Microscopic Hematuria in Patients on Tecfidera

Background: Tecfidera (dimethyl fumarate) was FDA approved for use in persons with MS in April 2013. While proteinuria was identified in 29 (8%) of patients on Tecfidera at the dose of 240 mg twice daily in the pivotal clinical trials, hematuria was not identified as an adverse event. During routine surveillance of urinalysis for patients on Tecfidera the incidental observation of microscopic hematuria was made.

Objectives: To assess the prevalence of microscopic hematuria on urinalysis while on Tecfidera.

Methods: A baseline urinalysis was obtained prior to starting Tecfidera and repeat urinalyses were obtained every 3 to 6 months while patients remained on Tecfidera.

Results: For purposes of this analysis, only patients with a known normal baseline urinalysis were included (n = 76). Patients included had no known history of renal dysfunction or hematuria. Seventy-six patients started Tecfidera with a baseline normal urinalysis. Following initiation of Tecfidera, 7 patients (9%) exhibited microscopic hematuria on at least one or more occasion that could not be attributed to another cause. Other causes included urinary tract infection, menstruation and other genitourinary causes. Microscopic hematuria was defined as the finding or 12 or more RBCs/uL. Patients with recurring hematuria were referred to nephrology for evaluation and no underlying renal pathologies were identified.

Conclusions: This small, uncontrolled, observational study suggests a possible causal association between Tecfidera and the development of microscopic hematuria.