Topline Results From ENLIGHTEN-1 Study Expected Mid-2017

DUBLIN, Ireland I May 1, 2017 I Alkermes plc (NASDAQ: ALKS) today announced completion of patient enrollment in ENLIGHTEN-1, the first of two key phase 3 studies in the ENLIGHTEN clinical development program for ALKS 3831, an investigational, novel, once-daily, oral atypical antipsychotic drug candidate for the treatment of schizophrenia. The multinational, randomized, double-blind phase 3 study is designed to evaluate the antipsychotic efficacy of ALKS 3831 compared to placebo over four weeks in patients experiencing an acute exacerbation of schizophrenia. The study also includes a comparator arm of olanzapine, an established atypical antipsychotic agent with proven efficacy but also metabolic liabilities, including significant weight gain. Topline results from the study are expected in mid-2017. ALKS 3831 is designed to provide the strong antipsychotic efficacy of olanzapine with favorable weight and metabolic properties.

“There is a clear and compelling clinical rationale for developing an antipsychotic with the powerful efficacy of olanzapine while addressing the significant weight gain associated with its use,” said Elliot Ehrich, M.D., Chief Medical Officer of Alkermes. “The completion of enrollment of this carefully conducted, multinational study represents an important milestone in the development program for ALKS 3831, as it moves us one step closer to providing this potential, important new treatment option to patients suffering from schizophrenia. We look forward to progressing ALKS 3831 through development and reporting the results of the ENLIGHTEN-1 study in mid-2017.”

ENLIGHTEN-2, the second key study from the ENLIGHTEN development program for ALKS 3831, is ongoing and enrolling patients with data expected mid-2018. The study is designed to evaluate the weight gain profile of ALKS 3831 in patients with schizophrenia over a six-month treatment period compared to olanzapine. The clinical data from the ENLIGHTEN-1 and ENLIGHTEN-2 studies, if successful, will form the basis of a New Drug Application (NDA) to be submitted to the U.S. Food and Drug Administration (FDA) for ALKS 3831 for the treatment of schizophrenia.

About the ENLIGHTEN Clinical Development Program

The ENLIGHTEN clinical development program for ALKS 3831 is comprised of two key studies: a study evaluating the antipsychotic efficacy of ALKS 3831 compared to placebo over four weeks and a study assessing weight gain with ALKS 3831 compared to olanzapine in patients with schizophrenia over six months. The program also includes supportive studies to evaluate the pharmacokinetic and metabolic profile of ALKS 3831, as well as long-term safety.

Further information about the ENLIGHTEN studies can be found at www.clinicaltrials.gov.

About ALKS 3831

ALKS 3831 is a proprietary, investigational medicine designed as a broad-spectrum antipsychotic for the treatment of schizophrenia. ALKS 3831 is composed of samidorphan, a novel, new molecular entity co-formulated with the established antipsychotic agent, olanzapine, in a single bilayer tablet.

Weight gain is a common and clinically relevant metabolic side effect of atypical antipsychotic medications, and olanzapine, commercially available as ZYPREXA®, has one of the highest incidences and greatest amounts of weight gain among the widely prescribed products in this class of drugs.1 ALKS 3831 is designed to provide the strong antipsychotic efficacy of olanzapine and a differentiated safety profile with favorable weight and metabolic properties.

About Schizophrenia

Schizophrenia is a chronic, severe and disabling brain disorder. The disease is marked by positive symptoms (hallucinations and delusions) and negative symptoms (depression, blunted emotions and social withdrawal), as well as by disorganized thinking. An estimated 2.4 million American adults have schizophrenia,2 with men and women affected equally.

About Alkermes

Alkermes plc is a fully integrated, global biopharmaceutical company developing innovative medicines for the treatment of central nervous system (CNS) diseases. The company has a diversified commercial product portfolio and a substantial clinical pipeline of product candidates for chronic diseases that include schizophrenia, depression, addiction and multiple sclerosis. Headquartered in Dublin, Ireland, Alkermes plc has an R&D center in Waltham, Massachusetts; a research and manufacturing facility in Athlone, Ireland; and a manufacturing facility in Wilmington, Ohio. For more information, please visit Alkermes’ website at www.alkermes.com.

SOURCE: Alkermes