[Skin reactions related to molluscum contagiosum infection]. / Reacciones cutáneas relacionadas a la infección por molusco contagioso.

Molluscum contagiosum (MC) is a common viral infection in children, immunocompromised, and sexually active adults. Its usual clinical presentation is 2-5 mm, whitish or skin-colored papules, with a shiny surface and central umbilication, generally clustered and randomly distributed over the skin surface. Dermoscopy reveals yellowish-white polylobulated structures with peripheral telangiectasia. Diagnosis is usually clinical supported by dermoscopy. However, in some cases, inflammatory manifestations can be associated with this infection and can mimic other dermatological conditions, making the diagnosis difficult and leading to unnecessary treatments. The objective of this article is to describe the main skin reactions associated with MC infection in order to provide a diagnostic and initial management tool for clinicians dealing with these conditions. Reported manifestations include the BOTE sign, perilesional eczema, Gianotti-Crosti syndrome-like reaction, ID reaction, erythema annulare centrifugum, erythema multiforme, folliculitis, white halo, and atypical manifestations (giant, disseminated, necrotic, polypoidal, and nodular lesions, pseudocysts, abscesses). In pediatric patients with the clinical manifestations described above, infection by molluscum contagiosum pox virus should be considered among the differential diagnoses, and referral to a dermatologist should be made in selected cases.

Molluscum Contagiosum Virus: Biology and Immune Response.

Molluscum contagiosum virus is a poxvirus belonging to the Poxviridae family, which includes Orthopoxvirus, Parapoxvirus, Yantapoxvirus, Molluscipoxvirus, Smallpox virus, Cowpox virus and Monkeypox virus. MCV belongs to the genus Molluscipoxvirus and has a tropism for skin tissue. MCV infects keratinocytes and, after an incubation period of 2 weeks to 6 weeks, causes a breakdown of the skin barrier with the development of papules of variable size depending on the proper functioning of the immune response (both adaptive and acquired). MCV only infects humans and does not cause viraemia. MCV encodes for several inhibitory proteins responsible to circumvent the immune response through different signalling pathways. Individuals who can be infected with MCV are children, immunocompromised individuals such as organ transplant recipients and Human Immunodeficiency Virus (HIV)-infected individuals. Current treatments to manage MCV-induced lesions are different and include the use of immunomodulators, which, however, do not provide an effective response.

Potency of a small molecule that targets the molluscum contagiosum virus processivity factor increases when conjugated to a tripeptide.

We recently developed compound FC-7269 for targeting the Molluscum contagiosum virus processivity factor (mD4) and demonstrated its ability to inhibit viral processive DNA synthesis in vitro and cellular infection of an mD4-dependent virus (Antiviral Res 211, 2023,105520). However, despite a thorough medicinal chemistry campaign we were unable to generate a potent second analog as a requisite for drug development. We overcame this impasse, by conjugating a short hydrophobic trivaline peptide to FC-7269 to produce FC-TriVal-7269 which significantly increased antiviral potency and reduced cellular toxicity.

Does Molluscum Contagiosum Need to be Managed Differently in Atopic Children?

The association between molluscum contagiosum and concomitant atopic dermatitis and its impact on clinical features and treatment outcomes remains unclear. This retrospective study, conducted in the paediatric dermatology clinic of a tertiary medical centre, aimed to compare molluscum patients with and without atopic dermatitis. A total of 615 children with molluscum were included, 13.17% of whom had atopic dermatitis. While the latter group exhibited higher lesion count and itchiness (p=0.026 and p=0.044, respectively), no significant differences were observed in average lesion diameter, ulceration, purulence, and erythema (p=0.239, p=0.730, p=0.682, and p=0.296, respectively). Both groups showed comparable responses to molluscum-specific and supportive treatments, with no distinct difference in outcomes or recurrence of visits. It was concluded that atopic dermatitis does not exacerbate molluscum morbidity, inflammation markers, treatment outcomes or recurrence rates.

Association between filaggrin gene mutations and the clinical features of molluscum contagiosum: The Yamanashi Adjunct Study of the Japan Environment and Children's Study.

