MORE TREATMENTS
While vaccines to prevent disease are the holy grail for tackling global health problems, a number of initiatives support
development of new treatments for tuberculosis (TB), malaria, and multiple neglected diseases that cripple third-world countries.
Efforts to combat multi-drug resistant (MDR) and extensively-drug resistant (XDR) TB strains is high on the global research
agenda and has attracted considerable attention at the FDA. Efforts to streamline clinical research approaches for TB drugs
could expand under Commissioner Margaret Hamburg, who launched a major TB control campaign when head of New York City's public
health department in the 1990s.
An FDA advisory committee meeting in June discussed early trial endpoints for drugs to treat MDR TB, such as reduced bacterial
count in sputum culture, followed by confirmatory trials to document low relapse rates, to accelerate the R&D process. The
FDA followed up with a July workshop that examined noninferiority study designs, combination therapy regimens, and missing
data issues for research involving drug-susceptible TB. Sequella Chief Medical Officer Gary Horwith urged consideration of
Phase 0 and adaptive clinical trials and surrogate endpoints, and Gail Cassell of Eli Lilly advocated "boldness in clinical
trial design."
Because there will always be limits on funds available to support costly clinical trails, the neglected disease community
is testing the stimulus power of market-based "pull" mechanisms, such as advance market commitments (AMCs) that guarantee
prices for new vaccines and drugs with low profit potential in the US or Europe. This approach is being used to fight malaria
by subsidizing the purchase of artemisinin-based combination therapies (ACTs) that are effective, but too costly for most
third-world health programs. By expanding the market for these more effective therapies, the program aims to encourage the
production of quality ACTs and drive older, ineffective products out of the market.
Another AMC project supports the development of new pneumococcal vaccines that can protect against pneumonia and other diseases
that claim the lives of millions of children each year. A broad coalition of public and private donors has committed $1.5
billion to guarantee a price for a vaccine suitable for third-world use, while also encouraging companies to invest more broadly
in research and expanded manufacturing capacity for effective vaccines.
The FDA's priority review voucher initiative offers another type of inducement for manufacturers to support R&D of neglected
disease treatments. The program provides a voucher to sponsors seeking approval of a treatment for one of 16 designated tropical
diseases. The voucher is good for a future priority, six-month review (instead of the usual 10 months or more), which should
be highly lucrative to any company seeking market approval for a new medicine with a large sales potential.
The first voucher was recently awarded to Novartis in conjunction with approval of its antimalarial drug Coartem (artemether-lumefantrine)
in the US. The drug already was available in most of the world, but the application got the program going while the FDA develops
guidance and weighs whether to expand the list of topical diseases that qualify for review vouchers. Several manufacturers
appear poised to file applications, with the hope of gaining vouchers they can use or sell to support speedy drug approvals.
Jill Wechsler is BioPharm International's Washington editor, Chevy Chase, MD, 301.656.4634, jwechsler@advanstar.com
|
