Advertisement

Too few antibiotics in pipeline to tackle global drug-resistance crisis, WHO warns

Tuberculosis medication. There are 250,000 deaths a year from drug-resistant TB and only 52% of patients globally are successfully treated.
Tuberculosis medication. There are 250,000 deaths a year from drug-resistant TB and only 52% of patients globally are successfully treated. Photograph: Kevin Frayer/AP

Too few antibiotics are in the pipeline to tackle the global crisis of drug resistance, which is responsible for the rise of almost untreatable infections around the world, the World Health Organisation (WHO) warns.

Among the alarming diseases that are increasing and spreading is multi-drug resistant tuberculosis (TB), which requires treatment lasting between nine and 20 months. There are 250,000 deaths a year from drug-resistant TB and only 52% of patients globally are successfully treated. But only two new antibiotics for the disease have reached the market in 70 years.

The new WHO report, showing the paucity of new antibiotics being developed, lists 12 other pathogens that are serious dangers to health because we are running out of drugs to treat the infections they cause. Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacteriaceae that have become resistant to the carbapenem class of antibiotic are all on the critical priority list. They are what are known as gram-negative bacteria, capable of causing a range of life-threatening infections such as pneumonia, sepsis and meningitis.

Hospital infections such as C. difficile and MRSA (methicillin-resistant Staphylococcus aureus) are also of major concern. They are a particular danger to patients who are already sick and have fragile immune systems.

“Antimicrobial resistance is a global health emergency that will seriously jeopardise progress in modern medicine,” said Dr Tedros Adhanom Ghebreyesus, director-general of the WHO. “There is an urgent need for more investment in research and development for antibiotic-resistant infections including TB, otherwise we will be forced back to a time when people feared common infections and risked their lives from minor surgery.”

Ed Whiting, director of policy at the Wellcome Trust agreed and said: “There is no doubt of the urgency – the world is running out of effective antibiotics and drug-resistant infections already kill 700,000 people a year globally. We’ve made good progress in getting this on the political agenda. But now, a year on from a major UN agreement, we must see concerted action – to reinvigorate the antibiotic pipeline, ensure responsible use of existing antibiotics, and address this threat across human, animal and environmental health.”

The report’s authors have found 51 new antibiotics and biologicals currently in development that may be able to treat the diseases caused by these resistant bugs. But that will not be anywhere near enough because of the length of time it takes to get drugs approved and onto the market, and because inevitably some of the drugs will not work.

“Given the average success rates and development times in the past, the current pipeline of antibiotics and biologicals could lead to around 10 new approvals over the next five years,” says the report. “However, these new treatments will add little to the already existing arsenal and will not be sufficient to tackle the impending antimicrobial resistance threat.”

More investment is needed in basic science, drug discovery and clinical development, it says, especially for those pathogens on the WHO’s critical priority list. Gram-negative bacteria are getting less research attention because they are harder to find drugs against.

Among all these candidate medicines, only eight are classed by the WHO as innovative treatments that will add value to the current antibiotic treatment arsenal. The rest are just modifications of drugs that already exist and may already be compromised.

“Pharmaceutical companies and researchers must urgently focus on new antibiotics against certain types of extremely serious infections that can kill patients in a matter of days because we have no line of defence,” says Dr Suzanne Hill, director of the department of essential medicines at the WHO which produced the report.

There is serious concern over the spread of first multi-drug-resistant TB and then extremely drug-resistant TB worldwide. Drug-resistant TB has been found all over the globe.
“Research for tuberculosis is seriously underfunded,” said Dr Mario Raviglione, director of the WHO Global TB Programme. “If we are to end TB, more than $800m per year is urgently needed to fund research.”

But new drugs will not be enough, says the WHO. Unless they are sparingly used, resistance will build to the new drugs as well. The WHO says it is working with countries and partners to improve infection prevention and control and to foster appropriate use of existing and future antibiotics. It is also developing guidance for the responsible use of antibiotics in the human, animal and agricultural sectors.