Previous studies have reported swimming, atopic dermatitis, and filaggrin (FLG) gene mutations as risk factors for molluscum contagiosum (MC) infection. FLG gene mutations impair skin barrier function. The aim of this study was to determine the impact of FLG mutations on the incidence and clinical features of MC. We used data from 2036 children who participated in the Yamanashi Adjunct Study of the Japan Environment and Children's Study, a prospective, birth cohort study. A questionnaire for caregivers (when children were 4 and 8 years of age) asked about clinical features including previous MC incidence and treatment, number of MC lesions at first visit, and time to resolution. Participants underwent genotyping to detect six FLG mutations that are common in the Japanese population. A logistic regression model was used to analyze the association between MC incidence and FLG mutations, adjusted for potential confounders. The cumulative incidence of MC at age 8 years was 47.1%. Among participants with a history of MC, 67.6% had undergone curettage. FLG mutation was a significant risk factor for MC incidence (adjusted odds ratio [aOR] 1.69, 95% confidence interval [CI] 1.18-2.42). Swimming and atopic dermatitis were also significant risk factors for MC. There was no significant association between FLG mutation and the number of MC lesions at the first visit or the time to resolution of lesions. FLG mutation is a risk factor for MC incidence; however, FLG mutations do not affect the number of MC lesions at presentation or the time to resolution.

Berdazimer Topical Gel, 10.3%: First Approval.

Berdazimer topical gel, 10.3% (ZELSUVMI™) is a nitric oxide (NO) releasing topical gel developed by Novan Inc. (a Ligand Pharmaceuticals company) for the treatment of molluscum contagiosum (MC). Novan has used their proprietary NO-based technology platform (NITRICIL™), which stores gaseous NO species on large polymers, in the development of berdazimer topical gel, 10.3%. In January 2024, berdazimer topical gel, 10.3% was approved for the topical treatment of MC in adult and paediatric patients 1 year of age and older in the USA. This article summarizes the milestones in the development of berdazimer topical gel, 10.3% leading to this first approval for the treatment of MC.

Berdazimer gel for molluscum contagiosum in patients with atopic dermatitis.

OBJECTIVE: Controlling molluscum contagiosum (MC) infections is critical in atopic dermatitis (AD) management. This post hoc analysis assessed the efficacy and safety of berdazimer gel, 10.3% (topical, antiviral, nitric oxide-releasing medication) versus vehicle in MC patients with or without AD. METHODS: Three Phase 3, multicenter, randomized, double-blind, vehicle-controlled, parallel-group trials (B-SIMPLE[berdazimer sodium in molluscum patients with lesions]1, -2, -4) enrolled patients 6 months and older with 3-70 mollusca. Berdazimer or vehicle was applied once daily to all MC lesions for 12 weeks. Data from three Phase 3 studies were integrated for subgroup efficacy and safety assessments using several weighted meta-analysis approaches. Patients with concurrent AD or a history of AD/eczema were categorized as AD+ subgroup (AD- when absent). Primary efficacy endpoint: complete lesion clearance at Week 12. Safety endpoints included adverse events (AEs) through Week 24 and local skin reactions through Week 12. RESULTS: Of 1598 enrolled patients, 209 (13.1%) were AD+. Baseline mean lesion counts were greater in AD+ (26.4) than AD- (19.3). Complete clearance rates were higher at Week 12 for berdazimer compared with vehicle in AD+ (n = 209; 35.0% vs. 27.4%; odds ratio [OR], 1.3; 95% CI, 0.7-2.5) and AD- (n = 1389; 29.1% vs. 18.9%; OR 1.8; 95% CI 1.4-2.4) subgroups. AEs in AD+ were application-site pain (21.6% with berdazimer vs. 11.9% with vehicle), dermatitis (12.8% vs. 2.4%), and erythema (9.6% vs. 7.1%). CONCLUSIONS: Berdazimer gel showed favorable efficacy regardless of AD status. Berdazimer-induced erythema may be indistinguishable from AD symptoms or with inflammatory response upon resolution of molluscum.

Intralesional injection of tuberculin purified protein derivative (PPD) versus measles, mumps, and rubella (MMR) vaccine in treatment of molluscum contagiosum: a comparative study.

