6/30/23, 12:46 AM WARP (warfarin evaluation) Pathway Feedback Search Clinical Topics Home Studies WARP (warfarin evaluation) WARP (warfarin evaluation) Disease Disease Cancer-associated thrombosis Catheter-related thrombosis Trial question What is the role of warfarin thromboprophylaxis in cancer patients with central venous catheters? Study design Multi-center Open label RCT Population Characteristics of study participants 39.0% female N = 812 61.0% male 812 patients (313 female, 499 male) Inclusion criteria: patients aged 16 years with cancer receiving chemotherapy through central venous catheters Key exclusion criteria: contraindication to warfarin; patient on warfarin therapy, pregnancy; breastfeeding Interventions N=408 warfarin (an oral daily dose of warfarin) N=404 no warfarin (no treatment with warfarin) Primary outcome Catheter-related thrombotic events 6.0 % 6 6 4.5 % https://web.pathway.md/studies/recfTNOSNHyimOMxc 1/2 6/30/23, 12:46 AM WARP (warfarin evaluation) Pathway 3.0 % 1.5 % No significant difference 0.0 % Warfarin No warfarin No significant difference in catheter-related thrombotic events (6% vs. 6%; RR 0.99, 99% CI 0.57 to 1.72) Secondary outcomes No significant difference in thrombotic events (7% vs. 9%; RR 0.78, 95% CI 0.5 to 1.24) No significant difference in total major bleeding (1.73% vs. 0.25%; RR 6.93, 95% CI 0.86 to 56.08) No significant difference in thrombotic events and major bleeding events (9% vs. 10%; RR 0.94, 95% CI 0.61 to 1.44) Conclusion In patients aged 16 years with cancer receiving chemotherapy through central venous catheters, warfarin was not superior to no warfarin with respect to a catheter-related thrombotic events. Reference Annie M Young, Lucinda J Billingham, Gulnaz Begum et al. Warfarin thromboprophylaxis in cancer patients with central venous catheters (WARP): an open-label randomised trial. Lancet. 2009 Feb 14;373(9663):567-74. Open reference URL https://web.pathway.md/studies/recfTNOSNHyimOMxc 2/2