Topical paromomycin for New World cutaneous leishmaniasis

Area of Science:

• Dermatology
• Infectious Diseases
• Parasitology

Background:

• Cutaneous leishmaniasis (CL) is a parasitic skin disease caused by Leishmania species.
• Topical paromomycin has shown efficacy against Leishmania major in Tunisia.
• A Phase 3 trial was conducted in Panama to evaluate topical treatments against New World Leishmania species.

Purpose of the Study:

• To compare the efficacy of a combination topical cream (paromomycin-gentamicin) versus paromomycin alone for treating CL.
• To determine if the combination cream offered statistically superior cure rates for CL lesions.
• To assess the safety and tolerability of the topical treatments.

Main Methods:

• A randomized, double-blind, Phase 3 clinical trial was performed.
• 399 patients with CL lesions were randomized to receive either paromomycin-gentamicin or paromomycin alone topical cream.
• Treatment involved once-daily topical application for 20 days, with clinical cure of an index lesion as the primary endpoint.

Main Results:

• The clinical cure rate for the paromomycin-gentamicin cream was 79%.
• The clinical cure rate for the paromomycin alone cream was 78%.
• No statistically significant difference in cure rates was observed between the two treatment groups (p = 0.84). Mild to moderate dermatitis, pain, and pruritus were the most common adverse events.

Conclusions:

• The combination topical cream (paromomycin-gentamicin) did not demonstrate superiority over paromomycin alone for CL treatment in Panama.
• Both topical treatments achieved approximately 80% cure rates, consistent with previous studies in Tunisia and with parenteral antimonials.
• Topical paromomycin-based treatments remain a viable option for CL, particularly against New World Leishmania species.