Researchers behind a large trial of antibiotics for chronic lung diseases have found that that the drugs are ineffective in preventing hospitalization or death among those with life-threatening idiopathic pulmonary fibrosis.
Idiopathic pulmonary fibrosis is a condition in which scar tissue builds up in the lungs over time, gradually preventing them from being able to supply oxygen to the body. The condition typically affects men over the age of 50. After diagnosis, patients survive for an average of 2-5 years.
So far, doctors are uncertain as to what causes it. Environmental and genetic factors, as well as lung infections, are thought to play a part. However, as studies highlighting the effects of microorganisms on general health have been increasing, the researchers suspected that they may play a role here too.
Theoretically, they thought, an imbalance of microorganisms in the lungs may have caused the illness. As such, they suspected antimicrobials may have been able to resolve the condition. This came especially after successful trials of antimicrobials in mice.
For the clinical trial, the researchers recruited 513 patients aged 40 or over with idiopathic pulmonary fibrosis from 35 sites. While half received antimicrobial drugs- either co-trimoxazole or doxycycline, the others received standard care.
At a median follow-up of 12.7 months, the researchers found that those treated with antimicrobials showed no difference in outcomes to those treated with standard care. Both breathing-related hospitalization and death rates remained the same between the groups.
"As the largest single study in IPF [idiopathic pulmonary fibrosis] ever conducted, I think we are going to learn a lot as we look at things more closely.” says Imre Noth, one of the study's authors.
“Might our choice of antibiotics have been the right ones? Were there some patients that did better than others? Who should we be targeting for treatment? All things this study will help in the future. I am heartened and hopeful moving forward as this study teaches us a lot for the next one, and each study gets us closer to better treatments and a cure."
While the researchers are disappointed that antimicrobials proved ineffective against the condition, they say that the new research will go some way to prevent unnecessary antibiotic use that could contribute to antibiotic resistance. The trial, the largest for idiopathic pulmonary fibrosis ever conducted, was also helpful in collecting biological samples that may be used in future research.