Paracetamol Effect on Oxidative Stress and Renal Function in Severe Malaria

Summary

Blackwater fever, characterized by intravascular haemolysis and hemoglobinuria, is an important cause of renal impairment and mortality in severe malaria caused by Plasmodium falciparum. The largest malaria clinical trials report blackwater incidences of 5-7% in Asian adults and 4% in African children with severe malaria treated with artesunate or quinine. The prevalence of blackwater fever in Chittagong, Bangladesh is 15% with associated rates of renal failure and mortality of 42.9% and 14.2% respectively.

The fundamental characteristic of blackwater fever is the presence of intravascular hemolysis of both infected and uninfected erythrocytes and release of free haemoglobin. The cytotoxic free haemoglobin present can cause severe oxidative damage as a result of haem redox cycling yielding ferric and ferryl heme, which generate radical species that induce lipid peroxidation and subsequent production of F2-isoprostanes (F2-IsoPs). Evidence suggests that F2-IsoPs generated by the hemoprotein-catalyzed oxidation of lipids are responsible for the oxidative damage and vasoconstriction associated with renal injury in haemolytic disorders and rhabdomyolysis.

A novel mechanism of paracetamol was recently demonstrated, showing that paracetamol is a potent inhibitor of hemoprotein-catalyzed lipid peroxidation by reducing ferryl heme to its less toxic ferric state and quenching globin radicals. In a recent proof of concept trial, paracetamol at therapeutic levels was shown to significantly decrease oxidant kidney injury, improve renal function and reduce renal damage by inhibiting the hemoprotein-catalyzed lipid peroxidation in a rat model of rhabdomyolysis-induced renal injury. Since adults with severe malaria demonstrate increased concentrations of cell-free haemoglobin, and urinary F2-IsoPs, the investigators hypothesize that this novel inhibitory mechanism of paracetamol may provide renal protection in this population by reducing the hemoprotein-induced lipid peroxidation. As there is currently no consensus that exists concerning adequate medical treatment for blackwater fever, the potential application of this safe and extensively used drug would be of great benefit.

Conditions

• Malaria

Interventions

DRUG

Paracetamol

\>50kg: Paracetamol 1gm PO/NG q6hourly for 72hours and afebrile for 24h (maximum total dose 4g/24 hours) plus intravenous Artesunate \<50kg: Paracetamol 12.5-15mg/kg/dose q6hourly for 72hours and afebrile for 24h (maximum total dose 5 doses/24hours;75mg/kg) plus intravenous Artesunate

DRUG

No Paracetamol

No paracetamol + Intravenous Artesunate * If temperature \> 40°C, ibuprofen PO/PR will be administered in the absence of renal impairment and dehydration; 500mg paracetamol PO/PR will be administered in the presence of renal impairment or dehydration. Dengue testing will be done prior to the administration of ibuprofen.

Sponsors & Collaborators

• University of Oxford

  lead OTHER

Principal Investigators

• Katherine Plewes, MD · University of Oxford

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

12 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2012-07-10

Primary Completion

2014-09-13

Completion

2014-09-21

Countries

• Bangladesh

Study Locations