Trial medicines

CEQUEL is comparing combination therapy with quetiapine plus lamotrigine with quetiapine monotherapy for treatment of bipolar depression. The trial will also investigate the effect of adding folic acid to the other trial treatments for bipolar depression.

1. Combination treatment with quetiapine and lamotrigine

Quetiapine:  Evidence suggests that quetiapine, an atypical antipsychotic, provides rapid reduction of depressive symptoms but the sedative effects can lead to discontinuation of treatment which may delay recovery or lead to relapse.

Lamotrigine, an anticonvulsant, has been shown to alleviate depression and to be tolerable in the longer-term but the dose has to be built up slowly over several weeks to avoid serious adverse reactions. It may not therefore provide rapid reduction of symptoms.

Combination of quetiapine and lamotrigine: The combination offers the possibility of both rapid relief from acute symptoms and longer-term mood stability.

CEQUEL will compare the relative safety, efficacy and tolerability of the combination of quetiapine and lamotrigine with quetiapine monotherapy.

2. Folic acid as adjunctive treatment to antidepressants

Folic acid: Epidemiological studies suggest that the addition of folic acid (vitamin B9) to other treatments for depression may lead to more rapid reduction in depressive symptoms and a lower risk of relapse.

Subgroup effects:

• There is some evidence that the effect of folic acid on depressive symptoms may depend upon baseline blood levels of two chemicals - folate and homocysteine.
• There is also evidence that the effect of folic acid on depressive symptoms is affected by a person’s genetic make-up.
  

CEQUEL will compare the safety, efficacy and tolerability of folic acid and placebo and will also explore the subgroup effects outlined above.

Page last edited: 22 October 2008