The use of concurrent anticoagulation and emicizumab prophylaxis eliminated the need for bypassing therapy and improved a life-threatening central venous access device (CVAD)–associated thrombus in a patient with severe hemophilia A.
“Systemic anticoagulation with concomitant emicizumab has not been previously described,” Angela Weyand, MD, of the University of Michigan, Ann Arbor, and her colleagues wrote in a letter to the editor published in.
The researchers reported findings from a case of a 6-year-old boy with severe hemophilia A who developed a CVAD‐associated thrombus during immune tolerance induction with recombinant factor VIII (rFVIII). As his clinical condition worsened, the team hypothesized thrombus development was being caused by the ongoing use of bypassing therapy.
Dr. Weyand and her colleagues started prophylaxis with subcutaneous emicizumab (3 mg/kg once weekly for 4 weeks followed by 1.5 mg/kg weekly thereafter) and anticoagulation therapy (low-molecular-weight heparin given twice daily; anti‐Xa target of 0.3‐0.5 IU/ mL, later increased to 0.5‐0.7 IU/mL).
After 2 months of concurrent therapy, the team saw major symptomatic improvement and the thrombus had substantially decreased in size. One month later, his port access was removed without any bleeding complications and no further hemostatic agents were required.
“Follow‐up echocardiogram 3 months after discontinuation of anticoagulation demonstrated continued improvement with increasing organization of the thrombus,” they wrote.
Afterward, the patient was continued on emicizumab prophylaxis and did not require additional bypassing agent therapy.
“Consideration was given to surgical thrombectomy as that would be the recommendation in a non-haemophilic patient, but ultimately anticoagulation was deemed to be a safer alternative,” they wrote.
The researchers acknowledged that very little evidence is available to guide treatment of patients similar to the one described in this case. “Although this particular scenario is rare, its real‐life efficacy data in these types of settings will help inform emicizumab use, which is critical given its expanding indications,” they concluded.
No funding sources were reported. The authors reported financial disclosures related to Bayer, CSL Behring, Novo Nordisk, Octapharma, Shire, and others.
SOURCE: Weyand AC et al. Haemophilia. 2019 Mar 13. .