Evaluating the impact of HIV pre-exposure prophylaxis on pregnancy, infant, and maternal health outcomes in Malawi: PrIMO study protocol.

BACKGROUND: Incident HIV during the perinatal period significantly impedes elimination of Mother-to-Child HIV Transmission (eMTCT) efforts. Pre-Exposure Prophylaxis (PrEP) effectively reduces HIV acquisition, and new agents like injectable Cabotegravir (CAB-LA) offer potential advantages for pregnant and breastfeeding women. The Pregnancy, Infant, and Maternal health Outcomes (PrIMO) study will compare rates of composite adverse pregnancy outcomes, and infant adverse events, growth and neurodevelopment between mother-infant dyads receiving CAB-LA and those receiving oral PrEP in Malawi. METHODS: PrIMO is an observational cohort study involving: (1) the development of a PrEP Pregnancy Registry for longitudinal surveillance of pregnant women on PrEP in Malawi; and (2) the enrolment of a prospective safety cohort of 621 pregnant women initiating oral PrEP or CAB-LA and their subsequent infants. The registry will include all women continuing or initiating PrEP during pregnancy across targeted sites in Lilongwe and Blantyre districts. The safety cohort will enrol a subset of those women and their infants from Bwaila District Hospital in Lilongwe, Malawi. We hypothesize that CAB-LA's safety will be comparable to daily oral PrEP regarding adverse pregnancy outcomes, maternal/infant adverse events, and infant development. Participants in the cohort will choose either oral PrEP or CAB-LA and will be followed until 52 weeks post-delivery. Safety data will be collected from all mother-infant pairs and qualitative interviews will be conducted with a subset of purposively selected women (n = 50) to assess the acceptability of each PrEP modality. DISCUSSION: The PrIMO study will provide critical data on the safety of CAB-LA in pregnant and breastfeeding women and their infants. Results will guide clinical recommendations as the Malawi Ministry of Health prepares for the rollout of CAB-LA to this population. Evaluation of Registry implementation will inform its expansion to a nationwide safety monitoring system for PrEP use during pregnancy, with implications for similar systems in the region. TRIAL REGISTRATION NUMBER: NCT06158126. The study was prospectively registered (5 December 2023) in ClinicalTrials.gov.

Development of PainFace software to simplify, standardize, and scale up mouse grimace analyses.

ABSTRACT: Facial grimacing is used to quantify spontaneous pain in mice and other mammals, but scoring relies on humans with different levels of proficiency. Here, we developed a cloud-based software platform called PainFace ( http://painface.net ) that uses machine learning to detect 4 facial action units of the mouse grimace scale (orbitals, nose, ears, whiskers) and score facial grimaces of black-coated C57BL/6 male and female mice on a 0 to 8 scale. Platform accuracy was validated in 2 different laboratories, with 3 conditions that evoke grimacing-laparotomy surgery, bilateral hindpaw injection of carrageenan, and intraplantar injection of formalin. PainFace can generate up to 1 grimace score per second from a standard 30 frames/s video, making it possible to quantify facial grimacing over time, and operates at a speed that scales with computing power. By analyzing the frequency distribution of grimace scores, we found that mice spent 7x more time in a "high grimace" state following laparotomy surgery relative to sham surgery controls. Our study shows that PainFace reproducibly quantifies facial grimaces indicative of nonevoked spontaneous pain and enables laboratories to standardize and scale-up facial grimace analyses.