Molluscum contagiosum (MC) is a skin and mucous membrane infection caused by the molluscum virus (MCV). To evaluate safety and efficacy of intralesional injection of tuberculin purified protein derivative (PPD) antigen injection versus MMR (mumps, measles, rubella) antigen for the treatment of molluscum contagiosum (MC). A total of thirty clinically confirmed patients of molluscum were recruited for this trial. Patients who were divided into three groups (A, B and C). Each group consisted of (30) patients. Group (A) subjects received intralesional MMR injections, group (B) subjects received intralesional PPD injection and group (C) received intralesional saline injection. The results of the present study revealed complete clearance of the injected lesions in 12 patients (80%), partial response in 3 patients (20%) of group (A). In group (B), complete clearance of the treated warts was observed in 11 patients (73.3%) and partial response in 4 (26.7%) of patients. In group (C), the majority of patients 8 (53.3%) demonstrated no response while 7 (46.7%) patients showed only partial clearance. We established a good safety and efficacy profile for tuberculin PPD and MMR antigens in treatment of molluscum contagiosum.

Poxvirus infections in dermatology - the neglected, the notable, and the notorious.

The family Poxviridae currently comprises 22 genera that infect vertebrates. Of these, members of the Ortho-, Para-, Mollusci- and Yatapoxvirus genera have been associated with human diseases of high clinical relevance in dermatology. Historically, smallpox had been a notorious health threat until it was declared eradicated by the World Health Organization in 1979. Today, dermatologists are confronted with a variety of poxviral infections, such as farmyard pox, which occurs as a zoonotic infection after contact with animals. In the tropics, tanapox or vaccinia may be in the differential diagnosis as neglected tropical dermatoses. Molluscum contagiosum virus infection accounts for significant disease burden worldwide and is classified as a sexually transmitted infection in certain scenarios. Recently, mpox (monkeypox) has emerged as a public health emergency of international concern, requiring rapid recognition and appropriate management by dermatologists and infectious disease specialists. Advances and new insights into the epidemiology, diagnosis, clinical manifestations and complications, treatment, and prevention of poxviral infections require a high level of expertise and interdisciplinary skills from healthcare professionals linking virology, infectious diseases, and dermatology. This CME article provides a systematic overview and update to assist the practicing dermatologist in the identification, differential diagnosis, and management of poxviral infections.

Berdazimer gel for molluscum contagiosum: An integrated analysis of 3 randomized controlled trials.

BACKGROUND: An out-of-office therapeutic agent indicated for molluscum contagiosum is needed. OBJECTIVE: To assess the efficacy and safety of berdazimer gel, 10.3% (a topical, antiviral, nitric oxide-releasing medication) versus vehicle. METHODS: Berdazimer gel, 10.3% or vehicle was applied once daily to all molluscum contagiosum lesions for 12 weeks in patients ≥6 months with 3-70 mollusca. Efficacy assessment: complete lesion clearance and partial clearance at week 12. Safety and tolerability assessment: adverse events through week 24 and local skin reactions through week 12. RESULTS: There were 1598 patients enrolled (n = 917 berdazimer, n = 681 vehicle). Berdazimer was superior to vehicle at week 12 in complete clearance rates, 30.0% versus 19.8% (odds ratio, 1.75; 95% CI, 1.38-2.23, P < .001). Subgroup analyses of primary efficacy showed consistent favorable efficacy for berdazimer across most subgroups, including age, sex, baseline lesion count, and disease duration. Berdazimer provided favorable outcome for partial clearance. Application-site pain (18.7% vs 4.8% in berdazimer vs vehicle) and erythema (11.7% vs 1.3%), mostly mild to moderate, were the most common local skin reactions. LIMITATIONS: Berdazimer sodium in molluscum patients with lesions (B-SIMPLE) trials enrolled only US patients; no efficacy assessments beyond week 12. CONCLUSIONS: Berdazimer gel, 10.3% showed favorable efficacy and safety across subgroups.

Cantharidin Topical Solution 0.7%: First Approval.

Cantharidin (YCANTH™) is a proprietary drug-device combination product containing a formulation of cantharidin 0.7% topical solution (a vesicant naturally derived from blister beetles) delivered via a single-use applicator that has been developed by Verrica Pharmaceuticals Inc. for the treatment of molluscum contagiosum and is also being developed for the treatment of warts. In July 2023, YCANTH™ (cantharidin 0.7% topical solution) was approved for the topical treatment of molluscum contagiosum in adult and pediatric patients 2 years of age and older in the USA. This article summarizes the milestones in the development of cantharidin 0.7% topical solution leading to this first approval for the topical treatment of molluscum contagiosum in adult and pediatric patients 2 years of age and older.

