{"entity":{"id":"galeterone","kind":"drug","name":"Galeterone","aka":["TOK-001","VN/124-1"],"tldr":"An experimental prostate cancer tablet meant to work in men whose cancer makes a broken form of the androgen receptor. The trial designed to prove it collapsed.","summary":"Galeterone is a steroidal compound with three claimed activities against the androgen axis at once: inhibition of CYP17 lyase, direct androgen receptor antagonism, and degradation of androgen receptor protein including the constitutively active splice variant AR-V7, which lacks the ligand-binding domain and so cannot be blocked by abiraterone or enzalutamide.\n\nThat last property was the whole commercial thesis. AR-V7 detected in circulating tumour cells predicts a poor response to abiraterone and enzalutamide, so a drug that degrades the receptor rather than blocking its ligand pocket should work where they do not. Tokai Pharmaceuticals tested the thesis in ARMOR3-SV, the only phase 3 trial in prostate cancer to select men by AR-V7 status.\n\nThe trial prescreened 953 men to find 73 who were AR-V7 positive, a prevalence of 8 percent (95 percent confidence interval 6 to 10). Of those, 38 were randomised before the data monitoring committee recommended early closure: too many men progressed and left the trial before the required radiographs. Tokai stopped developing galeterone. No approval was ever sought.","status":"withdrawn","asOf":"2026-09-25","links":[{"label":"ARMOR3-SV (European Urology 2019)","url":"https://doi.org/10.1016/j.eururo.2019.08.034"},{"label":"ClinicalTrials.gov NCT02438007","url":"https://clinicaltrials.gov/study/NCT02438007"}],"tags":[],"related":[],"cancers":["prostate","prostate-mcrpc"],"sections":[],"technologies":[],"targets":["androgen-receptor","cyp17a1"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["ar-v7","arpi","castration-resistance"],"trials":["armor3-sv"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"code":"TOK-001","modality":"small molecule","mechanism":"CYP17 lyase inhibition, androgen receptor antagonism and androgen receptor protein degradation, including the AR-V7 splice variant.","approvals":[],"mechanismSteps":[],"toxicity":[],"access":[],"regulatoryEvents":[]},"route":"/drugs/galeterone/","neighbours":{"cancer":[{"id":"prostate-mcrpc","kind":"cancer","name":"Metastatic castration-resistant prostate cancer","route":"/cancers/prostate-mcrpc/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"target":[{"id":"androgen-receptor","kind":"target","name":"Androgen receptor","route":"/targets/androgen-receptor/"},{"id":"cyp17a1","kind":"target","name":"CYP17A1 (17-alpha-hydroxylase/17,20-lyase)","route":"/targets/cyp17a1/"}],"term":[{"id":"arpi","kind":"term","name":"Androgen receptor pathway inhibitor (ARPI)","route":"/terms/arpi/"},{"id":"ar-v7","kind":"term","name":"AR-V7 splice variant","route":"/terms/ar-v7/"},{"id":"castration-resistance","kind":"term","name":"Castration-resistant prostate cancer (CRPC)","route":"/terms/castration-resistance/"}],"trial":[{"id":"armor3-sv","kind":"trial","name":"ARMOR3-SV","route":"/trials/armor3-sv/"}]}}