{"entity":{"id":"ratio-therapeutics","kind":"company","name":"Ratio Therapeutics","aka":[],"tldr":"Ratio Therapeutics, of Boston, designs small molecules that carry a radioactive isotope to fibroblast activation protein, a protein on the supporting tissue of sarcomas and other solid tumours, so radiation is delivered from inside the body. Its lead, an actinium-225 radioligand, is in the ATLAS phase 1/2 trial in advanced sarcomas.","summary":"Ratio Therapeutics is a clinical-stage Boston radiopharmaceutical company whose Trillium targeting scaffold combines pharmacokinetic modulation with chelation chemistry to create small-molecule radioligands that can be paired with imaging or therapeutic isotopes (theranostics). The lead programme [Ac-225]RTX-2358 is a fibroblast activation protein (FAP)-targeted actinium-225 therapeutic in the ATLAS phase 1/2 trial in advanced sarcomas; the pipeline also includes a next-generation GRPR programme and additional mono- and bispecific radioligands, with a fifth IND filing in preparation. In July 2026 Ratio closed a USD 70 million Series C with Duquesne Family Office, Bristol Myers Squibb, Catalio Capital, Eli Lilly and Wasatch Group, taking total capital raised above USD 240 million. It has manufacturing collaborations with PharmaLogic, an actinium-225 supply agreement with PanTera (June 2026) and, in September 2026, a research collaboration and licence agreement with RayzeBio.","asOf":"2026-09-10","links":[{"label":"Official website","url":"https://ratiotx.com/"},{"label":"Series C press release","url":"https://ratiotx.com/2026/07/31/ratio-therapeutics-closes-70-million-series-c-financing-to-advance-clinical-development-of-targeted-radiotherapeutics-pipeline-and-expand-manufacturing-infrastructure/"},{"label":"News","url":"https://ratiotx.com/news1/"}],"tags":[],"related":[],"cancers":["sarcoma"],"sections":["radiopharma"],"technologies":["radioligand-therapy","targeted-alpha-therapy"],"targets":["fap"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Earlier rounds (Series A and B) not fetched and omitted."],"hq":"Boston, MA","country":"US","companyType":"radiopharma","website":"https://ratiotx.com/","stage":"growth","investors":[],"funding":[{"round":"Series C","year":2026,"amountUsd":70000000,"source":"https://ratiotx.com/2026/07/31/ratio-therapeutics-closes-70-million-series-c-financing-to-advance-clinical-development-of-targeted-radiotherapeutics-pipeline-and-expand-manufacturing-infrastructure/","note":"Brings total capital raised to over USD 240 million"}]},"route":"/companies/ratio-therapeutics/","neighbours":{"cancer":[{"id":"sarcoma","kind":"cancer","name":"Sarcomas (soft tissue, bone, GIST)","route":"/cancers/sarcoma/"}],"section":[{"id":"radiopharma","kind":"section","name":"Radiopharmaceuticals & Theranostics","route":"/fronts/radiopharma/"}],"technology":[{"id":"radioligand-therapy","kind":"technology","name":"Radioligand therapy (beta emitters)","route":"/technologies/radioligand-therapy/"},{"id":"targeted-alpha-therapy","kind":"technology","name":"Targeted alpha therapy","route":"/technologies/targeted-alpha-therapy/"}],"target":[{"id":"fap","kind":"target","name":"FAP","route":"/targets/fap/"}]}}