Molluscum contagiosum survey - common approach and attitude towards treatment and research in Dutch general practice.

BACKGROUND: Molluscum contagiosum (MC) can cause significant burden in children. So far, pharmacological treatment has not been proven beneficial. More rigorous interventions have not been well studied. Current guidelines advise a "wait and see" policy. However, children and their parents frequently visit their GP requesting intervention. Therefore, the aim of this study was to gain insight into the approach to MC by GPs and parents' expectations and to investigate willingness to participate in an interventional study. METHODS: A survey study was carried out among GPs and parents using a questionnaire for each group inquiring about MC and potential study participation. Descriptive statistics were used to analyze results and logistical regression to investigate factors influencing participation. RESULTS: The majority of GPs (88%) preferred an expectative approach; only 21% were willing to participate in a trial as proposed. GPs estimating ≥ 50% of parents would request treatment, were more likely to participate. Most responding parents did or would visit their GP requesting treatment. In contrast to GPs, 58% were willing to participate. Parents preferring cryotherapy or curettage were more likely to participate. CONCLUSION: Our study demonstrated that the majority of GPs preferred a conservative approach, adhering to current guidelines. However, most parents preferred treatment to resolve MC and symptoms. Parents' willingness to participate was much higher than GP's, reflecting parents' desire for treatment. These findings underscore the need for continued therapeutic research. Careful preparation and selection of GPs and patients will be essential to ensure the feasibility of such an endeavor. TRIAL REGISTRATION: This survey study was not part of a clinical trial.

The Antiviral Effect of Berdazimer Sodium on Molluscum Contagiosum Virus Using a Novel In Vitro Methodology.

Molluscum contagiosum (MC) is characterized by skin lesions containing the highly contagious molluscum contagiosum poxvirus (MCV). MCV primarily infects children, with one US Food and Drug Administration (FDA)-approved drug-device treatment in use but no approved medications. Assessing antivirals is hindered by the inability of MCV to replicate in vitro. Here, we use vaccinia virus as a surrogate to provide evidence of the anti-poxvirus properties of berdazimer sodium, a new chemical entity, and the active substance in berdazimer gel, 10.3%, a nitric oxide-releasing topical in phase 3 development for the treatment of MC. We show that berdazimer sodium reduced poxvirus replication and, through a novel methodology, demonstrate that cells infected with drug-treated MCV virions have reduced early gene expression. Specifically, this is accomplished by studying the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-kB)-blocking protein MC160 as an example of an early gene. The results provide a plausible unique antiviral mechanism of action supporting increased MCV resolution observed in patients treated with berdazimer gel, 10.3% and describe a novel methodology that overcomes limitations in investigating MCV response in vitro to a potential new MC topical medication.

YCANTHTM (Cantharidin) Topical Solution.

YCANTHTM (cantharidin) topical solution has been approved recently for the treatment of molluscum contagiosum (MC) in children (aged ≥2 years) and adults. It works by activating serine proteases that lead to blistering and inflammation, promoting shedding of infected cells and viral clearance. In two phase-3, randomized, double-blind, vehicle-controlled trials of similar design, VP-102 (a drug-device combination, containing cantharidin 0.7% w/v and inactive ingredients, such as gentian violet, acetone, and denatonium benzoate, administered with an applicator) was investigated for the treatment of MC. VP-102 and vehicle were applied topically once every 21 days until complete clearance of lesions was observed, or for up to four treatments. Cantharidin demonstrated efficacy in achieving the primary outcome, at day 84/visit 4 (Cantharidin Application in Molluscum Patients [CAMP-1], VP-102: 46% [73/160], vehicle: 18% [19/106]; and CAMP-2, VP-102: 54% [81/150], vehicle: 13% [15/112]). Common adverse events were mild to moderate, such as lesions at the site of application, pruritus, and pain. The recommended regimen of cantharidin topical solution is its application once every 21 days until complete clearance of lesions is observed, or up to four treatments.