Objective:

To evaluate the safety and efficacy of tiespectus (MK-8748) in patients with branch retinal vein occlusion (BRVO) as part of the phase 1/2a RIOJA trial.

Approach:

• Study Design: An open-label dose-escalation study enrolling 12 treatment-naïve patients with macular edema secondary to BRVO, with four ascending-dose cohorts (1 mg, 4 mg, 7 mg, and 10 mg).
• Treatment Administration: Patients received intravitreal injections every 4 weeks for a total of 3 doses, with dose escalation proceeding only after safety assessments.

Key Findings:

• All dose levels were well tolerated with no drug-related safety concerns.
• Mean best-corrected visual acuity (BCVA) improved by 16.7 ETDRS letters at week 12.
• Mean central subfield thickness (CST) decreased by 157.8 µm across all dose cohorts.
• Improvements in vision and retinal anatomy were observed as early as 1 week after treatment.

Interpretation:

The study primarily aimed to evaluate safety, but significant improvements in visual acuity and retinal structure were noted.

Limitations:

• The study involved a small sample size of 12 patients.
• Long-term durability and efficacy assessments are ongoing.

Conclusion:

Tiespectus shows promise as a dual-pathway inhibitor for retinal vascular diseases, with ongoing studies in neovascular age-related macular degeneration (nAMD).

Sources:

• ASRS Meeting Presentation