The ongoing trials also include a cancer research UK phase I/II open label study to evaluate the safety, endocrine effects and anti-tumor activity of abiraterone acetate (CB7630) in patients with ER or AR positive advanced or metastatic breast carcinoma (clinicaltrials.gov: NCT00755885, CDR0000614059, CRUK-CR9304-21 and EUDACT-2007-003240-30). This evidence concerns the gene ESR1 and cancer.