Drug Resistant TB Treatment Efforts Under Threat says MSF

By Michael Gwarisa

Doctors Without Borders/Médecins Sans Frontières (MSF) says limited access to to new drug delamanid reduces promising treatment options available for those with drug-resistant tuberculosis.

According to MSF, almost three quarters (74%) of patients receiving a combination of these drugs for six months achieved ‘culture conversion’, an early indicator that treatment might ultimately be successful.

“The WHO endorses delamanid to replace the injectable agent for children and adolescents with DR-TB in cases of intolerance or resistance to some drugs, giving this group an option that is more effective and less toxic than standard treatment. As MSF, we attempt to offer delamanid as a primary option for children and adolescents with DR-TB whenever feasible, in order to avoid the risk of side effects from the injectable drugs.

“Delamanid can also strengthen the treatment regimen for more complex cases, such as people with XDR-TB, or DR-TB patients who are living with other chronic diseases like diabetes, or HIV. It is a good option for HIV co-infected patients because it doesn’t require patients to change their antiretroviral treatment,” aid MSF DR-TB Doctor Anja Reuter, based in Khayelitsha.

Today MSF will publish early data on the use of two new TB drugs, delamanid and bedaquiline among patients living with drug resistant TB in Khayelitsha, Western Cape.

MSF estimates that each year at least 7,000 DR-TB patients in South Africa could benefit from delamanid, but access currently remains limited. The National Department of Health launch of the Delamanid Clinical Access Programme (DCAP) in March 2017 was a progressive step forward, although uptake has been much slower than expected, with only 10 of the 400 treatment courses pledged by pharmaceutical manufacturer Otsuka allocated to date.

This is in part due to the fact that the eligibility criteria currently exclude people with XDR-TB, and patients on bedaquiline. South Africa’s Medicines Control Council (MCC) is currently reviewing a revised protocol that would expand DCAP eligibility to these groups, as well as a dossier to fully register delamanid in South Africa.

“It is imperative that the MCC take urgent action to help expand access to delamanid,” says Reuter.

“When products are registered, access improves. The Bedaquiline Clinical Access Program started just over 200 patients in two years, but in the two years since registration and introduction into national guidelines, South Africa has initiated over 6,700 patients on bedaquiline. We are pleased to know that the MCC is prioritizing a rapid review of delamanid for registration, and while registration is pending, we look forward to the MCC approving the expanded DCAP criteria so that currently excluded groups can benefit.”

However, little research exists regarding the use of the two drugs together but early results from Khayelitsha and the two international sites are promising says MSF indicating that after six months on treatment, 74% of 23 patients with either multidrug-resistant TB (MDR-TB) or extensively drug-resistant TB (XDR-TB) who had both drugs included in their treatment regimen achieved culture conversion – an early sign that treatment may ultimately be successful.

Cure rates for MDR-TB and XDR-TB are typically poor – 48% and 24% respectively in South Africa. The data also gives an early indication that combination use is safe.