Patients are randomized to receive either placebo or paromomycin for 3 weeks. After the initial double-blind phase, all patients receive open-label paromomycin for 3 weeks. Following 6 weeks of therapy, patients who do not achieve a complete response receive a higher dose of paromomycin for an additional 3 weeks, while complete responders continue receiving the original dose for an additional 3 weeks. Complete or partial responders after 9 weeks may receive 16 additional weeks of optional maintenance therapy at the dose at which their response was achieved. Treatment continues for up to 25 weeks total. Patients are followed at weeks 1, 3, 4, 6, 7, and 9, and then at 2-4 week intervals.