Aerpio Therapeutics, Inc., a clinical-stage biopharmaceutical company focused on advancing innovative therapies for vascular diseases, today announced the successful completion of its Phase 1b/2a study of AKB-9778 for the treatment of diabetic macular edema (DME) and the closing of a new $9 million extension to the $27 million Series A raised in 2012. The financing round was led by Satter Investment Management LLC and joined by Novartis Venture Funds, Kearny Venture Partners, Venture Investors LLC, Triathlon Medical Ventures, and Athenian Venture Partners. Proceeds will support ongoing development of AKB-9778, including an expanded clinical program with a Phase 2 study to confirm monotherapy efficacy and explore adjunctive efficacy with a VEGF inhibitor in DME patients. Muneer Satter, Chairman of Satter Investment Management LLC, will become co-chairman of the Aerpio board with the completion of this financing.

AKB-9778 is a first-in-class inhibitor of human protein tyrosine phosphatase beta (HPTPβ) that works to activate Tie2, a receptor on vascular endothelial cells that stabilizes blood vessels, preventing abnormal blood vessel growth and vascular leak. The 28-day Phase 1b/2a ascending dose study of AKB-9778 evaluated the safety and efficacy of AKB-9778 in 24 patients with DME. AKB-9778 was well tolerated throughout 28 days of dosing and produced meaningful changes in retinal thickness and vision gain in some of the treated patients.

'These data support our hypothesis that activation of Tie2 by AKB-9778 is capable of stabilizing retinal blood vessels to reduce edema and improve vision in patients with DME,' said Kevin Peters, MD, Chief Scientific Officer of Aerpio. 'The additional funding that is now in hand allows us to expand the clinical program for AKB-9778, including greater flexibility in our trial design to obtain proof of concept, both as a monotherapy and as an adjunct with a VEGF inhibitor, in the treatment of DME.'

'I am very pleased to be supporting further clinical development of this promising compound,' said Mr. Satter. '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. We believe that 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.'

About AKB-9778

AKB�9778 is a first-in-class small molecule that works by inhibiting the Human Protein Tyrosine Phosphatase β (HPTPβ) enzyme, which acts as a negative regulator of the Tie2 receptor. By inhibiting this negative regulator, Tie2 signaling is restored, overcoming the effects of the Ang2�induced vascular destabilization. Aerpio is currently focusing development of its lead candidate, AKB�9778, in diabetic macular edema (DME), however, Tie2 activators have potential utility in a range of important clinical indications. In a Phase 1b/2a study in DME patients, AKB-9778 was well tolerated throughout 28 days of dosing, with evidence of disease improvement in some patients. A Phase 2 study to confirm efficacy of AKB-9778 in patients with DME is expected to begin early in 2014.

About Aerpio Therapeutics

Aerpio Therapeutics, Inc. is a clinical�stage biopharmaceutical company focused on advancing innovative therapies for vascular diseases. Aerpio is a leader in the development of small molecule drugs based on Tie2 activation and the stabilization of hypoxia-inducible factor 1α (HIF�1α). The Company's lead program, AKB�9778, is a first�in�class stabilizer of the Tie2 pathway and is in clinical development for diabetic macular edema. More information is available at www.aerpio.com.