– EBI-005 Demonstrated Statistically Significant Improvements in Ocular Itching, Tearing and Nasal Symptoms in a Conjunctival Allergen Provocation Model –
– Study Does Not Meet Primary Endpoint Using Environmental Exposure Chamber Model –
– EBI-005 was Well Tolerated in this Study with no Drug-Related Serious Adverse Events –
– Conference Call Scheduled for 8:30 a.m. ET –

CAMBRIDGE, MA, USA I October 1, 2014 I Eleven Biotherapeutics, Inc. (Nasdaq: EBIO), a clinical-stage biopharmaceutical company discovering and developing protein therapeutics to treat diseases of the eye, today announced top-line results from a Phase 2 study of its lead drug candidate, EBI-005, in patients with moderate to severe allergic conjunctivitis. The company ran this Phase 2 study using two distinct repetitive allergen challenge models: a modified Conjunctival Allergen Provocation Test (CAPT) model; and a modified Environmental Exposure Chamber (EEC) model. In the CAPT model, patients treated with EBI-005 showed statistically significant improvements in mean change from baseline in patient reported ocular itching compared to vehicle-control, one of the secondary endpoints pre-specified in the statistical analysis plan, at the second to last (p = 0.033) and final (p = 0.045) assessment time points. This Phase 2 study did not meet the primary endpoint of reduction in mean ocular itching in patients treated with EBI-005 compared to vehicle-control in the EEC model.

“We are very pleased with the top-line safety and efficacy results of this Phase 2 clinical study. Ocular itching is an important clinical symptom for patients with allergic conjunctivitis and one of the reasons for seeking medical intervention that is most frequently reported by these patients,” said Abbie Celniker, PhD, President and Chief Executive Officer. “The positive result in the CAPT model will help us to determine our path forward with EBI-005 as a potential new treatment option for patients with moderate to severe allergic conjunctivitis, and we have a goal of finalizing our plans early next year. In addition, we are also looking forward to the completion of our first pivotal, Phase 3 clinical study of EBI-005 in patients with dry eye disease and to report top-line results of that trial in early 2015.”

EBI-005 is a novel, topically administered Interleukin-1 (IL-1) receptor blocker designed to bind and block the IL-1 receptor to prevent transmission of biological signals responsible for many of the signs and symptoms of ocular surface diseases. The use of EBI-005 in allergic conjunctivitis is based on the role that elevated levels of IL-1 play in the initiation and maintenance of the itching and other symptoms associated with late-phase allergic conjunctivitis.

This Phase 2 study was designed to identify an appropriate model of late phase ocular allergy response and to evaluate the safety and efficacy of EBI-005 in patients with moderate to severe allergic conjunctivitis. To identify the model system that reflects the more severe forms of ocular allergy experienced by allergic conjunctivitis patients, the company conducted a 159-subject, randomized, vehicle-controlled, Phase 2 study enrolling subjects in modified CAPT and EEC models. Unlike the models used for the approval of drugs to treat early phase ocular allergic responses, these models incorporated allergen challenges over multiple consecutive days prior to and during study drug treatment, with disease assessments at multiple time points over the two and one-half week period after commencement of treatment.

In addition to demonstrating statistically significant improvements in the change from baseline in patient reported ocular itching, a pre-specified secondary endpoint, the subjects with moderate to severe allergic conjunctivitis randomized to the CAPT model who received EBI-005 showed improvements compared to vehicle-control on the pre-specified exploratory endpoints of ocular tearing at the second to last (p = 0.027) and final (p = 0.044) assessments and associated nasal symptoms at the second to last (p = 0.004) and final (p = 0.011) assessment time points. In the EEC model, there were no observed differences between patients treated with EBI-005 and vehicle-control on the endpoints of ocular tearing or associated nasal symptoms; however, there was a significant improvement in pre-specified exploratory endpoint of lid swelling in patients treated with EBI-005 compared to vehicle-control at the second to last (p = 0.011) and final (p = 0.037) assessment time points, which was not seen in the CAPT model. There were no observed differences between patients treated with EBI-005 and vehicle-control on the additional secondary and exploratory endpoints of conjunctival redness, conjunctival chemosis, follicular/papillary response, or mucus discharge in the CAPT or EEC models. The comprehensive results of the study are expected to be submitted for presentation at an upcoming ophthalmology conference.

The safety and tolerability of EBI-005 compared to vehicle-control was also evaluated in this Phase 2 study. EBI-005 was generally well-tolerated, with no treatment-related serious adverse events and no immunogenicity detected. Most adverse events observed in the study were mild and similarly distributed between the vehicle-control and EBI-005-treated patients.

“Based on these results, we believe we have identified an allergen challenge model for evaluating late-phase allergic responses in patients with moderate to severe allergic conjunctivitis,” said Michael H. Goldstein, MD, MBA, and Vice President of Medical Research at Eleven Biotherapeutics. “These results are consistent with our hypothesis that the late-phase allergic response is driven in part by increases in IL-1 activity. Topical administration with EBI-005 offers the potential to mediate this response and provide relief to those patients who are not adequately treated by the current standard of care.”

“There is considerable unmet need for an alternative treatment in moderate to severe allergic conjunctivitis, as many patients of this type are not adequately treated by current therapies,” said Victor L. Perez, MD, Professor of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Heath System. “These patients are often treated with corticosteroids, which carry the risk of steroid-related adverse events, including blindness, and require frequent patient monitoring.”

Conference Call Information:

Eleven Biotherapeutics’ management team will host a conference call and audio webcast today, October 2, 2014, at 8:30 a.m. ET to discuss the top-line Phase 2 clinical study results of EBI-005 in allergic conjunctivitis. To access the conference call, please dial (844) 831-3025 (domestic) or (315) 625-6887 (international) at least five minutes prior to the start time and refer to conference ID 14529893.

An audio webcast of the call will also be available on the Investors & Media section of the Company’s website www.elevenbio.com. An archived webcast will be available on the Company’s website approximately two hours after the event and will be available for 30 days.

About Allergic Conjunctivitis

Allergic conjunctivitis (AC) is an inflammatory disease of the conjunctiva, the membrane covering the white part of the eye, caused primarily from a reaction to an allergen such as pollen or pet dander. This inflammation results in redness, acute itching tearing and associated nasal symptoms. According to the National Health and Nutrition Examination Survey III, AC affects 15% to 40% of the United States population and ranges in clinical severity from relatively mild, common forms to more severe chronic forms that may cause impaired vision and blindness. We believe that prolonged and severe cases of AC are characterized by an inflammatory process that is mediated by IL-1. IL-1 stimulates the maturation and recruitment of antigen presenting cells and dendritic cells that perpetuate or exacerbate the allergic response. IL-1 also mediates the expression of key chemokines that activate and direct pathogenic white blood cells to the ocular surface.

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 dry eye disease and allergic conjunctivitis. 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 and pain associated with dry eye disease and the redness, itching and other symptoms associated with allergic conjunctivitis. EBI-005 has been evaluated in a Phase 2 study in patients with moderate to severe allergic conjunctivitis and is currently being evaluated in a pivotal Phase 3 study in dry eye disease.

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.

SOURCE: Eleven Biotherapeutics