Pfizer (NYSE:PFE) is trading lower in the pre-market Tuesday after the company announced that its pivotal Phase 3 study for Clostridioides difficile vaccine candidate (PF-06425090) did not meet the primary endpoint in the prevention of the infection.
However, in terms of secondary endpoints, the experimental vaccine has demonstrated its potential in reducing the duration and severity of the disease, Pfizer (PFE) said, adding that the company is currently evaluating the next steps of the program.
The vaccine was found to be well tolerated with a favorable safety profile in the CLOVER trial that involved nearly 17,500 adults aged 50 years and older.
The subjects received three doses of the C. difficile vaccine (n=8,766) or placebo (n=8,769) at 0, 1, and 6 months.
In terms of people who sought medical attention for CDI, the case split between the vaccine and placebo stood at 0-11, indicating 100% vaccine efficacy.
The median and mean CDI duration for vaccine and placebo reached 1 versus 4 days and 3 versus 16 days, implying a 75% and 80% reduction in disease episode, respectively in vaccinated people.
“We are encouraged by the promising potential benefit observed against more severe C. difficile infection, as a large portion of cases lead to extended diarrhea episodes that can require hospitalization,” noted Kathrin Jansen, Senior Vice President and Head of Vaccine Research & Development of Pfizer (PFE).
Clostridioides difficile infection is a potentially fatal condition linked to diarrhea.