Effectiveness of risperidone ISM in adult patients with acute schizophrenia: an age subgroup analysis from the RESHAPE study

Background

Younger patients (≤35 years), particularly those in early-phase schizophrenia, may derive greater clinical benefit from long‑acting injectable antipsychotics (LAIs), but evidence is limited [1]. The objective of this analysis was to investigate the impact of age on the effectiveness of Risperidone ISM in acutely ill patients hospitalized for a relapse of schizophrenia under routine clinical practice conditions in the RESHAPE study [2].

Methods

RESHAPE is a multicenter, non-interventional study conducted in adult patients with schizophrenia hospitalized due to acute exacerbation and treated with Risperidone ISM under routine clinical practice (NCT05480046). A subanalysis of the RESHAPE study was conducted according to age groups of participants: young (18-31 years), middle-age (31-50 years) and older (>50 years). The effectiveness in these groups was evaluated by using the Clinical Global Impression-Severity (CGI-S) and 6-item Positive and negative Syndrome Scale (PANSS-6) at baseline Visit (BV, first Risperidone ISM injection), Day 8 (FU1), Day 28 after the first injection (FU2) and final visit (FV) 28 days after the second injection (Day 56). Changes from baseline (CFB) to all visits were analyzed using Student’s t-test for both CGI-S and PANSS-6, and ANOVA test was performed to compare the age groups. All statistical tests were two-tailed with alpha=0.05.

Results

275 participants were enrolled in the RESHAPE study. Of them, 22.2%, 47.3% and 30.5% were young, middle-aged and older adults, respectively. Across all age groups, statistically significant improvement (p<0.0001) was observed in the mean (SD) CFB at all follow-up visits in CGI-S and PANSS-6 scores. No statistical differences among the age groups were observed.

	Parameter	BV [Mean (SD)]	FU1 (Day 8) [Mean (SD)]	FU2 (Day 28) [Mean (SD)]	FV (Day 56) [Mean (SD)]
Young adults (18-30 y) [N=61]	CGI-S score CFB in CGI-s PANSS-6 score CFB in PANSS-6	4.72 (1.23) - 21.34 (6.75) -	3.88 (1.24) -0.81 (0.91) p< 0.0001 17.23 (6.24) -4.37 (3.80) p< 0.0001	3.43 (1.10) -1.16 (1.29) p< 0.0001 14.69 (5.79) -6.55 (6.86) p< 0.0001	3.07 (1.32) -1.56 (1.31) p< 0.0001 13.33 (5.96) -7.89 (5.96) p< 0.0001
Middle-aged adults (31-50 y) [N=130]	CGI-S score CFB in CGI-S PANSS-6 score CFB in PANSS-6	4.72 (0.95) - 21.53 (6.15) -	4.06 (1.03) -0.69 (0.88) p< 0.0001 17.91 (5.38) -3.71 (4.30) p< 0.0001	3.52 (1.15) -1.22 (1.18) p< 0.0001 15.15 (5.77) -6.51 (6.04) p< 0.0001	3.16 (1.17) -1.47 (1.35) p< 0.0001 13.38 (5.22) -7.89 (6.36) p< 0.0001
Older adults (>50 y) [N=84]	CGI-S score CFB in CGI-S PANSS-6 score CFB in PANSS-6	4.67 (1.06) - 22.71 (6.34) -	3.93 (1.10) -0.73 (0.94) p< 0.0001 18.75 (5.89) -3.96 (4.63) p< 0.0001	3.52 (1.19) -1.14 (1.10) p< 0.0001 16.58 (5.43) -6.31 (5.18) p< 0.0001	3.34 (1.15) -1.34 (1.15) p< 0.0001 15.52 (5.98) -7.36 (5.82) p< 0.0001

Conclusions

Treatment with the LAI Risperidone ISM showed statistically significant and clinically relevant improvements in effectiveness across all age groups in a real-world hospital setting for acutely exacerbated patients with schizophrenia. Significant reductions in CGI-S and PANSS-6 scores were observed as early as 8 days after the first injection, with comparable effectiveness regardless of the participants’ age.

References

Fu, A.Z., Pesa, J.A., Lakey, S., Benson, C. Healthcare resource utilization and costs before and after long-acting injectable antipsychotic initiation in commercially insured young adults with schizophrenia. BMC Psychiatry. 2022;22(1):250.
Correll, C.U., Rohner, H., Dimalta, S., Göldner, R.S., Assion, H.J., Langner-Timm, S., et al. Risperidone-ISM® effectiveness and tolerability in acute schizophrenia patients hospitalised due to a relapse: results from an international, prospective, non-interventional evaluation (RESHAPE study). World J Biol Psychiatry. 2026;27(4):361-378.