Jill Wechsler
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The need to strengthen public health at home and abroad is expanding the development of new medicines and vaccines to prevent
and treat infectious diseases around the world. Donor nations and organizations have increased funding over the last decade
to bolster healthcare systems in less developed countries and to improve treatments for malaria, tuberculosis, and many neglected
tropical diseases. Biopharmaceutical companies have joined public-private partnerships (PPPs) developing these therapies,
attracted by the desire to expand sales globally as well as opportunities to improve third-world health. Many PPPs are poised
to harvest rewards from over a decade of research efforts, but require billions in additional resources to finance costly
research and clinical trials.
INVIGORATING VACCINES
A main thrust of these initiatives is to spur research and development (R&D) on new vaccines to prevent infections that kill
millions of people every year. The PATH Malaria Vaccine Initiative is launching Phase 3 trials for a promising malaria vaccine
developed by GlaxoSmithKline (GSK), and the Aeras Global TB Vaccine Foundation has several candidates in early clinical trials.
Rotavirus vaccines recently received a strong push from the World Health Organization's decision to add this preventive to
national immunization programs for infants and children.
Vaccine development is strong at home as well, as new preventives for human papillomavirus, rotavirus, and shingles have hit
the market. The US Food and Drug Administration approved three vaccines last year, and several important applications are
in the queue. Meanwhile, the agency has its hands full reviewing filings for the new pandemic H1N1 vaccine, now being tested
and produced as fast as possible. The US expects to spend some $8 billion for nearly 200 million doses of the flu vaccine
from GSK, Novartis, Sanofi Pasteur, Astra-Zeneca's MedImmune, and Australia-based CSL Limited. European and other nations
have placed comparable orders.
The FDA and the industry face several challenges in meeting the demand for H1N1 vaccines, as discussed at a July meeting of
FDA's Vaccines and Related Biological Products Advisory Committee. The agency is allowing licensed manufacturers to file manufacturing
supplements for a strain change, similar to what companies do each year for new seasonal flu vaccines. Because the H1N1 vaccine
is a slightly different single-strain vaccine, companies have to conduct clinical trials to ensure safety, determine the necessary
dose strength for effectiveness, and decide whether one or two doses are needed. Another question is whether the swine flu
vaccine should be administered separately or with a seasonal flu shot.
The National Institutes of Health is conducting additional clinical trials to test dosing options for various age groups and
the need to mix the new vaccine with an adjuvant to achieve the desired immune response. If an adjuvant is needed, the FDA
plans to use its emergency authority to expedite access to what would then be a new vaccine. The agency took this route earlier
in the year to permit treatment of infants with antivirals not yet labeled for that age group, but has not used this approach
for a new vaccine.
Even if all the testing comes out well, it's not clear how quickly the industry will produce the millions of needed doses.
Companies experienced difficulties cultivating antigen from the available H1N1 strains, but yields began to rise last month,
generating hopes for initial supplies in September. MedImmune reported great success in producing bulk quantities of its FluMist
vaccine, which is made from a live virus, but doesn't have enough nasal spray devices to deliver the inhaled product.
BROADER IMPACT
MedImmune's excess supply, though, may lead to overseas sales, as vaccine makers capitalize on the opportunity created by
the flu pandemic to expand production and distribution. Sanofi gained FDA approval for its new Swiftwater, PA, vaccine manufacturing
facility earlier this year, while foreign manufacturers, such as Sinovac Biotech in China, have geared up to conduct clinical
trials and expand production of a influenza vaccine at home. Struggling Connecticut-based Protein Sciences Corporation has
received federal funding to develop new flu vaccine development methods, leading to testing for its experimental PanBlok vaccine.
Inovio Biomedical of San Diego has gained attention from positive animal studies on its DNA-based flu vaccine, although it
will take several years to bring such a product to market.
The demand for a pandemic flu vaccine also has spurred development of novel antigens and testing standards. Earlier this year,
FDA scientists unveiled a new antigenic fingerprinting approach for testing the potential protective activity of vaccines
under development. Vaccine makers are moving forward with the development of a cell-based manufacturing technology for influenza
vaccine, the long-desired approach for accelerating seasonal flu vaccine production.
