided will help physicians with the diagnosis and management of AGW in order to improve the health and quality of life of patients with AGW.

A Pilot Study of the Immunologic, Virologic, and Pathologic Consequences of Intra-anal 5% Imiquimod in HIV-1-Infected Men With High-Grade Squamous Intraepithelial Lesions

BACKGROUND

Imiquimod can be used to treat internal anal high-grade squamous intraepithelial lesions. In HIV-1-infected individuals there is a theoretical concern for increased HIV replication in anorectal tissue secondary to imiquimod-induced mucosal inflammation.

OBJECTIVE

The purpose of this study was to assess local virologic, immunologic, and pathologic effects of imiquimod treatment in HIV-infected individuals.

DESIGN

This was a pilot study at a single academic center.

SETTINGS

The study was conducted at the University of Pittsburgh Anal Dysplasia Clinic.

PATIENTS

HIV-1-infected individuals with biopsy-confirmed internal anal high-grade squamous intraepithelial lesions were included.

INTERVENTION

Imiquimod cream was prescribed for intra-anal use 3 times per week for 9 weeks.

MAIN OUTCOME MEASURES

Anal human papillomavirus typing, anal and rectal tissue HIV-1 RNA and DNA quantification, cytokine gene expression, and anal histology were measured.

RESULTS

Nine evaluable participants (1 participant was lost to follow-up) were all white men with a median age of 46 years (interquartile range = 12 y) and a median CD4 T-cell count of 480 cells per cubic millimeter (interquartile range = 835). All were taking antiretroviral therapy, and 7 of 9 had HIV-1 RNA <50 copies per milliliter. The median dose of imiquimod used was 27.0 (interquartile range = 3.5), and there was a median of 11 days (interquartile range = 10 d) from last dose to assessment. There was no progression to cancer, no significant change in the number of human papillomavirus types detected, and no significant change in quantifiable cytokines/HIV-1 RNA or DNA levels in anal or rectal tissue. Seven (35%) of 20 high-grade lesions resolved to low-grade squamous intraepithelial lesions.

LIMITATIONS

The study was limited by the small number of participants and variable time to final assessment.

CONCLUSIONS

Intra-anal imiquimod showed no evidence of immune activation or increase in HIV-1 viral replication in anal and rectal tissue and confirmed efficacy for intra-anal high-grade squamous intraepithelial lesion treatment morbidity. See Video Abstract at http://links.lww.com/DCR/A498.

Therapeutic effect of imiquimod on dextran sulfate sodium-induced ulcerative colitis in mice

BACKGROUND

Imiquimod is a Toll-like receptor-7 agonist that regulates immunity and can be used as an immune adjuvant. Ulcerative colitis has a close correlation with immune disorder.

AIM

To investigate the therapeutic effect of imiquimod on dextran sulfate sodium (DSS)-induced colitis and explore the underlying mechanisms.

METHODS

C57BL/6J C57 mice received 3% DSS for 7 days to induce ulcerative colitis. Groups of mice were intraperitoneally injected with dexamethasone (DXM, 1.5 mg/kg) or imiquimod (IMQ, 30 mg/kg) at the same time daily. During the experimental period, clinical signs, body weight, stool consistency and visible fecal blood were monitored and recorded daily; colitis was evaluated by disease activity index (DAI) score and by histological score. At the conclusion of the experiment, the level of colonic myeloperoxidase (MPO) activity and the serum levels of the cytokines tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6) and interleukin 10 (IL-10) were measured.

RESULTS

Administration of 3% DSS for 7 days successfully induced acute colitis associated with diarrhea, bloody mucopurulent stool, body weight decreases, and other changes. Colitis severity was significantly ameliorated in the IMQ treatment groups, as determined by hematoxylin-eosin (HE) staining and histopathological scores. Moreover, IMQ significantly reduced the activity of MPO in colonic tissue and the serum levels of inflammatory cytokines, increased colon length and spleen weight, and effectively inhibited microscopic damage to the colon tissue.

CONCLUSION

IMQ had beneficial effects on DSS-induced ulcerative colitis, supporting its further development and clinical application in ulcerative colitis.

Immunotolerant indoleamine-2,3-dioxygenase is increased in condyloma acuminata

BACKGROUND

The tryptophan-depleting enzyme indoleamine-2,3-dioxygenase (IDO) is critical for the regulation of immunotolerance and plays an important role in immune-associated skin diseases.

