The Issue
Preterm birth, defined as birth before 37 weeks gestational age, is the leading cause of death for children under 5 worldwide. Globally, 1 out of 10 babies are born preterm.
While preterm birth occurs in every country, there are profound global inequalities in survival rates of babies born preterm. In low-income settings, half of all babies born before 32 weeks die due to a lack of cost-effective care (including warmth, breathing support, and infection treatment), while in high-income settings, almost all these babies survive. For babies born extremely preterm (less than 28 weeks), more than 90% of babies do not survive in low-income settings, compared to less than 10% in high-income settings. Babies who do survive are at an increased risk of cerebral palsy, autism spectrum disorders, and respiratory, visual, or auditory impairment.
While not all causes of preterm birth are well understood, the two most prominent risk factors are vaginal infections (nearly half of all preterm births can be attributed to a vaginal infection) or a diagnosed shortened cervix (which can lead to premature weakening of the cervix). There are currently no preventive or therapeutic treatment options approved by the United States Food & Drug Administration (FDA) for women at risk of preterm birth.
The Product
Scientists at the Population Council’s Center for Biomedical Research (CBR) are exploring whether Nestorone®, a potent progestin, could prevent preterm birth in women at elevated risk due to vaginal infection, shortened cervix, or a history of delivering prematurely. Progestins, including Nestorone and progesterone, work by thickening and strengthening the cervix, creating an effective barrier from infection.
Progesterone is currently used off-label in some cases to help prevent preterm birth in women with a shortened cervix, though it has limited efficacy. The superior pregestational and anti-inflammatory activity of Nestorone—which is 100 times more potent than progesterone—could help improve efficacy and reduce the amount of drug needed for administration. Nestorone could be administered either as a topical gel or via an intravaginal ring.
The Progress
CBR is currently conducting the necessary pre-clinical experiments in vivo to be able to apply for an Investigational New Drug (IND) Application prior to clinical studies. Nestorone has already been approved by the FDA for use in the Council’s one-year contraceptive vaginal system (Annovera®). Our scientists are building off the extensive safety and efficacy data of Nestorone previously generated for Annovera’s FDA approval.
In addition to testing Nestorone as a prevention option for preterm birth, our scientists are exploring whether Nestorone’s mild glucocorticoid activity could promote fetal lung development. Interrupted or incomplete lung development commonly seen in preterm babies can cause lifelong respiratory disorders, and we are investigating whether Nestorone may be able to mildly reduce the risk and/or severity of such outcomes.
The Impact
If proven effective, Nestorone could offer a promising option for women to delay or prevent preterm labor, as well as potentially reduce the risk of resulting morbidities and pulmonary issues of infants. We aim to develop an effective, safe, and affordable prevention option, aiding the health of mothers and babies worldwide.
