Tinzaparin in cancer associated thrombosis beyond 6 months: TiCAT study

INTRODUCTION: The safety and efficacy of low-molecular-weight heparin (LMWH) treatment in patients with cancer-associated thrombosis (CAT) beyond 6months are unknown. Our aim was to determine the safety of long-term tinzaparin use in patients with CAT. METHODS: We performed a prospective, open, single arm, multicentre study in patients with CAT receiving treatment with tinzaparin. We evaluated the rate of clinically relevant bleeding events (major and non-major clinically relevant bleeding) and venous thromboembolism (VTE) recurrence. RESULTS: A total of 247 patients were recruited, with a crude incidence of major bleeding of 4.9% (12/247). The rate of clinically relevant bleeding during months 1-6 and 7-12, was 0.9% [95% confidence interval (95% CI) 0.5 to 1.6%] and 0.6% (95% CI 0.2 to 1.4%) (p=0.5) per patient and month, respectively. Male gender showed greater risk for clinically relevant bleeding with a hazard ratio (HR) of 2.97 (95% CI 1.01 to 8.1; p=0.02). The incidence of VTE recurrence at months 1-6 and 7-12 was 4.5% (95% CI 2.2 to 7.8%) and 1.1% (95% CI 0.1 to 3.9%), respectively. One patient died due to VTE recurrence and two because of severe bleeding. CONCLUSIONS: Treatment with tinzaparin beyond 6months is safe in patients with CAT.