The US Food and Drug Administration (FDA) has released a draft guidance for drug development and clinical trials for diabetic foot infections (DFIs).
The agency states the purpose of the guidance is to "assist sponsors in the clinical development of drugs for the treatment of DFIs without concomitant bone and joint involvement".
DFIs are soft tissue or bone infections that are often associated with neuropathy or peripheral arterial disease in diabetic patients.
In the document, the FDA states that guidance for "Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for Treatment" does not address DFI, resulting in the need for separate guidance.
Sponsors should take important considerations in the development of drugs to include the types of bacteria that are commonly associated with DFI, which can be either monomicrobial or polymicrobial.
The guidance was released on 16 October 2023 and written comments should be submitted to the agency by 18 December 2023.
Contents of the draft guidance
The guidance provides sponsors with instruction for trial design, entry criteria and efficacy endpoints.
In Phase I, sponsors should ensure the candidate demonstrates adequate penetration into the outer skin layers.
In Phase III, the guidance states trials should be active-controlled, prospective, randomised, and double-blinded using noninferiority (NI) or 128 superiority trial design.
The primary endpoint at Phase III should be the resolution or improvement of all signs and symptoms of DFI to the extent that no further antibacterial drug therapy is needed as long as the patient has not been in receipt of rescue therapy, unplanned surgical debridement, amputation, or death.
Subjects enrolled should have type I or II diabetes mellitus with a foot infection that started at or below the malleoli and does not extend above the knee, without concomitant osteomyelitis and infectious arthritis.
Subjects should have moderate to severe DFIs, including patients who may have vascular insufficiency and neuropathy and who are representative of the population in which antibacterial drug treatment is recommended.
To define the scale of infection, sponsors are recommended to use the International Working Group on the Diabetic Foot (IWGDF) DFI criteria.
