The U.S. Centers for Disease Control and Prevention's (CDC) Advisory Committee on Immunization Practices (ACIP) voted unanimously yesterday to recommend that adults ages 19 to 64 with asthma receive pneumococcal polysaccharide vaccine (PPSV23), known as PNEUMOVAX® 23 (Pneumococcal Vaccine Polyvalent). Merck & Co., Inc. is the sole supplier of PNEUMOVAX 23 in the United States. The ACIP based this recommendation on study data that showed an increased risk of pneumococcal disease among people with asthma. Pneumococcal diseases are caused by common bacteria and can lead to potentially serious bacterial infections of the lungs (pneumonia), lining of the brain (meningitis) and blood (bacteremia).

The ACIP also voted to recommend that people aged 19 through 64 years who smoke cigarettes should receive PPSV23 as well as smoking-cessation counseling. This recommendation is the first time the ACIP has recommended a vaccine specifically for people who smoke. The ACIP stated that people at increased risk for invasive pneumococcal disease include those who smoke cigarettes. This recommendation is based on data that showed smokers are approximately four times more at risk for pneumococcal disease than non-smokers. Data also showed that smoking was significantly associated with invasive pneumococcal disease, which includes potentially serious infections, such as meningitis or bacteremia. The current physician prescribing information for PNEUMOVAX 23 does not include data on the use of the vaccine in people who smoke cigarettes, nor does it include cigarette smokers among those who should be vaccinated. However, the ACIP has noted that many people who smoke cigarettes may have another condition for which PNEUMOVAX 23 is currently recommended. ACIP has previously recommended the use of PPSV23 in all adults 65 years of age and older, and for certain individuals ages 2 years and older at increased risk for developing pneumococcal infection or experiencing severe disease and complications because of chronic illness or underlying medical conditions.

PNEUMOVAX 23 is indicated for vaccination against pneumococcal disease caused by those pneumococcal types included in the vaccine. PNEUMOVAX 23 is contraindicated in individuals who are hypersensitive to any component of the vaccine. PNEUMOVAX 23 will not prevent disease caused by capsular types of pneumococcus other than those contained in the vaccine.

The ACIP also voted to revise the recommendations for use of PPSV23 in Alaskan Native and American Indian children and adults and to clarify the recommendations for revaccination of high-risk children. For these children, the ACIP voted to recommend that routine use of PPSV23 after administration of PCV7 (pneumococcal conjugate vaccine) is not recommended for Alaskan Native or American Indian children aged 24 through 59 months. However, in special situations, public-health authorities may consider recommending PPSV23 after PCV7 for Alaskan Native or American Indian children aged 24 through 59 months who are living in areas in which risk of invasive pneumococcal disease is increased. For adults, ACIP stated that routine use of PPSV23 is not recommended for Alaskan Native or American Indian people younger than 65 years old unless they have underlying medical conditions that are PPSV23 indications. However, public health authorities may consider recommending PPSV23 for Alaskan Natives and American Indians aged 50 through 64 years who are living in areas in which the risk of invasive pneumococcal disease is increased.

Regarding revaccination of high-risk children, the ACIP stated that a second dose of PPSV23 is recommended five years after the first dose of PPSV23 for people ages 2 and older who are immunocompromised, have sickle-cell disease, or functional or anatomic asplenia.

Details of these ACIP provisional recommendations for pneumococcal vaccination will be made available from the CDC. These provisional recommendations are under review by the director of the CDC and the Department of Health and Human Services and will become official when published in CDC's Morbidity and Mortality Weekly Report (MMWR).

About PNEUMOVAX 23

PNEUMOVAX 23 is the only pneumococcal vaccine approved in the U.S. for use in adults. According to the prescribing information for PNEUMOVAX 23, the vaccine is recommended for routine vaccination of people 50 years of age or older, and select other individuals ages 2 years and older with certain risk factors. Specifically, PNEUMOVAX 23 is recommended for immuno-competent individuals ages 2 years and older with chronic cardiovascular disease (including congestive heart failure and cardiomyopathies), chronic pulmonary disease (including chronic obstructive pulmonary disease and emphysema), diabetes mellitus, those with alcoholism, chronic liver disease (including cirrhosis) or cerebrospinal fluid leaks, and with functional or anatomic asplenia (including sickle cell disease and splenectomy).

