The Phase I/IIa PARTRIDGE study: Investigating BI 765128 in patients with diabetic macular ischemia

Abstract

Purpose : Diabetic macular ischemia (DMI) is a complication of diabetic retinopathy (DR) that can result in vision loss. Despite its disease burden, DMI currently has no approved treatment. The two-part PARTRIDGE study (NCT04919499) is a Phase I/IIa trial evaluating the safety and efficacy of intravitreal BI 765128 in patients with DR and evidence of DMI.

Methods : To participate in the PARTRIDGE study, subjects must have evidence of DMI. In completed Part A, DMI was defined as any disruption in retinal vascularity in the superficial and/or deep retinal plexus as assessed by optical coherence tomography angiography (OCTA) imaging. In Part B, the definition has been refined to include only subjects with a foveal avascular zone (FAZ) ≥0.5 mm² on OCTA. Part A was single rising dose (SRD), non-randomized, open label and uncontrolled. Subjects (N=12) received a low, medium or high single dose of BI 765128. The primary endpoint was the number of subjects with ocular dose-limiting events from drug administration to Day 8. The ongoing Part B is multiple dosing, randomized, masked and sham-controlled. Subjects (planned N=30) in Part B are receiving the high dose of BI 765128 from Part A. In addition to safety, change in FAZ size and best-corrected visual acuity are being assessed as secondary endpoints in Part B.

Results : The SRD part is complete. No drug-related or dose-limiting adverse events (AEs) were reported in Part A. In total, five AEs were reported in four subjects, including one that was ocular and procedure-related (eye pain; high dose) and one that was ocular but not procedure-related (blurred vision; medium dose). To date, ten subjects have been randomized to the ongoing MD part.

Conclusions : PARTRIDGE is one of the first clinical trials worldwide to examine a treatment for DMI. Single doses of BI 765128 were well tolerated in Part A. Part B is assessing the safety and efficacy of multiple doses of BI 765128.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.