Fosbretabulin tromethamine in the treatment of thyroid cancer

ABSTRACT

Introduction: Anaplastic thyroid carcinoma [ATC] is a rare, highly aggressive neoplasm with a disease-specific mortality of nearly 100%. Available treatment options include surgery, radiotherapy, chemotherapy or their combination and, more often recently, participation in clinical trials, as recommended by all available guidelines. However, despite of many attempts with the use of new targeted drugs, to date no remarkable progress in the improvement in patients’ survival has been made. Fosbretabulin (combretastatin A4 phosphate, CA4P) is a vascular disrupting agent, and a new drug that targets tumor neovasculature leading to an acute, reversible reduction in tumor blood flow and tumor central necrosis. Its activity against ATC was evaluated in the FACT trial.

Areas covered: Published results of preclinical, phase I and II studies, and other reports evaluating the mechanism of action, efficacy and safety of fosbretabulin alone or combination with other drugs in ATC are evaluated.

Expert Opinion: Disappointing results of previous randomized studies, referred to ATC treatment, force us to draw conclusions. Among the reasons leading to the failure of FACT study was an insufficient number of enrolled patients. Since available guidelines emphasized the necessity to treat ATC under clinical trials, inclusion criteria should be reconsidered to make the recruitment process much easier and faster in future.

KEYWORDS:

• Fosbretabulin
• combretastatin A4 phosphate
• CA4P
• anaplastic thyroid cancer

Declaration of interest

The preparation of this review was not supported by any external funding. Dr. Krajewska has participated in a Bayer HealthCare Pharmaceuticals Advisory Board. Prof. Jarzab has participated in AstraZeneca and Sobi Advisory Boards and has received honoraria from Sanofi, Ipsen, Novartis, Pfizer, Bayer HealthCare Pharmaceuticals, Roche, Eisai, Oxigene and Exelixis. Both authors participated in FACT trial. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.