Farmeco 2018;20(1)13-24.html
Farmeconomia. Health economics and therapeutic pathways 2019; 20(1): 13-24
https://doi.org/10.7175/fe.v20i1.1393
Original Research
Effectiveness of Long-Acting Injectable Antipsychotics in Schizophrenia: A Literature Review and Bayesian Meta-Analysis Informing Economic Considerations
Orietta Zaniolo 1, Gianni Ghetti 1, Massimiliano Povero 1, Lorenzo Pradelli 1
1 AdRes – Health Economics & Outcome Research, Turin
Abstract
BACKGROUND: Although the use of long-acting injectable antipsychotics (LAIs) is considered an important option in the management of schizophrenia two recent meta-analysis, which aimed to compare LAIs vs oral antipsychotics (OAPs) in terms of relapse rate, showed discordant results.
AIM: To investigate factors affecting the efficacy of antipsychotics in terms of relapse prevention in the real-world and to estimate the management cost of an episode of relapse.
METHODS: We conducted a literature search using MEDLINE/PubMed with the aim to extract efficacy, effectiveness and adherence data of LAIs and OAPs. The primary outcome was the relative risk (RR) of relapse between two strategies. The extracted RR were included in a series of Bayesian statistical models based on the starting hypotheses. The RR rates obtained from the meta-analysis have been used as input for an economic evaluation of the total costs associated with the management of the patient with schizophrenia from the Italian NHS perspective.
RESULTS: The literature search identified 34 studies which met the inclusion criteria and were analyzed. According to the model that best explains the data, in the real-world setting the effectiveness with LAIs is greater than with OAPs, with a more pronounced effect for SGAs than for FGAs. Taking into account generation, route and frequency of administration, the RR decreased with lower administration frequency, with SGA LAI administered once every 90 days which is associated with the greatest reduction in the risk of relapse (-85%). When the results of the meta-analysis are used to feed an economic evaluation the results show that the SGA administered every 90 days is the strategy with the least expected cumulative cost both at 1 (€ 3,509) and 5 years (€ 19,690).
CONCLUSION: SGA LAIs administered every 90 days seems to be the best option for the treatment of patient with schizophrenia from both the clinical and economic perspectives.
Keywords
Long-acting injectable antipsychotics; Schizophrenia; Relapse; Italy
Corresponding author
Lorenzo Pradelli
l.pradelli@adreshe.com
Received: 20 June 2018
Accepted: 18 January 2019
Published: 31 January 2019
Introduction
Despite there have been significant pharmacological progresses and improvements in individual and community assistance, schizophrenia remains a disabling, chronic disease with alternating periods of remission and relapse. Since each subsequent relapse exacerbates the clinical deterioration of the patient, with consequent worsening of symptoms, progressive cognitive impairment, functioning deterioration, and reduced quality of life, one of the major goals of schizophrenia treatment is to prevent or delay relapse [1-5].
Long-acting injectable antipsychotics (LAIs) were introduced in clinical practice in the 1960s with the aim of overcoming the limits associated with oral antipsychotics (OAPs) in terms of treatment adherence and pharmacokinetics profile [2-7].
Although the use of LAIs is considered an important option, in particular for patients with adherence problems [2,3,5,8], two recent meta-analyzes [9,10], which aimed to compare LAIs vs OAPs in terms of relapse rate, showed discordant results between randomized clinical trials (RCTs) and mirror-image studies.
The first meta-analysis [10] included only RCTs lasting more than 6 months, which compared LAIs and OAPs. The primary outcome was the relapse rate at the longest study time point; secondary outcomes included the relapse rate at specific time points (3, 6, 12, 18, and 24 months), all-cause discontinuation, discontinuation due to adverse events, drug inefficacy, hospitalization and non-adherence. A total of 21 RCTs were included in the analysis and the results showed that, when pooled together, LAIs did not reduce relapse compared with OAPs. In particular, pooled LAIs only showed trend-level superiority over OAPs in preventing hospitalization (RR = 0.88; 95% CI: 0.78-1.02; p = 0.09) with a gradient related to the frequency of administration (longer intervals of administration were associated with a greater reduction of relapse rate) and pharmacological class (relapse rate with SGA was lower than with FGA).
