In a large study that evaluated the general safety of Zostavax (Zoster Vaccine Live), the Merck vaccine that helps prevent shingles (herpes zoster) in adults aged 60 or older, the safety profile of Zostavax was similar to that of placebo with respect to serious adverse events (SAEs), and the likelihood of experiencing a SAE was similar among those who received Zostavax and those who received placebo. These new data were presented at the 2010 American Geriatrics Society Annual Scientific Meeting in Orlando.

In this trial, there was no statistically significant difference in the estimated risk of SAEs between people who received Zostavax and those who received placebo, in both the 42-day and 182-day (six month) follow-up periods. Both study groups had similar overall safety profiles with respect to SAEs. This study did not assess the frequencies of AEs that were not serious. These trial results are similar to the overall vaccine safety findings seen in other clinical studies with Zostavax, including the pivotal phase-III Shingles Prevention Study (SPS).

“We are pleased to have these new data that add to the existing body of evidence that supports the safety profile of Zostavax,” said Paula Annunziato, senior director, Vaccines Clinical Research, Merck. “Zostavax provides an important public health benefit to help prevent shingles in older adults, and it is important that healthcare providers have information about the vaccine's benefits and safety to share with their patients.”

Zostavax is the only shingles vaccine licensed for use in the US, and is indicated for the prevention of herpes zoster (shingles) in people 60 years of age and older. Zostavax is not indicated for the treatment of zoster or postherpetic neuralgia (PHN). The US Centers for Disease Control and Prevention (CDC) recommends a single dose of Zostavax for all appropriate people 60 years of age and older regardless of whether they have had a prior case of shingles.

Customers will experience backorders, or periods where they are unable to place orders, for Zostavax throughout 2010 and possibly into 2011. Merck's goal is to have systems in place that will increase our manufacturing capacity and supply so that we can ensure a reliable supply of Zostavax in the future.

Zostavax is a live attenuated virus vaccine indicated for prevention of herpes zoster (shingles) in individuals 60 years of age and older. Zostavax is not indicated for the treatment of zoster or postherpetic neuralgia (PHN).

Vaccination with Zostavax may not result in protection of all vaccine recipients. Zostavax and Pneumovax23 (Pneumococcal Vaccine Polyvalent) should not be given concurrently because concomitant use resulted in reduced immunogenicity of Zostavax.

Zostavax is contraindicated in persons with a history of anaphylactic/anaphylactoid reaction to gelatin, neomycin, or any other component of the vaccine; with a history of primary or acquired immunodeficiency states including leukemia; lymphomas of any type, or other malignant neoplasms affecting the bone marrow or lymphatic system; or with AIDS or other clinical manifestations of infection with human immunodeficiency viruses. Zostavax is a live attenuated varicella-zoster vaccine and administration may result in disseminated disease in individuals who are immunosuppressed. Zostavax is also contraindicated in persons on immunosuppressive therapy. Zostavax is not indicated in women of childbearing age and should not be administered to pregnant females.

The duration of protection beyond four years after vaccination with Zostavax is unknown. The need for revaccination has not been defined. Vaccine efficacy for the prevention of herpes zoster was highest for subjects 60-69 years of age and declined with increasing age.

Transmission of vaccine virus may occur rarely between vaccinees and susceptible contacts. Zostavax is not indicated for prevention of primary varicella infection (chickenpox).

Shingles is marked by a blistering rash and is caused by the reactivation of the chickenpox virus. The risk for shingles increases as people get older, and the disease can occur at any time, without warning. According to the CDC, approximately one in three people will experience shingles in their lifetime. There are approximately one million cases of shingles in the United States each year, an estimated half of which occur in people 60 years and older.

The first signs of shingles are often felt and may not be seen, and may include itching, tingling, or burning. A few days later, a rash of fluid-filled blisters appears, usually on one side of the body or face. The blisters may take two to four weeks to heal. The rash can be painful, with the pain ranging from mild to severe. For most people, the pain from the shingles rash lessens as the rash heals, but for some people shingles can cause long-term nerve pain, called postherpetic neuralgia, or PHN, which can last for months or even years. This persistent nerve pain has been described as burning, stabbing, throbbing, or shooting pain. Other problems that may result from shingles include skin infection, muscle weakness, and scarring. A decrease or loss of vision or hearing can also occur if vision or auditory systems are affected.