RESUMO
PURPOSE: Glucocorticoid receptor (GR) overexpression is associated with poor prognosis ER-negative breast cancer. GR antagonism with mifepristone increases chemotherapy-induced breast cancer cell death, therefore we conducted a phase I clinical trial of mifepristone and nab-paclitaxel in advanced breast cancer. METHODS: A novel randomized phase I design was used to assess the effect of mifepristone on nab-paclitaxel pharmacokinetics and toxicity. Patients were randomized to placebo or mifepristone for the first cycle; mifepristone was given to all for subsequent cycles. RESULTS: Nine patients were enrolled. All were found to have a twofold or greater increase in serum cortisol after mifepristone administration, reflecting effective GR inhibition. Neutropenia occurred at both nab-paclitaxel dose levels studied (100 and 80 mg/m(2)), and was easily managed with dose reduction and/or growth factor administration. Pharmacokinetic data suggest an interaction between nab-paclitaxel and mifepristone in some patients. Two patients had complete responses (CR), three partial responses (PR), one stable disease (SD), and three progressive disease (PD). Immunohistochemical staining for GR found six of nine tumors were GR-positive. All six GR-positive tumors were triple-negative at the time of recurrence. Of these six patients, two had CRs, two PRs, one SD, and one PD. CONCLUSIONS: GR appears to be a promising target in TNBC, and GR inhibition plus chemotherapy produces manageable toxicity. While neutropenia was observed in some, a nab-paclitaxel dose of 100 mg/m(2) plus mifepristone 300 mg was found to be tolerable, and a randomized phase II trial of nab-paclitaxel with/without mifepristone is planned in GR-positive advanced TNBC.
RESUMO
BACKGROUND: Recent studies suggest that carboplatin with pegylated liposomal doxorubicin (C+PLD) is as efficacious as carboplatin with paclitaxel (C+P) and possibly is more tolerable for ovarian cancer therapy. Pegylated liposomal doxorubicin (PLD) may also be efficacious and tolerable as monotherapy in recurrent or platinum-resistant disease. We performed a meta-analysis of randomized trials in order to elucidate the role of PLD in ovarian cancer. METHODS: We searched PubMed, Scopus, and ISI Web of Knowledge for studies comparing C+PLD with C+P and comparing PLD with another monotherapy. Summary hazard ratios (HRs) and relative risks with their corresponding 95% confidence intervals (CIs) were calculated using a fixed-effects model. RESULTS: Three trials were included in the doublet regimen analysis, and five trials were included in the monotherapy regimen analysis. C+PLD provided superior progression-free survival (PFS) (HR, 0.87; 95% CI, 0.78-0.96) and similar overall survival (OS; HR, 0.95; 95% CI, 0.84-1.07) compared with C+P. There was no evidence of improved tolerability: C+PLD had more gastrointestinal toxicity, anemia, thrombocytopenia, cutaneous toxicity, and mucositis/stomatitis, although there was less neutropenia, neuropathy, and alopecia. PLD monotherapy had similar PFS (HR, 0.99; 95% CI, 0.89-1.11) and OS (HR, 0.99; 95% CI, 0.88-1.11) to other monotherapies, but it was more tolerable. There was less neutropenia, anemia, thrombocytopenia, and gastrointestinal toxicity, although cutaneous toxicity was increased. CONCLUSION: C+PLD had better PFS and similar OS compared with C+P and had a very different toxicity profile. Therapy selection could be based on patient risks for side effects. PLD is as efficacious as other monotherapies and is more tolerable.