Sanofi, a worldwide pharmaceutical company have cut the cost of a course of rifapentine by 66%, from $45 to $15. This follows an international agreement made between Sanofi and Unitaid, a group who fund the worldwide prevention of AIDS, tuberculosis and malaria by working with pharmaceutical companies. This deal was specifically made to help prevent cases of latent tuberculosis. These are cases where patients show very subtle or no symptoms, and are not contagious. Between 85 and 170 million of these cases per year will develop into active tuberculosis, which is the more aggressive form that most people are aware of.
Rifapentine, often sold commercially as Priftin, is an antibiotic used in the treatment of both latent and active tuberculosis, and is always used as one part of a much broader course of antimycobacterial treatment. In the case of latent TB, this is often combined with another drug called isoniazid, which stops production of tuberculosis cell walls.
The action of rifapentine itself prevents bacterial RNA production. Rifapentine is able to do this because has it strongly binds to the active sites of RNA polymerase, the enzyme responsible for producing RNA. The reason this is a particularly effective treatment is due to rifapentine also having a very low binding ability to the enzymes similar to RNA polymerase in mammals, preventing any unwanted inhibition. In cases of latent TB, this will stop the development of cells as they can no longer synthesise proteins.
The implications of this are global . With this treatment and others like it becoming cheaper on a global scale, they will become more widely accessible for less economically developed countries, where expensive treatments are less readily available for those with average income. What’s more promising is that in 2015, the price in the USA was between $100 and $150, so this reduction of price is setting an incredible trend.
Regarding TB’s increasing resistance to most antibiotic treatments, this reduction in price is a short term solution at best. Provided that one of the main contributors to the rise of antibiotic resistant TB are patients not completing courses of antibiotics, more available treatments may only temporarily fix or in fact inflame the problem if the result is more incomplete courses. Ultimately, prevention would be a much more permanent solution to rising cases of TB.
