PB0413 - Stability and Activity of Alteplase after Reconstitution in Solution

Background: Alteplase is widely used as a thrombolytic agent for restoring flow to occluded central venous access devices. According to the manufacturer, alteplase remains fully active for 24 hours at 2-8 °C and for only 8 hours at 25 °C after reconstitution in solution. Because of the worldwide shortage of alteplase, methods to store reconstituted alteplase for extended periods while maintaining its activity would be helpful.

Aims: To evaluate the stability and efficacy of alteplase after reconstitution.

Methods: Stability studies were performed according to the International Conference on Harmonization ICH Q1A(R2). Stability was determined by evaluation of pH, dynamic light scattering, size-exclusion high-performance liquid chromatography, and efficacy using the plasminogen activator-induced plasma clot lysis time assay. Briefly, clotting was induced by the addition of thrombin to recalcified plasma in the presence of reconstituted alteplase, after which clot formation and lysis were measured by turbidimetry. Sterility testing was performed using the Steritest® (Millipore, USA).

Results: Vials of 10 mg lyophilized alteplase were reconstituted to a concentration of 1 mg/mL under sterile conditions according to the manufacturer’s instructions, repackaged as 2 mL aliquots, and stored at -80°C, -20°C, 2-8°C, 21-23°C for up to 21 days, or exposed to thermal stress (40°C and 60°C). We did not observe any decrease in alteplase stability and activity at day (D) 1, D3, D7, D14 and D21 for samples stored at -80°C, -20°C, 2-8°C, and 21-23°C compared to baseline. In contrast, chemical degradation increased, and activity decreased under accelerated storage conditions (40°C and 60°C). No microbiological contamination was observed in any of the sample.

Conclusion(s): After reconstitution, alteplase can be safely aliquoted into 2 mg/2 mL syringes under good manufacturing practices and frozen or stored at low temperature. Such conditions preserve its enzymatic activity for up to 21 days.