OX51

OX51 is a sublingual formulation of **alfentanil**, a potent, short-acting synthetic opioid analgesic. Developed by **Orexo**, it utilizes the company's proprietary sublingual drug delivery technology to provide rapid onset of action and predictable duration of effect, specifically tailored for managing pain associated with short surgical or diagnostic procedures (procedural pain). Alfentanil acts primarily as an agonist at the **mu-opioid receptor**, providing rapid analgesia. OX51 was designed to offer an alternative to intravenous administration, potentially improving patient comfort and clinical workflow in outpatient settings such as clinics or diagnostic centers. However, despite completing Phase 2 clinical trials for procedures like prostate biopsies, Orexo decided to discontinue internal development to focus on other pipeline assets.

Other names

sublingual alfentanil