HHS takes steps to bolster supply of flu vaccine

Dr. Bruce Gellin, director of the National Vaccine Program Office at the Health and Human Services Department, talked to National Journal about the nation's vaccine supply. Following are edited excerpts.

NJ: Could we make enough vaccine right now to combat an avian-flu pandemic?

Gellin: We have a long way to go. Global influenza vaccine manufacturing capacity is limited, and we currently have only a single manufacturer -- Sanofi -- that produces all components of influenza vaccine entirely within our borders. In a pandemic, vaccine will be in short supply everywhere, and we can't assume that vaccine produced elsewhere will be delivered here. There are other vaccine production facilities within the U.S., but influenza vaccine manufacturing uses dedicated facilities.

Because a pandemic will be caused by a virus that we've not experienced before, a pandemic vaccine is likely to be a much higher dose to achieve the immune response needed for protection. In studies that [the National Institutes of Health] conducted last year, we were sobered to learn that the vaccine dose was six times higher than what is in our seasonal flu shot and that two doses were required.

NJ: Right now, how many doses of a pandemic vaccine could be produced entirely within the United States?

Gellin: We estimate that if we were to ask Sanofi to dedicate their facilities entirely to H5N1 vaccine, they could produce approximately 30 million to 40 million doses of H5N1 vaccine in a year. At two doses per person, we could vaccinate only 15 million to 20 million Americans in a year. Of course, this would also mean that the company would have to stop making next year's flu vaccine in order to do this.

NJ: How is HHS helping to improve our vaccine preparedness for a pandemic?

Gellin: First, all licensed influenza vaccines are made in specialized live eggs -- not what's in the grocery store. Therefore, we've worked with manufacturers and egg suppliers to shore up the egg supply so that hundreds of thousands of eggs are available to produce a pandemic vaccine at any time.

Second, we are encouraging all people who are currently recommended to receive an annual flu shot to make this a habit. The [Centers for Disease Control and Prevention] recommends that over 185 million people receive a flu shot each year, but as a country we've never been able to achieve half of that. Increased annual demand will translate into increased capacity to provide this increased supply.

Third, we are working with companies to diversify the manufacturing of influenza vaccine so that we are not totally dependent on eggs. There are other ways to grow viruses in massive quantities. One that has received lots of attention is cell-based technology. This system is used for the manufacture of other vaccines -- for example, polio.

Fourth, we are encouraging companies and the scientific community to explore approaches that will allow the dose of a pandemic vaccine to be lower than what we found in the initial studies of the H5N1 vaccine. There is emerging evidence that this could work by adding an adjuvant or giving the vaccine into the skin rather than the muscle to enhance the vaccine's immune response.

Fifth, we are searching for a truly next-generation flu vaccine -- one that protects more broadly against a wide range of flu viruses so that we will no longer have to make a flu vaccine that is tailored specially to the viruses that are the threat of the day.

NJ: Why haven't companies switched to modern approaches?

Gellin: Unlike other parts of the pharmaceutical market, influenza vaccine manufacturing isn't very lucrative. Until very recently, the prices of flu vaccine were just a few dollars. Investing in new approaches to make a flu vaccine requires a significant expense.

NJ: What is the government doing to help companies make these transitions?

Gellin: A year ago we awarded a $97 million five-year contract to Sanofi specifically to accelerate the development of cell-based vaccine, to bring such a vaccine to the United States. That project is moving along, but we also recognize the need to increase the number of manufacturers. The appropriation provided by Congress in December allows us to build on this effort. We are in the final stages of evaluation and negotiation of proposals from a number of other companies.

NJ: How much should the government be helping drugmakers with their vaccine business?

Gellin: You can't build a business based on a pandemic market, so this is clearly an area where the government must help. The government is helping with equipment, designing facilities, clinical trials. So right now, we're doing all the things we can, short of building facilities. The government is making sure there are as many different approaches as possible to look at.