Primaquine in glucose-6-phosphate dehydrogenase deficiency : an adaptive pharmacometric assessment of ascending dose regimens in healthy volunteers

© 2023, Pukrittayakamee et al..

Background: Primaquine is an 8-aminoquinoline antimalarial. It is the only widely available treatment to prevent relapses of Plasmodium vivax malaria. The 8-aminoquinolines cause dose-dependent haemolysis in glucose-6-phosphate dehydrogenase deficiency (G6PDd). G6PDd is common in malaria endemic areas but testing is often not available. As a consequence primaquine is underused.

Methods: We conducted an adaptive pharmacometric study to characterise the relationship between primaquine dose and haemolysis in G6PDd. The aim was to explore shorter and safer primaquine radical cure regimens compared to the currently recommended 8-weekly regimen (0.75 mg/kg once weekly), potentially obviating the need for G6PD testing. Hemizygous G6PDd healthy adult Thai and Burmese male volunteers were admitted to the Hospital for Tropical Diseases in Bangkok. In Part 1, volunteers were given ascending dose primaquine regimens whereby daily doses were increased from 7.5 mg up to 45 mg over 15-20 days. In Part 2 conducted at least 6 months later, a single primaquine 45 mg dose was given.

Results: 24 volunteers were enrolled in Part 1, and 16 in Part 2 (13 participated in both studies). In three volunteers, the ascending dose regimen was stopped because of haemolysis (n=1) and asymptomatic increases in transaminases (n=2; one was hepatitis E positive). Otherwise the ascending regimens were well tolerated with no drug-related serious adverse events. In Part 1, the median haemoglobin concentration decline was 3.7 g/dL (range: 2.1-5.9; relative decline of 26% [range: 15-40%]). Primaquine doses up to 0.87 mg/kg/day were tolerated subsequently without clinically significant further falls in haemoglobin. In Part 2, the median haemoglobin concentration decline was 1.7 g/dL (range 0.9-4.1; relative fall of 12% [range: 7-30% decrease]). The ascending dose primaquine regimens gave seven times more drug but resulted in only double the haemoglobin decline.

Conclusions: In patients with Southeast Asian G6PDd variants, full radical cure treatment can be given in under 3 weeks compared with the current 8-week regimen.

Funding: Medical Research Council of the United Kingdom (MR/R015252/1) and Wellcome (093956/Z/10/C, 223253/Z/21/Z).

Clinical trial number: Thai Clinical Trial Registry: TCTR20170830002 and TCTR20220317004.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:12

Enthalten in:

eLife - 12(2024) vom: 06. Feb.

Sprache:

Englisch

Beteiligte Personen:

Pukrittayakamee, Sasithon [VerfasserIn]
Jittamala, Podjanee [VerfasserIn]
Watson, James A [VerfasserIn]
Hanboonkunupakarn, Borimas [VerfasserIn]
Leungsinsiri, Pawanrat [VerfasserIn]
Poovorawan, Kittiyod [VerfasserIn]
Chotivanich, Kesinee [VerfasserIn]
Bancone, Germana [VerfasserIn]
Chu, Cindy S [VerfasserIn]
Imwong, Mallika [VerfasserIn]
Day, Nicholas P J [VerfasserIn]
Taylor, Walter R J [VerfasserIn]
White, Nicholas J [VerfasserIn]

Links:

Volltext

Themen:

Antimalarials
Clinical Trial
Epidemiology
Global health
Glucose-6-phosphate dehydrogenase deficiency
Hemoglobins
Human
Journal Article
MVR3634GX1
Medicine
Primaquine
Radical cure

Anmerkungen:

Date Completed 07.02.2024

Date Revised 20.03.2024

published: Electronic

TCTR: TCTR20170830002, TCTR20220317004

Citation Status MEDLINE

doi:

10.7554/eLife.87318

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM368083357