# The time has come for revising the rules of clozapine blood monitoring in Europe. A joint expert statement from the European Clozapine Task Force

Helene Verdoux, Robert A Bittner, Alkomiet Hasan, Mishal Qubad, Elias Wagner, Alexis Lepetit, Manuel Arrojo-Romero, Christian Bachmann, Marieke Beex-Oosterhuis, Jan Bogers, et al.

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## To cite this version:

Helene Verdoux, Robert A Bittner, Alkomiet Hasan, Mishal Qubad, Elias Wagner, et al. The time has come for revising the rules of clozapine blood monitoring in Europe. A joint expert statement from the European Clozapine Task Force. European Psychiatry, 2025, 68 (1), pp.e17. 10.1192/j.eurpsy.2024.1816. [hal-05022682](https://hal.science/hal-05022682v1)

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Submitted on 7 Apr 2025

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**Cite this article:** Verdoux H, Bittner RA, Hasan A, Qubad M, Wagner E, Lepetit A, Arrojo-Romero M, Bachmann C, Beex-Oosterhuis M, Bogers J, Celofiga A, Cohen D, de Berardis D, de Hert M, de Las Cuevas C, Ebdrup BH, Fountoulakis KN, Guinart D, Keating D, Kopeček M, Lally J, Lazáry J, Luykx JJ, Maronas Amigo O, Molden E, Nielsen J, O'Donoghue B, Oswald P, Radulescu FS, Rohde C, Sagud M, Sanz EJ, Šimunović Filipčić I, Sommer IE, Taipale H, Tiihonen J, Tuppurainen H, Veerman S, Wilkowska A, Spina E, Schulte P (2025). The time has come for revising the rules of clozapine blood monitoring in Europe. A joint expert statement from the European Clozapine Task Force. *European Psychiatry*, **68**(1), e17, 1–5
https://doi.org/10.1192/j.eurpsy.2024.1816

Received: 16 December 2024

Accepted: 30 December 2024

**Keywords:**

blood monitoring; clozapine; regulation;
treatment-resistant schizophrenia

**Corresponding author:**

Hélène Verdoux;

Email: helene.verdoux@u-bordeaux.fr

© The Author(s), 2025. Published by Cambridge
University Press on behalf of European
Psychiatric Association. This is an Open Access
article, distributed under the terms of the
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creativecommons.org/licenses/by/4.0), which
permits unrestricted re-use, distribution and
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properly cited.

# The time has come for revising the rules of clozapine blood monitoring in Europe. A joint expert statement from the European Clozapine Task Force

Hélène Verdoux<fnref n="1" /> ID, Robert A. Bittner² ID, Alkomiet Hasan³,⁴ ID, Mishal Qubad² ID,
Elias Wagner³,⁵ ID, Alexis Lepetit⁶,⁷,⁸ ID, Manuel Arrojo-Romero⁹ ID,
Christian Bachmann¹⁰ ID, Marieke Beex-Oosterhuis¹¹ ID, Jan Bogers¹² ID,
Andreja Celofiga¹³ ID, Dan Cohen¹⁴,¹⁵ ID, Domenico de Berardis¹⁶ ID,
Marc de Hert¹⁷,¹⁸,¹⁹,²⁰ ID, Carlos de Las Cuevas²¹ ID, Bjørn H. Ebdrup²²,²³ ID,
Konstantinos N. Fountoulakis²⁴ ID, Daniel Guinart²⁵,²⁶,²⁷ ID, Dolores Keating²⁸ ID,
Miloslav Kopeček²⁹,³⁰ ID, John Lally³¹,³²,³³ ID, Judit Lazáry³⁴ ID,
Jurjen J. Luykx³⁵,³⁶,³⁷,³⁸ ID, Olalla Maronas Amigo³⁹,⁴⁰,⁴¹,⁴² ID, Espen Molden⁴³,⁴⁴ ID,
Jimmi Nielsen⁴⁵ ID, Brian O'Donoghue⁴⁶,⁴⁷ ID, Pierre Oswald⁴⁸ ID,
Flavian S. Radulescu⁴⁹ ID, Christopher Rohde⁵⁰,⁵¹ ID, Marina Sagud⁵²,⁵³ ID,
Emilio J. Sanz⁵⁴,⁵⁵ ID, Ivona Šimunović Filipčić⁵⁶,⁵⁷ ID, Iris E. Sommer⁵⁸ ID,
Heidi Taipale⁵⁹,⁶⁰,⁶¹ ID, Jari Tiihonen⁵⁹,⁶⁰,⁶² ID, Heli Tuppurainen⁵⁹ ID,
Selene Veerman⁶³,⁶⁴ ID, Alina Wilkowska⁶⁵ ID,
Edoardo Spina⁶⁶ ID and Peter Schulte⁶⁴,⁶⁷ ID

