Urinary tract infections (UTIs) were reported frequently with dalfampridine extended-release (dalfampridine-ER) 10 mg relative to placebo in previous multiple sclerosis (MS) studies.
The objective of this study was to determine whether dalfampridine-ER is associated with increased incidence of confirmed UTIs in MS patients. This post hoc analysis used UTI data from a study comparing the 4-week safety and efficacy of 5 mg (n = 144) and 10 mg (n = 142) twice-daily dalfampridine-ER versus placebo (n = 143). To confirm UTIs, three clinical assessments were used: standard urinalysis (leukocytes > 5/high-power field); urine culture (≥ 100,000 and ≥ 10,000 colony-forming units [CFUs]/mL) for those who reported UTIs as adverse events (AEs) or had positive urinalysis; and UTI symptomatology. Fisher's exact test assessed statistical significance. The proportion of patients who reported UTIs as AEs in the placebo and dalfampridine-ER 5 mg and 10 mg groups were 5.6%, 6.3%, and 9.9%, respectively. In comparison, those with laboratory-confirmed UTIs were lower: ≥ 100,000 CFUs/mL: 4.2%, 2.8%, and 2.8%; and ≥ 10,000 CFUs/mL: 4.2%, 3.5%, and 4.9%, respectively (no significant statistical difference across treatments). The proportion of patients with confirmed UTI was similar between dalfampridine-ER and placebo, thus suggesting that the treatment does not increase the risk of UTIs.
Kantor D, Chancellor MB, Snell CW, Henney Iii HR, Rabinowicz AL. Are you the author?
Neurologique Foundation, Inc., Ponte Vedra Beach, FL, USA.
Reference: Postgrad Med. 2015 Feb;127(2):218-22.