Alteplase: Stability and Bioactivity after Dilution in Normal Saline Solution

• Published in: Journal of vascular and interventional radiology Vol. 14; no. 1; pp. 99 - 102
• Main Authors: Semba, Charles P., Weck, Suzanne, Patapoff, Thomas
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 2003
• Subjects: Biological Assay; Drug Stability; Humans; Hydrogen-Ion Concentration; Plasminogen Activators - chemistry; Sodium Chloride - chemistry; Solutions; Temperature; Thrombolysis; Tissue Plasminogen Activator - chemistry; Tissue-type plasminogen activator; Thrombolysis; Tissue-type plasminogen activator
• ISSN: 1051-0443; 1535-7732
• DOI: 10.1097/01.RVI.0000052297.26939.05

To characterize the biochemical stability and bioactivity of reconstituted alteplase when diluted to a concentration of 0.01 mg/mL in normal saline solution and stored at ambient temperature for as long as 24 hours in commercial saline solution bags. Two commercially available formulations of lyophilized alteplase (2-mg and 50-mg vials, respectively) were reconstituted with sterile water to a final concentration of 1 mg/mL. For each vial configuration, 5 mg of alteplase (5 mL) was added to a commercial 500-mL bag of normal saline solution to achieve a 0.01-mg/mL targeted concentration. Solutions were assayed for optical clarity, pH, protein concentration, and in-vitro clot lysis activity. Assays of the solutions were performed at time points of 0 (control), 4, 8, and 24 hours at ambient room temperature and compared to controls. On visual inspection, aliquots of the diluted protein solutions in clear glass vials remained clear/colorless after 24 hours. Bioactivity (clot lysis assay) over the course of 24 hours at ambient temperature remained essentially unchanged relative to control (2-mg vial: mean of 98.3%, range of 93.7%–103.3%; 50-mg vial: mean of 103.1%, range of 100.6%–108.3%). The mean protein recovery rates (relative to targeted concentration) over a 24-hour period were 43% (range, 39%–46%) and 42% (range, 40%–45%) for the 2-mg and 50-mg vial configurations, respectively. Alteplase diluted in normal saline solution at a concentration of 0.01 mg/mL is biochemically stable and active at ambient temperature for as long as 24 hours as assessed by in vitro clot lysis assays. Alteplase appears to have a bimodal solubility profile in normal saline solution and further studies are required to determine the activity and solubility of alteplase concentrations lower than 0.01 mg/mL.