Population Pharmacokinetics and Pharmacodynamics of Paracetamol in Malaysian Patients With Plasmodium knowlesi Malaria.

Paracetamol may improve renal function in patients with severe Plasmodium knowlesi malaria, particularly in those with acute kidney injury and hemolysis, via inhibition of cell-free hemoglobin mediated oxidative kidney damage. We developed a population pharmacokinetic/pharmacodynamic (PK/PD) model to assess effects of paracetamol on creatinine, hepatotoxicity, fever clearance, and parasite clearance among Malaysian patients with predominantly non-severe knowlesi malaria using data from the PACKNOW trial (Clinical Trials Registration: NCT03056391). A total of 372 patients were included in the PK/PD analyses (paracetamol: n = 183, control: n = 189). Paracetamol PK was described using a prior PK model published in patients with falciparum malaria. The PK/PD demonstrated that higher paracetamol exposures were associated with a faster decline in both creatinine and fever clearance time, supporting its renoprotective and antipyretic effects. Increased paracetamol exposure was not associated with hepatotoxicity or serious adverse events, despite a weak positive association with liver transaminases over time. No significant relationship was observed between paracetamol exposure and parasite clearance. Overall, these findings highlight an exposure-response relationship for paracetamol and a decline in creatinine, supporting its use as a renoprotective drug in treating Plasmodium knowlesi malaria.