Off Beat

Tinkering, not marking the great leap

 
Last Updated: Sunday 28 June 2015

Off Beat

Research on some diseases is taking off in a big way. These diseases have been out of the ambit of routine immunisation programmes, because they have traditionally been concentrated in developing countries. Now that they are increasingly being transmitted to the developed world because of increased and easier contact, research is concentrating on them. But new research is tinkering with existing vaccines rather than focussing on radical, cutting-edge solutions. One significant feature of the research scenario is that the majority of the funding is coming from the Bill and Melinda Gates Foundation.

HIV/AIDS Down to Earth More than 40 preventive vaccines for HIV/AIDS are being tested around the world. Aventis, Merck, Chiron and GlaxoSmithKline GSK are some of the companies in the forefront of research. But two phase-III trials carried out in Thailand and the US have not demonstrated any significant level of efficacy. Though VaxGen's AIDSVAX was shown to be ineffective in North America, Europe and Thailand, it was combined with another failed vaccine, Aventis Pasteur's ALVAC-HIV, and further trials were carried out in Thailand in 2004. International AIDS Vaccine Initiative (IAVI) estimates total annual spending on AIDS vaccine research at US $682 million.

Current levels of funding, though massive, still fall almost halfway short of the us $1.2 billion that is estimated to be necessary to develop an effective vaccine. The Gates foundation, which is heavily involved in funding the development of a hiv/aids vaccine through the Global hiv Vaccine Enterprise, has set up has made numerous contributions to research on a hiv/aids vaccine. One of the most significant was a us $100 million grant to iavi in 2001.

Rotavirus Down to Earth Rotavirus kills about 500,000 children annually. Around 80 per cent of cases occur in the developing world, though the disease, a severe form of diarrhoea, is fairly common even in developed countries. In the us, 50,000 children are hospitalised each year for rotavirus. To protect them, the us Food and Drug Administration (fda) had licensed RotaShield, a rhesus-based recombinant vaccine, in August 1998. The drug was, however, removed from the market when post-marketing surveillance showed there were increasing reports that it caused fatal intestinal damage, after about 1.8 million doses of vaccine had already been sold.

New vaccines are being developed through the Rotavirus Vaccine Program (rvp), initiated in 2003 by path, an ngo that is a gavi member. rvp received an initial us $30 million from the Vaccine Fund. It will use this money to promote new vaccines that are being developed. At present there are a total of eight candidates in various stages of development. Rotarix will be marketed by gsk, and is likely to be ready for routine immunisation in Asia and Africa by 2009. Though not against Rotarix, who had informal consultation in February 2005 on quality, safety and efficacy specifications for rotavirus vaccines. Experts then agreed safety data on the vaccine was insufficient.

There are suggestions that trials are being carried out in developing countries to test safety standards before the new drugs are marketed in the us.

Meningitis project Down to Earth Meningitis a causes major epidemics in sub-Saharan Africa, with a fatality rate of about 10 per cent. In 2001, the Gates foundation gave who and path us $70 million over 10 years for the Meningitis Vaccine Project (mvp), to eliminate the disease, an infection of the fluid around the brain and spinal cord caused by the bacterial group called meningococci.

Worldwide, 250 million people are at risk of contracting the disease. In sub-Saharan Africa, a vaccine developed in the West is used as an emergency measure, but it doesn't protect young children. It also gives immunity for only three to five years. A new vaccine is being developed through a collaboration of three groups: the SynCo Bio Partners B V in Amsterdam, sii and the Centre for Biologics Evaluation and Research of the us Food and Drugs Administration (fda), which is providing the technology. fda has transferred the technology to sii, which will manufacture the vaccine . At a target price of us $0.40 per dose, it will cost us $100 million to cover a population of 250 million people over 10 years. This translates into raising about us $10-12 million annually.

Malaria Down to Earth Developing a malaria vaccine is difficult because the malaria parasite goes through several stages, even while inside the human host. Protection at each stage requires a different response, which a single vaccine might not be able to provide. As of now, there are 10 vaccine development projects. Two of these are conducting clinical trials in Africa. Nine projects target P falciparum , the most deadly form of malaria, while one focusses on P. vivax , the most widespread form. But a report by Malaria R&D Alliance, an international coalition of malaria research groups, found that annual spending on malaria research totalled us $323 million in 2004 -- less than 0.3 per cent of total health research spending worldwide. Just a part of this is for vaccines. The Malaria Vaccine Initiative (mvi), established under path in 1999 with a us $50 million grant from the Gates foundation which gave an additional us $100 million in 2003, coordinates malaria research. In November 2005, the foundation pledged another us $107.6 million payable over five years. A vaccine developed by gsk Biologicals and mvi has protected a significant percentage of children for at least six months in tests in southern Mozambique.

Human papillomavirus Down to Earth Human papillomavirus (hpv) is a sexually transmitted disease and is the major cause of cervical cancer in women, which accounts for the largest number of carcinogenic deaths among women in developing countries. The developing world accounts for 80 per cent of hpv deaths. Phase- iii trials for two new commercial vaccines against this disease are underway.

Trials for one, developed by Merck, are being carried out on 20,000 women. The results are awaited. The other vaccine is being tested by gsk -- trials began in 2004. The vaccines are against type 16 and 18 hpv, which account for 70 per cent of cervical cancer cases. The duration of immunity is not known. The new vaccines would have to be given to adolescent girls, unlike traditional vaccines which are given to infants and pregnant women. who received a us $7-million grant from the Gates foundation in June 2005 to promote the development of these vaccines.

Pneumonia Down to Earth The bacterium Streptococcus pneumoniae is the most common cause of severe pneumonia and meningitis, worldwide. It is estimated that the bacterium kills 1.6 million people, mostly women and children, annually. In developing countries, one in every 10 deaths of young children is attributed to this infection. Although vaccines for adults and children aged two and over are available, these don't work for infants below two, who are the most vulnerable group. The existing vaccines are effective against some strains of the bacterium, but not against the 12-25 per cent of cases in developing countries.

gavi is now funding a project to develop a variant of the existing vaccine for children below the age of two, to the tune of us $30 million. The research project, a public-private partnership, is being conducted by a team called Pneumo adip, which is based in the Bloomberg School of Public Health at Johns Hopkins University, usa. The vaccine industry, which is involved in the project, has already developed some new vaccines that are effective against some of the strains m ost common in developing countries. These vaccines are now being evaluated in large-scale field trials in Africa, Asia and Latin America.

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