lithium versus cariprazine in the acute phase treatment of bipolar depression (duag9)

Conditions: Depression, Bipolar

Summary: the goal is to study the effect of lithium compared to cariprazine in patients with depression in a bipolar disease. the main question it aims to answer is: difference in change between the two groups from baseline to after 8 weeks treatment on hamilton ratings scale for depression, 6-item version (hds-6) participants will be randomized to treatment with either lithium or cariprazin. * will meet for interview and ratings 4 times during study period. * in two meetings, there will be made blood samples and ecg. at one meeting also a urine sample. * will be contacted for telephone interviews at 6 occasions.

the primary aim is to investigate whether cariprazine is superior to lithium or vice versa in the acute treatment of patients with bipolar type 1 or 2 in a current depressive episode measured as change on the hamilton depression scale, 6 item version (hds-6) from baseline to 8 weeks of treatment. secondarily, we aimed at comparing the two study medications on various other clinically relevant variables. these include depressive and manic symptomatology, sleep patterns, general well-being, cognitive function, social functioning and suicidal ideation.

Eligibility criteria:
inclusion criteria: * a diagnosis of bipolar disorder, type 1 or type 2, and a current episode of depression according to dsm-5 * severity of depression: a score of at least 21 on the self-reported major depression inventory (mdi). * no start or dose increase of psychotropic medication (except for benzodiazepines and benzodiazepine-like drugs (zopiclone, zolpidem, and melatonin)) in the two weeks prior to inclusion. * no new start of formalized psychotherapy sessions, excluding psychoeducation, during the 4 weeks prior to inclusion. * age criteria: subjects must be at least 18 years old and below 65 at the time of randomization. * the duration of the current depressive episode must be between 4 and 52 weeks as judged by the investigator at the time of randomization. * clinical uncertainty regarding which of the alternatives, cariprazine and lithium, would be the better choice in the specific case. * female participants should be sterile or non-fertile or, in case of being fertile, they must have a negative pregnancy test and use safe anticonception. * signed document of informed consent. exclusion criteria: * prior or ongoing acute treatment of a depressive episode lasting \> 14 days with either lithium or cariprazine as judged by the investigator. * ect within the current depressive episode. * a score of mas \> 6. * a diagnosis of dementia. * high risk of non-adherence at the investigator's discretion. * not understanding the danish language as judged by the investigator * psychiatric coercion in the form of forced admission or detainment or sentence to forensic psychiatric care. * presence of clinically relevant delusions, hallucinations or other psychotic symptoms as judged by the investigator. * suicidality according to c-ssrs with a positive response to question 4 or 5 or upon investigator's discretion. * medical conditions like cancer, kidney failure, epilepsy, deep brain stimulation device, or other medical conditions interfering with study the outcome and safety as judged by investigator's discretion. * current harmful use or dependency of alcohol or drugs according to dsm-5. * known allergy to any of the substances in the study medication.