Avantor (AVTR) said Tuesday it has expanded its NuSil brand partnership with the Population Council to support the development of a three-month dapivirine vaginal ring for HIV prevention.

NuSil will supply high-purity silicones for the long-acting vaginal ring, which is designed to provide up to three months of HIV prevention, Avantor said.

The extended-duration ring is expected to improve convenience, lower annual costs and expand access, particularly in regions with high HIV prevalence among women, according to the company.

The Population Council submitted the three-month ring for regulatory review by the European Medicines Agency in November 2025 and plans to seek approvals in sub-Saharan Africa and other regions, Avantor said.