<footnote n="1">¹French Clozapine Task Force, University of Bordeaux, Inserm, Bordeaux Population Health Research Center, Bordeaux, France; ²Goethe University Frankfurt, University Hospital, Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Frankfurt am Main, Germany; ³Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, University of Augsburg, Augsburg, Germany; ⁴DZPG (German Center for Mental Health), Partner Site, Munich/ Augsburg, Germany; ⁵Evidence-based Psychiatry and Psychotherapy, Faculty of Medicine, University of Augsburg, Augsburg, Germany; ⁶French Clozapine Task Force; ACPPA Group, Francheville, France; ⁷Hospices Civils de Lyon, Hôpital des Charpennes, Villeurbanne, France; ⁸Institut des Sciences Cognitives Marc Jeannerod, CNRS, Bron, France; ⁹Department of Psychiatry, Complejo Hospitalario Universitario de Santiago, Santiago de Compostela, Spain; ¹⁰Department of Child and Adolescent Psychiatry, Ulm University, Ulm, Germany; ¹¹Department of Hospital Pharmacy, Albert Schweitzer Hospital, Dordrecht, The Netherlands; ¹²Mental Health Organization Rivierduinen, Leiden, The Netherlands; ¹³Department of Psychiatry, University Medical Centre Maribor, Maribor, Slovenia; ¹⁴Dutch Clozapine Collaboration Group, Alkmaar, The Netherlands; ¹⁵Esdege-Reigersdaal, Heerhugowaard, The Netherlands; ¹⁶NHS, Department of Mental Health, G. Mazzini Hospital, Teramo, Italy; ¹⁷University Psychiatric Center Katholieke Universiteit Leuven, Kortenberg, Belgium; ¹⁸Department of Neurosciences, Centre for Clinical Psychiatry, Katholieke Universiteit Leuven, Leuven, Belgium; ¹⁹Leuven Brain Institute, Katholieke Universiteit Leuven, Leuven, Belgium; ²⁰Antwerp Health Law and Ethics Chair, University of Antwerp, Antwerp, Belgium; ²¹Department of Internal Medicine, Dermatology and Psychiatry, School of Medicine, University of La Laguna, Canary Islands, Spain; ²²Center for Neuropsychiatric Schizophrenia Research (CNSR), Mental Health Center, Glostrup, Copenhagen University Hospital – Mental Health Services CPH, Copenhagen, Denmark; ²³Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; ²⁴³rd Department of Psychiatry, Division of Neurosciences, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece; ²⁵Institut de Salut Mental, Hospital del Mar, Barcelona, Spain; ²⁶Programa Recerca en Salut Mental, Hospital del Mar Research Institute, CIBERSAM, Barcelona, Spain; ²⁷The Donald and Barbara Zucker School of Medicine, Northwell Health, New York, NY, USA; ²⁸Saint John of God Hospital, Stillorgan, Co. Dublin, Dublin, Ireland; ²⁹National Institute of Mental Health, Klecany, Czech Republic; ³⁰Department of Psychiatry, Third Faculty of Medicine, Charles University, Prague, Czech Republic; ³¹Department of Psychiatry, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland; ³²Department of Psychiatry, St Vincent's Hospital Fairview, Dublin, Ireland; ³³Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, UK; ³⁴Nyirő Gyula National Institute of Psychiatry and