Abstract
The European Medicines Agency’s conditional marketing authorization (CMA) aims to expedite patient access to medicines for unmet medical needs by shifting a part of the drug development process post-authorization. We highlight ethical issues surrounding CMA, comprising (i) the complexity of defining unmet medical need; (ii) poor understanding of CMA and its impact on informed consent; (iii) hope versus unrealistic optimism; (iv) implications of prolonged post-authorization studies and potential patient harm; (v) rights and duties of patients surrounding participation in post-authorization studies; (vi) access to previously authorized CMA medicines; and (vii) the “benefit slippage” phenomenon, defined as the gradual shift of strict criteria to less strict criteria. We propose a comprehensive research agenda to address these ethical issues, and stress the need for multi-stakeholder engagement to ensure patient-centered use of CMA.
1 Introduction
To enable early access to promising medicines for patients with unmet medical needs–such as rare diseases or poorly treatable cancers–regulatory authorities have implemented expedited pathways that allow marketing authorization of medicines based on preliminary (“non-comprehensive”) data. Expedited pathways are in place in for example the European Union (EU), the United States (US), Japan, Canada, and other countries (). In the EU, the European Medicines Agency’s (EMA) conditional marketing authorization (CMA) has been in place since 2006 (Box 1). Until the end of 2023, 89 CMAs were granted, of which almost half were granted in the last four years (N = 42, 47%; Figure 1).
BOX 1 Characteristics of the conditional marketing authorization in the European Union (2bibrB2).
In the European Union, medicines can be granted conditional marketing authorization (CMA) based on non-comprehensive data when they are (i) intended for treatment, prevention or diagnosis of a seriously debilitating or life-threatening disease, (ii) designated an orphan medicine by the European Commission, or (iii) to be used in emergency situations, such as the coronavirus disease 2019 (COVID-19) pandemic. In addition, the following requirements should be met:
- i.
The benefit-risk balance of the medicine is considered positive based on the available evidence;
- ii.
It is likely that the developer can provide comprehensive data in a timely manner to resolve important uncertainties;
- iii.
An unmet medical need is expected to be fulfilled by the medicine; and
- iv.
The benefits to public health of the immediate availability of the medicine outweigh the risks inherent in the fact that additional data are still required.
To facilitate that comprehensive data become available and important remaining uncertainties about safety and efficacy are resolved, post-authorization studies called “specific obligations” are imposed as legally binding conditions of the CMA. Each year, the developer must submit a report describing the status of the specific obligations, after which the CMA can be renewed for another year. A continued positive benefit-risk balance is critical for maintaining the CMA. Upon completion of the specific obligations, the CMA can be converted to a standard marketing authorization.
The CMA is distinct from the authorization under exceptional circumstances for which comprehensive data are not expected to become available at all.
FIGURE 1
CMA aims to provide patients with early access to promising medicines through regulatory flexibility. It can offer a valuable opportunity for patients who often have no other options to meet their medical need. On the other hand, CMA comes with heightened uncertainty about benefits and risks and impacts several aspects of the drug development process. Moreover, in Europe, actual patient access is often dependent on national pricing and reimbursement processes following authorization. In this paper, we present an overview of ethical issues relevant to CMA and propose a research agenda to help further the responsible introduction of new medicines granted CMA in clinical practice and the use of CMA as a regulatory tool.
2 From CMA requirements to ethical issues
The CMA pathway forms a unique context in which urgent patient needs must be balanced with ensuring the safety and efficacy of medicines. This context builds on three ethically relevant characteristics of CMA (Box 1). The first characteristic is unmet medical need. The CMA’s primary aim is to provide patients with unmet medical needs with early access to promising medicines. Therefore, the main ethical driver for the CMA is the ethical principle of beneficence, which entails the duty to promote the health and wellbeing of patients with unmet medical needs. The second characteristic is uncertainty about the benefit-risk balance. The CMA introduces risks inherent to the reliance on initial, non-comprehensive data about the safety and efficacy of a new medicine. The third characteristic comprises mandatory post-authorization studies to obtain comprehensive data and resolve important remaining uncertainties (hereafter CMA studies). During these studies, patients in clinical practice face increased uncertainty about benefits and risks compared to patients treated with medicines granted standard marketing authorization. The initial assessment of the benefit-risk balance is not always confirmed with the emerging data from CMA studies (
The combination of non-comprehensive evidence at initial marketing authorization and the subsequent mandatory CMA studies moves a part of the drug development process, traditionally performed in the highly controlled research setting, into regular clinical practice. Medicines that not (yet) meet the scientific standard of comprehensive evidence are nonetheless released in the clinical setting in which different actors make decisions and the ethico-legal regulations for treatment apply alongside those for post-authorization research. This results in a hybrid situation in which the medicine is still in the research stage as well as part of (standard) clinical care. Current ethical norms and regulations guiding the drug development process are not optimally suited for such hybrids.