Since the patients enrolled in RCTs are generally different from those in real-world studies in terms of adherence rate and illness severity, the second meta-analysis conducted by Kishimoto et al. [9] was based on 25 mirror-image studies, which better reflect the real-world setting. The study included mirror-image studies that compared period ≥ 6 months with OAPs and ≥ 6 months with LAIs in adults with schizophrenia and that reported information about hospitalization or relapse-related data. The primary outcomes were hospitalization risk and the total number of hospitalizations, while secondary outcomes included total hospitalization days and length of stay. The results of this meta-analysis show a statistically significant superiority of LAIs over OAPs in preventing hospitalization (RR = 0.43, 95% CI: 0.35-0.53; p < 0.001) and decreasing the number of hospitalizations (RR = 0.38; 95% CI: 0.28-0.51; p < 0.001).
In the light of these results we conducted a comprehensive literature review and meta-analyzed the retrieved data by use of a Bayesian hierarchical model, with the aim to investigate factors affecting the efficacy of antipsychotics in terms of relapse prevention in the real-world (effectiveness). The results of the meta-analysis have been used as input for an economic evaluation of the total costs associated with the management of the patient with schizophrenia from the Italian National Health System (NHS) perspective. Mean cumulative total cost per patient at 1 and 5 years, was calculated by antipsychotic treatment (first or second generation and administration frequency) and cost items (antipsychotic treatment and relapse management).
Methods and input data have been reviewed and approved by an Italian expert board (see Acknowledgements).
Methods
Starting from the assumption that the antipsychotics effectiveness is a function of both their pharmacological and pharmacodynamics characteristics, on one side, and their use in real-world setting, on the other, a meta-analysis has been performed to test the following hypotheses:
In a real-world setting LAIs are associated with better adherence compared to OAPs;
In an experimental setting (RCT) a LAI and the same OAP have similar efficacy and adherence while in the real-world a net increase in the efficacy of LAI can be noted;
This phenomenon has a gradient and it becomes more evident when the administration is less frequent.
Literature Search and Inclusion Criteria
We conducted a literature search using MEDLINE/PubMed (last access May 18, 2017) with the aim to extract efficacy, effectiveness and adherence data of LAIs and OAPs.
The search strings (one for the search of efficacy/effectiveness data and one for the search of adherence data) have been designed on the basis of the PICOS schema (Table I), as recommended by the PRISMA guidelines [11].
Two independent investigators conducted the literature search; the revision and the selection of the studies were performed on the basis of title/abstract and then of the full-text. The electronic search through MEDLINE was supplemented by manual check of reference lists of included studies. Any disagreements were resolved by discussion or by the intervention of a third investigator.
PICOS component
Inclusion criteria
Exclusion criteria
Participants
Adults with schizophrenia
Other mental disorder
Acute phase
Drug resistance
Observational cohort studies < 50 patients
Intervention
Oral or long-acting injectable monotherapy with risperidone, paliperidone, aripiprazole, olanzapine, haloperidol, fluphenazine, zuclopentixol
Any other treatment
Comparators
All (head to head, placebo, other formulation, other or none)
-
Outcome
Primary: relapse rate
Secondary: treatment adherence
Absence of adherence or relapse outcome
Study design
Efficacy: interventional studies (RCT, nRCT, Uncontrolled Clinical Trial – UCT)
Effectiveness: observational studies (cohort longitudinal retrospective or prospective studies)
Adherence: observational studies (cohort longitudinal retrospective or prospective studies)
Review/meta-analyses
Case-report/case series
Preclinical studies
Other
Out of objective (scope): evaluation of the effect of discontinuation therapy, switch, on-top/augmentation strategies; methodological and pharmacokinetics studies
Post-hoc or subgroup analyzes
Unavailability of full-text
Table I. Inclusion and exclusion criteria
Data Extraction and Data Analysis
The primary outcome was the relative risk (RR) of relapse between two strategies. Therefore, we selected all the studies that compared two strategies differing in terms of active ingredient and/or administration route and/or inter-administration interval and extracted the adjusted relative risk (RR) from the text. When the relative risk was not reported, we estimated it from reported data as the ratio between absolute rates.
