NCT06191458: PBC

Postpartum Primaquine in Breast Milk

Completed Phase 4 Last updated 10 June 2025

What this trial tests

Phase 4 trial testing Primaquine in Postpartum Women in 12 participants. Completed in 23 February 2025.

Timeline

9 July 2024

Primary endpoint
23 February 2025

23 February 2025

Quick facts

Lead sponsor	University of Oxford
Phase	Phase 4
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	treatment
Enrollment	12
Start date	9 July 2024
Primary completion	23 February 2025
Estimated completion	23 February 2025
Sites	1 location across Thailand

Drugs / interventions tested

• Primaquine — full drug profile →

Conditions studied

• Postpartum Women — all drugs for Postpartum Women →

Sponsor

University of Oxford

Who can join

18 and older, female only, with Postpartum Women. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Plasmodium vivax and ovale infections both follow chronically relapsing courses, leading to cumulative morbidity and mortality. P. vivax is the second most common malaria worldwide, with an estimated 13.8 million cases annually, and there is increasing concern about severe illness and death in vulnerable populations.

Radical cure of P.vivax and P.ovale with 8-aminoquinolines is necessary to prevent relapse. The most widely 8-aminoquinoline is primaquine (7-14 day course), which has been used for almost 75 years. Its widespread use is hampered by the potentially severe haemolysis primaquine may trigger in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common red blood cell enzyme deficiency in the world. Safe administration of primaquine requires at least 30% of normal G6PD activity to avoid significant hemolysis.

Screening for malaria is routine in pregnancy, leading to improved detection of P. vivax infections, but primaquine and is contraindicated in pregnancy. As a result, relapses of P. vivax are common in postpartum and lactating women. Normal G6PD activity levels in infants less than 6 months old have only recently been described and have only been established along the Thailand-Myanmar border. Most low-resource settings are therefore unable to determine infant G6PD status. Uncertainty about infant G6PD status means that breastfeeding women are rarely offered radical cure because of theoretical concerns about drug exposure through breast milk triggering haemolysis in breastfed infants and children with G6PD deficiency. Though neonates generally have higher G6PD activity than adults, increased haemolysis for a neonate could theoretically contribute to neonatal jaundice and anaemia.

Understanding drug exposure to a breastfeeding neonate is operationally important, as interventions that can be safely offered before women leave the hospital postpartum have higher uptake. Current World Health Organization guidelines advise against prescribing primaquine to lactating women if they are breastfeeding infants less than 6 months old, or breastfeeding infants with G6PD deficiency or unknown G6PD status.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. Addressing health equity for breastfeeding women: primaquine for Plasmodium vivax radical cure.
   Abla N, Marrast AC, Jambert E, Richardson N, et al · · 2024 · cited 3× · PMID 39334094 · DOI 10.1186/s12936-024-05112-9