Although not licensed for acute bipolar depression, lamotrigine has evidence for efficacy in trials and its use is recommended in guidelines. So far there had been no prospective health economic evaluation of its use.
Costutility analysis of the CEQUEL trial comparing quetiapine plus lamotrigine vs quetiapine monotherapy (and folic acid vs placebo in an addon factorial design) for patients with bipolar depression (n = 201) from the health and social care perspective. Differences in costs together with qualityadjusted life years (QALYs) between the groups were assessed over 52 weeks using a regressionbased approach.
Healthrelated quality of life improved substantially for all randomization groups during followup with no significant difference in QALYs between any of the comparisons (mean adjusted QALY difference: lamotrigine vs placebo 0.001 (95% CI: 0.05 to 0.05), folic acid vs placebo 0.002 (95% CI: 0.05 to 0.05)). While medication costs in the lamotrigine group were higher than in the placebo group (£647, P < 0.001), mental health community/outpatient costs were significantly lower (£670, P < 0.001). Mean total costs were similar in the groups (£180, P = 0.913).
Lamotrigine improved clinical ratings in bipolar depression compared with placebo. This differential effect was not detected using the EQ5D3L. The additional cost of lamotrigine was balanced by significant savings in some other medical costs which made its use cost neutral to the health service. Compared to placebo, folic acid produced neither clinical nor significant health economic benefits. The study supports the use of lamotrigine in combination with other drugs to treat bipolar depression.