TB 'Superbug' Case Highlights New-Drug Void
With the whole world wagging its collective finger at Andrew Speaker--the TB-infected lawyer who triggered a global health scare last week when word got out that he had boarded seven commercial airline flights for his European wedding and honeymoon--a new report highlights why drug development has stalled in this area.
The 31-year-old Speaker was diagnosed with extreme drug resistant (XDR) tuberculosis, a potentially deadly bacterial strain that does not respond to at least three of the six classes of second-line TB drugs. But because the market for new treatments for XDR TB is tiny, drug makers can hope to recoup a mere fraction of the cost of R&D.
TB Alliance's "Pathway to Patients" report, compiled with IMS Health, was released May 14--two weeks before the media firestorm hit Speaker. But Nina Schwalbe, director of policy for the not-for-profit drug developer, noted that there's still a connection to be made. "[The media coverage] needs to put attention on the fact that there have been no new drugs in 40 years," she said. "Right now, a major failing is drug resistance."
The market for the four first-line TB drugs is $315 million a year, according to the report, and that number is static. Even if all patients with the disease were treated with the most expensive agents, the market would still reach a ceiling of just $418 million. "It's small because the regimens are inexpensive," Schwalbe said. "It doesn't seem to be a profit-making venture."
For second-line treatments, meanwhile, the market is only $54 million a year. But despite the fact that unmet need persists, that market is growing only sluggishly. "There's slow potential to scale up," Schwalbe said. "It would be hard to believe that an incredibly expensive drug could sell at an incredibly expensive price in developing nations." The challenge of second-line therapies also includes getting drugs to patients; a typical regimen lasts at least two years and can have a dizzying array of side effects.
Schwalbe also noted that it's misleading to call the sale of TB drugs a true "market." The majority of products are purchased by national governments and distributed locally, while in certain countries, such as India, 75 percent of sales come from the private sector. "The TB drug market is fragmented and complicated," Schwalbe said, adding that these harsh realities have kept drug firms from investing in R&D for products that work faster with fewer side effects.
TB Alliance--which works with companies like Bayer, GlaxoSmithKline, and Novartis as well as the Bill & Melinda Gates Foundation--is one of a growing number of public-private partnerships dedicated to neglected diseases. "This is going to have to be a group effort," Schwalbe said.
Meantime, Speaker, in quarantine since May 25, has started on a carefully selected three-drug drug regimen that his doctors admit is something of a crapshoot. Should the treatment fail to kill the superbug, his tennis-ball-size lung infection may be removed surgically--not exactly the most cost-effective global solution to the XDR-TB riddle.
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