Impact of Cabazitaxel (CBZ) + Prednisone (P; CBZP) on Overall Survival (OS) At 2 Yrs and in Patients (PTS) with Aggressive Disease: Post-Hoc Analyses of Tropic Trial

[Metastatic castration-resistant prostate cancer : Use of cabazitaxel taking into consideration current data]

BACKGROUND

At the 2016 ASCO annual meeting, new data from two randomized phase III studies concerning taxane-based chemotherapy as a treatment option for patients with metastatic castration-resistant prostate cancer (mCRPC) were presented.

OBJECTIVES

The focus is on the clinical impact of these data.

MATERIALS AND METHODS

A group of German experts in the field of urogenital-oncologic expertise discussed the clinical impact with respect to the current data.

RESULTS

The study results support the current clinical data. They confirm the efficacy and safety of cabazitaxel beyond first-line therapy with docetaxel for patients with mCRPC.

CONCLUSIONS

Cabazitaxel is an important treatment option after docetaxel progression. With respect to the performance status of a patient, it is adequate to reduce the dosage to 20 mg/m² cabazitaxel.

[Chemotherapy of prostate cancer]

The prognosis of patients with advanced prostate cancer has improved over the last few years. In addition to the new antihormonal treatment, chemotherapy with agents such as docetaxel and cabazitaxel has contributed to the improved prognosis. After the introduction of abiraterone and enzalutamide, conventional chemotherapy seemed to become less important but the discussion about the use of chemotherapy for hormone-sensitive prostate cancer has gained attention again. Combining docetaxel with conventional androgen deprivation therapy (ADT) improves survival compared to ADT alone. In addition, docetaxel and cabazitaxel now represent the standard for first and second line therapy in patients with castration-resistant prostate cancer.

[Metastasized prostate cancer. Position paper on the use of chemotherapy]

BACKGROUND

Antihormonal and cytotoxic therapy options are available for the therapy of metastasized prostate cancer (mPC). Because no comparative studies are available, especially for castration-resistant prostate cancer (mCRCP), it remains unclear which patients will profit best from which therapy.

OBJECTIVES

Previous data on the sequence of the various therapy options show that correct selection of the first line therapy for mCRPC can have an influence on the prognosis of the patient. In this position paper the various therapy options are critically illustrated and the clinical and pathohistological criteria for selection of the first line therapy of mCRPC are discussed.

RESULTS

Molecular markers are an important aid for future patient selection and individualized therapy for optimal use of the available forms of therapy.

Taxanes in the management of metastatic castration-resistant prostate cancer: efficacy and management of toxicity

Androgen deprivation is the therapy of choice in the majority of patients with metastatic prostate cancer. However, a state of castration resistance ultimately occurs after hormone therapy, thus defining metastatic castration-resistant prostate cancer (mCRPC). mCRPC has historically been considered a relatively chemoresistant tumor. However, due to its ability to improve survival and the quality of life in comparison with mitoxantrone, docetaxel has been established as the standard chemotherapeutic agent for first-line therapy since 2004. Moreover, recent results have shown that the novel taxane cabazitaxel is able to prolong the overall survival of patients with mCRPC previously treated with docetaxel. Even though these taxanes display a favorable toxicity profile, their routine use in clinical practice requires knowledge about the most frequent and distinct adverse events that may result from their administration.

Sequential use of novel therapeutics in advanced prostate cancer following docetaxel chemotherapy

In the last three years, five novel treatments have been shown to improve survival in metastatic castration-resistant prostate cancer (CRPC). These novel treatments have distinct mechanisms of action: tubulin-binding chemotherapy (cabazitaxel); immunotherapy (sipuleucel-T); CYP-17 inhibition (abiraterone); androgen receptor (AR) blockade (enzalutamide); and radioisotope therapy (radium-223). For a number of years, docetaxel was the only treatment with a proven survival benefit for patients with CRPC. Therefore, somewhat artificially, three treatment spaces for drug development in CRPC have emerged: pre-docetaxel; docetaxel combinations; and post-docetaxel. For patients progressing after docetaxel-based chemotherapy, treatment options available outside of clinical trials now include abiraterone, cabazitaxel and enzalutamide. Prospective data on how to best use these novel agents sequentially are not available. Clinicians face the difficult task of choosing between treatment options for individual patients to maximize patient benefit. Treatment evaluation in patients with CRPC remains challenging due to the predominance of bone metastatic disease and the lack of validated surrogate markers for survival. This review summarizes the data available with regards to sequencing of the novel treatments for CRPC.

Cabazitaxel: a guide to its use in hormone-refractory metastatic prostate cancer

The taxane derivative cabazitaxel (Jevtana(®)) is approved in the USA and the EU for use in combination with prednisone for the treatment of patients with hormone-refractory metastatic prostate cancer previously treated with a docetaxel-containing regimen. In the pivotal TROPIC trial, overall survival was significantly prolonged with cabazitaxel plus prednisone versus mitoxantrone plus prednisone in patients with metastatic castration-resistant prostate cancer who had progressed during or after docetaxel therapy. In addition, progression-free survival, the times to tumour progression and prostate specific antigen (PSA) progression, and tumour and PSA response rates were improved with cabazitaxel plus prednisone. Intravenous cabazitaxel had an acceptable tolerability profile, with haematological adverse events occurring most commonly, and diarrhoea being the most common nonhaematological adverse event.

Taxane mechanisms of action: potential implications for treatment sequencing in metastatic castration-resistant prostate cancer

CONTEXT

In the past few years, there has been a rapid increase in the number of therapies available to treat metastatic castration-resistant prostate cancer (mCRPC). Currently, approved treatments consist of the taxane class of cytotoxic drugs and androgen-targeted therapies. The challenge for clinicians is to decide the best sequence in which to give these therapies to provide the greatest benefit to their patients.

OBJECTIVE

To review recent research into the mechanism of action of taxanes in prostate cancer (PCa) cells and the clinical evidence for an interaction between taxanes and androgen-targeted therapies. The implications of these findings for clinical practice are discussed.

EVIDENCE ACQUISITION

A nonsystematic review of the relevant medical literature between 2004 and the present, in combination with clinical trial data reported at oncology meetings during 2012, was undertaken. Our perspective, focussing on the potential implications for sequencing of therapies for mCRPC, is provided.

EVIDENCE SYNTHESIS

Taxanes are shown to interact with androgen signalling in PCa cells at both the cytoplasmic level (via microtubules) and the nuclear level, affecting transcriptional regulators of androgen-responsive gene expression. Data from clinical trials suggest that androgen deprivation can potentially decrease the efficacy of taxanes in treating PCa.

CONCLUSIONS

These findings have important implications for clinical practice, and there is an urgent need for strong clinical data to support a recommendation for an optimal sequence of therapies.