Cutaneous Leishmaniasis Chronic Ulcer

A 34-year-old male soldier deployed in the Middle East presents with a 3-month history of a slowly enlarging, painless sore on the extensor forearm that began as a papule at a sandfly bite site and progressed to ulceration despite antibacterial therapy. Examination reveals a single well-defined ulcer with a raised, rounded violaceous rolled border (marked **A** in the diagram), a central adherent crust, satellite papules, and subtle nodular lymphangitis. Slit-skin smear from the ulcer edge shows intracellular amastigotes with rod-shaped kinetoplasts in dermal macrophages. PCR confirms Leishmania major. Given the size >4 cm, satellite lesions, and lymphangitic spread, which of the following is the MOST appropriate systemic treatment for this Old World cutaneous leishmaniasis?