Valitor has presented new preclinical safety data for VLTR-559, its long-acting anti-VEGF drug candidate designed to transform wet age-related macular degeneration (AMD) treatment from frequent injections to a twice-yearly regimen. The data, featured at the Ophthalmology Futures Retina Forum, demonstrated that VLTR-559 was well-tolerated at anticipated clinical doses and exhibited similar preclinical tolerability to approved short-acting anti-VEGF therapies.
Promising Safety Profile in Non-Human Primate Studies
In a dose-finding non-human primate (NHP) toxicology study, VLTR-559 administration was well tolerated across multiple measures of eye health. The study utilized the semiquantitative preclinical ocular toxicology scoring (SPOTS) system to detect ocular inflammation. Results showed that the SPOTS score for vitreous cells was equivalent or better than other marketed anti-VEGF therapies, with no inflammation observed in the aqueous chamber and constant intraocular pressure maintained throughout the study period.
"We are excited to present our most recent in vivo safety data, which build on a series of highly promising results demonstrating VLTR-559 has the capacity to significantly redefine the treatment regimen for wet AMD," said Wesley Jackson, Ph.D., president and chief scientific officer of Valitor. "A well-tolerated and potent anti-VEGF therapy that is administered only twice a year has the potential to improve long-term outcomes for patients."
Extended Tissue Retention Without Compromising Potency
VLTR-559 was developed using Valitor's proprietary multivalent polymer (MVP) technology platform, which enables the drug to remain in ocular tissues three to four times longer than first-generation anti-VEGFs while maintaining potency consistent with approved therapies. In preclinical studies, the drug demonstrated unprecedented durability at the target site without losing therapeutic effectiveness.
The MVP technology platform, which originated at U.C. Berkeley, is based on proprietary multivalent biopolymers coupled with bioactive molecules. This approach allows for independent control of multiple drug attributes, including pharmacokinetic/pharmacodynamic properties, improved target engagement and tissue localization, therapeutic durability, and enhanced safety. Research studies have shown that Valitor's compounds achieve 10-fold increases in potency and up to 5-fold increases in tissue retention.
Addressing Unmet Medical Need in Wet AMD Treatment
Anti-VEGF therapy represents the gold-standard treatment for wet AMD; however, first-generation anti-VEGFs require frequent intravitreal injections and office visits for disease monitoring to prevent long-term efficacy losses. Current market leaders typically require dosing approximately every 8-12 weeks, creating a significant treatment burden for patients.
Jackson emphasized the potential clinical and economic benefits of the twice-yearly regimen: "Additionally, the availability of a longer-acting anti-VEGF can reduce the clinical costs associated with the more frequent doctor visits required by first generation therapies. VLTR-559 was designed to enable a simplified and reliable dosing schedule, a 'treat-and-release' regimen, that facilitates easier management of the disease by both patients and physicians."
Development Timeline and Next Steps
Valitor is currently advancing VLTR-559 through IND-enabling activities with the goal of initiating a Phase 1 clinical study in 2026. The company's lead product is designed to reliably extend the duration of a single dose in humans to six months or more, which would offer substantial benefits for the majority of patients currently requiring more frequent dosing.
The biotechnology company is initially focused on developing long-acting molecules for large ophthalmology markets, leveraging its multivalent biopolymer technology to maximize patient benefits by overcoming limitations of established drug targets.
