CDC seeks new weapons against antimicrobial resistance

When it comes to antimicrobial resistance, the pharmaceutical industry could ride to the rescue, just as it did in the private-public partnership that produced the COVID-19 vaccines that saved millions of lives.

Michael Craig, who oversees cross-cutting antibiotic resistance activities for the Centers for Disease Control and Prevention (CDC), said discussions about the drug industry and antimicrobial resistance often focus on the development of new antibiotics, but that’s usually where the conversation ends because there’s no profit in it.

“When a new drug, a blockbuster, comes on the market, we want to use it,” Craig told Fierce Healthcare. “Because we know that it has benefit over and above what had previously been on the market. Whereas, with antibiotics or antifungals, the opposite is usually true. The real tension with antibiotics or antifungals is we don’t want to use them the same way we use other drugs.”

Providers, health plans and the Department of Health and Human Services would prefer to save the new blockbuster antibiotic for when it’s really needed: when all the other antibiotics prove ineffective.

“Because if we choose to use the blockbuster first, then we’re only going to accelerate the resistance and the problems we have with that,” Craig said.

Michael Craig of CDC
Michael Craig (Centers for Disease Control and Prevention)

Drug manufacturers would have to spend millions of dollars on research and development for a medication whose primary purpose would be to be used only when all else fails.

One possible answer, according to Craig, would be the development of decolonization agents, something that was discussed at a joint virtual workshop hosted by the CDC and the Food and Drug Administration (FDA) last August.

Decolonization involves killing or neutralizing pathogens that already exist in the microbiome of individuals. For instance, says Craig, many more people carry Candida auris on their skin and GI tract without knowing if they are infected. 

“The bacteria and fungi that we’re talking about, that are most challenging and most resistant, can live in our bodies without causing infection,” Craig said. “They’re often in our guts, but they can live in our lungs, they can live in our repository system, or on our skin. And in that situation, where they’re colonizing a person but not infecting them, they are leading to transmission. That germ can then spread to the healthcare environment, especially if they’re a patient in a nursing home or in a hospital, and they can contaminate that environment. They can also spread person to person.”

The pathogens that have garnered headlines recently come from the viral, bacterial and fungi families and include Candida auris, H5N1, Marburg, blastomycosis and Shigella, but there are more.

“In our threats report, we’re talking about 18 different antimicrobial resistant pathogens that all have some degree of resistance to different antibiotics or antifungals that are used to treat them,” Craig said. (He notes that not every pathogen listed above is on the threats report.)

Decolonization had been somewhat in vogue about a decade ago and resurfaces as a topic occasionally, but for the most part it doesn’t get much attention.

Richard Stefanacci of Jefferson College of Population Health at Thomas Jefferson University, noted in an email to Fierce Healthcare that “it’s been years and has failed to gain traction. The one form that we did use was Bactroban to nasal regions to stop the spreading of MRSA.”

The CDC’s earlier explorations sprung from fieldwork at the agency’s epicenters about processes more in the domain of mitigation—similar, or the same, to ones used in the COVID-19 pandemic, such as masking or social distancing. The epicenters also found antimicrobial uses for chlorhexidine, a local antiseptic, and mupirocin, used to treat impetigo as well as other skin infections caused by bacteria.

“That’s what I call decolonization 1.0,” said Craig. “The next potential areas are other agents that can decolonize the gut or other body sites more effectively.”

Pharmaceutical companies would have the incentive to create medications for which there already exists a large market, but that might not be enough.

“We’ve talked to the FDA about this, because there’s no clear regulatory pathway for getting a decolonization agent to market,” Craig said.

A “variety of companies” are in the process of developing decolonization agents, said Craig, adding that such medication could be “a game-changer.”

Stefanacci said the “key here is clear guidance from the CDC on appropriate use. This will be a challenge as the CDC has lost credibility through COVID, so recapturing that will take time. In addition, we’ll need payers to buy in and provide coverage. And finally, this will also need health systems to accept this significant process change. A lot needs to happen.”

Kevin Kavanagh, M.D., founder and president of the patient advocacy organization Health Watch USA, applauds the CDC for investigating decolonization in more depth.

“This new CDC strategy could represent a paradigm shift in how we approach the prevention of infectious diseases,” Kavanagh told Fierce Healthcare in an email. “Identifying carriers along with isolation and decolonization is key to the control of many pathogens. This includes MRSA, Candida auris and even COVID-19. In actuality, we should determine all the bacteria which are present in a patient’s microbiome, both on admission to healthcare facilities and nursing homes but also as part of a physical examination.”

The identification of individuals carrying dangerous pathogens would be a good first step, said Kavanagh.

“If decolonization fails, sequestering the patient or nursing home resident with others with compatible microbiomes may be an option,” Kavanagh said. “However, staff should continue contact precautions, so they do not become colonized and spread the pathogens to the community and their home.”

Craig said he also believes in the “ounce of prevention” approach when it comes to warding off pathogens. He noted that the progress that had been made before the pandemic in this area had a lot to do with improvements in infection control practices in hospitals and other healthcare settings.

But Craig said he worries that the big picture sometimes gets lost when the focus turns toward one pathogen that happens to be making headlines at a particular time. 

“What we’re trying to do, and get greater attention to, is that it’s not just one pathogen that we need to be concerned with,” he said.