Gilead Sciences filed European patent application EP3955921A1 covering 2-imino-5-oxo-imidazolidine inhibitors of HIV protease. The application was published by the EPO on March 25, 2026, with IPC classifications spanning A61K (medicinal preparations) and C07D (heterocyclic compounds). Designated states include all EU member states plus Iceland, Norway, and other EPC contracting states.

This is an informational patent publication with no compliance obligations or deadlines. Competitors developing generic HIV protease inhibitors should review the claims to assess potential freedom-to-operate implications. No immediate action is required, but IP legal counsel may want to monitor the prosecution of this application for claim scope developments.