TB drugs in the hand of a patient in Ethiopia

WHO/TDR/Crump

[SINGAPORE] The Novartis Institute for Tropical Diseases (NITD) and the Global Alliance for Tuberculosis Drug Development (TB Alliance) have announced their collaboration on a research programme to develop drugs for the treatment of tuberculosis (TB).

The potential drugs are in a class of chemical compounds called nitroimidazopyrans. These chemicals have stirred the TB drug development scene since 2000, when one particular compound in the class — named PA-824 — showed potent activity against Mycobacterium tuberculosis, the bacterium responsible for TB.

Tuberculosis is a bacterial infection of the lungs that spreads by droplet infection. In 2002, it claimed two million lives worldwide, with the greatest number of deaths occurring in South-East Asia. In HIV-infected patients, whose immune systems are weakened, TB is the leading cause of death.

PA-824 is effective in both active and latent TB infections. More importantly, it is effective against TB infections that are resistant to many existing drugs.

The aim of the joint research program is to identify the next generation of nitroimidazopyran compounds related to PA-824. A modified form of the compound could result in a drug whose required dosage is easier to comply with than current TB drug regimes, which require patients to take medication for as many as six to nine months.

Both NITD and TB Alliance have research and development roles in the planned collaboration. The candidate drug PA-824, meanwhile, is scheduled to enter the first clinical trials in the first half of 2005.

There have been no new drugs against TB for the last 30 years. This is partly because drug companies have tended to focus their research and development efforts away from developing countries, where patients cannot afford expensive drugs.

By partnering the TB Alliance, NITD has committed the Novartis Group to make the resulting TB drugs available to patients, without a profit, in developing countries where TB is endemic.

"New drugs are initially expensive and that is understandable because of the research investment involved," Charles Yu, the newly elected president of the TB Alliance's TB stakeholders association told SciDev.Net. "The TB Alliance is unique in its asking of companies to make TB drugs available, affordable and accessible."

Gwynne Oosterbaan, assistant director of public affairs and advocacy at the TB Alliance, told SciDev.Net that both it and the NITD would contribute funds, materials and personnel towards the intial joint research programme.

"We expect the first phase of the partnership, with a goal of identifying a new lead compound, to last one to two years," says Oosterbaan. "The programme will be evaluated regularly."

The TB Alliance is a not-for-profit organisation that enlists both the public and private sectors in the development of drugs for TB. Its latest collaboration with NITD will also involve contributions from scientists at the US National Institutes of Allergy and Infectious Disease.