Chicken Pox Injection Approved to Decrease Severity in High Risk Patients
Chicken Pox Injection Approved to Decrease Severity in High Risk Patients
The Cangene Corporation’s varicella immune globulin preparation Varizig has received FDA approval in recent weeks and will be used to reduce the severity of chickenpox infections in high-risk individuals when given within 4 days of exposure. While the drug has been in use for some time in Canada, where the Cangene Corporation is headquartered, it has only been available through a limited investigational expanded-access protocol during the licensing process in the United States until now.
While many people in the United States have immunity to the virus responsible for chickenpox in children (as well as shingles in older patients), known as varicella-zoster virus (VZV), as a result of immunization or exposure to the virus in childhood, some few individuals without immunity may experience severe infections that can be fatal. Varizig is the only FDA-approved immune globulin currently on the market for VZV after exposure and fills an unmet need by providing treatment for potentially fatal infections in vulnerable patients.
The persons at greatest risk for these infections are children and adults with weakened immune systems, pregnant women, and infants exposed during pregnancy or after birth. Occasionally, healthy people without VZV immunity may also contract severe infections and, as with all antiviral treatments, Varizig may not always be effective or cannot be used in some cases.
Varizig is an antibody preparation manufactured from the plasma of healthy donors with high anti-VZV antibody levels. Varizig is administered in 2 or more injections, depending on the weight of the recipient, within 96 hours of exposure. It is currently approved for immunocompromised children and adults, newborns, pregnant women, premature infants, children younger than 1 year, and adults with no immunity to VZV.
Varicella-zoster immune globulin (VZIG) has been shown to lower the risk of severe infections if given soon enough after exposure. An earlier FDA-licensed VZIG was removed from the US market by the manufacturer in 2006.
Since pharmacists often act as front line health care professionals, you may have customers who come in looking for ways to treat chicken pox symptoms but don’t know they have chicken pox. If you can identify that any of these people belong to a high risk population, it would be worthwhile to encourage them to make an appointment with their physicians to hopefully limit the severity of their infection. If your pharmacy has its own clinic, it would be beneficial to offer Varizig to appropriate patients.