Determination of hydroxychloroquine and its metabolites in the breast milk of patients with autoimmune disease / 中华风湿病学杂志

ABSTRACT

Objective:To determine the concentration of hydroxychloroquine (HCQ) and its active metabolite deethylhydroxychloroquine (DHCQ) in breast milk of lactating patients with autoimmune disease. To observe the safety of hydroxychloroquine in lactation period, and to explore the factors that may affect HCQ and DHCQ concentration in the milk.Methods:Lactating patients with autoimmune disease who have taken HCQ for at least 6 months were included in our study. A new high performance liquid chromatography (HPLC) method was established to detect HCQ and DHCQ levels in breast milk. Milk samples were collected at different time points before taking the drug (0 hours), and 2 hours, 4 hours, 6 hours after taking the drug. In addition, the genotype of cytochrome CYP3A4*1G, CYP3A5*3 and CYP2D6*10 which were related to HCQ metabolism were tested by dideoxy chain termination method. Visual acuity, hearing and growth status of the patients' infants were followed up on a regular basis. T-test, one-way ANOVA and Pearson's test were used for data analysis. Results:In 15 patients, the average concentration of HCQ and DHCQ in the milk of patients taking 200 mg/d were (520±261) ng/ml and (177±112) ng/ml, respectively. While the average concentration of HCQ and DHCQ in the milk of patients taking 400 mg/d were (1 036±374) ng/ml and (397±271) ng/ml, respectively. The peak of HCQ level for 11 patients was at 4 hour after taking the drug, while the others' were at 2 hour. The breast-fed infants did not show any abnormal symptoms of hearing, vision and growth. However, cytochrome gene polymorphism did not affect the peak of HCQ and DHCQ.Conclusion:The concentration of HCQ and DHCQ in breast milk is positively correlated to the dosage. The peak level of HCQ milk is 4 hours after taking the drug. The levels of HCQ and DHCQ at 6 hours are similar as those in the whole blood. It is suggested that patients who take HCQ can feed 4 hours after taking the drug to reduce the HCQ and its active metabolites being absorbed by infants. However, the impact of HCQ on infant safety and gene polymorphism of CYP on milk concentration among individuals needs to be further verified in large sample studies and long-term follow-up.