The federal government has approved tests of an experimental and potentially expensive AIDS drug that could prolong the lives of patients with drug-resistant strains of HIV.
Dubbed Fuzeon by its developers, Roche Group and Trimeris Inc., the drug won a priority, six-month review from the Food and Drug Administration. The companies hope to put Fuzeon on the market by spring.
"Everyone is so pleased about the drug itself," said Martin Delaney, founding director of Project Inform, an advocacy organization. "It is such a significant development. But we are terribly apprehensive about the cost."
Roche, based in Switzerland, and Trimeris, of Durham, N.C., won't discuss pricing details until the drug is approved, but say Fuzeon is complicated to produce and will be expensive. Experts predict a cost of $10,000 to $15,000 a year per patient.
The most expensive AIDS drugs now available cost about $7,500 a year, although some combination treatments approach $15,000 in annual costs.
Fuzeon's cost should be kept in perspective, said Dr. James Thommes, the drug's medical director at Roche, saying that it keeps people from expensive hospital stays and prolongs their lives.
"No one wants drug companies to stop looking at ways to treat AIDS" because of expense issues, he said.
Cash-strapped AIDS assistance programs are already worried they might not be able to afford Fuzeon. Roche and Trimeris also have said they may not be able to make enough Fuzeon to meet initial demand.
The drug is the first in a class known as fusion inhibitors, which are designed to block HIV from entering blood cells. It acts on the third stage of that entry process, known as fusion.
Fuzeon's journey to the marketplace exemplifies the challenges of transforming innovative science into a drug that fits into a complex web of production, pricing and patient demands.
Roche began outfitting a plant to produce Fuzeon two years ago, when only one 28-patient study on its effectiveness was completed. The companies knew Fuzeon had promise but couldn't know how it would perform in large trials.
The plant was set up to produce enough Fuzeon for 25,000 patients by the end of 2003 and 40,000 patients by 2004.
Now, it looks like demand will be greater.
It is unclear how many of the 850,000 to 950,000 Americans infected with the virus have a drug-resistant form. Resistance often becomes a problem after people start taking AIDS medicines.
A recent study in the New England Journal of Medicine found that the number of newly infected people with resistance to one drug increased threefold from 1995 to 2000, to 12.4 percent. A study by the Department of Veterans Affairs released last December found that 78 percent of the 1,647 people they tested showed resistance to one or more AIDS drugs.
Clinical tests showed that when Fuzeon was added to the regimen of patients with drug resistance, they were twice as likely to have virus concentrations decrease below detectable levels than those who didn't add the medicine.
Fuzeon was discovered by two researchers at Duke University, Dani Bolognesi and Tom Matthews, who then founded Trimeris.
Fuzeon is a large, complex peptide, or string of amino acids, that is difficult to manufacture and must be taken by injection twice daily. Most drugs are small molecules that are easier to produce and can be taken orally.
"We knew we'd have challenges in cost and production, but what was the alternative?" Bolognesi said. "The important thing is there is a new AIDS drug."
As they struggle with the already high cost of existing drugs, AIDS assistance programs in 11 states have closed enrollment or limited access because of budget constraints. The programs provide care to those who can't afford it using state and federal money, and illustrate how cost is a factor not just in poor countries, where pharmaceutical firms have been pressured to reduce prices.
When Fuzeon becomes available, "no one knows how they are going to afford to pay for this," said Bill Arnold, chairman of the ADAP Working Group, an advocacy organization for the programs.
Activists are seeking an accounting of costs from the manufacturers. They are concerned the makers might try to make as much profit as possible before other drugs arrive. Merck and Schering-Plough are developing another class of AIDS drugs that can be taken orally.
Bolognesi thinks activists' concerns about Fuzeon's price are premature because it is still unclear how the drug will fit into the current treatment mix. It may wind up replacing one or two drugs in a patient's regimen, so the total treatment cost might not jump significantly, he said.