CANbridge Pharmaceuticals, Inc. (1228.HK), a global biopharmaceutical company, with a foundation in China, committed to the research, development and commercialization of transformative therapies to treat rare diseases and oncology, announced positive preliminary results from the ongoing Phase 1b study of omoprubart (CAN106), a novel, long-acting, anti-C5 complement recombinant humanized monoclonal antibody, in paroxysmal nocturnal hemoglobinuria (PNH) in China. In this 26-week, multicenter, open-label, dose ascending trial in 16 PNH patients who have not received complement-inhibitor treatment, omoprubart was administered intravenously every four weeks at three different maintenance doses (20 mg/kg, n=4; 40 mg/kg, n=4, and 80 mg/kg, n=8) after a loading dose period. The goals of the study are to assess safety, pharmacokinetics, pharmacodynamics and efficacy in subjects with PNH.
Data from the two lower dose cohorts was reviewed through 26 weeks, while data from the highest dose cohort was reviewed through 13 weeks, the latest timepoint. Omoprubart treatment resulted in rapid, dose-dependent reductions in LDH from baseline, with mean LDH reductions of 49% in Cohort 1, 73% in Cohort 2, and 81% in Cohort 3. LDH is a serum biomarker that indicates the level of hemolysis (blood cell destruction). The percentage of subjects reaching an LDH level of less than 1.5 times the upper limit of normal, the therapeutic goal for hemolysis inhibition with an anti-C5 antibody, at least once during the study, was 25% in Cohort 1, 50% in Cohort 2, and 88% in Cohort 3. Hemoglobin levels increased across all study cohorts, with mean increases from baseline of approximately 2 g/dL in Cohorts 1 and 2 at Week 26, and 1 g/dL in Cohort 3 at Week 13. All subjects in Cohort 1 have been treated with omoprubart for over one year, with a mean hemoglobin increase of approximately 4 g/dL from baseline. Patients with PNH often require frequent blood transfusions to treat severe anemia due to hemolysis.
Omoprubart showed dose-proportional exposure. Free C5 levels were rapidly reduced within 24 hours in a dose-dependent manner, with all subjects in Cohort 3 maintaining values below 0.5 μg/mL, a benchmark for complete C5 inhibition.
Omoprubart was safe and well-tolerated at all doses. All drug-related adverse events were mild or moderate and transient, and none led to discontinuation from the study. There were no drug-related serious adverse events, and no cases of anaphylaxis or meningococcal infection.
CANbridge plans to advance Omoprubart to a pivotal trial in PNH in China, where there are no approved long-acting PNH treatments. CANbridge holds exclusive global development and commercialization rights to omoprubart for all indications. It is currently in development for PNH, as well as for other complement-mediated diseases that involve activation of the C5 protein.
CANbridge will hold an investor call to discuss these results. The Chinese-language call will be on Monday, June 26, 11:00 AM Beijing Time. To attend, please go to: https://us02web.zoom.us/webinar/register/WN_wRa8LptzREOVHa-HJQHeQA#/registration.
The English language call will be on Tuesday, June 27, 10:00 AM EDT. To attend, please go to: https://us02web.zoom.us/webinar/register/WN_MZ2Wo8xwSLe5q7mVKngJLw#/registration.
“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, Ph.D., founder, chairman and CEO of CANbridge Pharmaceuticals Inc. “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. Based on the strength of these data, we plan to advance omoprubart to a pivotal trial in PNH in China and will meet shortly with the CDE to discuss our next steps. We look forward to further developing this first potentially long-acting PNH treatment in China, where patients do not have ready market access to anti-C5 antibody treatment.”
About Omoprubart (CAN106)
Omoprubart (CAN106) is a novel, long-acting recombinant humanized monoclonal antibody that binds to and neutralizes C5, a key component of the complement system. By preventing the cleavage of C5 into C5a and C5b, omoprubart is intended to prevent the C5b-dependent formation and activation of the membrane attack complex (MAC) on susceptible cell surfaces, which results in cell lysis (destruction). In the case of paroxysmal nocturnal hemoglobinuria (PNH), this is hemolysis, or the destruction of red blood cells. Omoprubart acts downstream of C3 in the complement pathway, preserving the generation of C3a and C3b, which are important for innate immunity.
Omoprubart has demonstrated a favorable PK/PD profile, safety and tolerability, as well as complete blockade of the complement system in healthy subjects in a Phase 1a study, indicating thatomoprubart has the potential to effectively inhibit C5 in patients with certain complement-mediated diseases. Data from the omoprubart Phase 1a study, indicating rapid, potent and sustained complement blockade with a single dose in healthy subjects, was presented at the European Hematology Association Congress in Vienna, Austria; the National Conference on Hematology, in Shanghai, China, and the Annual Complement Based Drug Development Summit, in Boston, MA USA in 2022.
CANbridge holds exclusive global development and commercialization rights to omoprubart for all indications. It is currently in development for PNH, as well as for other complement-mediated diseases that involve activation of the C5 protein.
About Paroxysmal Nocturnal Hemoglobinuria (PNH)
Paroxysmal nocturnal hemoglobinuria (PNH) belongs to a group of fatal and rare disorders that occur when the complement system, a part of the immune system that helps clear microbes and damaged cells by attacking their cell membranes, is dysregulated. In patients with PNH, the proteins that normally protect their red blood cells are not present, leaving these denuded cells susceptible to complement attack, which results in their destruction (hemolysis). This leads to severe anemia, thromboembolism, gastrointestinal pain and dysfunction, fatigue, cardiac failure, pulmonary hypertension, renal impairment, and eventually, death. Treatment options include steroids, allogeneic bone marrow transplantation, the anti-C5 monoclonal antibodies eculizumab and ravulizumab, and the C3 inhibitor, pegcetacoplan. PNH is an acquired genetic condition that can occur at any age across genders and race, but most commonly presents in adults in their 30s to 40s and continues for the life of the patient.
The incidence of PNH in Western countries is estimated to be 1-to-2 per million people per year. In Asia, the rate is approximately 10 per million people per year, according to the 2019 China Rare Diseases Diagnosis and Treatment Guide.
Source: https://www.businesswire.com/