Recommended dosing
The recommended weekly dose of Vivaglobin^® is 100 mg/kg to 200 mg/kg body weight administered subcutaneously. Doses may be adjusted over time to achieve the desired clinical response and serum IgG levels. As there can be differences in the half-life of IgG among patients with primary immunodeficiency (PI), the dose and dosing interval of immunoglobulin (Ig) therapy may vary.

Transitioning from IVIg
It is recommended that the patients start treatment with Vivaglobin^® one week after receiving their last regularly scheduled IVIg infusion. The initial weekly Vivaglobin^® dose can be calculated by multiplying the previous IVIg dose by 1.37, then dividing this dose into weekly doses based on the patient's previous IVIg treatment interval; for example, if IVIg was administered every three weeks, divide by 3. This dose of Vivaglobin^® will provide a systemic IgG exposure area under the curve (AUC) comparable to that of the previous IVIg treatment. Doses may be adjusted over time to achieve the desired clinical response and serum IgG levels.

As with all immune globulin (Ig) products, patients receiving Ig therapy for the first time, receiving a new product, or not having received Ig therapy within the preceding eight weeks may be at risk for developing reactions including fever, chills, nausea, and vomiting. On rare occasions, these reactions may lead to shock. Such patients should be monitored in a clinical setting during the initial administration.

Maximum dose per infusion site
In the clinical study with Vivaglobin ^®, a volume of 15 mL per infusion site was not exceeded. Doses over 15 mL were divided and infused into several sites using an infusion pump. Multiple simultaneous infusions were enabled by administration tubing and Y-site connection tubing.

Frequency of subcutaneous (Sub-Q) Ig infusions
Vivaglobin^® was administered on a weekly basis during the clinical trials. However, as there can be differences in the half-life of IgG among patients with PI, the dose and dosing interval of Ig therapy may vary. Serum IgG levels can be sampled at any time during routine weekly treatment.

Rate of Vivaglobin^®infusion
Vivaglobin^® can be infused up to 20 mL per hour.

Premedication considerations
Premedication is used in administration of IVIg to reduce systemic adverse events. Sub-Q dosing allows for a slow administration and gradual adsorption. This may prevent large, swift fluctuations in serum IgG and the adverse events that may be associated with these rapid shifts. Generally, there have been fewer reported systemic events with Sub-Q administration. No serious adverse events were reported during clinical trials. Stiehm reports using premedication in patients with prior anaphylactic reactions.¹ However, as always clinicians must weigh the risks and benefits when considering premedication for individual patients.

Reference:

1. Stiehm ER, Casillas AM, Finkelstein JZ, et al. Slow subcutaneous human intravenous immunoglobulin in the treatment of antibody immunodeficiency: use of an old method with a new product. J Allergy Clin Immunol. 1998:101:848-849.

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