Background: Furosemide is the most widely used loop diuretic in the treatment of heart failure (HF). Subcutaneous (SC) use may offer a convenient lower cost alternative to IV. Conventional furosemide solution is unsuitable for SC use because of its alkaline pH (9.0). A novel buffered furosemide formulation was developed with a pH 7.4 for use with a patch pump for self-administration. This study compares SC administration of the novel formulation with IV administration of furosemide USP. Methods: This was a randomized open-label crossover study in patients with stable HF. SC administration consisted of 80 mg (8 mg/mL in 10 mL) of the novel furosemide solution with over for 5 hours using a biphasic pattern (30 mg over 60 min followed by 12.5 mg/hour for 4 hours.). IV control consisted of 80 mg furosemide administered in two divided doses 2 hours apart. Results: A total of 16 subjects completed the study. SC administration was well tolerated. Following SC administration all participants achieved therapeutic plasma levels (600 +/- 209 ng/mL) in 30 min. Furosemide exposure was similar following IV and SC infusion administration with a mean absolute bioavailability of 99.6%. Diuresis was equivalent between the two treatments from 0-8 and 0-24 hours (Table). Conclusions: SC administration of a novel buffered furosemide injection solution results in rapid (30 min) achievement of therapeutic plasma levels and complete (100%) bioavailability as compared to IV parameters. Diuresis was equivalent (102% and 103% for 0-8h and 0-24h). SC administration of a novel furosemide formulation offers a novel delivery mode for treatment of fluid overload. SC administration with a patch pump may enable a more effective at-home treatment of HF in the pre-acute or post-acute situation and reduce the dependence on increasingly cost prohibitive ER and inpatient services. (Table Presented.).
Sica, D. D., Muntendam, P., DeBoer, R. A., & Pitt, B. (2016). Pharmacokinetic and Pharmacodynamic Response after Subcutaneous Administration of a Novel Furosemide Formulation. Journal of Cardiac Failure, 22(8), S11. https://doi.org/10.1016/j.cardfail.2016.06.041