For RCTs we relied on the efficiency of randomization in minimizing the risk of bias, and took no further action, while for observational studies, this was done only in case of cohorts matched on risk factors for relapse, or statistically equivalent in terms of baseline characteristics. This implies that any observational study on mismatched cohorts did not contribute to the estimation of relative treatment effects.
The extracted relative risks were included in a series of Bayesian statistical models based on the starting hypotheses. In order to identify the hypothesis that best suited the data, three model sets based on alternative assumptions on the influence of administration were tested: route only, administration frequency only, or both.
For the effect of administration frequency on risk of relapse, proportional (RR depends on the ratio of frequencies) and additive (RR depends on the difference of frequencies) specifications were evaluated.
Finally, all model versions were evaluated with and without considering the generation of the AP (FGA vs. SGA).
For the relative effectiveness and economic outcome predictions, inference was based on the best model. This was identified by means of the Bayesian Information Criterion (BIC), which allows selecting the best model basing on goodness-of-fit and parsimony, with lower values indicating better performance.
The secondary outcome was the adherence, but the qualitative analysis of adherence data revealed extremely high heterogeneity in the measurement methods, in the outcomes and in the elaborations, in addition to poor reliability of the data for oral drugs. All these factors were judged to have a too high potential for bias to obtain a reliable result. For this reason adherence data were excluded from the quantitative analysis.
Economic Evaluation
The relative relapse rates obtained from the meta-analysis have been used to feed an economic evaluation of the total costs associated with the antipsychotic treatment over a time horizon of 1 and 5 years.
OAPs (€)
LAIs (€)
2-weekly
3-weekly
Monthly
3-Monthly
FGA
7.9
-
14.8
10.5
-
SGA
30.2
269.6
-
287.3
287.3
Table II. Weighted average ex-factory prices
FGA OAP = haloperidol; SGA OAP = paliperidone, risperidone, olanzapine, aripiprazole; SGA 2-weekly = olanzapine, risperidone; FGA 3-weekly = fluphenazine; FGA monthly = haloperidol; SGA monthly = paliperidone, olanzapine, aripiprazole; SGA 3-monthly = assumed equal to SGA monthly
Since the analysis was performed from the Italian NHS perspective, only direct costs were considered. Drug acquisition costs were calculated taking into account the treatment mix reported by IQVIA for Italy in 2017 [12], their maximum acquisition cost for the NHS, the adherence rate and the time horizon.
Weighted average ex-factory prices for each category are reported in Table II. They have been estimated starting from ex-factory price for drugs in class H or A included in the PHT list [13] and retail price for drugs in class A non-included in the PHT list [13], after weighting the contribution of the different dose levels to the total sales of a single brand, and then weighing brands belonging to the same categories by their respective patient shares, as reported by sales data in 2017 [12].
The adherence rate was estimated (for costing purposes only) at 50% for OAPs, which is an average from the literature data. Applying the odds ratios estimated by Pillon et al. [14], the adherence rate for first generation (71%) and second generation (82%) LAIs was calculated.
The relapse management cost was calculated from the relapse rate by class and administration frequency obtained from the meta-analysis and the cost of managing an episode of relapse.
According to Expert opinion the cost of an episode of relapse was not only derived from the Diagnosis Related Group (DRG) tariff, which does not encompass the entire relapse management pathway, but it was calculated taking into account both hospitalization and the subsequent stay in residential facilities. In order to better represent the Italian context, the mean cost between Lazio, Lombardy, and Tuscany was used in the economic evaluation. The cost considered by the experts comprises the hospitalization for the acute phase for 10-15 days (proxied with the regional tariffs) and the following rehabilitation in a dedicated institution for a mean of 30 days: the resulting mean cost per relapse is € 10,500.
In the 5-year scenario every relapse increases the subsequent relapse rate by 20% [15,16].
