By Willy Ngumbi

Two new pricing agreements that will drastically lower the price of tuberculosis (TB) prevention treatments in 138 low- and middle-income countries have been launched.

The new agreements led by Unitaid, MedAccess, Aurum Institute and the Clinton Health Access Initiative (CHAI) aim to make rifapentine-based TB prevention treatment regimens more widely available and affordable by bringing in a second generic manufacturer of a fixed dose combination of a three-month, once-weekly oral treatment (3HP), as well as single tablets of rifapentine, which are used in combination with isoniazid 300 mg for a one-month, once-daily oral treatment (1HP).

“Since 2018, the World Health Organization(WHO) has recommended a shorter rifapentine based TB prevention treatment regimen, known as 1HP, but we’ve seen little uptake,” said Prof Gavin Churchyard, IMPAACT4TB Principal Investigator and Aurum Group Chief Executive Officer (CEO).

“The 1HP regimen consists of only one month of daily isoniazid and rifapentine, but is slightly more expensive. This new funding will allow us to understand patient acceptability, tolerance and preference of 1HP in comparison to 3HP.”

“In recent years, we’ve come a long way towards improving access, at an affordable cost, to tuberculosis-prevention treatments that are shorter and easier to take, but supply has remained a constraint,” said Dr Matteo Zignol, WHO Global Tuberculosis Programme. “This announcement will help us prevent TB among more people by ensuring that there is enough supply to meet the needs of eligible countries. Ultimately, preventing TB is critical to our ability to finally end this deadly disease.”

Unitaid will provide additional funding to the IMPAACT4TB Consortium, a considerable amount of US$20 million to support the continued introduction of short course, rifapentine-based TB prevention treatment regimens around the globe.

The funding awarded to the Aurum Institute will build on the momentum created by the IMPAACT4TB Consortium over the past five years focusing specifically on evidence required to ensure that children and pregnant women, including those living with HIV, and household contacts have access to the latest TB prevention regimens.

“To date, the world has fallen behind in reaching children with short-course, rifapentine-based TB prevention regimens,” said Prof Gavin Churchyard, IMPAACT4TB Principal Investigator and Aurum Group CEO. “This new funding will build on the successes of the IMPAACT4TB program, and allow us to fill the major evidence gaps that exist when it comes to preventing TB in children living with HIV, as well as in HIV positive pregnant women.”

The additional funding will help identify the correct dosing and drug-to-drug interactions when children and pregnant women living with HIV take three months of weekly isoniazid and rifapentine—or 3HP—combined with dolutegravir (DTG) based Anti-Retroviral Therapy.

The costed extension will fund three studies to help fill these evidence gaps: one in HIV positive pregnant women in South Africa (DOLPHIN MOMS); one in children living with HIV in South Africa who are taking DTG (DOLPHIN KIDS); and one comparing the use of 1HP to 3HP in South Africa, Mozambique, India and Indonesia (one to three).

“We expect this desperately needed child-friendly formulation to be ready for distribution by no later than the end of 2024,” said Mike Frick from the Treatment Action Group (TAG). “To ensure countries are prepared to order these new regimens once they are ready, we’re already starting to raise awareness among communities and eligible populations that currently do not have access to optimal TPT regimens.”

Alongside evidence generation, the project will invest in ensuring countries are aware of the need for medicines for children for TB prevention that are easier to swallow and with the appropriate dose.

Currently, 3HP tablets need to be swallowed whole which is difficult for some children and need to be broken into pieces to dose children appropriately limiting access to TB prevention for children. Once new formulations are ready, governments will in turn need to be ready to introduce them.

About one quarter of the world’s population is infected with a latent form of TB that causes no symptoms and is not contagious which if not treated, up to 10% of those infected will develop active TB causing severe illness and can be transmitted from person to person through the air.