Recent Research on Risperidone

An important paper was published in America last week that looks at the efficacy of an antipsychotic medicine that is sometimes used in treating the most severe cases of OCD.

We asked David Veale, one of the Charity’s trustees, to comment

“The paper describes a controlled trial in which 100 people with OCD who had received a SSRI medication for at least 3 months and had moderate OCD symptoms were randomized to receive either (A) risperidone (an antipsychotic) or (B) Pill placebo or (C) Cognitive Behavioural Therapy over 17 sessions. At the end of 8 weeks, the CBT was significantly superior to either risperidone or placebo. There was no difference between those who received risperidone or placebo. It was unfortunate that the study will not be included in the NICE Evidence Update that is due this month as the study was published too late to be included.

Americans generally tend to be more enthusiastic about medication. In the UK, the NICE guidelines (2005) recommend that CBT is used as the treatment for people with OCD for mild to moderate OCD. A SSRI is recommended if a person does not want CBT or something to be added to CBT if a person is not making sufficient progress. Other options include more intensive CBT. Drugs like risperidone are not recommended unless a person with OCD is severe and has received at least 2 trials of SSRIs and of CBT.

Antipsychyotics were recommended by NICE because other published trials showed some minor benefit in OCD. However this recent study throw this into question. Some experts in OCD still think that antipsychotics like risperidone may be effective in severe treatment refractory OCD as the population in this trial had never received CBT and had had just one trial of a SSRI – however this is just expert opinion and we don’t know who they may benefit. The problem with drugs such as risperidone is the possible side effects such as weight gain, emotional numbing and loss of libido. What we don’t know is whether there are unpublished trials of antipsychotics, which have negative findings – it’s probably unlikely that there are unpublished trials in OCD for antipsychotics as they are not licensed for OCD and are a very small market compared to their use in schizophrenia. However I recommend Ben Goldacre’s book on Bad Pharma to understand the impact of negative trials and other problems with the pharmaceutical industry.

Whilst discussing antipsychotics, it’s worth mentioning a recent paper by Diniz et al (2011) who reported another trial in which they randomly allocated OCD patients who failed to respond to a SSRI (fluoxetine) by adding either clomipramine (an older drug used in OCD) or quetiapine (an antipsychotic like risperidone). Those who received clomipramine with to fluoxetine did better than those who received quetiapine. Others have reported using high doses of a SSRI (e.g fluoxetine 80mg or more) to be helpful in people with OCD who were resistant to lower doses.

Thus for all these reasons I don’t personally like to recommend antipsychotics even in severe treatment refractory OCD because the possible benefits are minimal and side-effects can be a significant problem. They are of course justified in schizophrenia but they need to be closely monitored in terms of the possible side effects. Thus, in my view, antipsychotics are only ever justified when a person with OCD is severely agitated and in the short term.

At present the Highly Specialized Service for severe treatment refractory OCD (which is funded centrally rather locally) requires a person to be in the severe range of symptoms and have failed at least two sets of CBT, two trials of SSRIs or clomipramine and one trial of “augmentation” of a SSRI. Augmentation could be (1) an antipsychotic (like risperidone), which as I have described has weak evidence (2) combining SSRI with clomipramine or (3) high dose of the SSRI. If I was a patient, and had failed CBT and SSRI (each twice) then I would want more intensive CBT. If I wanted to try another medication then I think I would opt for either the combination of a SSRI with clomipramine or a high dose SSRI.”