OBJECTIVES

To analyse the level of IDO in condyloma acuminata (CA) and its role in this condition.

METHODS

IDO expression was assessed in the skin and peripheral blood of healthy controls and patients with CA. To assess the role of skin IDO in immunity, the ability of isolated epidermal cells to metabolize tryptophan and the influence on polyclonal T-cell mitogen (PHA)-stimulated T-cell proliferation were explored.

RESULTS

IDO median fluorescence intensities in peripheral blood mononuclear cells from patients with CA were similar to those from healthy controls. Immunohistochemistry showed that IDO⁺ cells were rare in normal skin and the control skin of patients with CA, but were greatly accumulated in wart tissue. Most fluorescence signals of IDO⁺ cells did not overlap with those of CD1a⁺ Langerhans cells. Human papillomavirus (HPV) DNA probe in situ hybridization showed a large number of IDO⁺ cells in the HPV^- site. Keratinocytes in the skin of healthy controls and the circumcised skin of patients with CA could minimally transform tryptophan into kynurenine, but IDO-competent epidermal cells from warts could transform tryptophan. In addition, these IDO-competent epidermal cells could inhibit PHA-stimulated T-cell proliferation. The addition of an IDO inhibitor, 1-methyl-d-tryptophan, restored the inhibited T-cell proliferation.

CONCLUSIONS

Abnormally localized high IDO expression might be involved in the formation of a local immunotolerant microenvironment.

HPV Carcinomas in Immunocompromised Patients

Human papillomavirus (HPV) infection is the most common sexually transmitted disease worldwide and can result in pre-malignancies or overt malignancies of the skin and mucosal surfaces. HPV-related illnesses are an important personal and public health problem causing physical, mental, sexual and financial detriments. Moreover, this set of malignancies severely affects the immunosuppressed population, particularly HIV-positive patients and organ-transplant recipients. There is growing incidence of HPV-associated anogenital malignancies as well as a decrease in the average age of affected patients, likely related to the rising number of high-risk individuals. Squamous cell carcinoma is the most common type of HPV-related malignancy. Current treatment options for HPV infection and subsequent disease manifestations include imiquimod, retinoids, intralesional bleomycin, and cidofovir; however, primary prevention with HPV vaccination remains the most effective strategy. This review will discuss anogenital lesions in immunocompromised patients, cutaneous warts at nongenital sites, the association of HPV with skin cancer in immunocompromised patients, warts and carcinomas in organ-transplant patients, HIV-positive patients with HPV infections, and the management of cutaneous disease in the immunocompromised patient.

Imiquimod for anogenital warts in non-immunocompromised adults

BACKGROUND

30% of people with anogenital warts (AGW) have spontaneous regression of lesions but there is no way to determine whether a specific lesion will remain. There are a wide range of options available for treating people with AGW and selection is based on clinician's experience, patient preferences and adverse effects. The imiquimod could offer the advantages of patient-applied therapies without incurring the limitations of provider-administered treatments.

OBJECTIVES

To assess the effectiveness and safety of imiquimod for the treatment of AGW in non-immunocompromised adults.

SEARCH METHODS

We searched the Cochrane Sexually Transmitted Infections Group Specialized Register (15 April 2014), CENTRAL (1991 to 15 April 2014), MEDLINE (1946 to 15 April 2014), EMBASE (1947 to 15 April 2014), LILACS (1982 to 15 April 2014), World Health Organization International Clinical Trials Registry (ICTRP) (15 April 2014), ClinicalTrials.gov (15 April 2014), Web of Science (2001 to 15 April 2014) and OpenGrey (15 April 2014). We also handsearched conference proceedings, contacted trial authors and reviewed the reference lists of retrieved studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing the use of imiquimod with placebo, any other patient-applied or any other provider-administered treatment (excluding interferon and 5-fluorouracil which are assessed in other Cochrane Reviews) for the treatment of AGW in non-immunocompromised adults.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion, extracted data and assessed risk of bias. We resolved any disagreements through consensus. The quality of the evidence was assessed using the GRADE approach.

