Superbugs: Where Are the Wonder Drugs?
The latest threat to America's health is a drug-resistant strain of bacteria, Streptococcus pneumoniae, that causes ear infections in children as well as pneumonia and meningitis in adults. It was first spotted in Czechoslovakia 20 years ago and wended its way across Europe, growing steadily resistant to more and more antibiotics. The latest and scariest sighting: Nine children in Rochester, N.Y., came down with a strain that shrugs off all 18 antibiotics approved for kids. The Rochester doctors who found the bug beat it into submission with Johnson & Johnson's (JNJ ) Levaquin, a drug for adults, but only after it left one child with permanent hearing loss.
This strain of S. pneumoniae is just one of several deadly superbugs on doctors' radar screens. But the number of new classes of antibiotics nearing the market to combat these pathogens is exactly zero. That's in keeping with the trend line of the past 20 years: Food & Drug Administration approvals of new antibacterials have fallen from 16 launched in 1983-87 to just 2 in the past five years.
The problem, say drug companies, is that antibiotics aren't very profitable. It can take up to 10 years and some $800 million to create a new drug, but it's tough to recover those costs, given that a course of antibiotics is usually prescribed just once, for 7 to 10 days. Then there's the antibiotic Catch-22: Doctors tend to limit prescriptions of new drugs for all but the most dire infections in order to delay the emergence of resistant strains. "What's good for the public health is a real disincentive for antibiotic development," says Dr. Barry I. Eisenstein, head of scientific affairs at Cubist Pharmaceuticals (CBST ).
Eisenstein knows whereof he speaks; Cubicin, introduced by Cubist in 2003, is the most powerful antibiotic to come along in years, but doctors use it only as a last resort. Analysts have projected peak annual sales of $500 million for Cubicin. Contrast that with the $13 billion that Pfizer's (PFE ) cholesterol-lowering drug Lipitor raked in last year.
Still, society needs new antibiotics as much as it needs new statins. The Centers for Disease Control & Prevention (CDC) just reported that a dangerous drug-resistant staph infection, MRSA (methicillin-resistant Staphylococcus aureus), has rapidly spread from hospital patients to the larger community. The CDC estimates that 94,360 people in the U.S. contracted MRSA in 2005, and 18,650 of them died.
Coming up with a weapon is hard science. Antibiotics introduced during the past 60 years were discovered by screening chemicals found in nature, a painstaking process. Newer research seeks to reverse-engineer pathogens to produce customized antibiotics, but this approach is in its early stages. It doesn't help that rapidly mutating pathogens present a constantly moving target.
On Sept. 27, Representatives Jim Matheson (D-Utah) and Michael Ferguson (R-N.J.) introduced the Strategies to Address Antimicrobial Resistance Act, meant to provide incentives for antibiotic development. Robert Guidos, director of public policy for the Infectious Diseases Society of America, says he thinks the bill's prospects are excellent. "We keep hearing from staff on the Hill and congressmen whose relatives have had MRSA infections," he says. "This is not a polarizing issue."
The problem with antibiotics is that they're so hard to develop, as the October issue of The Scientist explains in "An Antibiotic to the Rescue." It chronicles Cubist Pharmaceuticals' (CBST ) struggle to win FDA approval for the powerful drug Cubicin, which finally got the nod for skin infections in 2003.
For a history of pathogens that have escaped from hospitals into the community, see "Superbugs Bite Back," in the Sept. 29 NewScientist. One scary tidbit: A scientist speculates that MRSA could piggyback onto an avian flu pandemic, resulting in "a nightmare scenario" for the whole world.
By Catherine Arnst