Pharmacological Class:
Immune globulin.

Active Ingredient(s):
Varicella zoster immune globulin (human) 125 IU; per vial; lyophilized pwd for IM inj after reconstitution; contains <250mg of total protein (mostly human IgG), <40mcg/mL of IgA; preservative- and mercury-free.

Company
Cangene Corporation
Indication(s):
Postexposure prophylaxis of varicella in high risk individuals (include immunocompromised children and adults, newborns of mothers with varicella shortly before or after delivery, premature infants, neonates and infants <1 year old, adults without evidence of immunity, pregnant women). To reduce severity of varicella.

Pharmacology:
Varizig provides passive immunization for non-immune individuals exposed to varicella zoster virus (VZV), reducing the severity of varicella infections.

Clinical Trials:
A randomized, open-label, multi-center, active controlled clinical trial was conducted in 60 pregnant women without immunity to VZV as confirmed by latex agglutination test. Patients were stratified on the basis of time from first exposure to varicella: 1–4 days post-exposure and 5–14 days post-exposure. The women were randomized into one of three study arms as follows: (1) single Varizig 125 IU/10kg IV dose to max dose of 625 IU, (2) single Varizig 125 IU/10kg IM dose to max dose of 625 IU, or (3) single VZIG (comparator product) 125 IU/10kg IM dose to max dose of VZIG 625 IU. Patients were followed for 42 days.

Incidence of clinical varicella was similar across all treatment groups with an overall incidence of 33%; however, in the subset of 28 subjects with more than 24 hours exposure to varicella, the incidence of clinical varicella in the combined treatment groups was 64%.

Mean weighted constitutional illness scores (CIS) (6) were similar across all groups and none of the subjects has serious complications of varicella. The small number of subjects in each treatment stratum and the lack of agreed upon pre-specified hypothesis testing precluded formal statistical comparisons between groups.

Legal Classification:
Rx

Contraindication(s):
IgA-deficiency with IgA antibodies and history of hypersensitivity. Previous severe reaction to human immune globulin.

Adults & Children:
See full labeling. Administer one single-dose by IM inj ideally within 96 hours of exposure. Based on patient size: divide dose and give in ≥2 inj sites; max 3mL per inj site. Inject into deltoid muscle or anterolateral aspects of the upper thigh. Avoid gluteal region; if needed, only use upper, outer quadrant. ≤2kg: 62.5 IU; 2.1–10kg: 125 IU; 10.1–20kg: 250 IU; 20.1–30kg: 375 IU; 30.1–40kg: 500 IU; ≥40.1kg: 625 IU. Consider 2nd full dose for high risk patients with additional exposure >3 weeks after initial dose.

Warnings/Precautions:
Risk of thrombotic events: in patients with history of atherosclerosis, multiple cardiovascular risk factors, advanced age, impaired cardiac output, prolonged immobilization periods, and/or known/suspected hyperviscosity. Monitor baseline blood viscosity including those with cryoglobulins, fasting chylomicronemia/markedly high triglycerides, or monoclonal gammopathies. Severe thrombocytopenia. Coagulation disorders. Risk of transmission of blood-borne diseases. Elderly. Pregnancy (Cat.C). Nursing mothers.

Interaction(s)
May affect response to live virus vaccines; may defer until 3 months after Varizig administration.

Adverse Reaction(s)
Inj site pain, headache, chills, fatigue, rash, nausea; hypersensitivity reactions (discontinue if occurs).

How Supplied:
Kit—1 (vial + diluent)
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=ac96a331-e2ff-4839-a4d5-fda3d858c969