Figure 1. Flowchart of literature search
Results
Search and Study Characteristics
The literature search identified 546 studies, plus 39 studies added through manual check, for a total of 585 studies. Of these, 368 studies were excluded after the screening by title and abstract and 217 were fully inspected. Finally, 34 studies (20 RCTs) met the inclusion criteria and were analyzed (Figure 1). The details of the studies included are presented in Table III [17-50].
Common results of all tested models indicate that:
In real-world setting, the effectiveness is greater with LAIs than with orals– this effect is more pronounced for SGAs than for FGAs, while the route has no statistically significant effect under experimental conditions;
In real-world settings the effectiveness significantly increases with decreasing administration frequency;
There are high probabilities (80-95% in the best fitting models) that the intrinsic efficacy of SGAs is greater than that of FGAs.
The model best explaining the data was the one that comprises both the effect of route and frequency of administration (additive effect) and that considers a class effect (FGAs vs. SGAs) for both intrinsic efficacy and administration route effect (Table IV).
According to this model:
In the real world setting, a LAI reduces the risk of relapse, compared to the same AP given by the oral route, by 20% (RR = 0.8) if it belongs to the first generation, and by almost 50% (RR = 0.53) if a SGA;
In the real world setting, the risk of relapse is reduced by 10% (RR = 0.9) for each additional week of inter-dose interval;
Second generation agents reduce the risk of relapse by almost 20% (RR = 0.79) when compared to FGAs of equivalent route and frequency of administration.
Reference
Comparators
Patients (n.)
Relative efficacy/effectiveness
Data extracted
Observational studies [17-30]
Baser, 2015
PAL 30 vs. SGA OAPs
335 vs. 335
0.623
Ratio between absolute rates in propensity score matching
Bitter, 2013
RIS 14 vs. ARI oral
1095 vs. 601
0.640
Ratio between absolute rates in propensity score matching
Bitter, 2013
RIS 14 vs. OLA oral
1095 vs. 1633
0.767
Ratio between absolute rates in propensity score matching
Bitter, 2013
RIS 14 vs. RIS oral
1095 vs. 2480
0.387
Ratio between absolute rates in propensity score matching
Grimaldi-Bensouda, 2012
RIS 14 vs. OAPs
400 vs. 784
0.490
Adjusted RR from text
Guo, 2011
OLA oral vs. ARI oral
149 vs. 132
0.947
Ratio between absolute rates
Joshi, 2016
PAL 30 vs. RIS 14
499 vs. 499
0.720
Adjusted OR from text
Lafeuille, 2015
PAL 30 vs. OAPs
374 vs. 32475
0.750
HR from text
Marcus, 2015
FLU 14-42 vs. OAPs
45 vs. 3428
0.870
Adjusted OR from text
Marcus, 2015
ALO 28 vs. OAPs
112 vs. 3428
0.910
Adjusted OR from text
Marcus, 2015
RIS 14 vs. OAPs
81 vs. 3428
0.670
Adjusted OR from text
Marcus, 2015
PAL 30 vs. OAPs
102 vs. 3428
0.530
Adjusted OR from text
Morrato, 2015
PAL 30 vs. SGA OAPs
201 vs. 595
0.860
Adjusted OR from text
Ren, 2011
RIS 14 vs. OAPs
924
0.743
Ratio between absolute rates
Schreiner, 2014
RIS 14 vs. SGA OAPs
426 vs. 490
0.654
Ratio between absolute rates
Tiihonen, 2006
OLA oral vs. ALO oral
822 vs. 107
0.540
Adjusted RR from text
Tiihonen, 2006
RIS oral vs. ALO oral
651 vs. 107
0.890
Adjusted RR from text
Tiihonen, 2011
RIS 14 vs. RIS oral
51 vs. 411
0.570
Adjusted HR from text
Tiihonen, 2011
ZUC 14 vs. ZUC oral
30 vs. 6
0.490
Adjusted HR from text
Tiihonen, 2011
