The primary endpoint was reached, a mean gain from baseline was observed in a middle dose (25mg/ml), reaching statistical significance (p = 0.045). 71.4% of patients in the middle dose levels maintained visual acuity over the 6-week study period. The study evaluated the preliminary efficacy and safety of three dose levels of SYL1801, a novel siRNA administered via eye drops found that the middle concentration (25mg/ml) was the one showing better activity.
Sylentis, a wholly owned subsidiary of PharmaMar (MSE:PHM), announced topline results from the SYL1801_II study, a Phase IIa dose-ranging trial evaluating SYL1801, an investigational siRNA therapy administered via eye drops unlike other treatments which require intravitreal injection, for the treatment of neovascular Age-Related Macular Degeneration (nAMD).
The double-blinded study evaluated three parallel dose level cohorts of SYL1801 in treatment-naïve eyes of nAMD patients though 42 days. A total of 99 subjects were enrolled across 21 centers in Europe. The primary endpoint was to evaluate the effect of SYL1801 on the change from baseline to the final visit (end of treatment) in BCVA (Best Corrected Visual Acuity) score. All dose-levels of SYL1801 maintained visual acuity similarly throughout the duration of the study. The middle concentration of 25mg/ml achieved a statistically significant improvement of visual acuity at 42 days (p=0.045).
In this clinical trial, SYL1801 was well tolerated with no ≥3 treatment related adverse events. Eric Nudleman, MD, PhD. Associate Professor of Clinical Ophthalmology at UC San Diego Shiley Eye Institute said, “the anatomic changes observed in these patients may be related to an effect of the investigational agent, and further investigation is warranted”.
Andreas Segerros, CEO of Sylentis, comments that “with these data from this explorative study of SYL-1801 we are encouraged to put efforts into the subsequent clinical research program, with proper guidance from the patient outcomes in the concluded study.”
The results of the study have been presented at ARVO 2025 in Salt Lake City, Utah (USA), on May 4 th , during the poster session titled AMD, Clinical Research. SYL1801 is a novel siRNA targeting the notch-regulated ankyrin repeat protein (NRARP). The results of this study support further investigation of SYL1801 and pave the way for the next stage of clinical development, bringing Sylentis one step closer to offering a new therapeutic option for patients affected with retinal diseases worldwide.