Pilot implementation of intermittent preventive treatment with dihydroartemisinin-piperaquine to prevent adverse birth outcomes in Papua, Indonesia: a mixed-method evaluation.

Background: A previous trial showed that intermittent preventive treatment with dihydroartemisinin-piperaquine (IPTp-DP) was more effective than the current policy of single screening and treatment in preventing malaria during pregnancy in Papua, Indonesia. The STOPMiP-2 study evaluated the Ministry of Health pilot implementation of IPTp-DP through routine antenatal care in Papua. Methods: A mixed-method evaluation was conducted in ten primary health-care facilities in the Mimika district in Papua, Indonesia from June 8, 2022, to Dec 27, 2023. Pregnant women aged 15-49 years who were HIV negative (when status known), in their second or third trimester of pregnancy, and provided written informed consent were eligible. IPTp-DP delivery effectiveness (3-day doses of three tablets [ie, nine tablets] with the first dose by directly observed therapy during antenatal care) and adherence (completion of all nine tablets, ascertained by pill count) were coprimary outcomes. Analyses were done in the modified intention-to-treat (mITT) population (defined for delivery effectiveness as all women who completed exit interviews, and for treatment adherence as all women who had a home visit). The mITT population excluded women with fever or malaria infection, those with a positive malaria test, or those who received IPTp-DP outside the designated timeframe (ie, less than 4 weeks between courses). We explored predictors of delivery effectiveness and adherence using multivariable logistic regression, and used qualitative data to provide explanatory insights. We used routine health information to assess monthly coverage by facility. This study was registered at ClinicalTrials.gov (NCT05294406) and is now complete. Findings: From June 8, 2022, to Dec 27, 2023, we enrolled 1420 pregnant women in exit interviews, of whom 1366 had data available and were eligible for the effectiveness analysis. 490 women were visited at home, of whom 484 had data available and were eligible for the adherence analysis. 556 (41%) of 1366 women had effective delivery of IPTp-DP, and among those with available data, 437 (90%) of 484 had full adherence. Predictors of full effective delivery versus partial or non-effective delivery were older maternal age (≥35 years Interpretation: Among those who received IPTp-DP, adherence to the 3-day IPTp-DP regimen was high; however, the sample size for adherence was smaller than anticipated owing to lower-than-expected full delivery effectiveness. Future studies should investigate strategies to improve treatment delivery in this setting. Funding: UK Medical Research Council.