ALS-033719

ALS-033719 is a **small molecule inhibitor** that acts as a selective inhibitor of the endonuclease domain of the influenza virus A and B polymerase acidic (PA) protein. It is the **active metabolite** of the orally administered prodrug AL-794 (also known as ALS-033794 or JNJ-64155806). ALS-033719 binds to and potently inhibits the endonuclease activity of the viral polymerase, which is essential for viral RNA transcription, thereby inhibiting viral replication. The compound has shown inhibitory effects against multiple strains of influenza A and B in vitro and has been evaluated in healthy volunteers in phase 1 clinical trials to assess its safety, pharmacokinetics, and antiviral activity[1][3][5]. The primary developer associated with its clinical study is Janssen (a Johnson & Johnson company), with development history previously involving Alios BioPharma.