Pneumococcal vaccine development resumed again in 1968, this time at the insistence of National Institutes of Health (NIH) scientist Dr. Robert Austrian. Austrian had witnessed numerous antibiotic treatment failures in the clinical setting and believed pneumococcal disease rates to be much higher than reported due to a significant decrease in the use of testing to confirm a diagnosis.
Eli Lilly & Co was granted a contract by the NIH to research and develop an effective pneumococcal polysaccharide vaccine. In 1972, vaccine trials of Eli Lilly’s pneumococcal vaccine began in South Africa; however, by 1975, Eli Lilly had terminated its research and development after several issues with the vaccine occurred.
Meanwhile, Merck, Sharp, and Dohme, with knowledge and experience related to the research and development of a meningococcal polysaccharide vaccine for the United States Army in the late 1960s, had already started on a pneumococcal polysaccharide vaccine development by 1970. Merck also chose to complete pneumococcal vaccine clinical trials in South Africa and reported that their 6 and 12-valent vaccines reduced pneumococcal pneumonia disease rates by 76 and 92 percent respectively.
Merck applied for a license to manufacture and market a 14-valent pneumococcal capsular polysaccharide vaccine, PNEUMOVAX, in 1976 and received FDA approval for the vaccine on November 21, 1977. In January 1978, the CDC’s Advisory Committee on Immunization Practices (ACIP) recommended that the new pneumococcal vaccine be administered to all children and adults aged two and older with chronic health conditions which included sickle cell anemia, splenic dysfunction, diabetes mellitus, and chronic renal, lung, liver, and kidney disease. The vaccine was also approved for use during a pneumococcal outbreak involving a closed population, such as a nursing home or similar institution.
Lederle, another established vaccine manufacturer, had also begun research and development for a pneumococcal polysaccharide vaccine in the 1970s and in August 1979, PNU-IMUNE, its 14-valent pneumococcal vaccine, received FDA approval.
By the early 1980s, pneumococcal experts recognized the need to expand the number of pneumococcal strains contained within the polysaccharide vaccine to improve coverage on a global scale. The World Health Organization (WHO) along with the governments of several countries, reported that a 23-valent pneumococcal vaccine would provide better protection against pneumococcal disease worldwide.
In 1983, both Merck and Lederle introduced pneumococcal polysaccharide vaccines (PPV23) containing 23 strains of pneumococcal which were believed to cause approximately 87 percent of all bacterial pneumonia cases in the United States. The PPV23 vaccines were reformulated to contain 25mcg of each specific antigen, a decrease from the 50mcg per antigen found in the 14-valent vaccine, in an attempt to better balance safety and immune response.
The CDC’s Advisory Committee on Immunization Practices (ACIP) voted in 1984 to recommend that all adults 65 and older receive a dose of PPV23 vaccine. This recommendation was made despite two separate studies showing that the vaccine was ineffective at reducing pneumococcal infections and deaths. The CDC also continued to recommend that all adults and children aged two and older with chronic illness or immunosuppression receive a dose of the vaccine.
In 1997, PPV23 recommendations were updated to include special populations such as individuals living in nursing homes and other long-term care facilities and for use in Alaskan Natives and certain American Indian populations.
