Wednesday, August 15, 2007

NPR on Generic Biologics

Interesting story done by NPR on the generic biologics issue.


http://www.npr.org/templates/story/story.php?storyId=12638437

Health & Science
Are Generic Biotech Drugs Coming Soon?

Listen to this story... by Joanne Silberner

Correction: At the time this story aired neither the House nor Senate had voted on legislation. There have been two hearings in subcommittees of the House of Representatives, and a Senate committee has approved legislation.

All Things Considered, August 9, 2007 · While Congress is away this month, House and Senate staffers are working on a bill aimed at helping patients who rely on innovative biotech drugs that can cost as much as several thousand dollars per month.

Generic versions of the drugs would surely be cheaper, but opponents of generic versions say that making sure the knockoffs are safe and effective may be trickier than it sounds.

Donna Gosbee, 51, came from Wyoming to Washington, D.C., to attend a meeting of the Multiple Sclerosis Society. She is using a walker.

"I never know from one day to the next until I put my feet down on the floor whether I'm going to be able to walk," Gosbee says.

Gosbee was diagnosed with multiple sclerosis four years ago.

"The doctors put me on one of the biologics, Betaseron," she says. "I've been on it for three years now and this drug costs $1,500 a month."

The government helps Gosbee with some of the cost, but she's worried the help won't always be there. So she came to Washington to lobby Congress.

Lobbying for Change

"I'm going to talk to Wyoming legislators to try to convince them that medications are just out of reach of the normal person," Gosbee says.

A generic could significantly cut her medical bill. At www.drugstore.com, for example, the generic version of the statin drug, Mevacor, is only one-third of Mevacor's price.

But Gosbee's drug is manufactured very differently — by living, bioengineered cells.

They make molecules that are much bigger than most conventional drugs, and a lot more complex, says Roger Williams, CEO of U.S. Pharmacopeia, a nonprofit organization that sets standards for drug manufacturers.

"If I showed you on a page the molecular structure of a biologic, it might cover two pages just of carbons and nitrogens and hydrogens and oxygens," Williams says.

In contrast, he says the structure of many conventional drugs fill less than half a page.

Williams says making conventional drugs is like snapping together Tinker Toys. You add one chemical after another, and the manufacturer is very much in control.

Making a biotech drug is more like farming. You start with a living cell, then keep the temperature, the nutrients and other growing conditions just right. Just as wheat grown from a different seed stock or under different conditions will produce slightly different grain, different versions of biotech drugs can vary — even when made by the same company.

The Process of Biotech

In Gaithersburg, Md., a company called MedImmune makes the biotech drug Synagis. The drug fights a virus called RSV that can kill premature babies.

Just getting into MedImmune takes work — you have to put on gloves, booties and a double set of what look like surgical scrubs.

You must also go through multiple airlocks. Sterility is important for conventional drugs, too, but it's especially important here. If bacteria or viruses get into the cell cultures, they could disrupt the manufacturing process and wind up in the final drug.

Workers take large beakers of living cells in culture from a refrigerator. The cells go into gleaming metal vats the size of small cars.

"This is the start of our bioreactor train," explains Tony Luttrell, MedImmune's vice president.

There are enough pressure monitors and temperature gauges and pipes to make a science-fiction movie proud.

Conventional manufacturers use temperature gauges too, as well as vats filled with buckets of chemicals.

But these biotech vats hold mouse cells, each one loaded up with human DNA. The human DNA is directing the cells to produce a particular protein — an antibody that can fight RSV.

If you want to make a copy of MedImmune's drug, you would have to insert some human DNA into mouse cells in a precise way — a way that will produce that protein. It's a real challenge.

"One little genetic change, one little change in the way the protein is configured or the way the proteins fold onto each other may have an effect on how it actually acts in the clinic," Luttrell says.

Then you have to be really careful about how you grow the cells, Williams says. For example, temperature can make a big difference. Look at albumen — the protein in egg whites.

"If you take egg white and cook it, that's OK to eat, but it's no good to the chicken anymore," Williams says.

Generic Outlook

Williams thinks some biotech drugs could be made generically. But the only way to know for sure that a different version would be just as safe and effective is to perform lengthy and expensive testing in animals or people — something that's not required for conventional generics.

There have been two hearings in subcommittees of the House of Represenatives, and a Senate committee has approved legislation. Staffers are now working to develop legislation that can win approval.

But don't hold your breath — companies that make brand name drugs are still adamant that testing in people should be required.

Patients and generic companies waiting for less expensive drugs aren't happy either. Both bills would make generic companies wait 12 years before they could market a cheaper drug, not much different from conventional generics, but a long time when you're spending several thousand dollars a month to fill a prescription.

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