Berdazimer gel improves clearance rates in phase 3 molluscum contagiosum trial

Topline data from the phase 3 B-SIMPLE4 trial showed that berdazimer 10.3% topical gel significantly improved complete lesion clearance in patients with molluscum contagiosum (MC), with outcomes favoring active treatment over vehicle at 12 weeks.^1,2

In the randomized trial of 891 patients aged 6 months and older, 32.4% of those treated with berdazimer achieved complete resolution of all lesions compared with 19.7% in the control group. The findings represent one of the largest clinical datasets evaluating a therapy for MC and support the efficacy of nitric oxide–based antiviral treatment.

Phase 3 results demonstrate improved lesion clearance

The B-SIMPLE4 study served as the pivotal trial evaluating berdazimer gel, a once-daily topical therapy designed to inhibit viral replication and enhance immune response. The primary endpoint—complete clearance of all lesions at week 12—was met with a statistically significant difference between treatment groups.

These findings were reinforced by pooled analyses from multiple randomized trials. Across studies, complete clearance rates at week 12 were approximately 30.0% with berdazimer compared with 19.8% for vehicle, with an odds ratio of 1.75 (95% CI, 1.38–2.23; P < .001).

Improvements observed across patient subgroups

Efficacy with berdazimer was consistent across demographic and clinical subgroups, including differences in age, sex, baseline lesion count, and disease duration.

Notably, in patients with atopic dermatitis—a population often associated with more persistent or widespread MC—complete clearance rates were higher with berdazimer compared with vehicle (35% vs 27.4%).

Additional analyses demonstrated reductions in lesion counts over time, with greater improvements observed in patients showing inflammatory changes associated with immune activation during treatment.

Patient-reported outcomes support clinical benefit

Beyond lesion clearance, patient-reported outcomes from the B-SIMPLE4 trial indicated meaningful clinical improvement. At week 12, “82% of participants receiving berdazimer reported substantial improvement in lesions compared to 60% in the vehicle group.”

These improvements persisted through week 24, suggesting durability of response and potential benefits beyond short-term lesion reduction.

Safety profile consistent with topical therapy

Berdazimer gel was generally well tolerated across clinical studies, with most adverse events limited to mild or moderate application-site reactions.

The most commonly reported events included application-site pain and erythema. Importantly, no systemic treatment-related adverse events were observed in the phase 3 trial, supporting minimal systemic exposure.

Clinical context and implications

Molluscum contagiosum remains a common pediatric viral skin infection, often managed with observation or procedural treatments that may be uncomfortable or difficult to implement in younger patients.

The availability of a once-daily, self-administered topical therapy with demonstrated efficacy may offer an alternative approach to care, particularly for patients seeking noninvasive treatment options.

Berdazimer’s dual mechanism—targeting viral replication while supporting host immune response—represents a shift from traditional destructive or symptomatic therapies and may influence future management strategies for MC.

References

1. Singh A, Shakeel L, Ashraf T, Goyal P, Verma A. Zelsuvmi for molluscum contagiosum: clinical evidence, mechanisms, and therapeutic significance. Ann Med Surg (Lond). 2026;88:487-491. doi:10.1097/MS9.0000000000004333

2. FDA. ZELSUVMI (Berdazimer) Topical Gel: Highlights of Prescribing Information. FDA. 2024. Accessed February 1, 2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/217424s000lbl.pdf