ATL-101

ATL-101 refers to two distinct investigational drugs in development by different companies for unrelated indications: 1. **ATL-101 (Atalanta Therapeutics):** A di-siRNA (divalent small interfering RNA) therapy designed to silence the HTT gene, thereby reducing production of the mutant huntingtin protein implicated in Huntington's disease. Preclinical studies in nonhuman primates demonstrated that a single intrathecal dose led to robust and durable reduction of huntingtin levels throughout the brain, including deep regions affected by Huntington’s disease, with effects lasting at least six months and an excellent safety profile[4][7][9]. The drug is being developed for central nervous system delivery using Atalanta’s proprietary di-siRNA platform. 2. **ATL 101 (Telix Pharmaceuticals/Weill Cornell/BZL Biologics):** A humanized monoclonal antibody (J591) targeting prostate-specific membrane antigen (PSMA), radiolabeled with Lutetium-177 (^177Lu). This radiopharmaceutical was developed as a targeted therapy for metastatic castration-resistant prostate cancer and other solid tumors, delivering ionizing radiation directly to PSMA-expressing tumor cells[1][3][8]. Clinical trials showed antitumor activity and manageable toxicity; however, development has been discontinued after Phase I/II studies[1].