Initial reported use of A-L for knowlesi malaria was from our retrospective study at a tertiary referral hospital in Sabah, where a small sample size of 8 out of 34 patients with PCR confirmed uncomplicated P.knowlesi infection were treated with oral artemether-lumefantrine. Median microscopic parasite clearance time was 1 day (range 0-3), which was significantly faster than those receiving chloroquine (median 2.5 days, range 1-3), while this also resulted in fewer days of hospitalization and health sector associated costs. The proportion remaining parasitaemic at day 1 was 33% 16. Our subsequent prospective study at the same site documented 109 knowlesi malaria patients successfully treated with A-L, with no recurrences identified. Unpublished data from this study showed that of the patients with uncomplicated P. knowlesi malaria enrolled, 51 received A-L monotherapy, with a median parasite clearance time of 2 days31.