Cantharidin is Superior to Trichloroacetic Acid for the Treatment of Non-mucosal Genital Warts: A Pilot Randomized Controlled Trial

Cantharidin analogue alleviates dextran sulfate sodium-induced colitis in mice by inhibiting the activation of NF-κB signaling

Ulcerative colitis is a chronic inflammatory disease with a remitting-relapsing clinical course, it has evolved into a global burden given its high incidence worldwide. Cantharidin (CTD) derivatives are a class of compounds whose structures characterized with a 7-oxabicyclo [2.2.1]heptane core. Though potent cytotoxicity CTD and its derivatives showed, their clinical usage as anti-cancer drugs was limited by the toxicity in organs. In order to find new CTD analogues with good activity and lower toxicity, 21 CTD analogues with or without alkynyl substitution at C5 position of 7-oxabicyclo [2.2.1]heptane core were synthesized, some compounds showed better in vitro anti-inflammatory activity compared to CTD and norcantharidin (NCTD). Based on the structure-activity relationship results of in vitro experiment, analogue 3i was chosen for further study. Results from the acute toxicity in mice showed that 3i was hypotoxic with the single-dose MTD (maximum tolerated dose) for oral administration is over 1852 mg/kg, at least 35-fold lower than that of NCTD. Mechanism study indicated that 3i could potently inhibit TNF-α induced activation of NF-κB signaling by down-regulation the expression levels of phosphor- IKK, IκBα, and NF-κB p65, and alleviated dextran sulfate sodium-induced colitis in mice. This study indicated that CTD analogues with alkynyl substitution at C5 position of 7-oxabicyclo [2.2.1]heptane core is a kind of new compounds with good anti-inflammatory activity and lower toxicity in vivo, and might be used as therapeutic agents for inflammatory diseases.

The Effectiveness of Chemical Cautery and Electrosurgery on Anogenital Wart: Systematic Review

Introduction

Anogenital warts (AGW) is one of the sexually transmitted infections (STIs) caused by human papillomavirus (HPV). Treatment modalities of AGW yield low clearance and recurrence rate, so that chemical cautery with trichloroacetic acid (TCA) and electrosurgery are widely used to remove the lesions without any severe side effects.

Objective

To investigate the efficacy of chemical cautery with TCA and electrosurgery in AGW based on clinical trials or case series.

Methods

The systematic review was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) but not registered to the International Prospective Register of Systematic Review (PROSPERO). To acquire proper and accurate information from relevant literature, two databases PubMed and the Cochrane Library were searched from January 2013 to March 2023.

Results

Thirteen studies were included in this systematic review, comprising seven articles on chemical cautery and six electrosurgery articles. The highest cure rate of chemical cautery with TCA was 94.1% while electrosurgery was 100%. A relatively low recurrence rate during 1 year follow-up was observed in electrosurgery with 14.6%, whereas the chemical cautery was 27.6%.

Conclusion

Electrosurgery for AGW treatment had higher cure rate with lower recurrence rate compared to chemical cautery with TCA. Numerous adverse effects of electrosurgery were reported include bleeding and scar formation as high risk of HPV infection.

A Retrospective Study of Clinical Efficacy of Cantharidin Cream for Verruca Plantaris

Verruca plantaris (plantar wart) is a type of benign feet hyperplasia that is caused by a human papillomavirus (HPV) infection. In this study, we aimed to assess the clinical efficacy underlying cantharidin cream in the treatment of Verruca plantaris compared to CO₂ laser and liquid nitrogen cryotherapy. One hundred and fifty patients affected with Verruca plantaris were enrolled in this retrospective clinical study. The treatment efficacy rate in the three groups was assessed 4 and 12 weeks after treatment. After 4 weeks of treatment, 46 cases in the externally applied cantharidin cream therapy group were cured with an apparent efficiency of 92.0% (46/50). Contrarily, 42 cases in the CO₂ laser group were cured with 84.0% (42/50) efficiency, while 40 cases in the liquid nitrogen cryotherapy group were cured with an apparent efficiency of 80.0% (40/50). Although the clinical cure rate of Verruca plantaris in the Cantharidin group was greater than in the CO₂ laser group and in the liquid nitrogen cryotherapy group, there were no statistical differences found among the three groups (P = 0.225). After 12 weeks of treatment, 43 cases in the external cantharidin cream therapy group were cured with an apparent efficiency of 86.0% (43/50). Similarly, 39 cases in the CO₂ laser group were cured with an apparent efficiency of 78.0% (39/50), while 36 cases in the liquid nitrogen cryotherapy group were cured with an apparent efficiency of 72.0% (36/50). The statistical differences among the three groups were not found (P =0.230), but the resolution rate of warts in Cantharidin group was the highest among the three groups. The results from this study demonstrated that external cantharidin cream therapy could be served as an alternative treatment for Verruca plantaris.