PNEUMOVAX 23 is also recommended per the prescribing information for people ages 2 years and older who live in special environments or social settings (including Alaskan Natives and American Indian populations). Certain immunocompromised people ages 2 and older are also recommended for PNEUMOVAX 23 -- those with HIV infection, leukemia, lymphoma, Hodgkin's disease, multiple myeloma, generalized malignancy, chronic renal failure or nephrotic syndrome; those receiving immunosuppressive chemotherapy (including corticosteroids); and those who have received an organ or bone marrow transplant. Vaccination with PNEUMOVAX 23 may not offer 100 percent protection from pneumococcal infection. PNEUMOVAX 23 is administered as a single dose subcutaneously or intramuscularly (preferably in the deltoid muscle or lateral mid-thigh).

The ACIP states that PNEUMOVAX 23 may be administered at the same time as the influenza vaccine (by separate injection in the other arm) without an increase in side effects or decreased antibody response to either vaccine. In contrast to influenza vaccine, pneumococcal vaccine is not recommended annually.

Selected Important Information about PNEUMOVAX 23

The most common adverse experiences reported with PNEUMOVAX 23 in clinical trials were: local reaction at injection site including soreness, erythema, warmth, swelling and induration, and fever (<=)102 degrees Fahrenheit.

In post-marketing experience, injection site cellulitis-like reactions were reported rarely; between 1989 and 2002, when approximately 43 million doses were distributed, the annual reporting rate was <2/100,000 doses. These cellulitis-like reactions occurred with initial and repeat vaccination at a median onset time of two days after vaccine administration.

Revaccination of immunocompetent persons previously vaccinated with 23-valent polysaccharide vaccine is not routinely recommended. Revaccination once is recommended for persons ≥2 years of age who are at highest risk of serious pneumococcal infection and those likely to have a rapid decline in pneumococcal antibody levels, provided that at least five years have passed since receipt of a first dose of pneumococcal vaccine. If prior vaccination status is unknown for patients in the high-risk group, patients should be given pneumococcal vaccine. The highest risk group includes persons with functional or anatomic asplenia (eg, sickle cell disease or splenectomy), HIV infection, leukemia, lymphoma, Hodgkin's disease, multiple myeloma, generalized malignancy, chronic renal failure, nephrotic syndrome, or other conditions associated with immunosuppression (eg, organ or bone marrow transplantation), and those receiving immunosuppressive chemotherapy (including long-term systemic corticosteroids).

Because data are insufficient concerning the safety of pneumococcal vaccine when administered three or more times, revaccination following a second dose is not routinely recommended.

In a clinical trial, an increased rate of local reactions has been observed with revaccination at 3 to 5 years following primary vaccination. For subjects aged (>=)65 years, it was reported that the overall injection-site adverse experiences rate was higher following revaccination (79.3 percent) than following primary vaccination (52.9 percent). For subjects aged 50 to 64 years, the reported overall injection-site adverse experiences rate for re-vaccinees and primary vaccinees were similar (79.6 percent and 72.8 percent, respectively).

In both age groups, revaccinees reported a higher rate of a composite endpoint (any of the following: moderate pain, severe pain, and/or large induration at the injection site) than primary vaccinees (age ≥65 years: 30.6 percent vs. 10.4 percent; age 50 to 64 years: 35.5 percent vs. 18.9 percent). The rate of vaccine-related systemic adverse experiences was higher following revaccination than primary vaccination in subjects ≥65 years of age (33.1 percent vs. 21.7 percent), and was similar following revaccination and primary vaccination in subjects 50 to 64 years of age (37.5 percent vs. 35.5 percent).

About the Advisory Committee on Immunization Practices (ACIP)

The ACIP develops written recommendations for the routine administration of vaccines, along with schedules regarding the appropriate dosage and dosing frequency, and contraindications applicable to the vaccines. The goals of the committee, which consists of 15 experts in immunization and related fields, are to provide advice which will assist the CDC and the nation in reducing the incidence of vaccine-preventable diseases and to increase the safe usage of vaccines and related biological products.

About Merck

Merck & Co., Inc. is a global research-driven pharmaceutical company dedicated to putting patients first. Established in 1891, Merck currently discovers, develops, manufactures and markets vaccines and medicines to address unmet medical needs. The Company devotes extensive efforts to increase access to medicines through far-reaching programs that not only donate Merck medicines but help deliver them to the people who need them. Merck also publishes unbiased health information as a not-for-profit service.

Forward-Looking Statement

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PNEUMOVAX 23® is a registered trademark of Merck & Co., Inc., Whitehouse Station, N.J., U.S.A.

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