The Korea Exchange (KRX) on the 1st rejected Caregen's disclosure of phase 1 clinical trial results submitted to the U.S. Food and Drug Administration (FDA) for CG-P5, a candidate treatment for wet age-related macular degeneration (Wet AMD).
The reason was insufficient data on key indicators based on OCT (optical coherence tomography), an imaging technique that visualizes the internal structure of the eye in three dimensions, including CST (central subfield thickness), CRT (central retinal thickness), and TMV (total macular volume).
Caregen said, "This phase 1 used a central reading structure in which an American specialty reading center uniformly analyzed OCT images taken at six clinical sites," adding, "Because this process has not yet been completed, the CSR (clinical study report) has not been prepared."
According to the company, the reading center is proceeding with procedures such as ▲ image quality verification (QC) ▲ requests to retake inaccurate images ▲ confirmation of patient-specific timepoints. A Caregen official added, "The schedule was partially adjusted due to the U.S. Thanksgiving holiday, and the calculation of quantitative indicators was delayed due to schedule constraints on expert readers."
The company said the delay in central reading is not due to data loss or errors but an additional verification process to improve accuracy. The CSR receipt schedule has been readjusted to the 31st.
According to the company, meaningful signals were identified in this phase 1. In BCVA (best-corrected visual acuity), which indicates the degree of visual improvement, the CG-P5 arm improved by +0.2 letters, while the placebo arm worsened by –8.4 letters, a difference of about 8.6 letters (equivalent to two lines on a vision chart).
Caregen said, "The partial narrowing of the inter-arm difference compared with the interim analysis was due to the placebo arm's increased use of rescue therapy temporarily correcting the worsening," adding, "CG-P5 maintained statistical significance in the final analysis." Rescue therapy refers to an additional structural adjunct therapy administered when it becomes difficult to maintain the condition with existing treatment alone.
The company also said the reduction in choroidal neovascularization (CNV) lesion size—an abnormal growth of blood vessels under the retina that damages vision—was greatest in the CG-P5 arm among the three arms, and the frequency of rescue therapy with CG-P5 was about three times lower than with placebo.