US-based Synthetic Biologics has started a Phase IIa trial of its investigational oral beta-lactamase enzyme, SYN-004, which is designed to protect the microbiome and prevent C. difficile infection (CDI).

The randomised, multi-centre, open-label trial is designed to evaluate the gastrointestinal (GI) antibiotic-degrading effects and the safety of SYN-004 and participants will be enrolled at up to four trial sites located in the US and Canada.

During the trial, ability of two different dose strengths of SYN-004 will be evaluated to degrade residual IV ceftriaxone in the GI tract of up to 20 healthy participants with functioning ileostomies, without affecting the concentrations of IV ceftriaxone in the bloodstream.

"We are excited to start our Phase IIa trial of SYN-004 on schedule."

The trial includes two treatment phases for all participants: the administration of IV ceftriaxone alone, and the administration of one of two doses of oral SYN-004 and IV ceftriaxone.

In order to measure the ability of SYN-004 to degrade the residual antibiotic, chyme samples will be collected from the participants.

C. difficile is frequently associated with intravenous (IV) antibiotic treatment.

Synthetic Biologics chief executive officer Jeffrey Riley said: "We are excited to start our Phase IIa trial of SYN-004 on schedule.

"Synthetic Biologics believes SYN-004 holds the potential to protect the microbiome from the damaging effects of antibiotics and dramatically reduce C. difficile infections through prevention vs. treatment.

"We anticipate reporting topline results from this Phase IIa clinical trial during the second quarter of 2015, and initiating the Phase IIb clinical trial in the second half of this year."

C. difficile is frequently associated with intravenous (IV) antibiotic treatment and it has been categorised as an ‘urgent public health threat’ by the US Centers for Disease Control and Prevention (CDC).

CDC has also stated the need for research to better understand the role of normal gut bacteria.

SYN-004 is designed to block the unintended harmful effects of antibiotics within the GI tract and maintain the natural balance of the gut microbiome.