Addictions, Budapest, Hungary; ³⁵Department of Psychiatry, Amsterdam UMC, Amsterdam, The Netherlands; ³⁶GGZ inGeest Mental Health Care, Amsterdam, The Netherlands; ³⁷Amsterdam Neuroscience (Mood, Anxiety, Psychosis, Stress & Sleep program) and Amsterdam Public Health (Mental Health program) Research Institutes, Amsterdam, The Netherlands; ³⁸Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience Maastricht University Medical Center, Maastricht, The Netherlands; ³⁹Pharmacogenomics and Drug Discovery (GenDeM), Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Spain; ⁴⁰Genomic Medicine Group, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain; ⁴¹Centre for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain; ⁴²Galician Public Foundation of Genomic Medicine (FPGMX), Galician Healthcare Service (SERGAS), Santiago de Compostela, Spain; ⁴³Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy,</footnote>
University of Oslo, Oslo, Norway; ⁴⁴Center for Psychopharmacology, Diakonhjemmet Hospital, Oslo, Norway; ⁴⁵Mental Health Centre Glostrup, Copenhagen University Hospital, Copenhagen, Denmark; ⁴⁶Department of Psychiatry, University College Dublin, Dublin, Ireland; ⁴⁷Department of Psychiatry, St Vincent's University Hospital, Dublin, Ireland; ⁴⁸Department of Psychiatry, Hôpital Universitaire de Bruxelles, Bruxelles, Belgium; ⁴⁹Center for Drug Sciences, Faculty of Pharmacy, University of Medicine and Pharmacy Carol Davila, Bucharest, Romania; ⁵⁰Department of Affective Disorders, Aarhus University, Hospital - Psychiatry, Aarhus, Denmark; ⁵¹Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; ⁵²Department of Psychiatry, School of Medicine, University of Zagreb, Zagreb, Croatia; ⁵³Department for Psychiatry and Psychological Medicine, University Hospital Center Zagreb, Zagreb, Croatia; ⁵⁴Department of Physical Medicine and Pharmacology, School of Medicine, Universidad de La Laguna, Canary Islands, Spain; ⁵⁵Hospital Universitario de Canarias, Tenerife, Spain; ⁵⁶Department of Psychiatry and Psychological Medicine, University Hospital Centre Zagreb, Zagreb, Croatia; ⁵⁷Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; ⁵⁸Department of Neuroscience, and Department of Psychiatry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; ⁵⁹Department of Forensic Psychiatry, University of Eastern Finland, Niuvanniemi Hospital, Kuopio, Finland; ⁶⁰Department of Clinical Neuroscience, Karolinska Institutet, and Center for Psychiatry Research, Stockholm City Council, Stockholm, Sweden; ⁶¹School of Pharmacy, University of Eastern Finland, Kuopio, Finland; ⁶²Neuroscience Center, University of Helsinki, Helsinki, Finland; ⁶³Mental Health Services Noord-Holland-Noord, Schagen, The Netherlands; ⁶⁴Dutch Clozapine Collaboration Group, Alkmaar, The Netherlands; ⁶⁵Department of Psychiatry, Medical University of Gdańsk, Gdańsk, Poland; ⁶⁶Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy and ⁶⁷Mental Health Services Noord-Holland-Noord, Alkmaar, The Netherlands

