The recent agreement between Bayer and the TB Alliance offers a remarkable example of the industry embracing the spirit of
wider access. Bayer has turned over its $500-million-a-year antibiotic moxifloxacin to the organization to test in clinical
trials. If proven effective, Bayer will offer "expansive access" to the drug, despite the risk of the deal undercutting profits
on the commercial side. Sources even say Bayer will allow the TB Alliance to check its books to ensure they are offering it
at no profit. Says Freire: "I don't know of any other pharma company that has said, 'Yeah, we trust our drug, and yes, we
are making a commitment to public health, and yes, we're going to make it affordable. And okay, maybe there's a risk of drugs
coming back out [through diversion], but we don't believe so. So we're going to do it because it's the right thing to do.'"
DOTS-Plus: The Next Line of Defense
When it comes to multi-drug-resistant tuberculosis (MDR-TB), people are seeking second-line treatments where first-line defenses
left off more than half a century ago. Streptomycin, the first TB drug, has become a second-line drug of desperation.
It's a first-line drug, but not often used because it must be given by injections, says Fabienne Jouberton, procurement officer
for WHO's Stop TB department. But it's often used that way in Temeke. Given the scarce alternatives, local rules apply. "Once
you have resistance, you're going to use everything you can to cure the patient," says Young.
A patient waiting for his streptomycin treatment pulls down his pants, and slaps his right side, where he wants to receive
today's shot. The injection is not only a strain on the resources at the clinic, it's an added expense: Although the TB drugs
are free, the syringe is not, and he struggles to pay about 50 cents each day for a new one.
At the moment, most of the world's known cases of MDR-TB are in China, India, and Russia, where drugs were available early
on and where compliance was a widespread problem. WHO believes that an MDR-TB epidemic won't be a problem in the near future
for Africa, given the late introduction of rifampicin. But epidemiologists are debating over the transmissibility of certain
drug-resistant strains. "The information we have for Africa is still very patchy," says Ernesto Jaramillo, a medical officer
in WHO's TB/HIV drug resistance division.
In fact, some researchers are concluding that MDR-TB may be more advanced in Africa than previously thought. "In Africa, there's
not a lot of surveillance for drug resistance because it requires drug sensitivity testing—which is not included in routine
TB care," says Megan Murray, assistant professor of epidemiology at the Harvard School of Public Health, "With our surveillance
study, we found outbreaks of highly drug-resistant strains that seem very infectious. Our predictions from mathematical models
are that those mutations will proliferate and eventually dominate. It will take a while—maybe even decades—but if we don't
focus on MDR-TB, we're going to see a rise, and even a replacement of, drug-sensitive TB."
In other parts of the world that have more advanced drug resistance, clinicians have begun using newer second-line treatments,
including capreomycin and cycloserine. At one time, such therapies were quite expensive, costing up to $33,000 per patient,
according to the CDC Foundation. They also have significant compliance challenges: MDR-TB drugs are more toxic and require
18- to 24-month treatments.
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