A new antibiotic combo has proven promising in a clinical trial for treating an often-deadly form of pneumonia. The experimental drug was found to be at least as effective in preventing death as the current standard, but with far milder side effects.
The more exposure bacteria get to a specific antibiotic, the better they evolve defenses against it, and eventually that drug is no longer effective. Traditionally when this happens we just move onto new drugs, but the supply is rapidly running out. In many cases we’re down to our last resort options, and even those are starting to fail in large numbers. If we don’t get new defenses out soon, we could be headed for a new “dark age of medicine” where even basic infections become lethal once again.
Now there’s some new hope out of a clinical trial led by researchers at Rutgers. The trial investigated a strain of pneumonia known as carbapenem-resistant Acinetobacter baumannii–calcoaceticus (ABC) complex, which is usually picked up by patients in hospital for other reasons and is often fatal. The A. baumannii species currently tops WHO’s list of priority pathogens.
In the trial, 181 patients with confirmed ABC infections were given a drug combo of imipenem-cilastatin, then followed up with either the best current treatment – colistin – or the experimental drug duo of sulbactam-durlobactam. After 28 days, the mortality rates (from multiple causes) was compared between the two groups.
In the sulbactam–durlobactam group, mortality was 12 of 63 patients, or 19%. Of those receiving colistin, mortality reached 20 out of 62, or 32%. These results suggest that the new drug is at least as effective as colistin in preventing fatalities from ABC infections, but there isn’t yet enough data to prove that it’s superior in real world settings.
One area where it has been confirmed to be better is in its side effects. Colistin is known for its unpleasant adverse effects, with serious cases leading to kidney injuries. But sulbactam–durlobactam was found to induce significantly less severe side effects.
The new treatment was also simpler to administer. Colistin doses depend on the weight of the patient, but sulbactam–durlobactam can be given at the same dosage to anybody, reducing the chance of errors.
Currently, durlobactam hasn’t been approved for use by the FDA, but based on these trial results the administration’s Antimicrobial Drugs Advisory Committee has recommended that this combo be approved for treating ABC. If that happens, it could be here sooner than we might think.
“If all moves quickly, infected patients could begin receiving sulbactam-durlobactam as part of normal clinical care the second half of this year,” said Keith Kaye, first author of the study. “Unfortunately, sulbactam-durlobactam isn’t the sort of wide-spectrum antibiotic that could prove effective in treating a wide variety of antibiotic-resistant infections, but it’s very good at treating this particularly dangerous one, and that’s a significant win.”
The trial results were published in The Lancet Infectious Diseases.
Source: Rutgers