Why don’t we have more new antibiotics?

Buried in all this  recent measles media was an announcement of a newly discovered antibiotic, teixobactin, that its discoverers, Kim Lewis and his Northeastern University in Boston colleague Slava Epstein, think could work without allowing the development of antibiotic resistance. This is the first new antibiotic discovered in nearly 30 years. Tests showed that the newly discovered teixobactin outperformed vancomycin (a drug frequently used to treat MRSA) by a factor of 100 in petri dishes. It’s expected that resistance to teixobactin won’t happen because teixobactin acts on two different targets that are highly conserved among many bacterial species and aren’t easily changed.

Lewis and Epstein have been working to isolate new antibiotics from soil for years. The reason for looking for new antibiotics in soil is because soil is teeming with bacteria and those bacteria engage in a type of chemical warfare by releasing compounds to kill other competing bacteria. It is those compounds that Lewis and his team are looking to isolate and develop into new antibiotics. The problem with isolating bacteria from soil samples has been that many of those bacteria do not like to live in the laboratory, making it hard to study them and isolate their chemical warfare compounds. In 2002, Lewis and Epstein managed to develop a technique allowing them to coax the soil bacteria into growing more readily in a petri dish.

The need for new antibiotics, not just updates to those familiar ones we’ve been tinkering with for ages, is a huge problem for the world. Many bacteria have developed resistance to the first generation antibiotics, such as penicillin, and many more have started to develop resistance to later generations of antibiotics, such as methicillin. The WHO states that antimicrobial resistance is a serious threat to the world with the capability to to affect anyone of any age in any country.

Pharmaceutical companies have been getting out of the antibiotic development arena for a couple of different reasons. Developing antibiotics costs time and money, things which companies need to recoup in the cost of the drug, but people only take antibiotics for a short time. On average, pharmaceutical companies spend $5 billion on R&D to bring a new drug to market. Which means antibiotics are not as lucrative to invest in as drugs for chronic conditions that people take for years on end. The US Congress has noticed the need to entice companies into R&D of antibiotics and has passed legislation meant to fast-track the process and help companies recoup financial costs of R&D. However as large companies have slowly left the market, small companies, like the NovoBiotec Pharmaceuticals formed to commercialize Lewis and Epstein’s approach, ended up with a large share in the R&D of antibiotics. Research hospitals and universities are also getting into the game. Researchers at St. Jude Children’s Research Hospital developed a new class of antibiotics to target drug-resistant TB.

Even as more players enter back into the antibiotic development game, the bacteria continue to evolve resistance. The discovery of teixobactin, as one of a new class of drugs, is a promising start to the problem of antibiotic resistance but continued investment is needed into discovering new antibiotics as the disease-causing bacteria are not going to go quietly.

What else do you think we can do to address antibiotic resistance? Will we just have to stay one step ahead of the bacteria for all eternity?

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