Inotek Pharmaceuticals Raises $21 Million to Support Ongoing Clinical Development of Trabodenoson, a Novel Eye Drop for the Treatment of Glaucoma

— Phase 2 study to evaluate trabodenoson in combination with latanoprost expected to begin in 2013 —

LEXINGTON, MA — September 27th, 2013 — Inotek Pharmaceuticals Corp., a leader in the development of innovative products for the treatment of glaucoma, today announced that it has closed on a $21 million financing. Proceeds from this financing will be used to advance Inotek’s lead product, trabodenoson, a novel eye drop that increases aqueous fluid outflow via the eye’s trabecular meshwork, through Phase 2 studies in glaucoma. Later this year, Inotek expects to initiate a Phase 2 study designed to evaluate the efficacy and safety of trabodenoson when combined with latanoprost for the treatment of glaucoma patients whose intraocular pressure (IOP) is not well controlled by latanoprost therapy alone. All of the company’s existing investors, including Devon Park Bioventures, Rho Ventures, Care Capital, Medimmune Ventures and Pitango Venture Capital, participated in the financing. Concurrent with the equity financing, Inotek also secured $7 million in venture debt led by Horizon Technology Finance Corporation (NASDAQ: HRZN).

In a recently completed multi-dose Phase 2 study, trabodenoson, given as monotherapy, was shown to significantly reduce IOP in glaucoma patients, achieving efficacy in the range of the market leading prostaglandins, such as latanoprost.

“Based on the trabodenoson data that I have reviewed to date, this molecule has the potential to be an important addition to the tools we now have to reduce intraocular pressure, and ideally the attendant optic nerve neuropathy that leads to vision loss in patients with glaucoma,” said Jonathan Myers, MD, Associate Attending Surgeon on the Glaucoma Service at Wills Eye Hospital and Associate Professor of Ophthalmology at Jefferson Medical College. “I am excited to see the company investing in additional studies which are needed to confirm this early promise, and to move the product closer to eventual availability for glaucoma patients in need.”

“Trabodenoson has already demonstrated very encouraging efficacy as a monotherapy as well as excellent safety and ocular tolerability, so we look forward to evaluating the drug’s efficacy and safety when combined with latanoprost as part of our next Phase 2 study,” said Rudolf Baumgartner, MD, Inotek’s Chief Medical Officer.”

About Trabodenoson for Glaucoma

Trabodenoson is a drop-administered drug candidate in Phase 2 development for the treatment of glaucoma, a leading cause of blindness globally. It is broadly accepted that lowering intraocular pressure (IOP) in glaucoma patients is the only proven means of slowing the progression of vision loss. Trabodenoson is believed to reduce intra-ocular pressure by increasing aqueous fluid outflow via the eye’s trabecular meshwork, a novel mechanism of action that is significantly differentiated from currently approved products, as well as all others in development.

Current products for glaucoma, such as prostaglandins, lower IOP by either reducing the inflow of fluid in the eye or by increasing its drainage through a secondary outflow pathway in the eye – the uveoscleral pathway. However, none of these drugs safely and effectively target the trabecular meshwork, the primary outflow pathway where most fluid exits the eye. The trabecular meshwork comprises a pressure-sensitive mechanism through which healthy eyes maintain a normal, safe ocular pressure (IOP). As the eye ages and glaucoma advances, flow through the eye’s trabecular meshwork grows increasingly difficult. Trabodenoson has been shown to increase the natural metabolic activity of the trabecular meshwork, by up-regulating proteases found in the eye. These proteases are responsible for clearing out hydrolyzed proteins, which block flow through the trabecular meshwork, thus restoring the eye to a more normal, healthy state with greater potential for fluid outflow.

Many patients do not respond adequately to the current IOP-lowering products, and up to 40% of these patients are treated with a combination of products in the hope of achieving targeted reductions in IOP. As a result, there remains a significant unmet need for innovative glaucoma products that can complement the existing drugs by acting on the trabecular meshwork to provide improved IOP-lowering efficacy. In animal models, trabodenoson’s IOP-lowering activity has been shown to significantly enhance the effect of several existing glaucoma medications, including the prostaglandin latanoprost. Further, in the clinical trials to date, trabodenoson was found to be safe and well tolerated as monotherapy, making it an ideal candidate for combination with marketed drugs such as latanoprost.

About Horizon Technology Finance

Horizon Technology Finance Corporation is a business development company that provides secured loans to development-stage companies backed by established venture capital and private equity firms within the technology, life science, healthcare information and services, and clean-tech industries. The investment objective of Horizon is to maximize total risk-adjusted returns by generating current income from a portfolio of directly originated secured loans as well as capital appreciation from warrants to purchase the equity of portfolio companies. Headquartered in Farmington, Connecticut, with regional offices in Walnut Creek, California and Reston, Virginia, Horizon is externally managed by its investment advisor, Horizon Technology Finance Management LLC. Horizon’s common stock trades on the NASDAQ Global Select Market under the ticker symbol “HRZN”. In addition, Horizon’s 7.375% Senior Notes due 2019 trade on the New York Stock Exchange under the ticker symbol “HTF.” To learn more, please visit www.horizontechnologyfinancecorp.com. Contact: Chris Mathieu, Chief Financial Officer, (860) 144-1798, mad@horzontechfnance.com.

About Inotek

Inotek is a leader in the development of innovative drugs to address significant diseases of the eye, with a major focus on glaucoma. Inotek’s lead product candidate trabodenoson has demonstrated clinically meaningful efficacy and tolerability in late-stage glaucoma clinical trials. The Company believes trabodenoson will be a first-in-class breakthrough treatment that can be used alone or combined with other IOP-lowering products because it increases the outflow of aqueous humor through the trabecular meshwork, the primary drainage system used by healthy eyes to maintain normal IOP. The Company is located in Lexington, MA. For further information on Inotek, please visit www.inotekcorp.com.