3 Ethical issues related to CMA
Ethical issues related to CMA (Figure 2) are described below and derived from an in-depth analysis of the context of CMA and its implications for the ethical delivery of healthcare. The issues described in this paper are highlighted for their direct impact on CMA stakeholders and their potential to inform and refine ethical guidelines and policy development. Therefore, for each ethical issue, needs for future inquiry are discussed, establishing a comprehensive research agenda for CMA. Although the analysis focuses on ethical issues in the context of CMA, some may also apply to other contexts.
FIGURE 2

Relationships between characteristics of conditional marketing authorization (CMA) and ethical issues. CMA requirements result in three ethically relevant characteristics of CMA: addressing an unmet medical need, uncertainty about the benefit-risk balance, and mandatory CMA studies. These characteristics and their intersections provoke ethical issues, which are listed in bold. Below each ethical issue, the implicated ethical principles and values are shown. CMA, conditional marketing authorization.
3.1 Defining unmet medical need
Defining “unmet medical need” for CMA presents an ethical challenge as this definition impacts priority setting in diseases and patient groups for expedited regulatory pathways. The current EU regulatory framework identifies unmet medical need as “a condition for which there exists no satisfactory method of diagnosis, prevention or treatment authorized in the Union or, even if such a method exists, in relation to which the medicinal product concerned will be of major therapeutic advantage to those affected” (
Various stakeholders have suggested changes to the definition of unmet medical need (
Given the significant influence of the definition of unmet medical need on healthcare priorities and resource allocation, researching how to refine this definition is important. Such research should aim to include perspectives of different stakeholders. One way to achieve this could be through multi-criteria decision analyses (
3.2 Informed consent and poor understanding of CMA
Voluntary informed consent is a fundamental ethical requirement for clinical care as well as medical research. To fulfill this requirement, patients, physicians, and researchers need to understand the uncertainties surrounding the benefit-risk balance of medicines granted CMA. Studies show that patients and healthcare professionals often misunderstand the disparities in data that may underlie new medicines. For example, Schumacher et al. (
Physicians also need to have sufficient understanding to communicate effectively with their patients (
This jeopardizes the physician’s duty to adequately explain information and subsequently impacts voluntariness and the quality of the patient’s informed consent (
3.3 Hope and unrealistic optimism
A combination of dire need and the glimpse of a solution may foster unrealistic expectations of medicines granted CMA among patients and families. Scholars have debated the role of hope, optimism, and realism in access to investigational drugs (
False or unrealistic optimism is a cognitive bias where individuals believe they are less likely to experience adverse outcomes and more likely to experience positive outcomes. Unrealistic optimism is distinct from being misinformed (as discussed in relation to informed consent) since it operates as an internal bias undermining the accurate appreciation of risks and benefits of a treatment. This can adversely affect patients’ health and wellbeing (
On the other hand, some scholars suggest that unrealistic optimism is not as harmful as is often thought. They argue that unless such optimism leads to choices that are clearly misaligned with patients’ values and goals, it may not be detrimental to autonomy (
The distinction between beneficial and detrimental expectations is crucial, and conflating them overlooks the possible harms of false hope or optimism (
3.4 Duration of CMA studies and exposure to harm
The CMA of ataluren is currently under discussion after 10 years of CMA status and the indication of vandetanib was restricted after 11 years (
In contrast, the CMAs for olaratumab and belantamab mafodotin were revoked and not renewed after less than three and four years on the market, respectively (
Further research should identify the ethical and social factors that define the optimal duration of CMA studies. This exploration should aim to inform a discussion on acceptable timeframes for the completion of CMA studies and the subsequent decision-making process regarding the conversion or withdrawal, revocation or non-renewal of CMAs, thereby prioritizing the perspectives of patients, physicians, and society.
