A secondary analysis of results from a phase 3 clinical trial found that an investigational microbiome therapeutic for treatment of recurrent Clostridioides difficile infection (rCDI) was associated with significant quality-of-life improvements compared with placebo, researchers reported this week in JAMA Network Open.
The analysis looked at data from the randomized, double-blind ECOSPOR III trial, which randomized adults with rCDI to receive four daily doses of SER-109—a therapeutic composed of Firmicutes bacterial spores—or a placebo for 3 days. Previously published results from the trial have shown that SER-109, which was developed by Seres Therapeutics, was superior to placebo for treatment of rCDI 8 weeks after dosing and well-tolerated.
For this study, researchers looked at scores on the Clostridioides difficile Quality of Life Survey (Cdiff32), a disease-specific, health-related quality-of-life (HRQOL) survey completed by 182 trial participants (89 in the SER-109 group and 93 in the placebo group) at baseline, week 1, and week 8.
Scores were similar between patients in the SER-109 and placebo groups at baseline (52.0 vs 52.8, respectively). But the proportion of patients with improved HRQOL outcomes from baseline in the total Cdiff32 score and physical domain and subdomain scores was significantly higher in the SER-109 group than the placebo group at week 1 (49.4% vs 26.9%) and week 8 (66.3% vs 48.4%).
Among patients in the placebo group, improvements in HRQOL were primarily observed in patients with nonrecurrent CDI, while patients in the SER-109 group reported improvements in HRQOL regardless of clinical outcome.
The study authors also note that patients in the SER-109 group showed greater improvement in the mental domain and subdomain scores, which may suggest the potential role of the microbiome in mood-related disorders related to the gut-brain axis.
"These data suggest that an investigational microbiome therapeutic not only offers the clinical benefits of reduced CDI recurrence, but may also improve HRQOL, an important patient-reported outcome of great interest to patients, clinicians, payers, and regulators," they wrote.