## Abstract

The European Clozapine Task Force is a group of psychiatrists and pharmacologists practicing in 18 countries under European Medicines Agency (EMA) regulation, who are deeply concerned about the underuse of clozapine in European countries. Although clozapine is the most effective antipsychotic for people with treatment-resistant schizophrenia, a large proportion of them do not have access to this treatment. Concerns about clozapine-induced agranulocytosis and stringent blood monitoring rules are major barriers to clozapine prescribing and use. There is a growing body of evidence that the incidence of clozapine-induced agranulocytosis is very low after the first year of treatment. Maintaining lifelong monthly blood monitoring after this period contributes to unjustified discontinuation of clozapine. We leverage recent and replicated evidence on the long-term safety of clozapine to call for the revision and updating of the EMA's blood monitoring rules, thus aiming to overcome this major barrier to clozapine prescribing and use. We believe the time has come for relaxing the rules without increasing the risks for people using clozapine in Europe.

## Introduction

Shortly after the introduction of clozapine in the 70s, several cases of fatal agranulocytosis in Finland led to its market withdrawal in almost all countries. Following the study by Kane et al. in people with treatment-resistant schizophrenia (TRS) [1], clozapine was reintroduced with strict blood monitoring rules to detect incident agranulocytosis, estimated at 1–2% lifetime. More than 35 years later, these rules have not been revised in most countries [2]. Under current European Medicines Agency (EMA) regulation, white blood cell count (WBC) and absolute neutrophil count (ANC) monitoring is required weekly for the first 18 weeks after initiation of treatment and then monthly for the duration of treatment. For many patients, this can mean decades of monthly blood sampling.

Clozapine remains the only approved antipsychotic for TRS with superior efficacy and effectiveness for several endpoints, such as suicide, psychotic symptoms, relapse, rehospitalization, medication adherence, aggression, or substance use. Clozapine use is also associated with reduced all-cause, suicide, and cardiovascular mortality. While TRS occurs in about one-third of schizophrenia patients, only a minority of them are prescribed this medication [3], which represents a missed opportunity for these people, as their chances of recovery are much less favorable without clozapine [3–7].

The need for continued blood tests “for life” is a significant barrier to clozapine initiation and maintenance treatment increasing the risk of premature discontinuation [8, 9]. From the prescriber’s perspective, the most common barriers to clozapine initiation are related to the institutional complexity of mandatory blood monitoring and an overestimated users’ poor adherence to this monitoring [9]. Prescribers’ overestimation of agranulocytosis risk also contributes to under-monitoring of other adverse drug reactions with higher lethality including myocarditis, pneumonia, or ileus [10].

Blood monitoring also comes at a cost. In addition to the direct costs of blood tests, monitoring is time-consuming for laboratories and pharmacies. It requires complex organizational adaptations to guarantee continuity of care, particularly at a time when medical and paramedical staffing levels are low. A cost-effectiveness analysis compared several blood monitoring strategies in a theoretical cohort of 100,000 people treated with clozapine [10]. While the « no monitoring » strategy was the most cost-effective, no difference was found regarding quality-adjusted life-year gained compared to the other modalities, irrespective of the stringency of blood monitoring rules.

## Low risk of agranulocytosis after the first year of treatment

Recent studies have confirmed that the risk window for clozapine-related agranulocytosis is mostly limited to the first months of treatment. A meta-analysis of 108 studies (1983–2017, 448,647 clozapine users) found a 3.8% incidence of mild neutropenia (≤ 1.5 × 10⁹ per L), a 1.3% incidence of moderate neutropenia (≤ 1.0 × 10⁹ per L) and a 0.9% of severe neutropenia, commonly referred to as agranulocytosis (≤ 0.5 × 10⁹ per L) (0.7% when only high-quality studies were considered) [5]. The agranulocytosis fatality rate was one death for 7,700 clozapine users. The agranulocytosis prevalence was identical in studies conducted before and after the introduction of blood monitoring in 1990. In most cases (75%), mild neutropenia did not progress to severe neutropenia. Most cases of agranulocytosis occurred in the first few months of treatment: 38% in the first month, 56% within two months, 84% within the first 18 weeks, and 89% within the first year.