MAIN RESULTS

Ten RCTs (1734 participants) met our inclusion criteria of which six were funded by industry. We judged the risk of bias of the included trials as high. Six trials (1294 participants) compared the use of imiquimod versus placebo. There was very low quality evidence that imiquimod was superior to placebo in achieving complete and partial regression (RR 4.03, 95% CI 2.03 to 7.99; RR 2.56, 95% CI 2.05 to 3.20, respectively). When compared with placebo, the effects of imiquimod on recurrence (RR 2.76, 95% CI 0.70 to 10.91), appearance of new warts (RR 0.76, 95% CI 0.58 to 1.00) and frequency of systemic adverse reactions (RR 0.91, 95% CI 0.63 to 1.32) were imprecise. We downgraded the quality of evidence to low or very low. There was low quality evidence that imiquimod led to more local adverse reactions (RR 1.73, 95% CI 1.18 to 2.53) and pain (RR 11.84, 95% CI 3.36 to 41.63).Two trials (105 participants) compared the use of imiquimod versus any other patient-applied treatment (podophyllotoxin and podophyllin). The estimated effects of imiquimod on complete regression (RR 1.09, 95% CI 0.80 to 1.48), partial regression (RR 0.77, 95% CI 0.40 to 1.47), recurrence (RR 0.49, 95% CI 0.21 to 1.11) or the presence of local adverse reactions (RR 1.24, 95% CI 1.00 to 1.54) were imprecise (very low quality evidence). There was low quality evidence that systemic adverse reactions were less frequent with imiquimod (RR 0.30, 95% CI 0.09 to 0.98).Finally, two trials (335 participants) compared imiquimod with any other provider-administered treatment (ablative methods and cryotherapy). There was very low quality of evidence that imiquimod did not have a lower frequency of complete regression (RR 0.84, 95% CI 0.56 to 1.28). There was very low quality evidence that imiquimod led to a lower rate of recurrence during six-month follow-up (RR 0.24, 95% CI 0.10 to 0.56) but this did not translate in to a lower recurrence from six to 12 months (RR 0.71, 95% CI 0.40 to 1.25; very low quality evidence). There was very low quality evidence that imiquimod was associated with less pain (RR 0.30, 95% CI 0.17 to 0.54) and fewer local reactions (RR 0.55, 95% CI 0.40 to 0.74).

AUTHORS' CONCLUSIONS

The benefits and harms of imiquimod compared with placebo should be regarded with caution due to the risk of bias, imprecision and inconsistency for many of the outcomes we assessed in this Cochrane Review. The evidence for many of the outcomes that show imiquimod and patient-applied treatment (podophyllotoxin or podophyllin) confer similar benefits but fewer systematic reactions with the Imiquimod, is of low or very low quality. The quality of evidence for the outcomes assessing imiquimod and other provider-administered treatment were of very low quality.

A prospective, open, comparative study of 5% potassium hydroxide solution versus cryotherapy in the treatment of genital warts in men

BACKGROUND

Genital warts are caused by human papillomavirus infection and represent one of the most common sexually transmitted diseases. Many infections are transient but the virus may recur, persist, or become latent. To date, there is no effective antiviral treatment to eliminate HPV infection and most therapies are aimed at the destruction of visible lesions. Potassium hydroxide is a strong alkali that has been shown to be safe and effective for the treatment of genital warts and molluscum contagiosum. Cryotherapy is considered one of the most established treatments for genital warts. No comparative trials have been reported to date on the use of potassium hydroxide for genital warts.

OBJECTIVE

A prospective, open-label, randomized clinical trial was conducted to compare topical potassium hydroxide versus cryotherapy in the treatment of genital warts affecting immunocompetent, sexually active men.

METHODS

Over a period of 10 months, 48 patients were enrolled. They were randomly divided into two groups and selected on an alternative basis for either potassium hydroxide therapy or cryotherapy. While response to therapy did not differ substantially between both treatment modalities, side effects such as local pain and post-treatment hypopigmentation were considerably more prevalent in the groups treated using cryotherapy.

RESULT

In our study, potassium hydroxide therapy proved to be at least as effective as cryotherapy and offered the benefit of a better safety profile.

CONCLUSION

Topical 5% potassium hydroxide presents an effective, safe, and low-cost treatment modality for genital warts in men and should be included in the spectrum of therapies for genital warts.

