On August 25, 2026, the initiation meeting for the "Single-Center, Randomized, Single-Blind, Placebo-Controlled, Single-Dose, Dose-Escalation Phase I Clinical Trial to Evaluate the Safety, Tolerability, and Pharmacokinetics of GC801 Injection in Healthy Participants" was held at Beijing Luhe Hospital, Capital Medical University. Professor Wang Xuhong, Principal Investigator of the study site, together with core members of the research team, members of the Clinical Trial Institution office, and the responsible personnel from the sponsor's clinical operations and clinical development departments, attended the meeting.
The trial has been approved by the NMPA and the Ethics Committee of Beijing Luhe Hospital, Capital Medical University. This study aims to evaluate the safety, tolerability, and pharmacokinetic profile of GC801 Injection following single-dose administration in healthy participants, and plans to enroll 40 healthy subjects. This Phase I clinical trial will accumulate preliminary clinical experience with GC801 in humans and provide a basis for the subsequent Phase II patient study.
At the initiation meeting, Genecradle Therapeutics delivered a systematic introduction to the trial protocol and study procedures, and walked through key documents one by one, including clinical trial project management, the Investigational Medicinal Product manual, and the sample handling manual. In response to the safety considerations of this study, a dedicated training session on safety event reporting was organized to help the research team further clarify the requirements for the identification, documentation, and reporting of adverse events. During the discussion session, attendees had in-depth exchanges on the inclusion and exclusion criteria, dosing procedures, follow-up arrangements, and quality control, confirming and reaching consensus on the critical steps. The study site and the sponsor will strictly adhere to GCP guidelines and the trial protocol, rigorously control trial quality through meticulous management, fully safeguard participants' rights and safety, and efficiently advance this clinical trial.
About GC801
GC801 Injection is a recombinant IgG-degrading enzyme independently developed by Genecradle Therapeutics, engineered on the basis of the naturally occurring IdeS through protein engineering. Compared with wild-type IdeS, GC801 achieves efficient IgG degradation at lower doses, thereby weakening the IgG antibody-mediated immune barrier and removing the immunological obstacles for therapeutic scenarios that rely on the modulation of IgG antibodies.
In AAV-mediated gene therapy, pre-existing neutralizing antibodies are a critical limiting factor for efficacy and safety. These antibodies recognize AAV capsid proteins and prevent the viral vectors from entering target cells, significantly reducing gene transduction efficiency. Epidemiological data show that approximately 30%–60% of the general population harbor pre-existing neutralizing antibodies against various AAV serotypes, which not only limits the eligible patient population for gene therapy but also constrains the implementation of repeated-dosing strategies.
The indication currently submitted for GC801 Injection is antibody-depletion pre-treatment prior to gene therapy for spinal muscular atrophy type 2 (SMA). SMA is a rare neuromuscular disease, and most patients present with progressive muscle weakness and motor dysfunction. GC101 Injection, an AAV-based gene therapy product independently developed by Genecradle Therapeutics, has demonstrated favorable efficacy and safety data in clinical studies, offering SMA patients a new treatment option that provides long-term benefit from a single administration. Through pre-treatment, GC801 is expected to lower the levels of anti-AAV neutralizing antibodies in patients, improve gene transduction efficiency, and enable more patients to gain access to gene therapy.
The IgG-degrading mechanism of GC801 holds platform value across indications. Given that pre-existing neutralizing antibodies represent a common immunological bottleneck shared by all AAV-mediated gene therapy modalities, GC801 is not only applicable to SMA but is also expected to be adaptable to a wide range of gene therapy scenarios in the future. Furthermore, this mechanism can be extended to other therapeutic scenarios that rely on the modulation of IgG antibodies, providing technical support for the clinical translation of more innovative therapies.