Neutropenia <1.0 × 10⁹ per L occurred in 1.2% of users in a population-based study of 26,000 clozapine users in Australia and New Zealand (1990–2022) with no fatal cases [6]. The risk was
<table><caption>**Table 1.** European Clozapine Task Force proposals for new clozapine blood monitoring rules in countries under European Medicines Agency regulation</caption><thead><tr><th></th><th>Current SPC<sup>1</sup></th><th>Proposals<sup>2</sup></th></tr></thead><tbody><tr><td>Mandatory routine blood monitoring schedule</td><td>WBC<sup>3</sup> and ANC<sup>4</sup><br>o baseline before initiation<br>o weekly for 18 weeks after initiation<br>o then monthly irrespective of treatment duration</td><td>First 12 months<br>ANC<br>o baseline before initiation<br>o weekly for 18 weeks after initiation<br>o then monthly for 34 weeks<br>After 12 months<sup>5</sup><br>o ANC every 12 weeks if no history of leukopenia or neutropenia during the first year<br>After 24 months<sup>5</sup><br>o yearly ANC if no history of leukopenia or neutropenia during two years</td></tr><tr><td>Standard thresholds for Initiation/continuation</td><td>o ANC ≥ 2.0 x 10<sup>9</sup>/L<br>o WBC ≥ 3.5 x 10<sup>9</sup>/L</td><td>o ANC ≥ 1.5 x 10<sup>9</sup> per L<sup>6</sup></td></tr><tr><td>Monitoring twice a week</td><td>o ANC 1.5–2 x 10<sup>9</sup>/L<br>o WBC 3.0–3.5 x 10<sup>9</sup>/L</td><td>o ANC 1.0–1.5 x 10<sup>9</sup>/L<sup>6</sup></td></tr><tr><td>Discontinuation (red)</td><td>o ANC &lt;1.5x10<sup>9</sup>/L<br>o WBC &lt;3.0x10<sup>9</sup>/L</td><td>o ANC &lt; 1.0 x 10<sup>9</sup> per L<sup>6</sup></td></tr><tr><td>BEN<sup>7</sup> adjusted thresholds for Initiation/continuation</td><td></td><td>o ANC ≥ 1.0 x 10<sup>9</sup> per L<sup>6</sup></td></tr><tr><td>Monitoring twice a week</td><td></td><td>o ANC 0.5–1.0 x 10<sup>9</sup> per L<sup>6</sup></td></tr><tr><td>Discontinuation</td><td></td><td>o ANC &lt; 0.5 x 10<sup>9</sup> per L<sup>6</sup></td></tr><tr><td>Monitoring schedule after clozapine interruption</td><td>interruption &gt; 3 days and &lt; 4 weeks<br>o weekly for 6 weeks then monthly interruption &gt; 4 weeks<br>o weekly for 18 weeks then monthly</td><td>irrespective of the duration of interruption<br>o no need to resume weekly schedule if no history of neutropenia during two cumulative years of monitoring</td></tr></tbody></table>

highest during the first 18 weeks of treatment (weekly incidence 0.13%) and became negligible after 24 months. The incidence of any neutropenic event was very low when clozapine was reintroduced in people with no history of neutropenia over two years of cumulative monitoring. This finding suggests that there is no need to resume a weekly monitoring schedule after a clozapine interruption in people with no history of neutropenia.

Another population-based study of 14,037 clozapine users in Finland (1996–2017) found a cumulative incidence of agranulocytosis of 1.37% with clozapine compared with 0.13% with other antipsychotics [7]. The mortality rate for agranulocytosis was one death in 3,559 people starting clozapine. Compared to modal treatment duration for non-clozapine antipsychotics (12–23 months), the risk of agranulocytosis decreased over time from an adjusted odds ratio of 36 during the first six months of clozapine exposure to 4.38 for exposure ≥54 months: it became then comparable to that observed over the first six months of treatment for other antipsychotics for which no mandatory monitoring is required.

## Stringency of blood monitoring rules already differs between European countries

A review of clozapine monitoring regulations in 102 countries highlighted the wide variability in monitoring rules and in WBC/ANC criteria for stopping clozapine [2]. Although EMA

regulation applies to all EU countries as well as Norway and Iceland, the blood monitoring rules already differ from one country to another [2] (Supplementary Table 1). In several countries, the rule “no blood, no drug” does not apply and monitoring is already relaxed. The recommendations of the Netherlands Clozapine Collaboration Group, set up in 2006, allow for off-label less stringent monitoring rules after the first 18 weeks of treatment if the prescriber and the well-informed patient decide so. Similar recommendations apply to Iceland with the possibility of relaxed monitoring after six months. Monitoring stringency has no impact on the incidence of agranulocytosis but is inversely associated with the rate of clozapine use in each country [2].

Criteria for clozapine discontinuation following a drop in WBC count also vary from country to country. Too stringent criteria may lead to unjustified discontinuation due to transient neutropenia not related to clozapine. Interdisciplinary boards involving psychiatrists and hematologists would be needed to exclude concurrent reasons for ANC decrease.

