Novel Antibiotics May Be Noninferior but Are They Becoming Less Effective?: a Systematic Review.

Novel antibiotics approved by noninferiority trials may become less effective over time in two scenarios: (i) the treatment effect in studies of novel antibiotics may be consistently worse than studies of older antibiotics; (ii) when a decreasingly effective control arm is used in a series of noninferiority trials. Our systematic review of 175 noninferiority antibiotic trials found these scenarios to be rare.