Clinical and population-based study design considerations to accelerate the investigation of new antiretrovirals during pregnancy

Guidelines for tuberculosis screening and preventive treatment among pregnant and breastfeeding women living with HIV in PEPFAR-supported countries

BACKGROUND

Tuberculosis (TB) preventive treatment (TPT) is recommended by the World Health Organization (WHO) for persons living with HIV, including pregnant and breastfeeding women. Given the President's Emergency Plan for AIDS Relief (PEPFAR)'s investment in TPT services for persons living with HIV as a strategy to prevent TB as well as uncertainty in guidelines and policy regarding use of TPT during pregnancy and the postpartum period, we conducted a review of current relevant national guidelines among PEPFAR-supported countries.

METHODS

Our review included 44/49 PEPFAR-supported countries to determine if TB screening and TPT are recommended specifically for pregnant and breastfeeding women living with HIV (WLHIV). National guidelines reviewed and abstracted included TB, HIV, prevention of vertical HIV transmission, TPT, and any other relevant guidelines. We abstracted information regarding TB screening, including screening tools and frequency; and TPT, including timing, regimen, frequency, and laboratory monitoring.

RESULTS

Of 44 PEPFAR-supported countries for which guidelines were reviewed, 66% were high TB incidence countries; 41% were classified by WHO as high TB burden countries, and 43% as high HIV-associated TB burden countries. We found that 64% (n = 28) of countries included TB screening recommendations for pregnant WLHIV in their national guidelines, and most (n = 35, 80%) countries recommend TPT for pregnant WLHIV. Fewer countries included recommendations for breastfeeding as compared to pregnant WLHIV, with only 32% (n = 14) mentioning TB screening and 45% (n = 20) specifically recommending TPT for this population; most of these recommend isoniazid-based TPT regimens for pregnant and breastfeeding WLHIV. However, several countries also recommend isoniazid combined with rifampicin (3RH) or rifapentine (3HP).

CONCLUSIONS

Despite progress in the number of PEPFAR-supported countries that specifically include TB screening and TPT recommendations for pregnant and breastfeeding WLHIV in their national guidelines, many PEPFAR-supported countries still do not include specific screening and TPT recommendations for pregnant and breastfeeding WLHIV.

Pharmacokinetic Evaluation in Pregnancy-Current Status and Future Considerations: Workshop Summary

As pregnant individuals have traditionally been excluded from clinical trials, there is a gap in knowledge at the time of drug approval regarding safety, efficacy, and appropriate dosing for most prescription medications used during pregnancy. Physiologic changes in pregnancy can result in changes in pharmacokinetics that can impact safety or efficacy. This highlights the need to foster further research and collection of pharmacokinetic data in pregnancy to ensure appropriate drug dosing in pregnant individuals. Therefore, the US Food and Drug Administration and the University of Maryland Center of Excellence in Regulatory Science and Innovation hosted a workshop on May 16 and 17, 2022, titled "Pharmacokinetic Evaluation in Pregnancy." This is a summary of the workshop proceedings.

Surveillance of ARV safety in pregnancy and breastfeeding: towards a new framework

Introduction

As new antiretrovirals (ARVs), including long‐acting ARVs for treatment and prevention, are approved and introduced, surveillance during pregnancy must become the safety net for evaluating birth outcomes, especially those that are rare and require large numbers of observations. Historically, drug pharmacovigilance in pregnancy has been limited and fragmented between different data sources, resulting in inadequate data to assess risk. The International Maternal Pediatric Adolescent AIDS Clinical Trials Network and World Health Organization convened a Workshop which reviewed strengths and weaknesses of existing programs and discussed an improved framework to integrate existing safety data sources and promote harmonization and digitalization.

Discussion

This paper highlights that although robust sources of safety data and surveillance programs exist, key challenges remain, including unknown denominators, reporting bias, under‐reporting (e.g. in voluntary registries), few data sources from resource‐limited settings (most are in North America and Europe), incomplete or inaccurate data (e.g. within routine medical records). However, recent experiences (e.g. with safety signals) and current innovations (e.g. electronic record use in resource‐limited settings and defining adverse outcomes) provide momentum and building blocks for a new framework for active surveillance of ARV safety in pregnancy. A public health approach should be taken using data from existing sources, including registries of pregnancy ARV exposure and birth defects; observational surveillance and cohort studies; clinical trials; and real‐world databases. Key facilitators are harmonization and standardization of outcomes, sharing of materials and tools, and data linkages between programs. Other key facilitators include the development of guidance to estimate sample size and duration of surveillance, ensuring strategic geographic diversity, bringing partners together to share information and engaging the community of women living with HIV.

Conclusions

Looking ahead, critical steps to safely introduce new ARVs include (1) adopting harmonized standards for measuring adverse maternal, birth and infant outcomes; (2) establishing surveillance centres of excellence in areas with high HIV prevalence with harmonized data collection and optimized electronic health records linking maternal/infant data; and (3) creating targets and evaluation goals for reporting progress on implementation and quality of surveillance in pregnancy. The platform will be leveraged to ensure that appropriate contributions and strategic actions by relevant stakeholders are implemented.

Accelerating investigation of new HIV drugs in pregnancy: advancing the research agenda from theory to action

Introduction

Historical approaches to clinical development of novel therapeutics for treatment and prevention of HIV have led to unacceptable delays in the generation of data to support optimal antiretroviral drug use in pregnancy. Over the last 5 years, multiple stakeholders have voiced their concerns around the exclusion of pregnant women from drug trials, and some progress has been made to consolidate principles and forge consensus. Building on ongoing efforts, the World Health Organization (WHO) and the International Maternal Paediatric Adolescent AIDS Clinical Trials Network (IMPAACT) convened a technical consultation designed to move the discussion from theory to practice.

Discussion

Accelerating the inclusion of pregnant women in pre‐licensure clinical trials, with a goal to have pharmacokinetics (PK) and preliminary safety data for all new HIV agents in pregnancy available at the time of drug approval, requires: (1) performing non‐clinical developmental and reproductive toxicology studies early in drug development for all new HIV agents; (2) recognizing and acting on the central role of women of childbearing potential affected by HIV through the research being conducted and the dissemination of associated results; (3) enrolling pregnant women in studies to specifically determine pregnancy PK and preliminary safety, as soon as late non‐clinical studies are completed with no negative signals, for all new HIV agents that have demonstrated preliminary evidence of safety and efficacy from phase 2 trials; (4) investigating adverse pregnancy and birth outcomes through dedicated pregnancy safety studies for all new priority HIV agents; and (5) expanding active surveillance of drug safety in pregnancy for rare events, such as birth defects.

Strategic actions to pursue include developing tools and resources to support designing and implementing studies among pregnant and breastfeeding women, identifying and promoting modifications of the regulatory framework that are supportive of systematic ethical investigation of new drugs in pregnancy, coordinating surveillance efforts, mobilizing key stakeholders and promoting transparency and accountability for all involved.

Conclusions

With more than 19 million women living with HIV worldwide, ensuring greater inclusion of pregnant women in research on novel therapeutics is a priority to support drug optimization and effective introduction of innovations for treatment and prevention of HIV.