In most European countries, mild neutropenia, that is, ANC <1.5 x 10⁹ per L requires discontinuation (Supplementary Table 1). However, in a few European countries under EMA regulation, the US Food and Drug Administration (FDA) criteria (ANC <1.0 x 10⁹ per L) are used after 18 weeks [2].

Several countries have adjusted the threshold criteria for clozapine discontinuation for people concerned with benign ethnic neutropenia (BEN) [1] since their access to clozapine is markedly

<footnote n="1">¹Summaries of Product Characteristics;</footnote>

<footnote n="2">²Only Absolute Neutrophil Count criteria are given as the majority of authors (60%) are in favor of restricting mandatory monitoring to ANC based on Food and Drug Administration regulation revisions in 2015; however, no consensus could be reached among the members of the European Clozapine Task Force on this point;</footnote>

<footnote n="3">³White Blood Cells count;</footnote>

<footnote n="4">⁴Absolute Neutrophil Count;</footnote>

<footnote n="5">⁵Even if the frequency of routine mandatory monitoring is reduced, ANC must be performed immediately in the event of possible symptoms of infection (e.g. fever, sore throat, mouth/throat ulcers). Additional ANC may be considered after addition of valproic acid to clozapine, especially during the initiation period.</footnote>

<footnote n="6">⁶Food and Drug Administration criteria;</footnote>

<footnote n="7">⁷Benign Ethnic Neutropenia (hematology consultation may be needed to confirm the diagnosis).</footnote>
restricted under the standard criteria. For instance, the FDA thresh-
old criteria for clozapine discontinuation for BEN is ANC
<0.5 × 10⁹ per L. The BEN-adjusted criteria are not yet applied in
any country under the EMA regulation, leading to discrimination
regarding access to clozapine for the many people living with BEN
in Europe. For example, up to 80% of people of black African or
Caribbean descent have the Duffy-null phenotype of the ACKR1
(A Typical Chemokine Receptor 1) gene associated with BEN.

Reducing barriers to clozapine by revising European blood monitoring rules

Thirty-five years ago, stringent blood monitoring rules were justi-
fied to ensure the successful reintroduction of clozapine. Today,
this stringency no longer matches the reality of the actual
hematological risk, as demonstrated by the growing body of evi-
dence on the temporal pattern of clozapine-induced agranulocyto-
sis. No other drug approved in Europe with a negligible risk of
agranulocytosis after the first year of treatment requires lifelong
monthly blood monitoring.

The European Clozapine Task Force is a group of psychiatrists and pharmacologists practicing in 18 countries under EMA regulation with extensive clinical and research expertise in clozapine. We are deeply concerned about the underuse of clozapine in European countries. We are convinced revising and updating the EMA's blood monitoring rules could help to overcome the major barrier to the use of clozapine [9].

Our proposals for new clozapine blood monitoring rules are detailed in Table 1. Only ANC criteria are given as the majority of authors (60%) are in favor of restricting mandatory monitoring to ANC based on FDA regulation revisions in 2015. However, no consensus could be reached among the members of the European Clozapine Task Force on this point.

Based on the currently available evidence, we propose to:

(i) relax the blood monitoring schedule after 12 months and 24 months of treatment,

(ii) lower ANC threshold for clozapine initiation and dis-continuation,

(iii) use an adjusted threshold for BEN,

(iv) relax monitoring schedule after clozapine interruption,

(v) harmonize (i) to (iv) across Europe.

The benefits of revising the monitoring rules outweigh the potential
risks associated with less stringent rules: allowing more people with
TRS to get clozapine will save lives without increasing the risk of
agranulocytosis.

Conclusion

Access to clozapine is currently severely hampered by multiple
barriers resulting in a real loss of opportunity for many people with
TRS, with a high price being paid by both the users and the
healthcare system. Whenever deemed indicated, clozapine treat-
ment must be initiated as soon as possible to promote recovery and
to increase life expectancy. Better addressing these unmet needs
should be considered as a public health priority by European health
regulatory agencies, as it is currently done by the FDA. More
balanced monitoring rules would contribute to reducing clozapine
underprescription as well as discrimination against people with
BEN. The time has come for revising the rules of clozapine blood
monitoring in Europe.

