Phase I trial of the novel taxane BMS-184476 administered in combination with carboplatin every 21 days

Update on taxane development: new analogs and new formulations

The taxanes (paclitaxel and docetaxel) represent an important class of antineoplastic agents that interfere with microtubule function leading to altered mitosis and cellular death. Paclitaxel (Taxol(®)) was originally extracted from a yew tree (Taxus spp., Taxaceae) a small slow-growing evergreen, coniferous tree. Due to the initial scarcity of paclitaxel, docetaxel (Taxotere(®)) a semisynthetic analog of paclitaxel produced from the needles of European yew tree, Taxus baccata was developed. Docetaxel differs from paclitaxel in two positions in its chemical structure and this small alteration makes it more water soluble. Today, paclitaxel and docetaxel are widely prescribed antineoplastic agents for a broad range of malignancies including lung cancer, breast cancer, prostate cancer, Kaposi's sarcoma, squamous cell carcinoma of the head and neck, gastric cancer, esophageal cancer, bladder cancer, and other carcinomas. Although very active clinically, paclitaxel and docetaxel have several clinical problems including poor drug solubility, serious dose-limiting toxicities such as myelosuppression, peripheral sensory neuropathy, allergic reactions, and eventual development of drug resistance. A number of these side effects have been associated with the solvents used for dilution of these antineoplastic agents: Cremophor EL for paclitaxel and polysorbate 80 for docetaxel. In addition, reports have linked these solvents to the alterations in paclitaxel and docetaxel pharmacokinetic profiles. In this review, we provide preclinical and clinical data on several novel taxanes formulations and analogs which are currently US Food and Drug Administration (FDA)-approved or in clinical development in various solid tumor malignancies. Of the new taxanes nab-paclitaxel and cabazitaxel have enjoyed clinical success and are FDA-approved; while many of the other compounds described in this review are unlikely to be further developed for clinical use in daily practice. Furthermore, the successful clinical emergence of novel nontaxane microtubule-targeting chemotherapy agents such as epothilones and eribulin is liable to further restrict the development of novel taxanes.

Overcoming drug efflux-based multidrug resistance in cancer with nanotechnology

Multidrug resistance (MDR), which significantly decreases the efficacy of anticancer drugs and causes tumor recurrence, has been a major challenge in clinical cancer treatment with chemotherapeutic drugs for decades. Several mechanisms of overcoming drug resistance have been postulated. Well known P-glycoprotein (P-gp) and other drug efflux transporters are considered to be critical in pumping anticancer drugs out of cells and causing chemotherapy failure. Innovative theranostic (therapeutic and diagnostic) strategies with nanoparticles are rapidly evolving and are anticipated to offer opportunities to overcome these limits. In this review, we discuss the mechanisms of drug efflux-mediated resistance and the application of multiple nanoparticle-based platforms to overcome chemoresistance and improve therapeutic outcome.

A phase I and pharmacokinetic study of novel taxane BMS-188797 and cisplatin in patients with advanced solid tumours

This phase I study investigated the maximum tolerated dose and pharmacokinetics of a 3-weekly administration of BMS-188797, a paclitaxel derivate, at three dose levels (DLs) (80, 110 and 150 mg m(-2) DL), combined with cisplatin (standard dose 75 mg m(-2)). In 16 patients with advanced malignancies treated, one patient experienced dose-limiting febrile neutropenia, sepsis and severe colitis at the 150 mg m(-2) DL; at the 110 mg m(-2) DL one episode of dose-limiting grade 3 diarrhoea/nausea occurred. Grade 3/4 haematological toxicities were leucopenia/neutropenia; grade 3 nonhaematological toxicities were neuropathy, nausea, diarrhoea and stomatits. Objective response was seen in four patients, with three complete remissions in ovarian and cervical cancer patients. Pharmacokinetics of BMS-188797 appeared linear through the 110 mg m(-2), but not through the 150 mg m(-2) DL. The mean+/-SD values for clearance, distribution volume at steady state and terminal half-life during cycle 1 were 317+/-60 ml min(-1) m(-2), 258+/-96 l m(-2) and 30.8+/-7.7 h, respectively. The maximum tolerated and recommended phase II dose for BMS-188797 was 110 mg m(-2) (1-h infusion, every 3 weeks) combined with cisplatin 75 mg m(-2).

Novel formulations of taxanes: a review. Old wine in a new bottle?

Over the past two decades, the taxanes have played a significant role in the treatment of various malignancies. However, the poor solubility of these compounds necessitates the inclusion of surfactant vehicles in their commercial formulations. Cremophor EL and polysorbate 80 have long comprised the standard solvent system for paclitaxel and docetaxel, respectively. A number of pharmacologic and biologic effects related to both of these drug formulations have been described, including clinically relevant acute hypersensitivity reactions and peripheral neuropathy. In addition, these solvents affect the disposition of intravenously administered solubilized drugs and leach plasticizers from polyvinylchloride infusion sets. A number of strategies to develop formulations of surfactant-free taxanes have been developed. They include albumin nanoparticles, polyglutamates, taxane analogs and prodrugs, emulsions, and lipsomes. An overview of these novel formulations of taxanes, their mechanisms of action, pharmacokinetics, dose and administration, adverse effects, and clinical efficacy will be discussed.

Phase II trial of the novel taxane BMS-184476 as second-line in non-small-cell lung cancer

BACKGROUND

The purpose of this study was to evaluate the tolerability and efficacy of BMS-184476, an analog of paclitaxel, in patients with advanced non-small-cell lung cancer (NSCLC) progressing or relapsing following at least one prior chemotherapy regimen.

PATIENTS AND METHODS

Fifty-six previously treated advanced NSCLC patients received BMS-184476 at a dose of 60 mg/m(2) administered intravenously over 1 h every 21 days.

RESULTS

The median number of cycles delivered per patient was five (range one to 17). Dose reduction was required in only 3.8% of cycles. Grade 4 neutropenia occurred in 19.6% of patients, but no grade 4 thrombocytopenia or anemia was reported. Febrile neutropenia was observed in only two (3.6%) patients and there were no life-threatening events. Grade 3/4 peripheral sensory-motor neuropathy was reported in 9% of patients. Other non-hematological toxicities, such as nausea and vomiting, myalgia and arthralgia, diarrhea, and mucositis, were uncommon. Partial responses were observed in eight (14.3%) patients and stable disease in 33 (58.9%). Median progression-free survival was 3.7 months [95% confidence interval (CI) 2.7-5.4] and median overall survival was 10 months (95% CI 6-13.4).

CONCLUSIONS

BMS-184476 was well tolerated at the dose of 60 mg/m(2) and showed evidence of antitumor activity in previously treated NSCLC.