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New Large Study Results Confirm Safety Profile of Zostavax, Merck's Shingles Vaccine, in People Aged 60 or Older

WHITEHOUSE STATION, N.J., May 13, 2010 – 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 today 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, M.D., 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 U.S., 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 U.S. 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.

In the study, safety profile for ZOSTAVAX similar to that of placebo
This randomized, double-blind, placebo-controlled, age-stratified study evaluated 11,980 people 60 years of age and older; 5,983 people received ZOSTAVAX and 5,997 received a placebo. Study participants were monitored for SAEs for 42 days after being vaccinated (primary follow-up period) and 182 days after being vaccinated (secondary follow-up period). The researchers calculated the relative risks for SAEs during the two follow-up periods for both groups. This study was conducted as part of post-marketing activities following the U.S. Food and Drug Administration's licensure of the vaccine in 2006.

In this study, within the primary follow-up period of 42 days, 84 people (1.4 percent) in the vaccine group and 67 people (1.1 percent) in the placebo group reported SAEs. During the secondary follow-up period of 182 days, 340 of participants (5.7 percent) in the vaccine group and 300 participants (5.0 percent) in the placebo group reported SAEs. Two people in the vaccine group reported SAEs (uveitis and sciatica) that the investigators deemed were related to the vaccine, while one person in the placebo group reported a SAE (lumbar radiculopathy) that the investigators deemed was related to the vaccine. There also were 24 fatal SAEs in the vaccine group and 17 in the placebo group during the study period; the deaths were not deemed by the investigators to be vaccine-related.

The estimated risk for SAEs in the primary follow-up period in the vaccine group was 1.41 percent (n=5983) and 1.12 percent in the placebo group (n=5997), with a relative risk of 1.26 (95 percent CI: 0.91, 1.73). The estimated risk of SAEs within the secondary follow-up period of 182 days was 5.68 percent in the vaccine group and 5.01 percent in the placebo group, with a relative risk of 1.13 (95 percent CI: 0.98, 1.32). The results at both 42 and 182 days indicate that there was no statistically significant difference in SAE risk between the vaccine group and the placebo group.

Important information about ZOSTAVAX
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 PNEUMOVAX®23 (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.

Vaccine-related, injection-site and systemic adverse experiences in ≥1% of individuals in the Adverse Event Monitoring Substudy (AEMS), a subgroup of individuals from the Shingles Prevention Study (SPS) who received ZOSTAVAX (n=3,345), included headache (1.4%) and the following injection-site reactions: erythema (33.7%), pain/tenderness (33.4%), swelling (24.9%), hematoma (1.4%), pruritus (6.6%), and warmth (1.5%). Most of these adverse experiences were reported as mild in intensity.

From Day 0 to 42 post vaccination, in the overall study population, serious adverse experiences (SAEs) occurred at a similar rate (1.4%) in subjects vaccinated with ZOSTAVAX or placebo. In the AEMS, the rate of SAEs was increased in the group who received ZOSTAVAX (1.9%) as compared to the placebo group (1.3%) from Day 0 to 42 post vaccination. Over the course of the entire study, in the overall study population, investigator-determined, vaccine- related serious adverse experiences were reported for 2 subjects vaccinated with ZOSTAVAX (asthma exacerbation and polymyalgia rheumatica) and 3 subjects who received placebo (Goodpasture’s syndrome, anaphylactic reaction, and polymyalgia rheumatica).

Among reported serious adverse events in the SPS (Days 0–42 post vaccination), serious cardiovascular events occurred more frequently in subjects who received ZOSTAVAX (20 [0.6%]) than in subjects who received placebo (12 [0.4%]) in the AEMS. The frequencies of serious cardiovascular events were similar in subjects who received ZOSTAVAX (81 [0.4%]) and in subjects who received placebo (72 [0.4%]) in the entire SPS study cohort (Days 0–42 post vaccination).

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 a painful disease that can be debilitating
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 1 in 3 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.

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Prescribing information and patient product information for ZOSTAVAX® are attached and are also available at

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Posted: May 2010