Complement Therapeutics Receives UK CTA Approval to Advance CTx001 into Opti-GAIN Phase I/II Clinical Trial in Geographic Atrophy Secondary to AMD
Complement Therapeutics GmbH (CTx), a clinical-stage biotechnology company developing next-generation therapeutics for complement-mediated diseases, today announced that it has received Clinical Trial Authorisation (CTA) approval in the United Kingdom for CTx001, the company’s investigational gene therapy programme for Geographic Atrophy (GA) secondary to age-related macular degeneration (AMD).
The CTA application for CTx001 has been approved by the Medicines and Healthcare products Regulatory Agency (MHRA). This approval builds on Complement Therapeutics’ recent U.S. Food and Drug Administration (FDA) Investigational New Drug (IND) clearance, for which the programme also holds Fast Track Designation in the United States. Together, these regulatory milestones enable acceleration of the company’s clinical development programme across sites in both the US and UK.
Dr. Rafiq Hasan, Chief Executive Officer of Complement Therapeutics, said:
UK CTA approval enables us to initiate an innovative first-in-human clinical development programme for CTx001 in Geographic Atrophy. The Opti-GAIN study has been carefully designed to leverage patients’ natural history data and incorporates novel imaging and functional endpoints to better characterise disease progression and treatment response. Together with our recent FDA IND clearance and Fast Track Designation, this positions us to evaluate CTx001 through a rigorous, multinational clinical programme across the US and UK.
CTx001 is an investigational adeno-associated virus (AAV)-based gene therapy designed to deliver a truncated version of Complement Receptor 1 (mini-CR1), enabling long-term modulation of the classical and alternative pathways of the complement cascade. Given its small size, mini-CR1 has the potential to penetrate different compartments of the eye and thereby address the inflammation associated with GA in a more robust manner. Dysregulation of the complement system is recognised as a key driver of disease progression in GA, an advanced form of dry AMD that leads to progressive and irreversible vision loss and for which treatment options remain limited.
The Opti-GAIN (Optimised Geographic Atrophy INterventional) trial is an international, first-in-human, open-label interventional Phase I/II study that leverages data from an extensive natural history programme. The clinical design of Opti-GAIN enables a detailed assessment of disease progression and treatment response using innovative endpoints, including evaluation of ellipsoid zone (EZ) attenuation and focal microperimetry. The study is therefore well placed to evaluate the safety, tolerability and preliminary efficacy of CTx001 in patients with GA secondary to AMD. The trial will enrol patients across leading retinal centres with first patient dosing expected in Q1 2026.
