SER-109, also known as fecal microbiota spores, has demonstrated both efficacy and durability for
recurrent Clostridioides difficile infection.
he efficacy of SER-109 was demonstrated in ECOSPOR III, a phase 3, double-blind, placebo-controlled
trial. After 8 weeks, SER-109 recipients demonstrated a statistically significant lower incidence
of C difficile recurrence than the placebo group (12% and 40%, respectively; RR, 0.32; 95% CI, 0.18–0.58; P<0.001).
Subsequently, the ECOSPOR IV trial, a phase 3, open-label, single-arm study, focused on the safety,
efficacy, and durability of the response to SER-109 treatment in 263 adult patients. Participants
received SER-109 following the remission of symptoms after antibiotics treatment, along with
laxatives to wash out residual antibiotics from the gastrointestinal tract. The mean age was 64 and
68% of participants were female. The overall C difficile recurrence rate was 8.7% at week 8; 95% of
participants maintained this response through week 24, regardless of prior recurrences.
More than half of participants (52%) reported adverse events, most of which were mild to moderate
and gastrointestinal in nature. There were eight deaths within 8 weeks posttreatment, but none were
deemed related to the study drug.
“Recurrent C difficile infection often has a debilitating impact on patients” lives, and current
treatments are often insufficient due to the persistence of microbiome disruption,” Louis Korman,
MD, said. “Microbiome restoration, as provided by SER-109, could be a game-changer in treating this
condition.”
Source: Korman L, et al. Durability of the clinical response to SER-109, an investigational oral
microbiome therapeutic, in a phase III open-label trial (ECOSPOR IV) in patients with recurrent
Clostridioides difficile infection. Lecture 694. Presented at: DDW 2023; May 6-9, 2023; Chicago.
