Paroxetine or Quetiapine in Addition to Mood Stabilizers in Bipolar Depression

INTERVENTION: Trade Name: DAPAROX*28CPR RIV 20MG PVC/PE/ Pharmaceutical Form: Film‐coated tablet INN or Proposed INN: Paroxetine Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 20‐ Trade Name: SEROQUEL*60CPR RIV 100MG Pharmaceutical Form: Film‐coated tablet INN or Proposed INN: Quetiapine Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 100‐ CONDITION: Major Depressive Episode in Bipolar Disorder ; MedDRA version: 9.1 Level: LLT Classification code 10004908 Term: Bipolar affective disorder PRIMARY OUTCOME: Main Objective: 1.To evaluate the efficacy of paroxetine or quetiapine addition on depressive symptoms in patients with a bipolar disorder and a major depressive episode during therapy with mood stabilizer (lithium or valproate) Primary end point(s): 1.Mean reduction of the HAM‐D scale score; percentage of subjects who obtain a response (HAM‐D ≤ 50% baseline) and/or remission (HAM‐D ≤ 7) ; 2.Percentage of subjects with a YMRS score ≥ 12 at the end of the study; 3.Changes in SF‐36 scores at 4 and 12 weeks Secondary Objective: 1.To evaluate the risk of switch into mania during the treatment with paroxetine or quetiapine in addition to a mood stabilizer.; 2.To evaluate change in quality of life associated to paroxetine or quetiapine in patients with bipolar disorder and a current major depressive episode during the treatment with a mood stabilizer (lithium or valproate) INCLUSION CRITERIA: 1. Age ≥ 18 years 2. Read understood and signed the informed consent 3. Diagnosis of Bipolar Disorder, Major Depressive Episode diagnosed by means of MINI 5.0.0. 4. Treatment with lithium or valproate in previous 2 months, with lithium levels 0.6‐1.2 mEq/L or valproate levels 50‐130 ug/ml at baseline 5.HAM‐D ≥ 18 6.YMRS ≤ 12 Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range