Preclinical profile of cabazitaxel

First-generation taxanes have changed the treatment paradigm for a wide variety of cancers, but innate or acquired resistance frequently limits their use. Cabazitaxel is a novel second-generation taxane developed to overcome such resistance. In vitro, cabazitaxel showed similar antiproliferative activity to docetaxel in taxane-sensitive cell lines and markedly greater activity in cell lines resistant to taxanes. In vivo, cabazitaxel demonstrated excellent antitumor activity in a broad spectrum of docetaxel-sensitive tumor xenografts, including a castration-resistant prostate tumor xenograft, HID28, where cabazitaxel exhibited greater efficacy than docetaxel. Importantly, cabazitaxel was also active against tumors with innate or acquired resistance to docetaxel, suggesting therapeutic potential for patients progressing following taxane treatment and those with docetaxel-refractory tumors. In patients with tumors of the central nervous system (CNS), and in patients with pediatric tumors, therapeutic success with first-generation taxanes has been limited. Cabazitaxel demonstrated greater antitumor activity than docetaxel in xenograft models of CNS disease and pediatric tumors, suggesting potential clinical utility in these special patient populations. Based on therapeutic synergism observed in an in vivo tumor model, cabazitaxel is also being investigated clinically in combination with cisplatin. Nonclinical evaluation of the safety of cabazitaxel in a range of animal species showed largely reversible changes in the bone marrow, lymphoid system, gastrointestinal tract, and male reproductive system. Preclinical safety signals of cabazitaxel were consistent with the previously reported safety profiles of paclitaxel and docetaxel. Clinical observations with cabazitaxel were consistent with preclinical results, and cabazitaxel is indicated, in combination with prednisone, for the treatment of patients with hormone-refractory metastatic prostate cancer previously treated with docetaxel. In conclusion, the demonstrated activity of cabazitaxel in tumors with innate or acquired resistance to docetaxel, CNS tumors, and pediatric tumors made this agent a candidate for further clinical evaluation in a broader range of patient populations compared with first-generation taxanes.

Cabazitaxel (jevtana): a novel agent for metastatic castration-resistant prostate cancer

OBJECTIVE

This article presents current clinical evidence supporting the use of cabazitaxel (Jevtana) in men with metastatic castration-resistant prostate cancer (mCRPC).

DATA SOURCES

We conducted a literature search using abstracts from MEDLINE and PubMed (from January 1966 to December 2011) and the American Society of Clinical Oncology (from January 2000 to December 2011). The search included clinical studies and abstracts in the English language that described the pharmacology, pharmacokinetics, clinical activity, and safety of cabazitaxel in mCRPC.

RESULTS

Cabazitaxel, a semisynthetic microtubule inhibitor that induces cell death by microtubule stabilization, was approved in combination with prednisone for the treatment of mCRPC in patients who had been treated with a docetaxel-(Taxotere)-containing regimen. The approval of this taxane derivative was based primarily on the results of a randomized, open-label trial in patients with mCRPC who were treated with either cabazitaxel 25 mg/m(2) or mitoxantrone (Novantrone) 12 mg/m(2) intravenously every 3 weeks, both in combination with prednisone 10 mg/day. The median survival period was 15.1 months with cabazitaxel and 12.7 months with mitoxantrone. Neither group experienced complete responses. Cabazitaxel has also shown activity in breast cancer and other malignancies. In clinical trials, common grade 3 or grade 4 adverse reactions were myelosuppression, febrile neutropenia, diarrhea, fatigue, and asthenia. Other adverse effects included abdominal pain, back pain, arthralgia, and peripheral neuropathy.

CONCLUSION

Cabazitaxel appeared to be an effective second-line agent in patients with mCRPC refractory to a docetaxel-containing regimen. Studies comparing cabazitaxel with existing first-line regimens for mCRPC are under way. Until the results of these head-to-head trials are published, it remains uncertain whether cabazitaxel is more effective or more tolerable than the currently available first-line regimens.