A new TB drug with a novel mechanism of action – delamanid – is now available for treatment of adults with multidrug-resistant tuberculosis (MDR-TB), a form of tuberculosis resistant to isoniazid and rifampicin, the main first-line TB drugs.

Although the drug was granted conditional approval by the European Medicine Agency in April 2014, the World Health Organisation, WHO, has issued “interim policy guidance” that lists five conditions that must be in place if delamanid is used to treat adults with MDR-TB:

Among the conditions is proper patient inclusion: Special caution is required when delamanid is used in people aged 65 and over, in adults living with HIV, patients with diabetes, hepatic or severe renal impairment, or those who use alcohol or substances. Use in pregnant and breastfeeding women and children is not advised.

Adherence: Also to be met is adherence to WHO recommendations when designing MDR-TB treatment regimens. WHO says when delamanid is included in treatment, all principles on which WHO-recommended MDR-TB treatment regimens are based must be followed, particularly the inclusion of four effective second-line drugs as well as pyrazinamide. Delamanid should not be introduced alone into a regimen in which the companion drugs are failing to show effectiveness.

Others are effective treatment and monitoring. Treatment must be closely monitored for effectiveness and safety, using sound treatment and management protocols that have been approved by the relevant national authorities. Pharmacovigilance and management of adverse events: active pharmacovigilance measures must be in place to ensure early detection and proper management of adverse drug reactions and potential interactions with other drugs.

Informed consent: Patients must be fully aware of the potential benefits and harms of the new drug, and give informed consent before embarking on treatment

WHO strongly recommends the acceleration of Phase III trials to generate a more comprehensive evidence base to inform future policy on delamanid.

WHO will review, revise, or update the interim guidance as additional information on efficacy and safety become available.