**Supplementary material.** The supplementary material for this article can be found at http://doi.org/10.1192/j.eurpsy.2024.1816.

**Data availability statement.** Not relevant.

**Financial support.** This research received no specific grant from any funding agency, commercial or not-for-profit sectors.

**Competing interest.** The following authors declare none: Hélène VERDOUX, Robert BITTNER, Alexis LEPETIT, Manuel ARROJO-ROMERO, Christian BACHMANN, Marieke BEEX-OOSTERHUIS, Jan BOGERS, Dan COHEN, Marc DE HERT, Carlos DE LAS CUEVAS, John LALLY, Dolores KEATING, Judit LAZÁRY, Jurjen J. LUYKX, Olalla MARONAS AMIGO, Jimmi NIELSEN, Brian O'DONOGHUE, Pierre OSWALD, Flavian S RADULESCU, Christopher ROHDE, Emilio J. SANZ, Ivona ŠIMUNOVIĆ FILIPČIĆ, Iris E. SOMMER, Selene VEERMAN, Edoardo SPINA, Peter SCHULTE; Alkomiet HASAN is editor of the German (DGPPN) schizophrenia treatment guidelines, first author of the WFSBP schizophrenia treatment guidelines; on advisory boards of and speaker fees from AbbVie, Advanz (speaker fees only), Janssen-Cilag, Lundbeck, Recordati, Rovi, Teva, and Otsuka; Mishal QUBAD has received speaker fees from Recordati; Elias WAGNER was invited to advisory boards from Recordati, Teva and Boehringer Ingelheim; Andreja CELOFIGA participated in lectures for the following companies: Krka, Bonifar, Viatris, Gedeon Richter, Lek, and Lundbeck-Pharma; Domenico DE BERARDIS was speaker/consultant for Angelini, Innova Pharma, Janssen, Lundbeck, Viatris, Rovi and Otsuka Konstantinos; Bjørn EBDRUP is part of the Advisory Board of Boehringer Ingelheim, Lundbeck Pharma A/S; and has received lecture fees from Boehringer Ingelheim, Otsuka Pharma Scandinavia AB, and Lundbeck Pharma A/S; N. FOUNTOULAKIS has received in the past grants, served as a consultant, advisor, or CME speaker, or received support to attend congresses by the following entities: AstraZeneca, Bristol-Myers Squibb, Eli Lilly, Ferrer, Gedeon Richter, Janssen, Lundbeck, Otsuka, Pfizer, the Pfizer Foundation, Sanofi-Aventis, Servier, Shire, and others; Daniel GUINART has been a consultant and/or advisor of has received honoraria from Angelini, Janssen, Lundbeck/Lundbeck Foundation, Otsuka, Teva; he currently receives funding from the European Commission (HORIZON EUROPE) and from the Instituto de Salud Carlos III (ISCIII); Miloslav KOPEČEK is member of advisory board and speakers' honoraria from Angeliny Pharma and Lundbeck; Espen MOLDEN has received speaker's honorarium from Lundbeck and Otsuka; Marina SAGUD has presented lectures for the following companies: Angelini, Belupo, Gedeon Richter, Johnson & Johnson, Krka Farma d.o.o., Lundbeck, Pliva d.o.o., and Viatris; participated in clinical trials as an principal investigator for Boeringer Ingelheim; and is a member of the advisory board of Lundbeck and Pliva; Heidi TAIPALE has participated in research projects funded by grants from Janssen to her employing institution; and has received lecture fees from Gedeon Richter, Janssen, Lundbeck and Otsuka; Jari TIIHONEN has participated in research projects funded by grants from Janssen to his employing institution; has served as a consultant for Healthcare Global Village, HLS Therapeutics, Janssen, Lundbeck, Orion, Teva, and WebMD Global; and has received honoraria from Janssen, Lundbeck, and Otsuka; Heli TUPPURAINEN has received speakers fee from Lundbeck; Alina WILKOWSKA has received research support from Angelini, Biogen, Eli Lilly and Company, Janssen- Cilag, Lundbeck, Polpharma, Sanofi, Termedia, and Valeant.

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