Treatment of diabetic macular edema with an inhibitor of vascular endothelial-protein tyrosine phosphatase that activates Tie2.

Conference Paper

PURPOSE: AKB-9778 is a small-molecule competitive inhibitor of vascular endothelial-protein tyrosine phosphatase (VE-PTP) that promotes Tie2 activation and reduces vascular leakage and neovascularization in mouse models. The purpose of this study was to test the safety, tolerability, pharmacokinetics, and biological activity of AKB-9778 in patients with diabetic macular edema (DME). DESIGN: Open-label, dose-escalation clinical trial. PARTICIPANTS: Four dose cohorts of 6 patients with DME self-administered subcutaneous injections of 5 mg, 15 mg, 22.5 mg, or 30 mg AKB-9778 twice daily for 4 weeks. METHODS: Patients were seen weekly during a 4-week treatment period for safety assessments, best-corrected visual acuity (BCVA) assessment by Early Treatment Diabetic Retinopathy Study protocol, and measurement of central subfield thickness (CST) by spectral-domain optical coherence tomography. Additional safety assessments were performed at 6, 8, and 12 weeks. MAIN OUTCOME MEASURES: Safety assessments, change from baseline BCVA, and change from baseline CST. RESULTS: All doses were well tolerated. A modest, transient reduction in blood pressure and adverse events consistent with vasodilatory activity of AKB-9778 emerged at doses of 22.5 mg or more twice daily. At the week 4 primary end point, BCVA improved 5 letters or more from baseline in 13 of the 18 patients receiving 15 mg or more twice daily; 1 patient improved by 10 to 15 letters, and 2 patients improved by more than 15 letters. Among 18 patients receiving 15 mg or more twice daily, CST decreased by more than 100 μm in 5 patients and by 50 to 100 μm in 2 patients. There was a significant correlation between reduction in CST and improvement in BCVA. CONCLUSIONS: No safety concerns were identified after systemic administration of AKB-9778 for 4 weeks in patients with DME, and doses of 15 mg or more twice daily reduced macular edema and improved vision in some patients. This is a preliminary demonstration of clinical safety and efficacy of a VE-PTP inhibitor and Tie2 activator.

Full Text

Duke Authors

Cited Authors

  • Campochiaro, PA; Sophie, R; Tolentino, M; Miller, DM; Browning, D; Boyer, DS; Heier, JS; Gambino, L; Withers, B; Brigell, M; Peters, K

Published Date

  • March 2015

Published In

Volume / Issue

  • 122 / 3

Start / End Page

  • 545 - 554

PubMed ID

  • 25439435

Electronic International Standard Serial Number (EISSN)

  • 1549-4713

Digital Object Identifier (DOI)

  • 10.1016/j.ophtha.2014.09.023

Conference Location

  • United States