Zimura® Anti-C5 Clinical Development
Ophthotech has completed a multicenter, ascending-dose, parallel-group, open-label Phase 2a clinical trial evaluating the safety and tolerability of Zimura® administered in combination with an anti-VEGF drug for the treatment of wet AMD. Zimura® was generally well tolerated in this trial when tested in combination with anti-VEGF treatment.
In a subgroup of 43 patients who had not previously been treated with anti-VEGF therapy and who received six injections of Zimura® in combination with anti-VEGF treatment, there was a mean increase in visual acuity from baseline at all timepoints. At a follow-up visit at week 24 of the trial, there was an improvement in mean visual acuity from baseline of 13.6 letters for patients receiving 0.3 mg, 11.7 letters for those treated with 1.0 mg, and 15.3 letters for patients receiving 2.0 mg of Zimura®.
Based on results of our Phase 2a trial, data from a third-party clinical trial and multiple published studies suggesting that the complement pathway plays a significant role in dry AMD, we plan to initiate a Phase 2/3 clinical trial investigating Zimura® for treatment of geographic atrophy, a severe form of dry AMD affecting approximately 8 million patients worldwide.
How Zimura® Works
Based on preclinical and pharmacogenetic studies, there is evidence that development of AMD involves a complement-mediated inflammatory component. Zimura® is a chemically synthesized aptamer that inhibits complement factor C5, a central component of the complement cascade believed to be involved in the development of AMD. The complement pathway is part of the innate immune system and is a complex system of proteins that interact in a cascade. Independent studies have implicated local inflammation and activation of the complement cascade in drusen formation, a hallmark of dry AMD that can be a precursor to the development of wet AMD.