US-based clinical-stage biopharmaceutical firm Aerpio Therapeutics has completed its Phase Ib/IIa study of AKB-9778, a first-in-class inhibitor of human protein tyrosine phosphatase beta (HPTPß), for the treatment of diabetic macular edema (DME).
The Phase Ib/IIa trial assessed the safety and efficacy of AKB-9778 in 24 DME patients and also showed that the inhibitor was well tolerated throughout 28 days period of dosing and produced meaningful changes in retinal thickness and vision gain in some of the treated patients.
Aerpio chief scientific officer Kevin Peters said: "These data support our hypothesis that activation of Tie2 by AKB-9778 is capable of stabilising retinal blood vessels to reduce edema and improve vision in patients with DME."
AKB-9778 helps in activating Tie2, a receptor on vascular endothelial cells, which stabilises blood vessels, preventing abnormal blood vessel growth and vascular leak.
The company has also announced the closing of a new $9m extension to the $27m Series A raised in 2012, which was led by Satter Investment Management and joined by Novartis Venture Funds, Kearny Venture Partners, Venture Investors, Triathlon Medical Ventures and Athenian Venture Partners.
According to the company, the funding will enable them to expand the clinical program for AKB-9778, including greater flexibility in its trial design to obtain proof-of-concept, both as a monotherapy and as an adjunct with a VEGF inhibitor, in the treatment of DME.
Following completion of the financing, Satter Investment Management chairman Muneer Satter will become co-chairman of the Aerpio board.
Satter said that AKB-9778 has the potential to be game-changing for this patient population, as the product profile could make it well-suited to be the first self-administered drug to treat DME.
"Although VEGF inhibitors have shown application in DME, administration is currently limited to intravitreal injection and significant unmet need still exists for these patients," Satter said.
By inhibiting HPTPß, a negative regulator of the Tie2 receptor, AKB-9778 restores Tie2 signaling, reducing vascular leak and pathologic neovascularisation.
The company believes AKB-9778 could be effective in patients with DME as a monotherapy and could improve the effectiveness of VEGF inhibitors when used in combination with those drugs.
AKB-9778 is currently under development for the treatment of diabetic macular edema and diabetic retinopathy (DR) and breast cancer.
Image: Diabetic macular edema. Photo: courtesy of GeeJo.