A 32-year-old man from rural Maharashtra presents with hypopigmented macules on his face and trunk for 6 months. Slit-skin smear shows 4+ acid-fast bacilli. He is started on multidrug therapy (MDT) for lepromatous leprosy. After 2 weeks of treatment with rifampicin, dapsone, and clofazimine, he develops acute hemolytic anemia with jaundice, dark urine, and reticulocytosis of 12%. His baseline G6PD status was not checked. Which antileprotic agent is most likely responsible for this adverse effect?