816: EXTENDED-USE STABILITY DATA OF ANGIOTENSIN II INFUSIONS

Introduction: Angiotensin II (Giapreza) is a parenteral vasopressor indicated for the treatment of hypotension in adults with distributive shock. Its mechanism of action differs from catecholamine vasopressors with advantages including rapid correction of hypotension, reduction in catecholamine use, fewer adverse events, and theoretical advantages surrounding kidney transplant allograft outcomes. Clinical use is limited due to cost and lack of extended stability data. Per prescribing information, dilutions should be discarded after 24 hours. This prospective in vitro study evaluated the extended use stability of diluted angiotensin II for a period of five days. Methods: We prepared angiotensin II dilutions in duplicate, by aseptically diluting 2.5 mg in 250 mL 0.9% NaCl creating a solution of 10,000 ng/mL. Admixtures were stored at room temperature (25 ± 2°C) and under refrigeration (5 ± 3°C). Stability of the dilution was assessed by: preservation of clarity, consistency of pH, and retention of concentration. Solutions were sampled at times 0, 24, 48, 72, 96, 120 hrs. Solution concentrations were sent for analysis via High Performance Liquid Chromatography (HPLC). Retention of concentration was set a priori at > 90% of initial concentration. Results: Clarity remained constant at all sample time points under both conditions. At room temperature, pH of the dilution was 5.79, ranging from 5.41 - 5.79, with a mean ± SD of 5.56 ± 0.14 and standard error of 0.06. Under refrigeration, pH of the dilution was 5.54, ranging from 5.44 - 5.56, with a mean ± SD of 0.05 and standard error of 0.02. HPLC results are forthcoming. Conclusions: Diluted angiotensin II demonstrated stability under two of the three extended storage criteria based on turbidity and pH assessments. Further information about concentration retention is needed to support extended stability. Final conclusions will be determined after final angiotensin II concentrations are reviewed and reported.