The researchers in this trial want to learn more about the drug Laif® 900 in preventing the return of signs and symptoms of depressions (also called relapse) in patients suffering from moderate depression episodes. The study drug Laif® 900 is based on Hypericumextract made from the plant St. John wort. Patients will be accepted to take part in the study if they have 20-24 points on the Hamilton Depression Rating Scale (HAM-D) which is a questionnaire helping the doctor to rate the severity of the depression and includes questions on patient's mood, sleep difficulties, agitation, anxiety and weight loss. About 400 patients will be enrolled into the first part of the study and will be treated for 12 weeks with Laif® 900 capsule once daily. Only patients with an improved HAM-D score by 50% will stay in the study and continue with the second part of the study which will last for 24 weeks.

In this second part of the study patients will receive either Laif® 900 capsule once daily or an inactive tablet (placebo). Neither the treating doctor nor the patient will know which patient receives the Laif® 900 or placebo. At the end of the study the researcher will assess the effectiveness of the study drug in prevention relapse of depression episodes and will also have more information on the safety of the study drug.

Inclusion Criteria:

Study Phase 1:

• Age 18-70 years
• Diagnosis according to DSM-IV-TR: 296.32: Outpatients with a mediocre depressive episode requiring treatment for recurrent major depression
• At least 5 of the following symptoms must persist for 2 weeks, with at least one of the main symptoms:
• Depressed mood (main symptom)
• Loss of interest or pleasure (main symptom)
• Significant weight loss without diet or weight gain
• Increased sleep or insomnia
• Psychomotor restlessness or slowing down
• Excessive, inappropriate guilt or feelings of worthlessness on almost every day
• Subjective or observable diminished ability to think and to decide
• Fatigue and loss of energy
• Suicidal thoughts and / or actions

Study Phase 2:

• Phase 1 responders (= Phase 1 patients who have at least a 50% decrease in the HAMD-17 total score after 12 weeks of Laif® 900 therapy).

Exclusion Criteria: General (phase 1 and phase 2)

• Unable to work and patients cared for according to the BtG (working group "Stay") and "Medical Measures")
• Simple mourning reaction
• Clinically relevant laboratory abnormalities due to severe organ and systemic diseases
• Taking immunosuppressants (eg after organ transplants)
• Taking oral contraceptives with low levels of hormones (estrogen ≤ 50 μg, micropillus)
• Thyroid dysfunction (patients with non-euthyroid TSH levels)
• Known intolerance to the test medication
• Known photosensitivity
• Diabetes mellitus type I and II requiring treatment
• Unstable hypertension
• Pregnancy or breastfeeding
• Cancer and AIDS patients (HIV-positive)
• Alcohol, drug or drug abuse in the last 6 months
• Coadministration with coumarin-type anticoagulants
• History of epilepsy
• Melanoma
• Specific psychotherapy in the last 2 months and during the clinical trial
• Participation in a clinical trial within the last 30 days
• Simultaneous participation in another clinical trial
• Compliance and protocol management are not guaranteed by language problems

Availability of this study's data will be determined according to Bayer's commitment to the EFPIA/PhRMA "Principles for responsible clinical trial data sharing". This pertains to scope, timepoint and process of data access. As such, Bayer commits to sharing upon request from qualified researchers patient-level clinical trial data, study-level clinical trial data, and protocols from clinical trials in patients for medicines and indications approved in the US and EU as necessary for conducting legitimate research. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014. Interested researchers can use www.clinicalstudydatarequest.com to request access to anonymized patient-level data and supporting documents from clinical studies to conduct research. Information on the Bayer criteria for listing studies and other relevant information is provided in the Study sponsors section of the portal.