Background: Venous thromboembolism (VTE) is a well-known complication in adults receiving asparaginase (ASP) for acute lymphoblastic leukemia (ALL). We previously reported 27.3% VTE rate in patients (pts) receiving a modified Dana Farber Cancer Institute (DFCI) intensification phase. Low-dose enoxaparin (ENOX) was not associated with lower rate of VTE. We describe escalated dose of ENOX in adults treated with this protocol. Methods: 38 pts with ALL treated with a weekly ASP-based modified DFCI intensification for 21-30 weeks, received ENOX 1 mg/kg subcutaneously daily (adjusted-dose group).The result was compared with a similar group of 41 pts receiving ENOX 40 mg for pts weighing < 80 kg, or 60 mg for pts ≥ 80 kg (low-dose group), and to a historical cohort of 99 pts treated with the same protocol, without prophylaxis. Results: There was no significant difference among groups with respect to median age, weight and number of cycles. The actual mean dose of ENOX in the low-dose group was 0.62 mg/kg, as compared to 0.84 mg/kg in the adjusted-dose group. No major bleeding complications were observed. Minor bleeding rate was 5%.VTE rate in the entire cohort was 22.7%.VTE rate in pts receiving adjusted dose ENOX was 18%, as compared to 26.8% in the low-dose group. There was no significant difference in the VTE rate according to age or gender. Sites of VTE in the prophylaxis groups included lower extremity (9), sagittal sinus (3), central line related (5) and pulmonary embolism (8); some pts had > 1 site. Conclusions: Prophylactic ENOX during intensification in adults with ALL was safe: despite dose increase to 1 mg/kg, no increase in bleeding events was observed. There was trend toward a lower rate of VTE with 1 mg/kg ENOX, particularly in patients weighing ≥ 80 kg; however, a larger cohort is needed to determine if the difference is significant.

*Comparing low dose vs adjusted dose