Sunday, May 3, 2009

How to Make Better Vaccines--Quickly

How to Make Better Vaccines--Quickly. By Scott Gottlieb, M.D.
Forbes.com, April 30, 2009

So far the swine flu infections in the U.S. have been mostly mild. But if the virus should continue to spread, or the infections worsen, rapid development of a vaccine could be our best protection.
The ability to make a vaccine quickly isn't easy, but we're better able to do it today than just five years ago. This is because we've taken steps to improve our ability to thwart biological threats: both the naturally occurring kind, like swine flu, and even the ones that could be used deliberately as weapons.

It's especially true in the vaccine industry, which has undergone a renaissance in recent years partly as a result of government incentives and improvements in how vaccines are regulated. These policy steps have improved our medical footing and are worth bearing in mind as we deal with swine flu.

But we still face a lot of vulnerabilities. These come not only from nature, but also from Washington, where some of these steps to build our vaccine capacity remain deeply unfashionable.

Vaccines were long seen as commodity products, marked by little new investment. The sector made vaccines that reflected little innovation and sold them cheaply, mostly to government agencies that valued low price--enabling wider use--over advances in how vaccines worked or were manufactured.

The end result was a skeleton industry with few reliable suppliers. Flu vaccines, in particular, were made by the same process used for 50 years--by being grown inside chicken eggs--despite advances in science that enable ordinary animal cells to be turned into more reliable incubators.

The chicken egg process is dirty, slow and expensive; it costs more than $300 million to build a new plant and requires about five years to bring it on line. Using eggs, simply creating a novel production run to target a new strain like swine flu can take four to six months. (First the "wild" virus needs to be converted into a weaker "seed" strain, which can grow inside the eggs without killing them.)

This is a rate-limiting step we are still mastering when it comes to swine flu. By comparison, using the cell-based technology, a vaccine could theoretically be produced in a matter of weeks.
Over the last five years, the vaccine market has re-emerged as a key industry and a growing business for the large drug firms, which have invested heavily in better ways to make these products.

These investments are a result of both rising profit margins for these products and the success of several consumer vaccines. But it's also a consequence of legislation that created new incentives to develop these products and practical regulatory changes at the Food and Drug Administration (FDA) that lowered development risks by applying better scientific tools to how vaccines are evaluated.

This includes a series of key "guidance" documents the FDA's biologics center issued, mapping out a streamlined development process for the approval of flu vaccines. It relied on more rapid measures of benefit from tests against biological markers that gauge immune response to the vaccine. These measures reduced the cost of developing the vaccine and created more predictability for new vaccine developers.

Among other steps, the FDA put in place an express inspection process for certifying new vaccine manufacturing facilities. The agency also worked with manufacturers to help them develop the new cell-based vaccine technology. This process could be especially important for making vaccines against a potentially virulent form of pandemic flu that might not be efficient or even possible to manufacture using older, egg-based production methods.

Taken together, these regulatory steps gave rise to new vaccine products that give today's policymakers many more options for responding to the swine flu problem.

The Department of Health and Human Services also established a process for making and contracting government grants for vaccines (under its BioShield program) for medical products that could protect against biological weapons and other threats. One contract, for $487 million, was awarded three months ago for construction of the first U.S. facility to manufacture cell-based flu vaccines.

If we had to widely distribute a vaccine against a pandemic flu, the cell-based process could be used in a pinch. But so few of these worldwide facilities are operational--and, thus far, none are approved by the FDA. So right now, we'll need to rely on the egg-based process that takes four to six months.

But today there are three times as many manufacturers licensed to make flu vaccines as there were just four years ago. This means we could make swine flu vaccines with the egg process without using up too much of the egg stock reserved for making next year's seasonal flu vaccines.

Another option to boost supply is to use an adjuvant, which is basically a vaccine additive that makes a smaller amount of vaccine more effective. It lets you stretch your vaccine supply.

Right now, there are adjuvants approved in Europe that could be used in a swine flu vaccine, but none are approved in the U.S. There's reason to believe this adjuvant--already used in Europe for a vaccine against avian flu as well as human papilloma virus (HPV)--could boost supply of a swine flu vaccine as much as five-fold. The FDA needs to rapidly assess this vaccine additive and make a decision if it will use it in this case. There is ample experience in Europe to draw from.

Our improved preparedness is not a sure thing, nor are continued advances in vaccines that can reduce risks. One reason is diminishing incentives for investment in the industrial capacity to make these things.

As a result of legislative endeavors favoring generics and lower drug costs, the average patent life on big new drugs has been reduced to as little as 10 years from more than 12 just nine years ago. These measures improve access to the drugs but reduce incentives to invest in new plants and technology. There's legislation right now on Capitol Hill, sponsored by Congressman Henry Waxman, D-Calif., that would reduce the effective patent life on "biologics" like vaccines to as little as five years.

In addition, there's political pressure on the FDA to increase regulatory hurdles to "promote drug safety." Some of these efforts undermine steps the FDA has taken to modernize regulation of vaccines. There's still work to be done to improve regulation further and enhance our preparedness for pandemic. The cell-based manufacturing processes, for example, as well as the approval of adjuvants, should become regulatory priorities for the FDA.

Preparing for future threats requires a broad armamentarium and the residual capacity to create new things quickly. We are better prepared to respond to swine flu as a consequence of these lessons. But this strategic capacity doesn't come cheap, and we need to strike a careful balance between policies that enable better access to today's medicines and incentives that invest in tomorrow's. As the biology of threats like swine flu grow more complex, it's not a sure thing our medical industry will be robust enough to keep pace with it.

Scott Gottlieb, M.D., is a resident fellow at AEI.

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