Personalized Pharmacotherapy

Missed-Dose Management in Theory and Practice: Analysis of Official Instructions and Real-World Behavior

Nonadherence can have clinically significant consequences, even after a single missed dose, particularly for drugs with low tolerance for missed doses. Although missed doses are common—most often due to forgetfulness—guidance on how to manage them is inconsistent and has not been sufficiently studied. While research focuses on improving adherence, real-world patient behavior and the clarity of missed-dose instructions remain under-explored.

This PhD project investigates missed-dose management from the perspectives of the literature, regulatory bodies, and real-world patients through four planned phases.

1. A comprehensive review will identify and analyze existing recommendations on how to manage missed doses across therapeutic areas.
2. Using quantitative Natural Language Processing (NLP), all Swiss drug labels will be systematically analyzed to determine whether and how they provide instructions for situations involving missed doses. We will examine which therapeutic classes include guidance, the thematic content of these instructions, and whether the wording provides clear, actionable advice for real-life situations.
3. To understand real-world behavior, semi-structured interviews will be conducted with patients who regularly take medications and have experienced difficulties with adherence, as well as with healthcare professionals involved in medication dispensing and counseling. This phase will explore how missed doses are handled in daily life, perceived uncertainties, and counseling practices.
4. Building on the qualitative findings, the project will proceed to a quantitative phase to assess and validate emerging subjects in a larger population.

Optimizing Medication Adherence Using Mobile Health Solutions

In an era of increasing digitalization, medication adherence apps represent a promising approach to supporting medication use in a way that can be easily integrated into patients’ daily lives. Currently, the market offers a wide variety of adherence apps that vary in functionality and quality.

This research project consists of three phases: understanding the needs of patients and healthcare professionals regarding adherence apps, testing the feasibility of an app-based service in practice, and developing strategies for future implementation. In the first phase, we investigated the expectations and needs of patients and healthcare professionals regarding adherence apps, including key features, design considerations, and overall functionality. In two studies (SMAPP Study: NCT06126900; PIPPI Study: NCT06094062), an adherence app was evaluated in real-world practice and offered to patients through participating pharmacies. This approach enabled us to gain comprehensive insights into how app-based adherence solutions can be integrated into routine pharmacy workflows. The real-world testing highlighted potential barriers and challenges faced by both patients and healthcare professionals. Based on these findings, we have developed implementation strategies and gathered the perspectives of Swiss pharmacy staff regarding their usefulness and feasibility. These strategies now require evaluation in clinical practice to further determine how adherence apps can be effectively implemented within routine care.

Publications:

• Messner K, Sutter V, Allemann S, Arnet I. Exploring the Fit Between the Outputs of Freely Available Medication Adherence Apps and Users’ Needs: Mixed Methods Study. JMIR mHealth and uHealth Dec 16, 2025;13(1):e68919. doi: 10.2196/68919

The Hidden Complexity of Changing Treatment Providers in Epilepsy Care

Epilepsy is a common neurological disorder that affects the cognitive and psychological functioning of those affected. Beyond the challenges posed by the disease itself, treatment experiences play a crucial role in patients’ quality of life. In particular, switching between different manufacturers of the same active ingredient may increase the risk of adverse events such as breakthrough seizures, which is why such switches are often discouraged in clinical practice.

The aim of this project is to examine whether the adverse events reported during manufacturer switches are due to pharmacological differences or to nonpharmacological mechanisms, such as nocebo effects. To address this issue comprehensively, the project investigates how national and international guidelines address manufacturer switches, what evidence they rely on, and whether nonpharmacological influences are taken into account. It also explores how hospitals and blister centers internationally manage their antiseizure medication portfolios to maintain continuity of care. Furthermore, the challenges and experiences faced by community pharmacies in daily practice are examined. In this context, patient adherence and trust in their therapy play a central role, as stable therapeutic regimens rely on patients feeling confident and well supported in their treatment.

An initial mixed-methods study examined the difficulties community pharmacists face when substituting generic controlled substances and identified the types of support they consider necessary. The findings revealed that medications acting on the nervous system, particularly antiseizure medications, pose specific challenges during manufacturer switches. These results form the basis for the current investigation into manufacturer switches involving the same active ingredient in antiepileptic medications. By examining both pharmaceutical and nonpharmaceutical aspects, the project aims to deepen our understanding of this issue and contribute to safer and more consistent care for individuals with epilepsy.

Publications:

• Keller IM, Alexa JM, Meier MW, Allemann SS. A mixed-methods study investigating the potential and challenges of generic substitution of controlled substances in community pharmacies. Explor Res Clin Soc Pharm., 2025:100622. https://doi.org/10.1016/j.rcsop.2025.100622

Pharmacogenetic Testing of Patients with Adverse Drug Reactions or Treatment Failure

A patient’s genetic makeup influences a drug’s efficacy and safety profile. This study (ClinicalTrials.gov identifier: NCT04154553; EKNZ ID: 2019-01452) aims to summarize individual cases in which pharmacogenetics has been applied during pharmaceutical care. Health-related data from patients experiencing treatment failure or adverse drug reactions is collected and will then be supplemented with pharmacogenetic testing during pharmaceutical care at a study pharmacy. The patient data (diagnoses, medications, and results of pharmacogenetic testing) is standardized to generate a compilation of case reports. The primary objective is to compile case reports in which pharmacogenetic testing is used to determine the hereditary component of a patient’s susceptibility to treatment failure and/or adverse drug reactions. The experience gained from the compiled cases will serve as the basis for developing a reliable standard operating procedure for pharmacogenetic testing in community pharmacies. The cases will be supplemented with information on additional parameters reported in the literature to affect the efficacy or safety of the respective drug.

Publications:

• Bollinger A, Stäuble CK, Jeiziner C, Wiss FM, Hersberger KE, Lampert ML, Meyer zu Schwabedissen HE, Allemann SS. Genotyping of Patients with Adverse Drug Reactions or Therapy Failure: Database Analysis of a Pharmacogenetics Case Series Study. Pharmgenomics Pers Med. 2023;16:693-706
  doi.org/10.2147/PGPM.S415259

PrePGx Study: Pharmacist-Guided Preemptive Pharmacogenetic Testing in Antidepressant Therapy

The PrePGx study (ClinicalTrials.gov identifier: NCT04507555; EKNZ ID: 2020-01535) investigates whether pharmacogenetic testing can improve the effectiveness and tolerability of antidepressant therapy in patients with major depressive disorder. Since only about half of patients respond to the first antidepressant treatment they receive, the study aims to evaluate whether a more personalized treatment approach based on genetic information can improve treatment outcomes.

The study assesses whether preemptive pharmacogenetic testing, interpreted and applied by clinical pharmacists, can help physicians select and dose antidepressant medications more effectively.

The study is conducted as an open-label, randomized controlled trial across four psychiatric clinics in Switzerland. Adult inpatients diagnosed with a moderate-to-severe depressive episode are recruited upon hospital admission. If a change or adjustment to antidepressant medication is required after the first week of hospitalization, participants are randomly assigned to one of two groups. In the intervention group, treatment decisions are supported by pharmacist-guided pharmacogenetic testing, while in the control group, antidepressant therapy is selected according to standard clinical practice without access to genetic testing results. Patients who do not require a medication change are followed in an observational group.

The primary objective is to compare treatment response after four weeks of antidepressant therapy between the intervention and control groups. The findings are expected to provide valuable insights into how pharmacogenetic information and interprofessional collaboration between physicians and pharmacists can support more personalized antidepressant treatment in psychiatric care.

Publications:

• Stäuble, C.K., Lampert, M.L., Allemann, S., et al. Pharmacist-guided preemptive pharmacogenetic testing in antidepressant therapy (PrePGx): study protocol for an open-label, randomized controlled trial. Trials 22, 919 (2021). https://doi.org/10.1186/s13063-021-05724-5

• Wiss, Florine M., MSc¹⁻²; Krieg, Christian D., MSc¹; Lampert, Markus L., PhD¹⁻²; Meyer zu Schwabedissen, Henriette E., MD³; Stäuble, Céline K., PhD¹⁻³; Mikoteit, Thorsten, MD4,5; Imboden, Christian, MD4,6; Allemann, Samuel S., PhD1. CYP2D6 Phenotype as a Predictor of Adverse Drug Reactions in Patients Treated With Trazodone: An Exploratory Pharmacogenetic Study. Journal of Clinical Psychopharmacology 46(2):pp. 179–188, March/April 2026. | DOI: 10.1097/JCP.0000000000002123

Investigating the Role of Pharmacogenetic Information on Medication Adherence in Precision Medicine

Pharmacogenetic (PGx) testing is increasingly used to personalize drug therapy and enhance medication safety and effectiveness. However, its impact on patient behavior, particularly medication adherence, remains poorly understood. To address this gap, this research program comprises two interconnected projects: the theory-based development of a questionnaire and its integration into a prospective longitudinal cohort study.

The first project involved the systematic development of a questionnaire to assess determinants of medication adherence following the receipt of PGx information. A secondary analysis of a scoping review (13 publications) examined behavioral responses to PGx-informed treatment recommendations. Findings were mapped onto the Theoretical Domains Framework (TDF), informed by the COM-B model. Results show that adherence following PGx testing is influenced by behavioral factors beyond genetic optimization alone. In particular, health literacy, the quality of the physician–patient relationship, and communication practices influence patients’ understanding, trust, and motivation to follow PGx-guided recommendations, highlighting the importance of cognitive, social, and emotional mechanisms.

In the second project, the questionnaire will be validated and implemented within an ongoing prospective cohort study (EKNZ 2023-00157) conducted by the Pharmaceutical Care Research Group (PCRG) at the University of Basel. Patients in the cohort study previously underwent PGx testing and received individualized recommendations. Annual follow-ups over three years collect medication- and health-related data to assess how often PGx information informs treatment decisions, what adjustments are made, and why recommendations are followed or not followed. With the integration of the newly developed questionnaire, we will additionally measure the extent and reasons for nonadherence, enabling a systematic assessment of factors that may positively or negatively influence medication adherence.

Based on the premise that genetic information remains stable over time, the central hypothesis is that PGx results obtained once should inform future prescribing decisions. By combining theory-driven instrument development with longitudinal real-world evaluation, this research advances understanding of the behavioral mechanisms underlying medication adherence in PGx-informed care and supports the optimization and sustainable integration of PGx into clinical practice.

Publications:

• Bollinger, Anna, et al. "Impact and enablers of pharmacogenetically informed treatment decisions—a longitudinal mixed-methods study exploring the patient perspective." Pharmacy 13.1 (2025): 14.