What is the incidence ratio of weight gain with Abilify (aripiprazole)?

Incidence Ratio of Weight Gain with Abilify (Aripiprazole)

Aripiprazole (Abilify) causes clinically significant weight gain (≥7% of body weight) in 8.1% of adults with schizophrenia and 5.2% of pediatric/adolescent patients compared to 3.2% and 1.6% in placebo groups, respectively. 1

Weight Gain Patterns by Population

Adults

• In adults with schizophrenia: 8.1% experience clinically significant weight gain (≥7% of body weight) 1
• In adults with other indications: 2.2% experience clinically significant weight gain 1
• Mean weight change in adults after short-term treatment (21-25 days): +0.3 kg with aripiprazole vs. -0.1 kg with placebo 1
• Mean weight change at 24 weeks: -1.5 kg with aripiprazole vs. -0.2 kg with placebo 1

Pediatric and Adolescent Patients

• In pooled adolescent schizophrenia and other indications: 5.2% experience clinically significant weight gain 1
• Mean weight change with short-term treatment (42-43 days): +1.6 kg with aripiprazole vs. +0.3 kg with placebo 1
• Mean weight change at 24 weeks: +5.8 kg with aripiprazole vs. +1.4 kg with placebo 1
• In long-term treatment (26 weeks): 32.8% of pediatric patients gained ≥7% of their body weight 1

Comparative Weight Gain Data

Aripiprazole generally causes less weight gain compared to other atypical antipsychotics:

• In a 26-week direct comparison study with olanzapine, 14% of aripiprazole-treated patients experienced significant weight gain compared to 37% with olanzapine (p<0.001) 2
• Mean weight change at 26 weeks: -1.37 kg weight loss with aripiprazole vs. +4.23 kg weight gain with olanzapine 2

Formulation Differences

The formulation of aripiprazole may impact weight gain outcomes:

• Oral aripiprazole in early psychosis patients: approximately 11.0 kg (SD=8.2) weight gain over time 3
• Long-acting injectable (LAI) aripiprazole in early psychosis patients: approximately 3.7 kg (SD=2.1) weight gain over time 3
• However, a contradictory study found LAI aripiprazole associated with 7% (6 kg) weight gain at 12 months in young people with early psychosis 4

Age-Related Differences

• Weight gain appears more pronounced in younger patients:
  • Pediatric patients show greater weight gain than adults 1
  • Tolerability is less favorable in younger (10-12 years) than older (≥13 years) subjects 5
  • In a meta-analysis of pediatric studies, aripiprazole caused a mean weight increase of 0.94 kg (95% CI 0.65-1.24) compared to placebo 6

Clinical Implications

• Weight monitoring is essential, particularly in pediatric patients where weight gain should be assessed against normal growth expectations 1
• Weight gain typically occurs early in treatment and may plateau over time
• Aripiprazole has a more favorable weight gain profile compared to many other atypical antipsychotics, particularly olanzapine 2, 6
• Despite being considered relatively weight-neutral compared to other antipsychotics, aripiprazole still poses a significant weight gain risk, especially in young people with early psychosis 3, 4

Metabolic Considerations

• Aripiprazole has less impact on lipid profiles compared to other antipsychotics like olanzapine 2
• The drug shows minimal effects on total cholesterol, fasting triglycerides, and fasting LDL cholesterol compared to placebo 1

Weight gain with aripiprazole should be carefully monitored, particularly in pediatric populations and those receiving oral formulations, as these groups appear to experience more significant weight changes.