ALO 28 vs. ALO oral
6 vs. 9
0.120
Adjusted HR from text
Tiihonen, 2017
RIS 14 vs. RIS oral
3021 vs. 7016
0.859
Ratio between adjusted HR vs. no treatment from text
Tiihonen, 2017
ZUC 14 vs. ZUC oral
4083 vs. 3425
0.791
Ratio between adjusted HR vs. no treatment from text
Tiihonen, 2017
OLA 14 vs. OLA oral
400 vs. 1173
0.921
Ratio between adjusted HR vs. no treatment from text
Tiihonen, 2017
ALO 28 vs. ALO oral
1632 vs. 3348
0.790
Ratio between adjusted HR vs. no treatment from text
Voss, 2015
PAL 30 vs. OAPs
109 vs. 109
0.540
HR from text
RCT [31-50]
Alphs, 2015
PAL 30 vs. OAPs
226 vs. 218
0.681
Ratio between absolute rates
Buckley, 2014
RIS 14 vs. OAPs
146 vs. 150
1.285
Ratio between absolute rates
Carpenter, 1999
FLU 14 vs. FLU 42
25 vs. 25
0.763
Ratio between absolute rates
Csernansky, 2002
ALO oral vs. RIS oral
188 vs. 177
1.930
RR from text
Detke, 2014
OLA 28 vs. OLA oral
264 vs. 260
1.086
Ratio between absolute rates
Fleischhacker, 2014
ARI 28 vs. ARI oral
265 vs. 266
0.985
Ratio between absolute rates
Glick, 2002
OLA oral vs. ALO oral
541 vs. 158
0.828
Ratio between absolute rates
Hogarty, 1979
FLU 14 vs. FLU oral
27 vs. 25
0.862
Ratio between absolute rates
Ishigooka, 2015
ARI 28 vs. ARI oral
228 vs. 227
0.920
Ratio between absolute rates
Kane, 2009
OLA oral vs. ARI oral
281 vs. 285
0.985
Ratio between absolute rates
Kane, 2010
OLA 14 vs. OLA oral
281 vs. 322
1.500
Adjusted HR from text
Kane, 2010
OLA 28 vs. OLA oral
318 vs. 322
1.400
Adjusted HR from text
Kane, 2010
OLA 14 vs. OLA 28
281 vs. 318
1.000
Adjusted HR from text
Keks, 2007
RIS 14 vs. OLA oral
247 vs. 300
1.170
Ratio between absolute rates
Kim, 2008
RIS 14 vs. RIS oral
22 vs. 28
0.307
Ratio between absolute rates
Lieberman, 2005
OLA oral vs. RIS oral
330 vs. 333
0.575
Ratio between absolute rates
Malla, 2016
RIS 14 vs. OAPs
42 vs. 35
1.894
Ratio between absolute rates
McEvoy, 2014
PAL 30 vs. ALO 28
145 vs. 145
1.294
Ratio between absolute rates
Rosenheck, 2011
RIS 14 vs. OAPs
187 vs. 182
0.870
Adjusted HR from text
Savitz, 2016
PAL 90 vs. PAL 30
483 vs. 512
0.870
HR from text
Schooler, 1980
FLU 21 vs. FLU oral
107 vs. 107
0.668
Ratio between absolute rates
Schooler, 2005
RIS oral vs. ALO oral
197 vs. 203
0.864
Ratio between absolute rates
Table III. Details of the studies included in the meta-analysis
ALO = haloperidol; ARI = aripiprazole; FLU = fluphenazine; OAP = oral antipsychotics; OLA = olanzapine; PAL = paliperidone; RIS = risperidone; SGA = second generation antipsychotics; ZUC = zuclopentixol
Treatment effect
FGA: LAIs vs. OAPs
SGA: LAI vs. OAPs
SGA vs. FGA
+7 days1
RR [95% CI]
0.80 [0.69-0.93]
0.53 [0.48-0.58]
0.79 [0.58-1.09]
0.90 [0.80-1.00]
Credibility2 (%)
99.8
100
93.4
97.2
Table IV. Best model results (real-world)
1 Each additional 7 days of inter-dose interval
2 Posterior probability of superiority, measured as percentage of iterations with RR < 1
Figure 2 shows the relative risks (vs. FG OAP, taken as reference) for all considered combinations of generation, route, and frequency of administration inferred by the model. As can be seen, relapse rate decreased with lower administration frequency, and the greatest reduction in the risk of relapse is expected with the use of a SGA LAI administered once every 90 days, associated with an estimated RR of 16%, i.e. a reduction of 84% in the frequency of relapse, compared to the use of an oral, first generation, antipsychotic agent.
