WHO, however, warned that it does not have evidence on the safety and effectiveness of bedaquiline use beyond six months, as it was insufficient for review
The World Health Organisation recently placed the contentious bedaquiline in the list of 'priority' drugs used in treatment for people suffering with multi drug-resistant tuberculosis (MDR-TB).
Bedaquiline, along with levofloxacin/moxifloxacin and linezolid, has now been placed in Group A, which is for prioritised medicines. Under the previous guidelines, bedaquiline belonged to Group C, which is for drugs that can be used when patients develop resistance to Group-A and Group-B drugs.
WHO, however, warned that it does not have evidence on the safety and effectiveness of bedaquiline use beyond six months, as it was insufficient for review. Also, linezolid, a highly potent drug with severe side-effects, including temporary or permanent loss of hearing, may limit its use, WHO said.
WHO's evidence-based guidelines for the treatment of multidrug-resistant or rifampicin resistant tuberculosis (MDR/RR-TB) were published in October 2016. Subsequently, new evidence prompted a public call for data by WHO in anticipation of a formal review.
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The latest communication states that WHO no longer recommends use of kanamycin and capreomycin for TB patients due to the increased risk of treatment failure and relapse associated with their use.
It states that countries should not wait for existing stocks of Kanamycin to be exhausted and should immediately replace it with the relatively safer – amikacin, in the shorter regimen. Kanamycin use is discouraged due to instances of ototoxicity resulting in hearing loss.
Longer MDR-TB regimens usually last 18-20 months and may be standardised or individualised. These regimens are usually designed to include at least five medicines that are considered effective.
WHO said the position on another drug, delamanid, will be re-assessed once individual patient data from the Otsuka trial 213 has been reviewed.
Currently, US-based Johnson and Johnson's (J&J) Janssen holds the patents for producing bedaquiline, which expire in 2023.
Under the conditional access programme of the Indian government, bedaquiline imported from Janssen is being administered to around to 1,000 patients in the country.
Though there is no official survey, central government data suggests over 2,000 patients need the drug. Experts, however, say that the number may be much more, closer to 20,000 patients.
For some countries, including India, J&J recently cut the price of bedaquiline to $400 for six months of treatment. India has received the current stock through donations, but once it decides to scale up, it will have to start buying the drugs from J&J under the aegis of the Global Drug Facility.
In countries excluded from J&J's price cut list, the drug maker currently charges between $3,000 and $30,000 for six months of treatment.
Médecins Sans Frontières (MSF), or Doctors Without Borders, an international humanitarian medical organisation, welcomed the inclusion of bedaquiline in the priority list for treatment of MDR-TD
"Today, only 20 percent of people with DR-TB globally receive the treatment they need. People on standard DR-TB treatment currently have to endure an agonizing regimen of medicines for up to two years, involving as many as 20 pills per day, which can cause side effects as severe as psychosis, along with painful daily injections for up to eight months that can lead to hearing loss and deafness. The current standard DR-TB therapy typically only achieves cure rates of around 55 percent. In the past six years, two new drugs have been approved for DR-TB, but their uptake to improve TB treatment has been lagging," MSF said in a statement.
"It's well beyond overdue for people living with TB to have a better chance of getting cured of this killer disease with more effective treatments that are easier for them to tolerate," said Dr Mercedes Tatay, MSF's International Medical Secretary, currently in MSF's DR-TB project in Mumbai.
"Governments and treatment providers should not waste another minute and should urgently make sure people can access optimal treatments including bedaquiline, and this means Johnson & Johnson needs to lower the price of the drug and ensure it is available for every person who needs it," Tatay said.
In order to facilitate a scale-up, MSF has been calling for a full DR-TB treatment regimen to be priced no higher than $500.