Conditions: Major Depressive Disorder Dysthymia Disorder
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 1
Healthy volunteers: no

Brief summary:
The objective of the study is to compare the efficacy of intranasal oxytocin versus intranasal placebo to improve depression symptoms in patients with Major Depressive Disorder (MDD) or Dysthymia Disorder.

Detailed description:
Depression patients treated with even the best currently available antidepressant drugs continue to experience significant symptoms. There is a strong need for better treatments including treatments that can safely be given adjunctively with concurrent antidepressants in order to improve overall efficacy of treatment.

Oxytocin is a neurohypophyseal peptide best known for its role as a neurohormone involved in parturition and lactation. In addition to these well established peripheral effects, there is a compelling body of converging evidence indicating that oxytocin plays a critical role in the regulation of a number of diverse centrally-mediated behavioral and cognitive processes that are highly relevant to mood regulation and mood disorders, including social attachment (Argiolas and Gessa 1990; McCarthy and Aaltemus 1997).

Each subject will be enrolled for a 8 week treatment period after a screening phase. Study procedure involves weekly clinic visits as an outpatient. Twenty patients will be randomly assigned to either 40 IU oxytocin twice daily or vehicle placebo. After 4 weeks, treatments will be crossed over such that subjects that received oxytocin will receive placebo and vice versa. The study ratio is 1:1. Dose of oxytocin is based upon previous studies in humans showing improvement in psychiatric populations related changes in behavior and brain function (Kosfeld et al, 2005; Kirsch 2005; Heinrich M 2003).

The total study duration for each individual subject will be approximately 9 weeks, which includes up to 31-day screening period, a baseline (randomization) visit, four week treatment period, 1 week washout, baseline 2 visit, and four weeks cross over treatment.

Arms:
arm 1: 20 IU of intranasal oxytocin twice per day for the first week, 40 IU of intranasal oxytocin twice per day for the following 3 weeks, one week wash out, 4 week placebo trial. arm 2: Four week placebo trial, one week wash out, 20 IU of intranasal oxytocin twice per day for one week, 40 IU of intranasal oxytocin twice per day for 3 weeks.

Interventions: intervention 1: Oxytocin intervention 2: Placebo
Intervention descriptions: intervention 1: 20 IU BID for one week, followed by 40 IU BID for 3 weeks. intervention 2: 20 IU BID for one week, followed by 40 IU BID for 3 weeks.

Protocol document: