Developing new vaccines against pneumonia

Pneumonia is the leading cause of death in children less than five years old in the developing world. Each year, more than two million children die from pneumonia, mostly in low-resource countries. Streptococcus pneumoniae, or pneumococcus, the bacterium that is the most common cause of severe pneumonia, kills about one million of these children each year. Pneumococcus also causes sepsis (blood infection) and meningitis (brain infection), which kill and disable children worldwide, and is one of the leading causes of bacterial otitis media (middle ear infection). Vaccines are a critical strategy for protecting children from this deadly disease.

Pneumococcus has more than 90 serotypes, which vary by region. Current pneumococcal conjugate vaccines are effective against strains common in the industrialized world and some developing countries, but do not cover all pneumococcal serotypes. They are complex vaccines to manufacture and are expensive, which makes it difficult for poorer countries in most urgent need to be able to afford them without assistance. While the GAVI Alliance has responded by funding the introduction of current pneumococcal vaccines in low-income countries, new vaccines are needed that are intrinsically more affordable and that can provide either focused protection for children against strains prevalent in the developing world or broad protection across all pneumococcal strains.

Working to provide widespread protection

PATH is pursuing a number of approaches to develop pneumococcal vaccines that will be effective and affordable in the countries that most urgently need them. The pneumococcal vaccine project at PATH is partnering with scientists and manufacturers to advance their research toward preventing this childhood disease. We are working from initial discovery through clinical trials to shorten the timeline for developing vaccines to serve the countries in greatest need.

One approach that PATH believes holds particular promise is the development of “common protein” vaccines. Vaccines containing proteins that are common to all pneumococcus serotypes could provide broad protection to children worldwide. PATH has also partnered to develop an inactivated whole-cell vaccine against pneumococcus that could provide affordable and broad protection for children. Finally, PATH is exploring the potential of new conjugate technologies that would more efficiently attach the antigen—the agent prompting an immune response—to “carrier proteins” in order to target coverage of strains that are most prevalent in developing countries and to reduce the cost compared with the currently available vaccines.

PATH also supports activities to benefit the pneumococcal research community. Research activities include cataloging pneumococcal strain collections, assessing what kind of preclinical testing should be used to evaluate vaccines, and identifying production processes so that vaccines are affordable for distribution by public health systems in low-income countries.

PATH collaborates with partners such as vaccine manufacturers and academic and research institutions and coordinates with other global health bodies such as the World Health Organization, the GAVI Alliance, the Pneumoccocal Awareness Council of Experts (PACE), and the US Centers for Disease Control and Prevention. Through public-private partnerships, PATH is accelerating development of safe, effective, and affordable pneumococcal vaccines to protect children worldwide.