Formaldehyde 5% in Flexible Collodion Compared to Cryotherapy for Treatment of Female Genital Warts: A Randomized Clinical Trial

Objectives

Genital wart is a sexually transmitted disease caused by human papillomavirus (HPV) and is responsible for discomfort, and decreased quality of life and productivity in victims with a high recurrence rate after treatments. This study aimed to compare the efficacy and safety of formaldehyde 5% with cryotherapy for the treatment of female genital warts.

Methods

Eighty women with at least two similar genital warts who visited the outpatient dermatology clinic of Shahid Faghihi hospital, Shiraz, Iran, were enrolled in this study. One lesion of each patient was self-treated with formaldehyde 5% in flexible collodion gel once daily for 28 days and the other matched lesion was treated by weekly repeated cryotherapy courses. The number of eradicated lesions and the mean days needed to treat, pain scores, complications and patient satisfaction were compared between the treatment methods.

Results

Complete clearance of lesions was observed in 58.7% of formaldehyde-treated lesions compared to 88.7% for cryotherapy (P value = 0.000). With formaldehyde-treated lesions, 51% complained of pain, 36.3% had pruritus, 86.3% had skin dryness, 88.8% complained of burning sensation and 93.7% showed erythema. In the cryotherapy group, 92.5% complained of pain, 15% had burning sensation, 75% showed erythema, 5% had atrophy, 80% developed post-inflammatory hyper or hypopigmentation (PIH) and 92.5% suffered from ulceration. Seventy-five (93%) found it easy to apply and (47) 58% were satisfied with their treatment results.

Conclusions

Self-administration of formaldehyde 5% resulted in a lower clearance rate but had better cosmetic outcomes with lower pain scores compared to cryotherapy.

Phase II, Double-Blind, Vehicle-Controlled Study to Determine the Cantharidin Dose Regimen, Efficacy, Safety, and Tolerability of VP-102 in Subjects with External Genital Warts

BACKGROUND

External genital warts are caused by various subtypes of the human papilloma virus and spread through direct skin-to-skin contact. Approximately 1% of the US population have external genital warts. Although cantharidin has been used to treat external genital warts for decades, there are no US Food and Drug Administration-approved cantharidin products and no reliable or controlled sources of cantharidin available. VP-102 is a drug-device combination product containing cantharidin (0.7% w/v) in a single-use shelf-stable applicator.

OBJECTIVE

The objective of this randomized, double-blind, vehicle-controlled, phase II clinical trial was to determine the optimal regimen for the treatment, safety, and efficacy of VP-102 in external genital warts.

METHODS

The study was conducted in two parts. Part A was dose finding and Part B was performed following the completion of Part A for a safety and efficacy evaluation. Following completion of Part A, 6-h and 24-h VP-102 regimens under occlusion were selected to be evaluated in Part B.

RESULTS

Pooled results from Part B and Part A of the 6-h and 24-h VP-102 treatment regimens showed that 36.7% and 33.3% of participants achieved complete clearance of all treatable external genital warts at the end of treatment vs 4.2% (p < 0.0048) and 0% (p < 0.0075) with the vehicle. Adverse events experienced by the VP-102-treated participants were consistent with the pharmacodynamic action of cantharidin as a vesicant and were primarily mild to moderate in severity. The most common adverse events included application-site vesicles, pain, and erythema. No participants discontinued the study because of adverse events and no serious adverse events were deemed treatment related.

CONCLUSIONS

The adverse event profile and efficacy of VP-102 under occlusion demonstrated in this study support the conclusion that a 6-h or up to 24-h exposure regimen represents an acceptable risk:benefit profile and justifies the conduct of a larger vehicle-controlled phase III study in external genital warts.

