Biotechnology company Kodiak Sciences Inc (Nasdaq: KOD) announced on Monday that new data from its Phase 1b APEX study of KSI-101 showed rapid and clinically meaningful vision gains in patients with macular edema secondary to inflammation (MESI). Results were presented at the Retina Society's 58th Annual Scientific Meeting in Chicago.

Patients achieved significant improvements as early as week 4, with more than half of those receiving the 5 mg and 10 mg doses gaining at least 15 letters on the eye chart by week 12. A single dose resolved intra-retinal and sub-retinal fluid in most patients, with over 90% achieving retinal dryness by week 8. Mean improvements in best corrected visual acuity at week 12 were +10.7 letters and +12.1 letters for the 5 mg and 10 mg cohorts, respectively.

KSI-101 also demonstrated strong anatomical responses, with retinal thickness reductions of 216 and 240 microns at the higher dose levels. A separate cohort of patients with diabetic macular edema also showed visual and anatomical benefits. Across groups, the therapy was well tolerated with a favourable safety profile.

Based on these findings, Kodiak has advanced the 5 mg and 10 mg doses into its ongoing Phase 3 PEAK and PINNACLE trials, designed to evaluate efficacy across a wide spectrum of MESI patients. Topline data are expected in late 2026 or early 2027.

KSI-101 is a novel bispecific protein targeting IL-6 and VEGF, addressing an area of unmet need as no approved intravitreal biologic therapies currently exist for MESI. Kodiak said the therapy could establish a new treatment category distinct from the existing anti-VEGF market.