Phase I study of ixabepilone, mitoxantrone, and prednisone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel-based therapy: a study of the department of defense prostate cancer clinical trials consortium.

Journal Article

Purpose

Mitoxantrone plus prednisone and ixabepilone each have modest activity as second-line chemotherapy in docetaxel-refractory castration-resistant prostate cancer (CRPC) patients. Clinical noncrossresistance was previously observed.

Patients and methods

Metastatic CRPC patients progressing during or after taxane-based chemotherapy enrolled in a phase I multicenter study of ixabepilone and mitoxantrone administered every 21 days along with prednisone. Ixabepilone and mitoxantrone doses were alternately escalated in a standard 3 + 3 design. Patients were evaluated for toxicity and disease response. Dose-limiting toxicities (DLTs) were defined as treatment related, occurring during cycle 1, and included grade 4 prolonged or febrile neutropenia, thrombocytopenia (grade 4 or grade 3 with bleeding), or > or = grade 3 nonhematologic toxicity.

Results

Thirty-six patients were treated; 59% of patients experienced grade 3/4 neutropenia. DLTs included grade 3 diarrhea (n = 1), prolonged grade 4 neutropenia (n = 4), and grade 5 neutropenic infection (n = 1). Due to prolonged neutropenia, the highest dose levels were repeated with pegfilgrastim on day 2 of each cycle. The maximum tolerated dose in combination with pegfilgrastim was not exceeded. The recommended phase II dose is mitoxantrone 12 mg/m2 and ixabepilone 35 mg/m2 every 21 days, pegfilgrastim 6 mg subcutaneously day 2, and continuous prednisone 5 mg twice per day. Thirty-one percent of patients have experienced > or = 50% prostate-specific antigen (PSA) declines, and two experienced objective responses. Of 21 patients treated with mitoxantrone 12 mg/m2 plus ixabepilone > or = 30 mg/m2, nine (43%) experienced > or = 50% PSA declines (95% CI, 22% to 66%).

Conclusion

These results suggest that the combination of ixabepilone and mitoxantrone is feasible and active in CRPC and requires dosing with pegfilgrastim.

Full Text

Duke Authors

Cited Authors

  • Rosenberg, JE; Ryan, CJ; Weinberg, VK; Smith, DC; Hussain, M; Beer, TM; Ryan, CW; Mathew, P; Pagliaro, LC; Harzstark, AL; Sharib, J; Small, EJ

Published Date

  • June 2009

Published In

Volume / Issue

  • 27 / 17

Start / End Page

  • 2772 - 2778

PubMed ID

  • 19349545

Pubmed Central ID

  • 19349545

Electronic International Standard Serial Number (EISSN)

  • 1527-7755

International Standard Serial Number (ISSN)

  • 0732-183X

Digital Object Identifier (DOI)

  • 10.1200/jco.2008.19.8002

Language

  • eng