3.5 Duty to participate in research
The need for efficient CMA studies to resolve uncertainties about safety and efficacy raises another ethical question: Should access to a medicine that is granted CMA come with a duty to participate in CMA studies? Advocates for such a duty argue that individuals who enjoy the benefits of the healthcare system have a moral responsibility to contribute to the medical knowledge that supports it (
However, this stance encounters several ethical challenges. First, it may interfere with the principle of voluntariness of research participation—a cornerstone of research ethics underscored in international guidelines (
Investigating how to shape a duty to participate in a way that avoids these ethical pitfalls could be the focus of further research. For instance, conceptualizing this duty as an act of solidarity in advancing medical practice rather than a forced obligation could shift perspectives. Solidarity, as suggested by Hollestelle et al. (
3.6 Access to previously authorized CMA medicines
The experience with restricting indications and withdrawing, revoking or not renewing CMAs due to unmet specific obligations is limited. Meanwhile, losing access to a medicine poses an under-discussed ethical issue in the conceivable scenario when individual patients demonstrate benefit despite a lack of evidence of a favorable benefit-risk balance at the population level.
This scenario shares similarities with post-trial access, as delineated in the Declaration of Helsinki’s Article 34 (
3.7 Benefit slippage
The aim of CMA to help patients with unmet medical needs may result in so-called “benefit slippage.” Juth (
Concerns about benefit slippage have also been expressed by, for example, Swedish governmental organizations. They fear that the European Commission’s proposals for increased use of expedited regulatory pathways will lower evidence standards (
4 Discussion
Our study of the ethical issues related to CMA reveals the merging of research and clinical practices as a root cause of ethical tension. Historically, these two domains have been distinct (
To further improve the regulatory and clinical practices of CMA, it is crucial to actively involve patients, clinicians, and ethicists. Their collaboration is essential in areas like defining unmet medical need, ensuring informed consent, and managing patient expectations. Empirical research can provide insights relevant to specific ethical complexities in the context of CMA. Optimal use of existing best practices (i.e., for informed consent) can also help diminish ethical tension. Addressing the complexities in optimizing CMA study durations, potential restriction, withdrawal, revocation or non-renewal of CMA, and the phenomenon of benefit slippage requires a collaborative ecosystem that comprises all stakeholders, including pharmaceutical companies and policymakers.
In conclusion, the research agenda proposed in this paper provides the starting point for fostering an ethically grounded and patient-centered approach to using CMA, prioritizing welfare and minimizing the risk of harm in the introduction and use of promising new medicines.
Statements
Author contributions
MM: Conceptualization, Formal analysis, Investigation, Visualization, Writing – original draft, Writing – review & editing. GT: Conceptualization, Formal analysis, Funding acquisition, Investigation, Project administration, Supervision, Visualization, Writing – original draft, Writing – review & editing. YT: Formal analysis, Investigation, Writing – original draft, Writing – review & editing. RL: Formal analysis, Writing – review & editing. JD: Supervision, Writing – review & editing. LB: Conceptualization, Formal analysis, Investigation, Project administration, Supervision, Visualization, Writing – original draft, Writing – review & editing.
Funding
The authors declare that financial support was received for the research, authorship, and/or publication of this article. The work for this article was in part funded by ZonMw (The Netherlands Organisation for Health Research and Development), through the TAILORED project: Toward a human iPSC neuronal platform for neurodevelopmental disorder therapeutic discovery, project number 10250022110002 (2021-2026). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Publisher’s note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
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Summary
Keywords
conditional marketing authorization, research ethics, clinical ethics, expedited regulatory pathways, unmet medical need, uncertainty, informed consent, European Medicines Agency
Citation
Maksimova MV, van Thiel GJMW, Tromp Y, Lechner R, van Delden JJM and Bloem LT (2024) Balancing ethical norms and duties for the introduction of new medicines through conditional marketing authorization: a research agenda. Front. Med. 11:1408553. doi: 10.3389/fmed.2024.1408553
Received
28 March 2024
Accepted
13 June 2024
Published
24 June 2024
Volume
11 - 2024
Edited by
Carla Matos Torre, University of Lisbon, Portugal
Reviewed by
Cristina Sampaio, CHDI Foundation, United States
Viviana Giannuzzi, Fondazione per la Ricerca Farmacologica Gianni Benzi Onlus, Italy
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Copyright
© 2024 Maksimova, van Thiel, Tromp, Lechner, van Delden and Bloem.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Lourens T. Bloem, l.t.bloem@uu.nl
Disclaimer
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.