As an IgG1 monoclonal antibody targeting Claudin 18.2 (CLDN18.2), zolbetuximab plays a crucial role in the treatment of advanced or metastatic gastric cancer positive for CLDN18.2. The process of preparing its pharmaceutical formulations must strictly comply with specific standards and precautions.
Precautions for Zolbetuximab
The following is a detailed introduction to the precautions for zolbetuximab.
1. Reconstitution Steps and Precautions
Reconstitution of zolbetuximab is the first step in preparing the pharmaceutical formulation. During the reconstitution process, 5.0 mL of water for injection specified in the Japanese Pharmacopoeia must be used to ensure the purity and quality of the drug. When reconstituting, the water for injection should be slowly injected along the inner wall of the zolbetuximab vial. Shaking is not allowed; instead, the solution should be gently stirred until it is completely dissolved. This step is intended to prevent excessive air bubbles or foam from forming during reconstitution, which could affect the stability and concentration of the drug.
After reconstitution, the solution must be allowed to stand to let air bubbles in the vial disappear. Throughout the entire process, direct sunlight exposure should be avoided, as it may cause the drug to decompose or deteriorate, thereby affecting its efficacy.
The reconstituted solution should be a clear liquid ranging from colorless to slightly yellow. If turbidity or precipitation occurs, the solution must not be used.
2. Dilution Steps and Precautions
After successful reconstitution, the next step is to dilute zolbetuximab. Draw the required volume of the reconstituted solution from the vial and add it to an intravenous infusion bag containing normal saline, adjusting the final concentration to 2.0 mg/mL. During the dilution process, the infusion bag should be gently inverted to mix the solution, avoiding foaming. Direct sunlight exposure must also be avoided throughout the dilution process to ensure the stability of the drug.
After dilution, a visual inspection should be conducted to check for the presence of particles in the liquid. Particles may be impurities generated during reconstitution or dilution, or contaminants introduced into the solution. If particles are found, the diluted solution must not be used to avoid unnecessary risks to the patient.
The diluted drug should be used promptly. Under room temperature conditions, the diluted drug must be administered within 6 hours to ensure its activity and stability. If storage of the diluted drug is necessary, it should be stored at 2-8°C and used as soon as possible within 24 hours after dilution. Any unused residual solution should be discarded promptly and must not be reused.
