P. Pancheri, L. Tarsitani - Vol. 11, March 2005, Issue 1
Testo Immagini Bibliografia Summary IndiceNuovo approccio alla terapia antipsicotica:
un agonista parziale D2-5HT1A
A new approach to antipsychotic therapy: a D2-5HT1A partial agonist
Introduction
In antipsychotic drug treatment, partial
dopamine agonist activity represents a promising characteristic in view of
the most recent pathophysiological hypotheses of schizophrenia. Aripiprazole
is a new antipsychotic molecule that will soon be marketed in Italy. Its innovative
action profile is characterized by a potent partial agonist activity for D2
and 5-HT1A receptors and by antagonist activity for 5HT2A receptors. The objective
of this paper is to review all available evidence of the pharmacodynamics,
pharmacokinetics, clinical efficacy and safety of aripiprazole.
Methods
Pertinent data were identified through careful MEDLINE search with "aripiprazole"
as a key word, as well as through search between abstracts presented at scientific
congresses.
Results
Aripiprazole has linear pharmacokinetics, is rapidly absorbed and mainly
eliminated through the liver; it shows few pharmacological interactions. Short-term
studies carried out on patients with schizophrenia or schizoaffective disorder
in their acute phase showed superior efficacy with respect to placebo, comparable
efficacy to that of haloperidol and risperidone on positive and negative symptomatology,
and onset of response between the first and the second week of treatment.
The two long-term trials showed aripiprazole to be superior to placebo and
not different from haloperidol in preventing relapse; furthermore, they suggest
aripirprazole to be better than haloperidol in some of the employed outcome
measures. Some data suggest an interesting role of aripirprazole in drug-resistant
schizophrenia and in switching from other treatments.
Studies of bipolar disorder show aripiprazole to be more effective than placebo
and haloperidol in the treatment of manic and mixed symptoms and in the induction
of clinical response. The dimensional profile of aripiprazole conferms its
efficacy on the positive and negative dimension of schizophrenia, suggest
a promising action on the "depression", "excitement/aggressiveness"
and "cognitive" dimensions. Aripiprazole shows a favorable general
safety profile, with few extrapyramidal effects, nonsignificant body weight
increases, no induction of hyperprolactinemia and few metabolic effects.
Conclusions
On the basis of available data, aripiprazole is provided with efficacy
at least equal to that of other antipsychotic drugs, but is endowed with a
better safety profile and is very well tolerated.