Figure 2. Relapse rate reduction vs oral FGA according to class and administration frequency
Credibility of results (i.e. posterior probability of superiority, measured as percentage of iterations with RR < 1 - data not shown) resulted close to certainty (98-100%) for the comparison of any LAI vs. any OAP, while there is substantial uncertainty in the comparison of oral SGAs versus first generation LAIs.
Economic Evaluation
The average (95% CrI) cumulative 1 year and 5 year cost for the management of a patient with schizophrenia estimated by the model for the available strategies are shown in Table V.
The data indicate that the strategy with the least expected cumulative cost is SGA administered every three months, already at one year, and more so in the medium term (5 years), with 91% (data not shown) chances of being the least costly strategy (Table VI).
Observing the contribution of the single cost items to the total (Figure 3), it can be seen how the component related to the drug acquisition becomes more prevalent moving from the least to the most effective treatments, and how this trend becomes more evident with longer time horizons.
Administration frequency
Total cost per patient (€)
1 year
5 years
FGA
SGA
FGA
SGA
Daily
6,086 [4,112-8,472]
4,753 [3,425-6,332]
45,180 [30,480-62,950]
34,930 [25,060-46,670]
2-weekly
NA
5,085 [4,285-6,064]
NA
31,370 [25,590-38,570]
3-weekly
4,493 [2,793-6,697]
NA
33130 [20460-49520]
NA
Monthly
4,022 [2,380-6,196]
4,786 [4,085-5,643]
29710 [17480-45870]
28,720 [23,670-34,930]
3-monthly
NA
3,795 [3,045-5,275]
NA
21,270 [15,940-32,350]
Table V. Mean [95% CrI] cumulative total cost per patient at 1 and 5 years, by antipsychotic treatment
Administration frequency
Probability SGA 90-day less costly (mean delta) vs.
FGA
SGA
FGA
SGA
After 1 year
After 5 years
Daily
98% (2,291 €)
87% (958 €)
100% (23,910 €)
97% (13,660 €)
2-weekly
96% (1,290 €)
96% (10,100 €)
3-weekly
77% (698 €)
97% (11,860 €)
Monthly
58% (227 €)
97% (991 €)
93% (8,440 €)
97% (7,450 €)
Table VI. Probability that the cumulative total cost per patient of alternative strategies is higher than SGA 90-day at 1 and 5 years, and their mean cost increase
Figure 3. Mean cumulative total cost per patient at 1 and 5 years, by antipsychotic treatment and cost items
Discussion
Long-acting injectable antipsychotics (LAIs) were introduced in the treatment of schizophrenia with the aim of improving treatment adherence and pharmacokinetics profile associated with OAPs.
Our meta-analysis, which aimed to investigate factors affecting the efficacy of antipsychotics in terms of relapse prevention in the real-world (effectiveness), shows that in the real-world setting the effectiveness with LAIs is greater than with OAPs, with a more pronounced effect for SGAs than for FGAs. In particular, a LAI reduced the risk of relapse by 20% and 50%, as compared to the same AP given by oral route and belonging to the first and the second generation, respectively. Furthermore, in the real-world setting the effectiveness significantly increases with decreasing administration frequency, with a relative reduction in the risk of relapse equal to 10% for each additional week of inter-dose interval. Taking into account generation, route and frequency of administration our results show that, taking FGA OAP as reference, the relapse rate decreased with lower administration frequency, with SGA LAI administered once every 90 days which is associated with the greatest reduction in the risk of relapse (-84%). As shown in Table III, only one RCT that compares 90-day LAI was included in the meta-analysis [48]. This trial involved 1016 patients who were randomly assigned to 90-day paliperidone or 30-day paliperidone and showed noninferiority of the 3-month formulation in terms of relapse rate. The results demonstrated the noninferiority of the 3-monthly administration in terms of relapse rate and the mITT analysis showed that the nominal hazard ratio for a patients switching from 90-day (n = 483) to 30-day (n = 512) formulation was 0.87 (95% CI: 0.56-1.34).
