The US Food and Drug Administration (FDA) on Friday finalized guidance intended to help drugmakers prepare the data necessary to support the approval of new antibacterial drugs.
Antimicrobial resistance (AMR) is increasingly being recognized as a global threat to public health, with the World Health Organization (WHO) calling AMR "so serious that it threatens the achievements of modern healthcare."
The threat is compounded by the fact that while bacteria are becoming increasingly resistant to existing drugs, the pipeline for new antibiotics has slowed considerably, and in the past 30 years, scientists have only discovered a single new class of antibiotics.
In June, Center for Drug Evaluation and Research Director Janet Woodcock said the antibiotics pipeline is "fragile and weak," and called for new incentives to help spur the development of such drugs.
Specifically, FDA says the guidance is intended to help sponsors assemble the "overall microbiology development program needed to support clinical development and approval of antibacterial drugs administered systemically as well as microbiology information collected after approval."
During early nonclinical development, FDA says sponsors should evaluate their drug candidates to determine their spectrum of activity against a range of bacteria, define the drug's mechanism of action, measure the ability of a drug to penetrate host cells and characterize any resistance mechanisms found in the target bacteria.
FDA says that sponsors should also compare their candidates against already approved antibacterial drugs when evaluating both the candidates' spectrum of activity and resistance profile.
However, FDA says it recognizes that assembling detailed information about a new type of antibacterial's mechanism of action, resistance or cross-resistance may not be feasible at the time a sponsor submits an investigational new drug application (IND) to the agency. As such, FDA says it expects this information early, "ideally before initiation of phase 2 clinical development."
Notably, the guidance retains a provision from the draft guidance allowing sponsors to label their products with a "first" and "second" list of bacteria, with bacteria the drug is indicated to target appearing on the first list. According to FDA, "The second list is based on the relevance of the bacteria to the indication and its susceptibility to concentrations of the antibacterial drug that can be achieved using the proposed dosage … The inclusion of bacteria in the second list is not based on results from adequate and well-controlled clinical trials."
The guidance goes on to make a number of recommendations for sponsors on generating and interpreting susceptibility data, studying fixed dose combination antibiotics and studying antibiotics in animal models.