The World Health Organization (WHO) has added four tuberculosis (TB) drugs to its list of prequalified products. Manufactured by generic drugmaker MacLeods, these medicines will increase the choice of quality products available to procurement agencies to tackle the disease, the agency said.

WHO prequalification facilitates access to drugs that meet unified standards of quality, safety and efficacy for treating HIV/AIDS, malaria and TB. The four new drugs are the first new TB products to be added to the list of prequalified medicines in two years. They will help scale up anti-TB efforts in countries with high incidence of the disease. According to WHO, TB is more prevalent in sub-Saharan Africa than almost anywhere else.

One of the products, Cycloserine, is particularly important because it is a second-line medicine, necessary to treat tuberculosis that is resistant to standard drugs. Cycloserine is the first such product to be included on the list. There is also a fixed-dose combination -- ethambutol plus isoniazid -- which is the first product combining these two basic medicines to be prequalified. The other two drugs are Ethambutol and Pyrazinamide.

Data on the quality and bioequivalence of these newly prequalified products and facility inspection findings will soon be published. These procedures make the WHO prequalification process one of the most transparent quality assurance programs, the agency said.