The toll-like receptor agonist imiquimod is active against prions

Using a yeast-based assay, a previously unsuspected antiprion activity was found for imiquimod (IQ), a potent Toll-like receptor 7 (TLR7) agonist already used for clinical applications. The antiprion activity of IQ was first detected against yeast prions [PSI⁺] and [URE3], and then against mammalian prion both ex vivo in a cell-based assay and in vivo in a transgenic mouse model for prion diseases. In order to facilitate structure-activity relationship studies, we conducted a new synthetic pathway which provides a more efficient means of producing new IQ chemical derivatives, the activity of which was tested against both yeast and mammalian prions. The comparable antiprion activity of IQ and its chemical derivatives in the above life forms further emphasizes the conservation of prion controlling mechanisms throughout evolution. Interestingly, this study also demonstrated that the antiprion activity of IQ and IQ-derived compounds is independent from their ability to stimulate TLRs. Furthermore, we found that IQ and its active chemical derivatives inhibit the protein folding activity of the ribosome (PFAR) in vitro.

Human papillomavirus-related genital disease in the immunocompromised host: Part II

Human papillomavirus is responsible for common condyloma acuminata and a number of premalignant and malignant anogenital lesions. The immunocompromised population is at particular risk because of a higher incidence of malignant transformation. Lesions in this population may prove refractory to standard treatment. This is part II of a two-part review that will discuss the treatment of condyloma acuminata and vaginal, vulvar, penile, and anal intraepithelial neoplasias. This article will provide an updated review of available treatments, with a focus on recent advances and the challenges faced in successfully treating human papillomavirus lesions in the immunocompromised host.

Laser-assisted topical drug delivery by using a low-fluence fractional laser: imiquimod and macromolecules

The aim of this study was to evaluate the ability of a low-fluence fractional erbium:yttrim-aluminum-garnet (Er:YAG) laser, with a wavelength of 2940 nm, for enhancing and controlling the skin permeation of imiquimod and macromolecules such as polypeptides and fluorescein isothiocyanate (FITC)-labeled dextran (FD). The in vitro permeation has been determined using a Franz diffusion cell, with porcine skin and nude mouse skin as the barriers. Hyperproliferative and ultraviolet (UV)-irradiated skins were also used as barrier models to mimic the clinical therapeutic conditions. Confocal laser scanning microscopy (CLSM) was used to examine the in vivo nude mouse skin uptake of peptide, FITC, and FD. Both in vitro and in vivo results indicated an improvement in permeant skin delivery by the laser. The laser fluence and number of passes were found to play important roles in controlling drug transport. Increases of 46- and 127-fold in imiquimod flux were detected using the respective fluences of 2 and 3 J/cm(2) with 4 pulses. An imiquimod concentration of 0.4% from aqueous vehicle with laser treatment was sufficient to approximate the flux from the commercial cream with an imiquimod dose of 5% without laser treatment, indicating a reduction of the drug dose by 125-fold. The enhancement of peptide permeation was size and sequence dependent, with the smaller molecular weight (MW) and more-hydrophilic entities showing greater enhancing effect. Skin permeation of FD with an MW of at least 150 kDa could be achieved with fractional laser irradiation. CLSM images revealed intense green fluorescence from the permeants after exposure of the skin to the laser. The follicular pathway was significant in laser-assisted permeation.

Topical treatment of anogenital human papillomavirus infection in male patients

Background: Human papillomavirus (HPV)-associated anogenital warts have a prevalence of up to 78% in sexually active men. Some HPV subtypes bear a considerable oncogenic potential. Materials & methods: Original papers on the treatment of external anogenital warts were included in a meta-analysis to assess the most effective topical treatment. Results: Clearance rates were 0–6.5% for placebo treatment, 76.6% for podophyllotoxin 0.15% cream administered for 4 weeks, 61.5% for podophyllotoxin 0.5% solution (2–6 weeks) and 53.7% for imiquimod 5% cream (12–16 weeks). For male patients, the intent-to-treat analysis demonstrated statistically significant superiority of podophyllotoxin preparations versus imiquimod (p < 0.0001 and p < 0.005, respectively). Clearance rates of locally ablative treatments, such as surgery, cryotherapy, electrocautery and carbon dioxide laser, differed widely without clear superiority of a specific ablative technique. In HIV-positive patients, all treatment options yielded lower clearance rates and higher recurrence rates. Conclusion: While preventive vaccines might reduce HPV-associated morbidity for future generations, those with active HPV disease still need to be treated with customary treatment options. In male patients, podophyllotoxin preparations yielded higher response rates than imiquimod.