OBJECTIVES : Treatment patterns can vary substantially in patients with major depressive disorder (MDD) as they progress through multiple lines of therapy (LOT). This descriptive study examined treatment patterns in patients with MDD by the LOT using a large US-based claims database.

METHODS : Using the Truven MarketScan Research Database, we conducted a retrospective analysis of patients (≥18 years) diagnosed with MDD (1/1/2013-9/30/2016), who received a new antidepressant or atypical antipsychotic for MDD treatment during a pre-specified index window (01/01/2014-09/30/2016). Treatment combinations were assessed for patients grouped by number of LOT received (up to 6+) with any combination of antidepressants, atypical antipsychotics, anxiolytics, or sleep medications during the index treatment window.

RESULTS : Overall, 500,502 patients were prescribed over 1,100 different unique combinations of antidepressant/atypical-antipsychotic medications. Although monotherapy (76%, median 177 days) was the most common index treatment approach, combination therapies (24%, median 214 days) were also used early in the patient treatment journey and became more common with increasing LOT (13% to 39% as LOT increased from 1^st to 6^th+) Of patients receiving pharmacotherapy, those with more treatment experience were more likely to remain on any pharmacotherapy at 12 months (discontinuation rates decreased from 32% to 4% as LOT increased from 1st to 6th+), while the ratio of patients who persisted on a given treatment increased by 7% from 1st to 2nd line treatment and subsequently decreased for all remaining lines.

CONCLUSIONS : Our findings indicate that pharmacotherapy treatment strategies for MDD are inconsistent across treatment lines and are often augmented with other antidepressants, anxiolytics, or sleep medications. The increasing diversity of combination therapies with incremental LOT highlights the challenges that exist in following MDD treatment guidelines.