Cabazitaxel has been given regulatory approval in the USA and is under consideration by the European Medicines Agency and other global approval committees to be used to extend life expectancy in prostate cancer patients. Prostate cancer, a cancer that forms in tissues of the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum) is common amongst older men and often goes undetected.
Actually prostate cancer is the second most common cancer in men overall. However in new findings, men who are diagnosed and have advanced cases may live up to four months longer by taking cabazitaxel. Cabazitaxel is the first drug to show a survival benefit in patients, whose disease has progressed after standard chemotherapy with docetaxel (interferes with cell division), and when all other options have been exhausted. This groundbreaking news was posted this week in The Lancet’s Cancer Special Issue.
Previously, hormone treatments were used to often reduce symptoms, but do not deter the growth of the ailment. Docetaxel radiation treatment plus prednisone is the most common prescription by doctors for this type of cancer. However, many men become resistant to docetaxel, leaving no further options and death is comes rapidly. The only option until this recent study, was to administer mitoxantrone, a type II topoisomerase inhibitor that disrupts DNA synthesis and DNA repair in both healthy cells and cancer cells, prescribed because of its beneficial effect on quality of life.
The new chemotherapy drug cabazitaxel has shown promising anti-tumour activity in patients whose cancer has progressed after docetaxel treatment.
The study’s authors say:
Cabazitaxel treatment improved median progression-free survival and time to tumour progression, and resulted in higher rates of tumour and serum prostate-specific antigen (PSA) response than did mitoxantrone.
For this finding, Johann de Bono, from the Royal Marsden NHS Foundation and The Institute of Cancer Research in the UK conducted a Phase III TROPIC trial in order to assess whether cabazitaxel improves overall survival compared with mitoxantrone in men with advanced multi-drug resistant prostate cancer and already underwent docetaxel treatment.
The study consisted of 755 patients, who were enrolled from 146 centres across 26 countries. Mitoxantrone was prescribed to 377 patients and 378 received cabazitaxel. Both were administered in combination with prednisone. The median overall survival was 15•1 months in the cabazitaxel group compared with 12•7 months in the mitoxantrone group.
However, more side effects were found in cabazitaxel patients in exchange for prolonged life. Common grade three or higher side effects such as neutropenia, a hematological disorder characterized by an abnormally low number of neutrophils, the most important type of white blood cell, in the blood was found in 82% of cabazitaxel recipients compared to 58% in mitoxantrone participants in the research. Diarrhoea as a side effect compared 6% to 1% in comparison. Finally, 28 patients taking cabazitaxel had febrile neutropenia (fever) compared with 5 taking mitoxantrone.
Johann de Bono concludes:
Cabazitaxel is the first treatment to prolong survival for metastatic multi-drug-resistant prostate cancer in the post-docetaxel setting. On the basis of these results, cabazitaxel will become a standard of care for treatment of prostate cancer in this setting.
Tanya Dorff and David Quinn from The University of Southern California, Los Angeles, USA add:
Cabazitaxel provides an added line of therapy for patients with castration-resistant prostate cancer…The horizon for patients with prostate cancer is promising…Therapeutic strategies in phase 3 testing include more potent suppression of androgen-receptor signalling, modulation of novel pathways in bone metastases (which afflict more than 90% of men with advanced prostate cancer), and increased anti-tumour immunity.
Dr Johann Sebastian de Bono FRCP, Stephane Oudard MD c, Mustafa Ozguroglu MD, Steinbjørn Hansen MD, Jean-Pascal Machiels MD, Ivo Kocak MD, Gwenaëlle Gravis MD, Istvan Bodrogi MD, Mary J Mackenzie MD, Liji Shen PhD, Martin Roessner MS, Sunil Gupta MD, A Oliver Sartor MD
The Lancet, Volume 376, Issue 9747, Pages 1147 – 1154, 2 October 2010
doi:10.1016/S0140-6736(10)61389-X
Written by Sy Kraft