News from the Second Regional Pneumococcal Symposium São Paulo, Brazil
Pneumococcal Vaccines in Development Pipeline May Offer More Options to Save Lives and Prevent Disease in Latin America
At Major Scientific Meeting in S. Paulo, Scientists with Public and Private Laboratories Report Dramatic Progress on New Vaccines, as Reports of Vaccine Impact in USA Exceed Expectations
São Paulo, Brazil, 14 December 2006 (PAHO)—Some 325 public health experts, leading policy makers and vaccine industry representatives today heard new evidence of the effectiveness of a pneumococcal vaccine used in the United States. Vaccine manufacturers also revealed the status of several new vaccines in the pipeline, including some being developed by manufacturers in middle- and low-income countries.
Across Latin America, pneumococcal disease claims 18,000 lives every year and causes 1.6 million cases of childhood disease. An effective vaccine is used against the disease in the United States and a number of other developed countries, but is not yet used in Latin America or developing countries, in part because of its high cost.
Now, new evidence presented yesterday showed an even greater vaccine impact than had been anticipated. In the United States, where the pneumococcal vaccine has been used since 2000, invasive pneumococcal disease has been reduced by 80% in children under five. Even more surprising, epidemiologists have found that this disease reduction in vaccinated children has had a large spillover effect, reducing vaccine-type disease in older adults by about 82% according to Dr. Cynthia Whitney of the United States Centers for Disease Control and Prevention. This "herd immunity" has reduced invasive pneumonia by half in babies under two—who are too young to be vaccinated.
In Latin America, widespread use of the existing vaccine would save the life of one child every hour and cut the incidence of pneumococcal disease by almost half, not only easing the suffering of children but also reducing the considerable economic and social costs of disease.
The vaccine, produced by Wyeth Pharmaceuticals, is a "conjugate" vaccine that joins seven strains of the pneumococcus bacteria to a protein produced by diptheria. The vaccine protects children against these seven strains. But while the seven strains are those most common in the United States, the vaccine does not contain several other strains that cause additional disease in Latin America.
Potential new vaccines in the pipeline could get around this problem in a number of creative ways, and some may ultimately prove less costly as well. Presenters at the symposium described a number of these new vaccines under development.
New Vaccines in the Pipeline
New vaccines primarily include conjugate vaccines that contain up to 13 strains of the bacteria as well as more experimental protein vaccines. The latter use pneumococcal proteins involved in the disease process, which are shared across many, if not all, of the 23 disease-causing strains of pneumococcus.
Akira Homma, director of the Brazilian governmental vaccine producer Bio-Manguinhos, described the work of the Developing Country´s Vaccine Manufacturers Network (DCVMN), whose goal is to provide quality vaccines at affordable prices to the developing world.
Homma estimated the size of the potential global market for pneumococcal vaccines to be 305 million doses a year: 40 million doses in high income countries; 130 million in middle income; and 135 million in low income, and noted that the vaccine industry does not currently have the capacity to produce at this volume. He estimated "an enormous deficit of 250 million doses."
Emerging manufacturers have at least several conjugated vaccines in preclincal development. Homma noted the challenges facing emerging manufactures that wish to invest in innovation, adding that "To bring prices down, new manufacturers need to enter the market."
Luciana Cerqueira Leite of the Biotechnology Center of the Butantan Institute in Brazil reviewed their current efforts to develop pneumococcal vaccines. These include a collaborative effort with Children's Hospital, Harvard to develop a whole cell pneumococcal vaccine administered intranasally; a vaccine that conjugates polysaccharide and a pneumoccal protein known as PspA; and potential DNA vaccines, as well as others.
Multinational Pharmaceutical Companies
Multinational pharmaceutical companies have about 20 vaccines in various stages of development, from preclinical development to phase 3 trials.
William Hausdorf with GSK Biologicals discussed a novel vaccine approach that conjugates 10 strains of pneumococcus with a protein from Haemophilus influenzae (Hi) resulting in substantial protection against both pneumococcal and Hi disease. GSK will soon be conducting two Phase III trials of the vaccine, one in Panama and the other in Argentina.
Robert Hopfer said that Sanofi-Pasteur is pursuing both a conjugate vaccine, now in preclinical development, and a protein vaccine which is within weeks of entering a Phase 1 clinical trial.
Peter Paradiso reported that Wyeth's 13-strain vaccine—which includes several strains prevalent in Latin America in addition to the original seven—has completed Phase 2 trials. In those trials, the additional six added strains did complemented the original seven, providing a strong proof of concept. Wyeth is therefore preparing to enter Phase 3 clinical trials, and anticipates that the new vaccine could be available in two years.
"All these developments are very promising. We understand it is clearly better to prevent than to treat pneumococcal disease," said Expedito Luna, with the Brazil's Ministry of Health.
"At the same time, these decisions must depend on national, scientific and technological developments. We must involve national producers to gaurantee sustainability and a reduction of prices."