(EBIO) First Patients Dosed with EBI-005 in Phase 3 Allergic Conjunctivitis Study

Eleven Biotherapeutics, Inc. (Nasdaq: EBIO), a clinical-stage biopharmaceutical company discovering and developing protein therapeutics to treat diseases of the eye, today announced dose administration for the first patients in a Phase 3 study of EBI-005 for the treatment of moderate to severe allergic conjunctivitis. This Phase 3 study was designed and initiated following the completion in October 2014 of a Phase 2 study in which EBI-005 exhibited biological activity in improving the symptoms of late-phase allergic responses in patients with moderate to severe allergic conjunctivitis. This included statistically significant improvements in mean change from baseline in patient reported ocular itching, tearing and associated nasal symptoms compared to vehicle-control at the second to last and final assessment time points following allergen exposure in a modified direct conjunctival allergen provocation test (CAPT) model.

“Patient dosing in this Phase 3 study represents a significant step forward in the clinical development of EBI-005, a drug candidate with potential for the treatment of moderate to severe allergic conjunctivitis patients who are refractory to standard of care treatments for ocular allergy,” said Abbie Celniker, PhD, Chief Executive Officer of Eleven Biotherapeutics. “We look forward to reporting top line data from this Phase 3 study in the first quarter of 2016.”

“Many allergic conjunctivitis patients develop a late-phase severe allergic response which is not treated with antihistamines or mast cell stabilizers, the current standard of care. The ocular itching, tearing, redness and other symptoms, which if left untreated can become severe, resulting in chronic ocular pain, corneal scarring and distortion of vision. Currently, many of these patients are treated with topical steroids, which have a number of adverse side effects, including increased intraocular pressure and cataract formation,” said Dr. Victor Perez, Professor of Ophthalmology at Bascom Palmer Eye Institute. “EBI-005 offers the potential to mediate this late-phase allergic response by blocking the interleukin-1 (IL-1) receptor, believed to be responsible for the symptoms of ocular surface inflammation in diseases like allergic conjunctivitis, with an acceptable, long-term safety and tolerability profile.”

This multi-center, double-masked, randomized, vehicle controlled Phase 3 pivotal trial is designed to evaluate the safety and efficacy of EBI-005 for up to four weeks in patients with moderate to severe allergic conjunctivitis in an environmental setting. Approximately 250 patients will be randomized 1:1 to receive treatment with EBI-005 or with vehicle. If the results of this first Phase 3 trial are favorable, Eleven intends to initiate a second Phase 3 trial in the second half of 2016.

About EBI-005

Eleven Biotherapeutics’ most advanced product candidate is EBI-005, a novel, topically-administered interleukin-1 (IL-1) receptor blocker in development as a protein therapeutic for inflammatory diseases at the surface of the eye. The EBI-005 program is based on the role that elevated levels of the inflammatory cytokine IL-1 play in the initiation and maintenance of the inflammation, pain, redness, itching and other symptoms associated with ocular surface diseases. EBI-005 is currently in Phase 3 clinical development for the treatment of moderate to severe allergic conjunctivitis. In a completed Phase 2 clinical trial, EBI-005 exhibited biological activity in improving the symptoms of late-phase allergic responses in patients with moderate to severe allergic conjunctivitis in a (CAPT) model.

About Allergic Conjunctivitis

Allergic conjunctivitis (AC) affects the ocular surface and is characterized by symptoms of ocular itching, ocular tearing, ocular redness and associated nasal symptoms. If allergic conjunctivitis is left untreated or becomes severe, patients may suffer chronic ocular pain and distortion of vision that can significantly reduce their quality of life. Allergic conjunctivitis is a common cause of patient visits to eye care professionals in the United State. Allergic conjunctivitis affects 15% to 40% of the U.S. population. According to Eleven’s primary market research, in the United States 11 million patients seek medical treatment for allergic conjunctivitis annually. Of these patients, approximately 4 million have moderate allergic conjunctivitis and approximately 1.8 million have severe allergic conjunctivitis.

About Eleven Biotherapeutics

Eleven Biotherapeutics, Inc. is a clinical-stage biopharmaceutical company with a proprietary protein engineering platform, called AMP-Rx, that it applies to the discovery and development of protein therapeutics to treat diseases of the eye. The Company’s therapeutic approach is based on the role of cytokines in diseases of the eye, the Company’s understanding of the structural biology of cytokines and the Company’s ability to rationally design and engineer proteins to modulate the effects of cytokines. Cytokines are cell signaling molecules found in the body that can have important inflammatory effects. For more information please refer to the Company’s website www.elevenbio.com.

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