Seroquel Study Results for Treating Mania and Depression in Bipolar Disorder Types I and II
AstraZeneca manufactures the drug Seroquel (quetiapine fumarate) and announced results of a 509 patient study at last week’s American Psychiatric Association meeting.
Seroquel is currently FDA approved for treating bipolar disorder I acute mania and schizophrenia. The announced study results looked at Seroquel to treat depression in bipolar types I and II patients, to confirm results of a prior study.
Seroquel is being positioned as treatment to both stabilize mood and relieve depression, to eliminate the need to use a mood stabilizing drug and an antidepressant. Having one less pill to take may help patients with bipolar disorder adhere to (stick to) their drug therapy.
Late last year, the company submitted a supplemental supplemental New Drug Application (sNDA) with the FDA for Seroquel in treating depression in bipolar disorder patients.
What I found interesting is the high response rate of the placebo (sugar pill) arms. At the end of the 2 month study (8 weeks):
60% of patients who took Seroquel at 300 mg/day responded
58% of patients who took Seroquel at 600 mg/day responded
45% of patients who took placebo responded.
It looks like a higher dose didn’t give a higher response rate, although higher doses of drug usually comes with higher percentage of side effects.
Caution: Seroquel should not be used in patients with dementia-related psychosis (usually elderly patients), and has also been associated with changes in body metabolism including hyperglycemia and ketoacidosis.
Mental Health Clinical Studies Lacking Key Information
In Psychiatric Times March 2002 Vol. XIX Issue 3, Deborah Lott’s article, “Are Studies Misguiding the Choice of First-Line Treatments?” describes how Boston University’s psychologist Drew Western and colleagues reviewed 34 studies on psychotherapies in peer-reviewed journals, and is now suggesting that some of the first-line treatments may have been based on studies that weren’t as scientifically sound.
The 34 studies Western and colleagues reviewed were published in an 8-year span (1990-1998). These studies included panic disorder (17 studies), generalized anxiety disorder (GAD, 5 studies) and depression (12). Studies that did not meet minimum criteria for randomized control trials were not considered.
Some of the observations by Western and colleagues:
- Long-term follow-up to look at lasting effects of treatment were often missing (beyond, 12, 18, or 24 months)
- Some studies did not report why certain patients were not included (also known as “exclusion rates”)
- Panic disorder treatment showed the most impressive results where 63% of patients showed improvement
- 54% of patients with depression showed improvement but the analysis of existing study data did not show long-term effects
- 52% of generalized anxiety disorder patients showed improvement but no data was published for long-term follow-up
Why does this matter? Well, most physicians base their prescribing and treatment decisions on published studies. When many studies don’t look at long-term effects, what can we say about the effects of certain drugs used in the long term of as mental health treatment?
Of course, we also want to be very cautious of conclusions drawn from “meta-analyses” like this one. One of the drawbacks and criticisms in meta-analyses is that you may be comparing apples and oranges. You can’t pool a collection of studies for depression together and treat them like one clinical study - because there are too many different factors to consider. And conclusions drawn may not be accurate.
One thing that we can be certain though - long-term follow-up is needed in clinical studies. This is the only way we can look at how well some of these treatments work in the long-term.
This discussion is extremely long. Those who are interested can read it on Psychiatric Times.