Existing anti-VEGF therapies effectively reduce vascular leakage in the short-ter but require repeated intravitreal injections every 4 to 12 weeks to maintain efficacy, which imposes a significant burden on patients and caregivers, leading to suboptimal long-term compliance.

By acting on multiple disease-driving pathways, PST-809 is designed as a first-in-class treatment, clearly differentiated from conventional anti-VEGF agents due to its unique ability to target both VEGF-dependent and VEGF-independent pathways. Notably, decorin among other targets, inhibits the TGF-β pathogenic cascade involved in the expression of angiogenic related molecules and mediating inflammation and subretinal fibrosis formation. The inhibition of TGF-β signaling has been shown to reduce the CNV formation and firbrosis⁸.

Moreover, the sustained intraocular expression of both therapeutic proteins has the potential to reduce significantly reinjection frequency, thus lowering treatment burden and improving patient compliance.

Thanks to its dual and complementary mechanism of action and its potential for long-lasting efficacy, PST-809 holds the potential to address patient that are not properly responding to the current anti- VEGF-based treatment.