{"entity":{"id":"arx517","kind":"drug","name":"ARX517","aka":["JNJ-95298177"],"tldr":"ARX517 is an experimental antibody-drug conjugate for metastatic prostate cancer, aimed at the protein PSMA. Ambrx developed it and Johnson & Johnson took it over when it bought Ambrx in 2024.","summary":"ARX517 is an antibody-drug conjugate in which a humanised anti-PSMA IgG1 antibody is covalently conjugated to two molecules of a proprietary microtubule-disrupting toxin, AS269, according to its registry record. It came to Johnson & Johnson with the acquisition of Ambrx Biopharma, announced in January 2024. The phase 1 trial (NCT04662580), now sponsored by Janssen Research & Development as ARX517/JNJ-95298177, tests it alone or with apalutamide or abiraterone in metastatic prostate cancer and is active but no longer recruiting. A second phase 1 trial (NCT07082920) combines it with JNJ-78278343. No results are recorded here.","status":"phase-1","asOf":"2026-11-03","links":[{"label":"ClinicalTrials.gov: ARX517 phase 1 (NCT04662580)","url":"https://clinicaltrials.gov/study/NCT04662580"},{"label":"ClinicalTrials.gov: JNJ-78278343 with JNJ-95298177 (NCT07082920)","url":"https://clinicaltrials.gov/study/NCT07082920"}],"tags":["pipeline","deal-asset"],"related":[],"cancers":["prostate"],"sections":[],"technologies":["adc"],"targets":["psma"],"drugs":[],"companies":["ambrx","johnson-johnson"],"institutions":[],"pathways":[],"terms":[],"trials":["nct04662580"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"provenance":{"editedBy":"OnCo gap audit (ClinicalTrials.gov v2 + company press releases)","editedOn":"2026-11-03"},"code":"JNJ-95298177","modality":"Antibody-drug conjugate (PSMA, microtubule-disrupting payload)","mechanism":"A humanised antibody against PSMA, a protein on prostate cancer cells, is joined at two sites to a microtubule-disrupting toxin called AS269, which stops the cancer cell dividing.","approvals":[],"mechanismSteps":[],"toxicity":[],"access":[],"regulatoryEvents":[]},"route":"/drugs/arx517/","neighbours":{"cancer":[{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"technology":[{"id":"adc","kind":"technology","name":"Antibody-drug conjugate (ADC)","route":"/technologies/adc/"}],"target":[{"id":"psma","kind":"target","name":"PSMA","route":"/targets/psma/"}],"company":[{"id":"ambrx","kind":"company","name":"Ambrx","route":"/companies/ambrx/"},{"id":"johnson-johnson","kind":"company","name":"Johnson & Johnson","route":"/companies/johnson-johnson/"}],"trial":[{"id":"nct04662580","kind":"trial","name":"ARX517/JNJ-95298177 as Monotherapy or Combination Therapy in Subjects With Metastatic Prostate Cancer","route":"/trials/nct04662580/"}]}}