When the results of the meta-analysis are used to feed an economic evaluation, in order to estimate the management cost of an episode of relapse, the results show that the SGA administered every 90 days is the strategy with the least expected cumulative cost at 1 and 5 years (€ 3,795 and € 21,270, respectively).
Observing the composition of the single cost items (relapse management and drug cost) it can be seen that the cost for relapse management decreases moving from the daily administration to less frequent administration schedules. Furthermore, even if the component related to the drug acquisition becomes more prevalent moving from the least to the most effective treatment, the clinical advantage in terms of relapse prevention compensates the drug cost, resulting in a lower total expenditure.
Our conclusions are in line with a recent systematic review, which aimed to investigate the economic impact of schizophrenia on the healthcare system in Europe and to identify the most important cost driver in the management of schizophrenia [51]. According to Kovacs et al. the component related to the hospital stay represents the major direct cost of schizophrenia, accounting for 27% to 92% of total direct medical costs, depending on the country considered. Among the suggestions given by the Authors in order to reduce the economic burden associated with schizophrenia and to improve the allocation of financial resources, there are the reduction of the number of hospitalizations and the improvement of persistence and adherence in antipsychotic therapy [51].
At the light of these results, it can be said that more efforts are needed in order to improve the management of patients with schizophrenia and to enhance identification of patients who can benefit most from the treatment with LAIs achieving better clinical and economic outcomes.
The main limitation of our study is the inclusion in the meta-analysis of only one trial that compares 90-day vs. 30-day administration, however, due to the structure of the model, comparing strategies with differing administration frequency, provide information about the effect of the extension of the administration interval.
Conclusion
Since one of the major goal of the treatment of schizophrenia is to prevent/delay relapse, at the light of our results SGA LAIs administered every 90 days seems to be the best option from both the clinical and economic perspectives.
Acknowledgements
We would like to thank the advisory board members for their expert opinions:
Luca Degli Esposti, CliCon S.r.l. – Health Economics & Outcome Research, Bologna
Roberta Di Turi, Direttore Farmacia Ospedaliera Presidio Ospedaliero Giovan Battista Grassi, Roma
Giuseppe Ducci, Direttore del Dipartimento di Salute Mentale U.O.C. Prevenzione Interventi Precoci Salute Mentale U.O.C. S.P.D.C. S. Filippo Neri, Roma
Edvige Facchi, Direttore UFSAM Grosseto. AUSL Toscana SudEst
Andrea Fagiolini, Professore di Psichiatria dell’Università di Siena
Antonio Lora, Direttore Dipartimento Salute mentale, ASST Lecco
Claudio Mencacci, Direttore Dipartimento Neuroscienze e Salute mentale P.O. Fatebenefratelli e Oftalmico, Milano
Marzia Mensurati, Responsabile Farmacia Territoriale ASL Roma 5
Gaetana Muserra, Direttore S.C. Farmacia P.O. Fatebenefratelli e Oftalmico, Milano
Giuseppe Nicolò, Direttore Dipartimento di Salute Mentale ASL Roma 5
Mauro Percudani, Direttore Dipartimento di Salute Mentale e delle Dipendenze, ASST Grande Ospedale Metropolitano Niguarda, Milano
Paolo Rossi Prodi, Direttore della UO Salute Mentale. AUSL Toscana Centro
Funding
The study was made possible by an unconditional grant from Janssen-Cilag SpA.
Conflict of interest
OZ, GG, and MP are employees of Adres, which has received project funding by Janssen-Cilag SpA for the conduct of the study.
LP is co-owner and employee of Adres, which has received project funding by Janssen-Cilag SpA for the conduct of the study. LP is an editorial member of Farmeconomia. Health Economics and Therapeutic Pathways.
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