Ocular Therapeutix, Inc. announced the release of interim 10-month data from its U.S. phase 1 clinical trial evaluating OTX-TKI for treating age-related macular degeneration (AMD), diabetic retinopathy, and other retinal diseases.
Tell me about OTX-TKI.
OTX-TKI is an investigational bioresorbable, intravitreal hydrogel implant that incorporates axitinib, which is a small-molecule tyrosine kinase inhibitor (TKI) with anti-angiogenic properties.
Talk about the trial.
The ongoing trial (NCT04989699), is a prospective, multi-center, randomized, controlled study with 21 patients who had previously been treated with anti-vascular endothelial growth factor (anti-VEGF) therapy.
Patients were randomized 3:1 to an arm receiving OTX-TKI as a 600 µg dose in a single implant followed by an administered injection of 2 mg aflibercept every four weeks, and an arm receiving only 2 mg aflibercept injected every eight weeks.
Did anything unusual happen?
Funny you should ask… one patient with the OTX-TKI arm did not receive treatment that went with the study protocol—they incorrectly received an aflibercept injection in lieu of sham at the Month 3 and 5 visits. Researchers have since removed the subject from their efficacy analysis.
What does the interim data show?
As of December 12, 2022, the 10-month data cutoff date, OTX-TKI was found to be generally well tolerated and had no drug-related ocular or system serious adverse events (SAEs).
What else?
Per previously reported data, endophthalmitis was observed as an SAE in one patient from the OTX-TKI arm, relating to the injection procedure and occuring after the Month 1 aflibercept injection.
Show me the numbers.
Patients treated with the single OTX-TKI implant exhibited stable and sustained best-corrected visual acuity (BCVA), with a mean change from baseline of -0.3 letters, and center subfield foveal thickness (CSFT), mean change from baseline of -1.3 µm, in the OTX-TKI arm at Month 10.
This was similar to the aflibercept arm, which had a mean change from BCVA baseline of -0.8 letters and a mean change from CSFT baseline of -4.5 µm.
Patients who were rescue-free at Month 7 (73%) continued to show OTX-TKI’s extended duration of action at Month 10. In totality, OTX-TKI-treated patients showed a 92% reduction in treatment burden up to 10 months.
Significance?
If OTX-TKI’s data for wet AMD continues to show promising results, it could have the potential to fill the unmet need for a retinal disease treatment with an efficacy that extends beyond three to four months with a single injection.
What’s next?
Ocular Therapeutics expects to discuss potential future clinical trial requirements with the FDA in the near future. Pending discussion and securing financing, the company plans to initiate a wet AMD pivotal trial in Q3 of 2023.
It will also continue to follow subjects from phase 1 through their respective one-year anniversaries.