Diet – an unconsidered factor in designing clinical trials of microbiome therapeutics

Abstract

Clinical trials in the microbiome space should take the patients’ diet into account, either as inclusion/exclusion criteria or as monitoring of diet-related biomarkers. Such a design would ideally inform how much of the clinical effect is diet-related and how much is drug-related, thereby allowing for something akin to a ‘diet normalized’ drug efficacy readout. The ‘placebo’ in microbiome modulating drugs is not another tablet or capsule containing pharmaceutical excipients – it is the diet.