New therapeutics – Cannabidiol
The psychopharmacological treatment of psychoses of the schizophrenia spectrum is sincerely affected by an unsatisfactory efficacy for some patients. Beyond that the existing pharmaceuticals show a large number of side effects. Therefore, the development of more effective and/ or less side-effect prone alternatives is essential.
In recent years we have conducted several studies based on our findings regarding the role of the endogenous cannabinoid system in schizophrenia. We have completed the first controlled, double-blind randomized exploratory clinical trial on the safety and efficacy of cannabidiol in acute episodes of schizophrenia and we have performed a placebo-controlled double-blind study in first-episode patients with acute schizophrenia. In both studies, cannabidiol led to a significant decrease of psychotic symptoms in the acute stage of this disorder. In addition, cannabidiol displayed a mark-edly superior side effect profile compared to the standard antipsychotic. The mentioned side effect profile was even comparable to placebo.
Although these initial results seem very promising, the existing data is not yet sufficient to designate cannabidiol as a prooven antipsychotic. Several larger clinical trials are necessary to do so and we are about to conduct the first of them already. As more results concerning the efficacy of cannabidiol in the treatment of psychosis and schizophrenia will become available we will let you know here.
At the present stage of its development, we strictly do NOT recommend to use cannabidiol as an antipsychotic under any circumstances other than in controlled clinical trial conditions. In particular no data is available for safety and efficacy of maintenance treatment using cannabidiol yet. In addition, no drug-drug-interaction data prooving safety of combined treatment with cannabidiol and existing antipsychotics has been reported so far in humans.
This research is supported by the Stanley Medical Research Institute of the Theodore and Vada Stanley Foundation, USA (Grant IDs 00-093, 05T-678 and 08TGF-1257 to FML), the European Commission (EU FP7 HEALTH-F2-2010-242114 - OPTiMiSE) and the German Federal Ministry of Education and Research (BMBF – ESPRIT Network, FKZ: 01EE1407A).
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