Kiora Pharmaceuticals, Inc. (KPRX), ("Kiora" or the "Company") announced additional data from ABACUS-1, the Phase I/II clinical trial in patients with retinitis pigmentosa showing KIO-301 significantly increased brain activity, specifically in the visual cortex, relative to baseline, as assessed by functional MRI (fMRI). This standard method of measuring visual cortex activity, in response to visual stimuli, is performed by assessing the quantitative change in voxels, a three-dimensional equivalent of a pixel at each visit. KIO-301 is a small molecule photoswitch providing light sensitivity to retinal cells capable of transmitting neural signals to the brain following the loss of native photoreceptors (rods and cones).
The results were presented May 5, 2024 by Professor Robert James Casson, DPhil, Head of the Ophthalmic Research Lab at The University of Adelaide, at the Association for Research in Vision and Ophthalmology (ARVO) annual meeting in Seattle, WA. Additional key findings include the following:
A statistically significant increase in visual cortex activity from baseline at all timepoints assessed (1574.0 ± 689.7 voxels at d2, 1061.8 ± 632.1 voxels at d14, 1110.8 ± 478.4 voxels at d28, p<0.05 for all timepoints, n=12).
A statistically significant increase in visual cortex activity was measured in both cohorts, those with baseline vision of counting fingers or hand motion range and those with baseline vision of bare light perception or no light perception.
A more pronounced increase in visual cortex activity was found in patients with better baseline vision.
The increase was time-dependent following initial administration of KIO-301, consistent with improvements in visual acuity, visual field, and functional improvements that mimic performing everyday activities.
"These data further support KIO-301's underlying potential to restore meaningful vision, both clinically and mechanistically," explained Professor Casson. "fMRI has allowed us to visually capture and quantify the changes happening in the vision processing center of the brain, helping us connect the dots between the observed functional outcomes and the drugs' mechanism of action."
"The fMRI results reinforce our understanding of KIO-301's mechanism of action, as well as the assertion that conferring light sensitivity to cells other than the native rods and cones, can positively impact vision," added Eric Daniels, MD, Chief Development Officer of Kiora. "Importantly, this data is consistent with improvements in functional endpoints assessing change in patients' everyday activities that we and regulatory bodies believe are essential for drug approval. Our next step is to complete ongoing validation of functional endpoints and initiate a double-masked, multi-center Phase II clinical trial (ABACUS-2) in cooperation with our development and commercialization partner, Théa Open Innovation."