Posology : מינונים

2 DOSAGE AND ADMINISTRATION
2.1 Recommended Vaccination

Because VYVGART causes transient reduction in IgG levels, immunization with live-attenuated or live vaccines is not recommended during treatment with VYVGART. Evaluate the need to administer age- appropriate immunizations according to immunization guidelines before initiation of a new treatment cycle with VYVGART [see Dosage and Administration (2.2) and Warnings and Precautions (5.1)].

2.2 Recommended Dose and Dose Schedules

Dilute VYVGART prior to administration. Administer via intravenous infusion only [see Dosage and Administration (2.3)].

The recommended dosage of VYVGART is 10 mg/kg administered as an intravenous infusion over one hour once weekly for 4 weeks. In patients weighing 120 kg or more, the recommended dose of VYVGART is 1200 mg (3 vials) per infusion.

Administer subsequent treatment cycles based on clinical evaluation. The safety of initiating subsequent cycles sooner than 50 days from the start of the previous treatment cycle has not been established.

If a scheduled infusion is missed, VYVGART may be administered up to 3 days after the scheduled time point.
Thereafter, resume the original dosing schedule until the treatment cycle is completed.

2.3 Preparation and Administration Instructions
Prior to administration, VYVGART single-dose vials require dilution in 0.9% Sodium Chloride Injection, USP, to make a total volume to be administered of 125 mL (see Preparation).

Check that the VYVGART solution is clear to slightly opalescent and colorless to slightly yellow. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Do not use if opaque particles, discoloration, or other foreign particles are present.
Use aseptic technique when preparing the VYVGART diluted solution for intravenous infusion. Each vial is for single-dose only.
Discard any unused portion.
Preparation
•   Calculate the dose (mg), total drug volume (mL) of VYVGART solution required, and the number of vials needed based on the recommended dose according to the patient’s body weight [see Dosage and Administration (2.2)]. Each vial contains a total of 400 mg of VYVGART at a concentration of 20 mg per mL.
•   Gently withdraw the calculated dose of VYVGART from the vial(s) with a sterile syringe and needle. Discard any unused portion of the vials.
•   Dilute the withdrawn VYVGART with 0.9% Sodium Chloride Injection, USP to make a total volume of 125 mL for intravenous infusion.
•   Gently invert the infusion bag containing the diluted VYVGART without shaking to ensure thorough mixing of the product and the diluent.
•   The diluted solution can be administered using polyethylene (PE), polyvinyl chloride (PVC), ethylene vinyl acetate (EVA), or ethylene/polypropylene copolymer bags (polyolefins bags), and with PE, PVC, EVA, or polyurethane/polypropylene infusion lines.

Storage Conditions of the Diluted Solution

•     VYVGART does not contain preservatives. Administer immediately after dilution and complete the infusion within 4 hours of dilution.
•     If immediate use is not possible, the diluted solution may be stored refrigerated at 2°C to 8°C for up to 8 hours. Do not freeze. Protect from light. Allow the diluted drug to reach room temperature before administration. Complete the infusion within 4 hours of removal from the refrigerator. Do not heat the diluted drug in any manner other than via ambient air.

Administration

•   VYVGART should be administered via intravenous infusion by a healthcare professional.
•   Visually inspect VYVGART diluted solution for particles or discoloration prior to administration. Do not use if it is discolored, or if opaque or foreign particles are seen.
•   Infuse the total 125 mL of diluted solution intravenously over one hour via a 0.2 micron in-line filter.
•   After administration of VYVGART, flush the entire line with 0.9% Sodium Chloride Injection, USP.
•   Monitor patients during administration and for 1 hour thereafter for clinical signs and symptoms of hypersensitivity reactions. If a hypersensitivity reaction occurs during administration, discontinue administration of VYVGART and institute appropriate supportive measures [see Warnings and Precautions (5.2)].
•   Other medications should not be injected into infusion side ports or mixed with VYVGART.