CLINICAL TRIAL REGISTRATION

NCT03981822, actual study start date: 25 June, 2019; actual primary completion date: 21 May, 2020; actual study completion date: 8 July, 2020.

Anticancer Attributes of Cantharidin: Involved Molecular Mechanisms and Pathways

Cancer is a preeminent threat to the human race, causing millions of deaths each year on the Earth. Traditionally, natural compounds are deemed promising agents for cancer treatment. Cantharidin (CTD)-a terpenoid isolated from blister beetles-has been used extensively in traditional Chinese medicines for healing various maladies and cancer. CTD has been proven to be protein phosphatase 2A (PP2A) and heat shock transcription factor 1 (HSF-1) inhibitor, which can be potential targets for its anticancer activity. Albeit, it harbors some toxicities, its immense anticancer potential cannot be overlooked, as the cancer-specific delivery of CTD could help to rescue its lethal effects. Furthermore, several derivatives have been designed to weaken its toxicity. In light of extensive research, the antitumor activity of CTD is evident in both in vitro as well as in vivo cancer models. CTD has also proven efficacious in combination with chemotherapy and radiotherapy and it can also target some drug-resistant cancer cells. This mini-review endeavors to interpret and summarize recent information about CTD anticancer potential and underlying molecular mechanisms. The pertinent anticancer strength of CTD could be employed to develop an effective anticarcinogenic drug.

Penile warts: an update on their evaluation and management

Background

Penile warts are the most common sexually transmitted disease in males. Clinicians should be familiar with the proper evaluation and management of this common condition.

Objective

To provide an update on the current understanding, evaluation, and management of penile warts.

Methods

A PubMed search was completed in Clinical Queries using the key terms 'penile warts' and 'genital warts'. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews.

Results

Penile warts are caused by human papillomavirus (HPV), notably HPV-6 and HPV-11. Penile warts typically present as asymptomatic papules or plaques. Lesions may be filiform, exophytic, papillomatous, verrucous, hyperkeratotic, cerebriform, fungating, or cauliflower-like. Approximately one-third of penile warts regress without treatment and the average duration prior to resolution is approximately 9 months. Active treatment is preferable to watchful observation to speed up clearance of the lesions and to assuage fears of transmission and autoinoculation. Patient-administered therapies include podofilox (0.5%) solution or gel, imiquimod 3.75 or 5% cream, and sinecatechins (polypheron E) 15% ointment. Clinician-administered therapies include podophyllin, cryotherapy, bichloroacetic or trichloroacetic acid, oral cimetidine, surgical excision, electrocautery, and carbon dioxide laser therapy. Patients who do not respond to first-line treatments may respond to other therapies or a combination of treatment modalities. Second-line therapies include topical/intralesional/intravenous cidofovir, topical 5-fluorouracil, and topical ingenol mebutate.

Conclusion

No single treatment has been shown to be consistently superior to other treatment modalities. The choice of the treatment method should depend on the physician's comfort level with the various treatment options, the patient's preference and tolerability of treatment, and the number and severity of lesions. The comparative efficacy, ease of administration, adverse effects, cost, and availability of the treatment modality should also be taken into consideration.

Advances in Designing and Developing Vaccines, Drugs and Therapeutic Approaches to Counter Human Papilloma Virus

Human papillomavirus (HPV) is a viral infection with skin-to-skin based transmission mode. HPV annually caused over 500,000 cancer cases including cervical, anogenital and oropharyngeal cancer among others. HPV vaccination has become a public-health concern, worldwide, to prevent the cases of HPV infections including precancerous lesions, cervical cancers, and genital warts especially in adolescent female and male population by launching national programs with international alliances. Currently, available prophylactic and therapeutic vaccines are expensive to be used in developing countries for vaccination programs. The recent progress in immunotherapy, biotechnology, recombinant DNA technology and molecular biology along with alternative and complementary medicinal systems have paved novel ways and valuable opportunities to design and develop effective prophylactic and therapeutic vaccines, drugs and treatment approach to counter HPV effectively. Exploration and more researches on such advances could result in the gradual reduction in the incidences of HPV cases across the world. The present review presents a current global scenario and futuristic prospects of the advanced prophylactic and therapeutic approaches against HPV along with recent patents coverage of the progress and advances in drugs, vaccines and therapeutic regimens to effectively combat HPV infections and its cancerous conditions.