Protalix BioTherapeutics recently announced that the first patient has been enrolled in the Phase 2 clinical trial evaluating the safety, efficacy and properties of its lead drug candidate, OPRX-106, for the treatment ulcerative colitis (UC), the company announced in a press release.

The proof of concept, randomized, open label Phase 2 study (NCT02768974) will evaluate the safety,  efficacy and the therapeutic properties of OPRX-106 in 20 patients with active mild to moderate ulcerative colitis, a long-term condition that causes inflammation and ulcers of the colon and rectum.

Eligible patients will be randomly assigned to either 2 mg or 8 mg oral doses of OPRX-106 once daily for eight weeks. The trial’s primary endpoint is the number of adverse events, and efficacy will be assessed with relevant disease parameters of the drug, including Mayo score and rectal bleeding. The clinical trial, currently recruiting patients, is being conducted in multiple sites across Israel.

Protalix previously concluded a Phase 1 clinical trial (NCT02107833) that evaluated the safety and drug properties of oral OPRX-106 in 15 healthy volunteers. The results, announced in August 2015, showed that OPRX-106 was safe and well-tolerated, and exhibited biological activity in the gut and activation of regulatory T cells.

Results from preclinical studies, in inflammatory bowel disease immune-mediated mouse models, showed that PRX-106 has the potential to positively affect the disease, with changes seen in symptoms and in serum levels of anti-inflammatory markers.

OPRX-106 is a plant cell-expressed recombinant human tumor necrosis factor receptor II fused to an IgG1 Fc domain (TNFRII-Fc). Administered orally, it passes through the digestive tract and the plant cells work as a natural delivery vehicle.