Access, watch, reserve: WHO committee advises when to use common antibiotics
For the first time in its 40-year history, WHO’s Model List of Essential Medicines includes advice on when and when not to use certain antibiotics — a significant change that health officials said was aimed at containing the global threat of antimicrobial resistance, optimizing treatment and preserving last-resort antibiotics.
Eighteen WHO committee members and advisors grouped 39 essential antibiotics into three groups called “access,” “watch” and “reserve” and made recommendations on when medicines in each group should be used.
Initially, the categories apply only to antibiotics used to treat 21 of the most common infections, WHO said. But the recommendations could be broadened in the future to include more drugs.
“From an antimicrobial resistance perspective, this is really a very important day,” Marc Sprenger, MD, PhD, director of WHO’s secretariat for antimicrobial resistance, said during a teleconference.
The essential medicines list, which is updated every 2 years, is fundamentally an international blueprint laying out medicines that should always be available in health systems around the globe, according to Marie-Paule Kieny, PhD, WHO assistant director-general of health systems and innovation. Medicines are chosen based on safety, efficacy and public health relevance, and many countries use it to create their own lists at a national level, which, among other things, can increase access to the drugs and provide the basis for reimbursement lists for health insurance.
In addition to revising the section on antibiotics, WHO experts added 55 medicines — 30 for adults and 25 for children — including 22 antibiotics, and specified new uses for nine drugs that had been included in past lists. The experts met at WHO headquarters in Geneva, Switzerland, in March. Drugs for hepatitis C virus, HIV, tuberculosis and cancer were added to the list, bringing the total to 433.
“Essential medicines should be available in health systems everywhere at all times,” Kieny said.
Medicines added to the list this year include Epclusa (sofosbuvir/velpatasvir, Gilead Sciences), the once-daily tablet treating all six major forms of HCV; Tivicay (dolutegravir, ViiV Healthcare) for HIV infection; pre-exposure prophylaxis (PrEP) with tenofovir alone or in combination with emtricitabine or lamivudine to prevent HIV infection; multidrug-resistant TB medicines Deltyba (delamanid, Otsuka) for children and adolescents and Lamprene (clofazimine, Novartis) for children and adults; and child-friendly fixed-dose combination formulations of ethambutol, isoniazid, pyrazinamide and rifampicin for treating pediatric TB.
The list now includes oral cancer medicines Sprycel (dasatinib, Bristol-Myers Squibb) and Tasigna (nilotinib, Novartis) for chronic myeloid leukemia resistant to standard treatment; and fentanyl skin patches and methadone for pain relief in cancer patients.
“I would like to stress that currently many of these medicines are sold at very high prices and may be unaffordable for health systems irrespective of the country,” Suzanne Hill, BMed, PhD, WHO director for essential medicines and health products, said. “The fact that they are now included on the essential medicines list sends a strong message to all public health actors that these medicines provide true public health benefits and really should be made available when needed. But obviously, for health systems to do this, the price must be affordable.”
Antibiotics listed under the “access” group — the largest of the three categories — include drugs like amoxicillin with lower resistance potential that should be available at all times. The “watch” group contains first- or second-choice drugs like ciprofloxacin that have a higher potential for resistance and should be used sparingly, according to the group.
Drugs in the “reserve” list include last-resort antibiotics like colistin, Zyvox (linezolid, Pfizer) and new-generation cephalosporins used to treat life-threatening infections due to multidrug-resistant bacteria.
“These medicines should be protected and prioritized as key targets in stewardship programs to preserve their effectiveness,” Kieny said.
It is the first time the list has specified when and when not to use certain antibiotics, according to Kieny, who said she does not expect the change to be a “quick-fix solution” to antimicrobial resistance. Previous efforts to address antibiotic resistance have mostly been aimed at changing the behavior of prescribers, yielding modest results, Kieny said.
“We hope that this new categorization of antibiotics — emerging at a time when political awareness of the issue is high — will increase countries’ commitment to address the problem in targeted ways,” she said. “We think the political will is there, but this needs to be followed by strong policies.” – by Gerard Gallagher
WHO. Technical report series – The selection and use of essential medicines. 2017. http://www.who.int/medicines/publications/essentialmedicines/EML_2017_EC21_Unedited_Full_Report.pdf?ua=1. Accessed June 6, 2017.
Disclosure: Hill, Kieny and Sprenger report no relevant financial disclosures.