Tuesday, May 05, 2009
[Caption] The WHO has convened a meeting of all flu vaccine manufacturers to discuss production of a pandemic vaccine against the H1N1 strain.
Two years ago, the Serum Institute of India based in Pune, the country’s largest vaccine manufacturer, joined an initiative launched by the World Health Organisation (WHO) to encourage six companies in developing countries to make influenza vaccines. At that time, the WHO was worried that the deadly H5N1 strain of bird flu might suddenly turn highly infectious in humans and send the virus rampaging across the globe.
Then, large quantities of a vaccine against such a pandemic flu strain would be needed as quickly as possible. Much of the world’s flu vaccine production capacity is currently concentrated in the industrialised nations. Besides, the richer countries are able to negotiate bulk contracts in advance with large manufacturers for pandemic vaccines.
But, now a flu strain known as Influenza A(H1N1) that originated in pigs is threatening a full-scale pandemic.
The Director-General of the WHO has already convened a meeting of all flu vaccine manufacturers, including those in developing countries, to discuss production of a pandemic vaccine against the H1N1 strain, said Marie-Paule Kieny, Director of WHO’s Initiative for Vaccine Research, at a press briefing recently.
The relative mildness of disease caused by the H1N1 strain outside of Mexico did not mean that a potential pandemic would remain mild. Preparations to make a pandemic vaccine against the H1N1 strain should proceed, she emphasised. “This is too much of a gamble over public health to say, ‘Well, let’s see if it really becomes severe.’”
High global demand
Producing a pandemic vaccine is “a long journey,” remarked Dr. Kieny. From the time a potentially pandemic flu strain is identified, it takes between four and six months to have the first doses of the vaccine coming out of the factory. The best estimates currently available indicated that there would be a minimum of one to two billion doses of the vaccine available in one year, she added.
A recent study carried out by Oliver Wyman, an international strategy consulting firm, in collaboration with the WHO and the International Federation of Pharmaceutical Manufacturers & Associations (IFPMA), found that the capacity to make a pandemic flu vaccine had increased 300 per cent over the last two years. This would not be sufficient to meet global need for emergency production of a pandemic vaccine, said an IFPMA press release issued in February this year.
The IFPMA press release noted that the most likely case was of the manufacturers producing 2.5 billion doses of a pandemic vaccine in a year. At that rate, it would take four years to satisfy the global demand. But in the best case, if 7.7 billion doses could be produced in the first 12 months, global demand would be satisfied in one and a half years.
The WHO will approach the Serum Institute of India as also the other five vaccine manufacturers in developing countries to see if they could produce a pandemic vaccine against the current H1N1 strain, said Dr. Kieny. According to her, these six companies had received funding and technical assistance from the WHO to produce flu vaccines.
The six companies chosen by the WHO had first to demonstrate their ability to produce a seasonal flu vaccine, said Suresh Jadhav, executive director of the Serum Institute of India. If a company could not produce the seasonal flu vaccine, it would not have the infrastructure and the expertise to make pandemic vaccines. “It is like a proof-of-concept to show them that you can handle the seasonal [vaccine], therefore you will be in a position to handle the pandemic strain,” he told this correspondent. -snip-
The Serum Institute of India showed that it could produce the seasonal flu vaccine and was subsequently given the H5N1 bird flu seed virus to produce a pandemic vaccine. The H5N1 pandemic vaccine made by the company was now undergoing animal studies, according to Dr. Jadhav.
Now that the H1N1 strain, which might potentially produce a pandemic, had been isolated, the Centers for Disease Control in the U.S. as well as other WHO Collaborating Centres were "tweaking" the virus in order to create a seed strain that would then be shipped to vaccine manufacturers, said Dr. Kieny. This would be completed by mid- to end-May, she said.
The Serum Institute of India can then innoculate the seed strain of the H1N1 virus into fertilised hen’s eggs or animal cells that can be grown in culture. Although use of eggs is the time-honoured method for making flu vaccines and is still the dominant technique in terms of production volumes, cell culture processes are catching on. -snip-
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