{"entity":{"id":"mt-303","kind":"drug","name":"MT-303","aka":[],"tldr":"MT-303 is an experimental in vivo CAR therapy from CREATE Medicines, in phase 1 trials for liver cancer (hepatocellular carcinoma).","summary":"MT-303 is an in vivo CAR therapy: mRNA in lipid nanoparticles that programmes myeloid cells from CREATE Medicines. Messenger RNA in lipid nanoparticles makes the patient's own myeloid cells, in the blood and inside the tumour, carry a chimeric antigen receptor against GPC3. The phase 1 study NCT06478693 is recruiting people with hepatocellular carcinoma, including a first-line group given MT-303 with atezolizumab and bevacizumab (first patient dosed, announced December 2025). The registry still names the sponsor by the company's former name, Myeloid Therapeutics. Whether it works in people has not been established.","status":"phase-1","asOf":"2026-11-04","links":[{"label":"CREATE Medicines","url":"https://createmedicines.com/"},{"label":"CREATE Medicines release on first-line HCC dosing, December 2025","url":"https://www.biospace.com/press-releases/create-medicines-doses-first-patient-in-frontline-hcc-trial-evaluating-mt-303-an-in-vivo-car-therapy-in-combination-with-standard-of-care-immunotherapy"},{"label":"ClinicalTrials.gov NCT06478693","url":"https://clinicaltrials.gov/study/NCT06478693"}],"tags":["pipeline","ctgov-ingest"],"related":[],"cancers":["hcc"],"sections":[],"technologies":[],"targets":["gpc3"],"drugs":[],"companies":["create-medicines"],"institutions":[],"pathways":[],"terms":[],"trials":["nct06478693"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"provenance":{"editedBy":"OnCo startup monitors, investor portfolios (company pipeline pages and ClinicalTrials.gov v2)","editedOn":"2026-11-04"},"code":"MT-303","modality":"In vivo CAR therapy: mRNA in lipid nanoparticles that programmes myeloid cells","mechanism":"Messenger RNA in lipid nanoparticles makes the patient's own myeloid cells, in the blood and inside the tumour, carry a chimeric antigen receptor against GPC3.","approvals":[],"mechanismSteps":[],"toxicity":[],"access":[],"regulatoryEvents":[]},"route":"/drugs/mt-303/","neighbours":{"cancer":[{"id":"hcc","kind":"cancer","name":"Hepatocellular carcinoma","route":"/cancers/hcc/"}],"target":[{"id":"gpc3","kind":"target","name":"Glypican-3","route":"/targets/gpc3/"}],"company":[{"id":"create-medicines","kind":"company","name":"CREATE Medicines","route":"/companies/create-medicines/"}],"trial":[{"id":"nct06478693","kind":"trial","name":"A Study of MT-303 in Adults With Advanced or Metastatic GPC3-Expressing Cancers, Including HCC","route":"/trials/nct06478693/"}]}}