US-based Forest Laboratories and Hungarian pharmaceutical firm Gedeon Richter have reported positive topline results from a Phase IIb trial of its investigational drug 'cariprazine' as adjunctive treatment in adult patients with major depressive disorder (MDD).
The international, multicentre, randomised, double-blind, placebo-controlled, parallel-group, flexible-dose, eight-week trial assessed the efficacy, safety, and tolerability of cariprazine in MDD patients who have showed an inadequate response to antidepressant therapy (ADT).
The Phase IIb trial consisted of three treatment groups, cariprazine 1.0mg-2.0mg/day + ADT and cariprazine 2.0mg-4.5mg/day + ADT, and placebo + ADT.
The company said that the group who received cariprazine 2.0mg-4.5mg/day + ADT showed significant improvement in the Montgomery-Asberg Depression Rating Scale (MADRS) total score versus placebo at eight weeks, the primary endpoint.
Forest Laboratories chief medical officer and EVP of Drug Development and Research Marco Taglietti said: "Forest is committed to addressing the therapeutic needs of people living with MDD as part of our growing mental health portfolio, and we are excited at the prospect to one day offer a new treatment option for appropriate patients seeking an alternative treatment to manage the condition."
Eligible patients in the trial were those who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria for MDD, had a minimum score of 22 on the MADRS scale, and had an ongoing inadequate response to ADT.
After a seven to 14 day screening and washout period, a total of 819 patients between 18 and 65 years of age were given one of three treatment groups followed by a one-week safety follow-up period.
The company said that primary endpoint was defined as change from baseline to end of week 8 in the MADRS total score.
The most common adverse events observed across both cariprazine dose groups were akathisia, nausea, insomnia, somnolence, and fatigue.
Cariprazine, an orally active, potent dopamine D3-preferring D3/D2 receptor partial agonist atypical antipsychotic, has a low affinity at other receptor sites such as 5-HT2C, muscarinic, and adrenergic receptor sites.
The drug is protected by a composition-of-matter patent that expires in 2027 without patent term extension and it is being developed for the treatment of schizophrenia and bipolar mania in adults.