Clostridium difficile Infection (CDI)
CDI is one of the top three most urgent antibiotic-resistant bacterial threats in the United States, according to the Centers for Disease Control. It is the leading cause of hospital-acquired infection in the United States and is responsible for the deaths of approximately 29,000 Americans each year. The incidence of first occurrence is 640,000 to 820,000 patients per year. Based on published studies, The risk of recurrence is approximately 25 percent after the primary occurrence, 40 percent after a first recurrence, and more than 60 percent for those who have experienced two or more recurrences.
The current standard of care for CDI is to treat with antibiotics. While antibiotic treatment may resolve the acute infection, it can worsen dysbiosis in individuals, potentially making patients more susceptible to a recurrence of CDI. Recurrent CDI patients receive multiple rounds of antibiotics that can worsen dysbiosis and thus make it more likely that they will relapse.
Seres Therapeutics’ development candidate SER-262 is an investigational oral microbiome therapeutic for patients with primary Clostridium difficile infection. An Ecobiotic® rationally-designed, fermented microbiome therapeutic derived by a manufacturing process that does not require human donor material, SER-262 is the first synthetically-derived and designed microbiome therapeutic ever to reach clinical-stage development. In addition, Seres’ program SER-109 continues to be evaluated in a Phase 2 study in multiply recurrent CDI.
Seres Therapeutics’ lead development candidate, SER-109, is an investigational oral microbiome therapeutic for the prevention of recurrent Clostridium difficile infection (CDI) in adults who have had three or more occurrences within a nine-month period. The FDA has designated SER-109 as a Breakthrough Therapy.
SER-109 is a patient-friendly, single-dose capsule that may repair the underlying cause of recurrent CDI—dysbiosis, which is a disrupted state of the microbiome. SER-109 was developed using computational design insights suggesting that a complex spore ecology includes keystone organisms that could address the underlying dysbiosis and return the microbiome to a healthy state. SER-109 is an ecology of bacterial spores enriched and purified from healthy, screened human donors.
The SER-262 Phase 1b study, a 24-week randomized, placebo-controlled, dose escalation study is expected to enroll approximately 60 patients who have experienced a first episode of CDI. The primary endpoint of the study will compare the CDI recurrence rate between the SER-262 and placebo groups at up to 8 weeks after dosing.