Efficacy and safety of aripiprazole once-monthly versus oral aripiprazole in Chinese patients with acute schizophrenia: a multicenter, randomized, double-blind, non-inferiority study

Long-Acting Injectable Second-Generation Antipsychotics vs Placebo and Their Oral Formulations in Acute Schizophrenia: A Systematic Review and Meta-Analysis of Randomized-Controlled-Trials

BACKGROUND AND HYPOTHESIS

Long-acting injectable antipsychotic drugs (LAIs) are mainly used for relapse prevention but could also be advantageous for acutely ill patients with schizophrenia.

STUDY DESIGN

We conducted a systematic review and meta-analysis of randomized-controlled-trials (RCTs) comparing the second-generation long-acting injectable antipsychotics (SGA-LAIs) olanzapine, risperidone, paliperidone, and aripiprazole with placebo or their oral counterparts in acutely ill patients with schizophrenia. We analyzed 23 efficacy and tolerability outcomes, with the primary outcome being overall symptoms of schizophrenia. The results were obtained through random effects, pairwise meta-analyses, and subgroup tests. The study quality was assessed using the Cochrane-Risk-of-Bias-Tool version-1.

STUDY RESULTS

Sixty-six studies with 16 457 participants were included in the analysis. Eleven studies compared second-generation long-acting injectable antipsychotics (SGA-LAIs) with a placebo, 54 compared second-generation oral antipsychotics (SGA-orals) with a placebo, and one compared an SGA-LAI (aripiprazole) with its oral formulation. All 4 SGA-LAIs reduced overall symptoms more than placebo, with mean standardized differences of -0.66 (95% CI: -0.90; -0.43) for olanzapine, -0.64 (-0.80; -0.48) for aripiprazole, -0.62 (-0.76; -0.48) for risperidone and -0.42 (-0.53; -0.31) for paliperidone. The side-effect profiles of the LAIs corresponded to the patterns known from the oral formulations. In subgroup tests compared to placebo, some side effects were less pronounced under LAIs than under their oral formulations.

CONCLUSIONS

SGA-LAIs effectively treat acute schizophrenia. Some side effects may be less frequent than under oral drugs, but due to the indirect nature of the comparisons, this finding must be confirmed by RCTs comparing LAIs and orals head-to-head.

Long-Acting Injectable Antipsychotic Treatment for Schizophrenia in Asian Population: A Scoping Review

Evidence of comparative benefits of long-acting injectable (LAI) antipsychotics in Asian patients with schizophrenia has been inconsistent. This scoping review aimed to synthesize the current evidence in the past ten years and provide an overview of efficacy, safety, treatment adherence, patient attitudes, and healthcare resource utilization of LAI in this population. A systematic search was conducted with a pre-defined search strategy in six electronic databases including Chinese National Knowledge Infrastructure (CNKI), Wanfang, PubMed, Embase, CINAHL, and PsycArticles. A total of 46 studies were included, including 15 cohort studies, 13 single-arm trials, 10 randomized controlled trials, four mirror-image studies, three cross-sectional studies, and one controlled clinical trial. Paliperidone palmitate once-monthly injection (27/46) and risperidone LAI (14/46) were the most frequently investigated LAIs. Compared with oral antipsychotic medications (OAMs), LAIs demonstrated a lower rate of relapse/hospitalization and comparable improvement in efficacy. Adverse events (AEs) were similar between LAIs and OAMs, although types and incidence varied. Significant reduction in the length of hospitalization and number of outpatient visits/inpatient admission was observed after initiation of LAIs. These findings suggest that LAI demonstrated comparable efficacy and safety among Asian populations with schizophrenia in comparison to OAMs. Better adherence and lower relapse were observed in patients receiving LAIs from published evidence. Future research is warranted to better understand the comprehensive performance of LAI in specific population or context.

Enhanced Solubility and Stability of Aripiprazole in Binary and Ternary Inclusion Complexes Using Hydroxy Propyl Beta Cyclodextrin (HPβCD) and L-Arginine

The low water solubility of an active pharmaceutical ingredient (aripiprazole) is one of the most critical challenges in pharmaceutical research and development. This antipsychotic drug has an inadequate therapeutic impact because of its minimal and idiosyncratic oral bioavailability to treat schizophrenia. The main objective of this study was to improve the solubility and stability of the antipsychotic drug aripiprazole (ARP) via forming binary as well as ternary inclusion complexes with hydroxypropyl-β-cyclodextrin (HPβCD) and L-Arginine (LA) as solubility enhancers. Physical mixing and lyophilization were used in different molar ratios. The developed formulations were analyzed by saturation solubility analysis, and dissolution studies were performed using the pedal method. The formulations were characterized by FTIR, XRD, DSC, SEM, and TGA. The results showcased that the addition of HPβCD and LA inclusion complexes enhanced the stability, in contrast to the binary formulations and ternary formulations prepared by physical mixing and solvent evaporation. Ternary formulation HLY47 improved dissolution rates by six times in simulated gastric fluid (SGF). However, the effect of LA on the solubility enhancement was concentration-dependent and showed optimal enhancement at the ratio of 1:1:0.27. FTIR spectra showed the bond shifting, which confirmed the formation of new complexes. The surface morphology of complexes in SEM studies showed the rough surface of lyophilization and solvent evaporation products, while physical mixing revealed a comparatively crystalline surface. The exothermic peaks in DSC diffractograms showed diminished peaks previously observed in the diffractogram of pure drug and LA. Lyophilized ternary complexes displayed significantly enhanced thermal stability, as observed from the thermograms of TGA. In conclusion, it was observed that the preparation method and a specific drug-to-polymer and amino acid ratio are critical for achieving high drug solubility and stability. These complexes seem to be promising candidates for novel drug delivery systems development.

Differences in autonomic nervous system activity between long-acting injectable aripiprazole and oral aripiprazole in schizophrenia

BACKGROUND

Distinct oral atypical antipsychotics have different effects on autonomic nervous system (ANS) activity. Among them, oral aripiprazole has been linked to dysfunction of the ANS in schizophrenia. Long-acting injectable aripiprazole is a major treatment option for schizophrenia, but the effect of the aripiprazole formulation on ANS activity remains unclear. In this study, we compared ANS activity between oral aripiprazole and aripiprazole once-monthly (AOM) in schizophrenia.

METHODS

Of the 122 patients with schizophrenia who participated in this study, 72 received oral aripiprazole and 50 received AOM as monotherapy. We used power spectral analysis of heart rate variability to assess ANS activity.

RESULTS

Patients who received oral aripiprazole showed significantly diminished sympathetic nervous activity compared with those who received AOM. Multiple regression analysis revealed that the aripiprazole formulation significantly influenced sympathetic nervous activity.

CONCLUSION

Compared with oral aripiprazole, AOM appears to have fewer adverse effects, such as sympathetic nervous dysfunction.