A Randomised, Double-Blind, Placebo-Controlled Study Evaluating the Efficacy and Safety of Orvepitant in Subjects With Major Depressive Disorder

The purpose of the current study is to test the safety and the anti-depressant effects of
orvepitant, an investigational antidepressant. Efficacy will be assessed using standard
depression symptom and severity rating scales (questionaires). The Hamilton Depression Rating
Scale (HAM-D) will serve as the primary measure of efficacy, and . Secondary efficacy
endpoints include the Bech Melancholia Scale (sum of items 1, 2, 7, 8, 10, and 13 of the
17-item HAM-D scale), the Quick Inventory of Depressive Symptomatology (QIDS-SR), the
Clinical Global Impression- Global Improvement and Severity of Illness Scale (CGI-I and
CGI-S, respectively), the HAM-D anxiety factor score (sum of items 10, 11, 12, 13, 15 and
17), the Cognitive and Physical Function Questionnaire (CPFQ) and a morning sleep
questionnaire.

Safety and tolerability will be assessed by monitoring adverse events (AEs or side effects),
physical examinations (including vital signs such as blood pressure and heart rate), clinical
laboratory assessments (blood tests), electrical recordings of the heart (electrocardiograms
or ECG's), the Columbia Suicidality Severity Rating Scale (CSSRS), Sexual Function
Questionnaire (SFQ), and weight change.

Blood samples will be taken at different time points to assess blood levels of orvepitant in
patients, allowing the relationship between amount of orvepitant in the body and efficacy to
be studied.

The primary objective of the study is to evaluate the antidepressant efficacy of orvepitant
(30 and 60mg/day) versus placebo (a "sugar pill", with no active ingredients). The secondary
objectives include assessing the safety and tolerability of orvepitant, assessing the profile
of appearance and disappearance of orvepitant in the body (blood) following administration
(i.e., assessing how long the drug remains in the body), and lastly to examine the
relationship between blood levels of the drug and efficacy (i..e, the change in HAM-D total
score relative to what it was before starting the study medication.

Following an initial screening visit, subjects fulfilling the study entrance criteria will
enter a pre-treatment screening phase to permit evaluation of the laboratory and
electrocardiogram assessments and to confirm eligibility for inclusion into the study. This
screening phase will be a minimum of 7 days, but no longer than 21 days. During the screening
period and the treatment phase if the study, if the subject is selected for study entry,
subjects will undergo assessments of their depressive symptoms via a face-to-face interview
as well as via a video-based system (i.e., live subject interview conducted by an off-site
interviewer using a web-based video camera). Upon completion of the screening period,
eligible subjects will be randomly assigned at the baseline visit to one of three treatment
regimens: orvepitant 30mg/day, orvepitant 60mg/day or placebo for a six-week treatment phase.
The chances of receiving each of the three possible treatments will be equal. Orvepitant will
be administered as tablets. Those subjects randomised to receive placebo will receive study
medication identical in appearance to that received by subjects assigned to receive
orvepitant.

During the treatment phase, subjects will be required to return to the clinic at the end of
Weeks 1, 2, 4 and 6. In addition, all subjects will be required to return for a follow-up
visit 14 days after the last dose of study medication. In addition, all subjects with ongoing
adverse events at the 14-day follow-up visit will be required to return for a further
follow-up visit 28 days after the last dose of study medication.

Male and female outpatients between the ages of 18 to 64 years inclusive with a primary
diagnosis of Major Depressive Disorder will be enrolled into this study. A total of
approximately 350 subjects are expected to be enrolled at approximately 30 different study
sites in the U.S. and Canada.

Inclusion Criteria:

- Subjects must have the ability to comprehend the Informed Consent Form.

- Male or female outpatients, aged 18-64, inclusive.

- A primary diagnosis of major depressive disorder, single episode or recurrent.

- Subjects must, in the investigator's opinion and based on the subject's history, have
met depression criteria for at least 8 weeks prior to the Screening Visit.

- Subjects with symptom severity considered to be at least moderate to severe by the
investigator.

- Women of childbearing potential are only eligible IF they commit to consistent and
correct use of an acceptable method of birth control that must be documentation at
each visit

Exclusion Criteria:

- Subjects whose mood-related symptoms are better accounted for by a diagnosis other
than depression; subjects diagnosed with Alzheimer's Disease or other form of
dementia; subjects diagnosed with a current/recent eating disorder such as anorexia
nervosa or bulimia; subjects with a diagnosed history of schizophrenia,
schizoaffective disorder, or Bipolar Disorder.

- Subjects with any history of a significant abnormality of the neurological system
(including dementia and other cognitive disorders or significant head injury) or any
history of seizures (convulsions).

- Subjects have a positive urine test at screening for illegal drug use and/or who have
a history of substance abuse or dependence (alcohol or drugs) within the past 12
months.

- Subjects who are currently receiving regularly scheduled psychotherapy (individual or
group), plan to start psychotherapy during the trial or have received regularly
scheduled psychotherapy during the 12 week period prior to the Screening Visit.

- Subjects who have a history of failing to respond to adequate treatment with an
antidepressant, i..e, failure to improve following administration of at least two
other antidepressants, each given for at least 4 weeks.

- Subjects who, in the investigator's judgement, pose a homicidal or serious suicidal
risk, have made a suicide attempt within the 6 months preceding screening or who have
ever been homicidal.

- Subjects who have received the following treatments for depression in the past:
electroconvulsive therapy (ECT), vagal stimulation, or transcranial magnetic
stimulation (TMS) within the 6 months prior to the Screening Visit.

- Subjects with an unstable medical disorder; or with a disorder that otherwise would
likely interfere with the activity of the study medication (orvepitant).

- Subjects have any screening laboratory abnormality that in the investigator's
judgement is considered to be clinically significant.

- Subjects with an abnormal thyroid test at the Screening Visit. Subjects maintained on
thyroid medication must have normal thyroid levels for a period of at least six months
prior to the Screening Visit.

- Subjects have any screening electrocardiography (ECG) finding that in the
investigator's judgement is considered to be clinically significant.

- Women who have a positive pregnancy test at the Screening Visit, a positive urine
dipstick test at the Baseline (Randomization) Visit, or who are lactating or planning
to become pregnant within the 4 months following the Screen Visit.

- Subjects who have taken other psychoactive drugs within two weeks prior to the
Baseline Visit i.e. at any time during the Screening period. This includes
"over-the-counter" psychoactive medications such as St. John's Wort and SAM-e.

- Subjects who have taken other drugs within 2 weeks prior to the Baseline visit which
the investigator feels may interact with the study medication.

- Subjects who are currently participating in another clinical trial in which the
subject is or will be exposed to an investigational or non-investigational drug or
device, or has done so within the preceding month for studies unrelated to depression,
or 6 months for studies related to depression.

- Subjects who have no contact with an adult on a daily basis. This would exclude
subjects who are not living with at least one other adult or subjects who do not have
an adult who contacts them on a daily basis.