Preliminary results from the ongoing phase 1b study evaluating omoprubart (CAN106) for the treatment of paroxysmal nocturnal hemoglobinuria (PNH) suggest high efficacy and safety, CANbridge Pharmaceuticals announced.

The biopharmaceutical company plans to proceed with a pivotal trial of omoprubart in China, as no long-acting PNH treatments are approved there.

“These strong phase 1b preliminary results, showing comparable efficacy and safety, to date, to the only approved PNH anti-C5 antibody therapy in China, at half the dosing frequency, provide proof-of-concept for the use of omoprubart in additional indications, as complement blockade in PNH is a bellwether for other complement-mediated diseases,“ said James Xue, PhD, founder, chairman, and CEO of CANbridge Pharmaceuticals, Inc.

This 26-week, multicenter, open-label, dose-ascending trial enrolled 16 patients with PNH with the goal of assessing the safety, pharmacokinetics, pharmacodynamics, and efficacy of the experimental medication.

Read more about PNH experimental therapies

The participants received omoprubart intravenously every 4 weeks at 3 different maintenance doses (20 mg/kg, n=4; 40 mg/kg, n=4, and 80 mg/kg, n=8) after a loading dose period.

According to the preliminary data, the experimental medication caused rapid, dose-dependent reductions in lactate dehydrogenase and an increase in hemoglobin concentrations compared with baseline. The free C5 levels were also rapidly reduced within 24 hours.

“We are particularly encouraged by the increased hemoglobin levels seen in the trial, which could decrease or eliminate blood transfusions, often used chronically in PNH patients, and reduce the burden on the healthcare system, ” Xue added.  

Read more about PNH treatment

The experimental drug was safe and well-tolerated at all doses, causing only mild and moderate drug-related adverse events. There were no reports of anaphylaxis or meningococcal infection, and no participants had to discontinue from the study.

Omoprubart is a novel, long-acting recombinant humanized monoclonal antibody that binds to C5 while preserving the generation of C3a and C3b. The experimental medication holds potential for PNH as well as other complement-mediated diseases that involve activation of the C5 protein.


CANbridge reports positive preliminary data in the omoprubart (CAN106) phase 1b trial in paroxysmal nocturnal hemoglobinuria (PNH) in China. News release. CANbridge Pharmaceuticals, Inc.; June 26, 2023.