Welcome to the Marbach Castle Drug-Drug Interaction Workshop Series

The DDI workshop series is a non-profit programme to exchange research-based knowledge on drug-drug interactions (DDIs) among all interested stakeholders from pharmaceutical industry, regulatory authorities, academic and health care delivery backgrounds and perspectives.

The overall objective of the international Marbach Castle DDI Workshop series is to improve and disseminate the scientific knowledge about drug-drug interactions (incl. food-drug and herb-drug interactions), and to foster communication for efficient preclinical and clinical investigation of DDIs across disciplines and organisational boarders.

The goal is safer use of pharmaceutical products especially in geriatric and medically complex patient populations with various co-morbidities and increasing poly-pharmacotherapy.


DDI Workshop 2023 – Registration is now open!

The upcoming Workshop will take place from June 4th to June 6th, 2023.


DDI Workshop Programme 2023

In its 13th year, and as we return to face-to-face modality for ­second time after one-year COVID down­time, the Workshop will cover a number of highly important and current DDI topics in depth.

The 2023 Workshop will open with a plenary lecture on pharmacodynamic (PD) drug interactions and whether these could be predicted from the first principles under the framework of ‘Model-Informed Drug Development’ (MIDD). This will be followed by a talk presenting selected examples of PD interactions of clinical importance.

The second session will be entirely dedicated to the recently issued first draft version of the International Council for Harmonization (ICH) drug interaction guideline M12.  Attendees will hear separate talks on the in vitro and in vivo aspects of the guideline.  In addition, a represen­tative on behalf of IQ, will present the industry perspective on the current version of ICH M12 and links with ongoing debates over ICH M13 on modelling.  Finally, a panel discussion with representatives from various regulatory bodies will complete the session, and is expected to bring valuable insights into regulatory thoughts towards global harmonization.  

The third session on Day 1 of the meeting will feature for the first time the emerging topic of biomarkers for detection of clinical DDIs. Specifically addressed will be biomarkers reflecting DDIs affecting OATP transporters, and the role of liquid biopsy in assessing the induction / suppression of enzymes and drug transporters. Finally, a general overview will be presented to review where we currently are in the field of DDI biomarkers, and to shed light on what has been settled yet, and what has not. This talk will also address the specificity and feasibility of developing tools to identify biomarkers for the detection of DDIs.

On Day 2 of the Workshop for the first time a session will be dedicated to the rarely acknowledged field of smoking interaction studies. The key talk of this session will comprehen­sively review methodological aspects of smoking interaction studies that have been applied over the last three decades, and will discuss implications for future smoking interaction trials. 

A following panel discussion will reflect and compare methodological standards of food effect studies vs. smoking interaction studies, thereby highlighting important differences.  

The second session on Day 2 of the meeting will address DDIs that are caused by pharmaceutical excipients. The first talk will present information on FDA scientific efforts on the investigation of excipient DDIs, while the following talk will share existing industry ­experience. The last talk of this session will provide an overview on the DDI potential of major pharma­ceutical excipients on transporters and enzymes.

Another regulatory session will conclude Day 2 of the Workshop. The first talk of this session will provide an overview of 2022 NDA reviews with the aim to foster understanding of the risks of metabolism- and transporter-based DDIs with novel drugs approved by the US FDA. The final talk of the meeting will ­provide an update on the current PBPK ­model repository.

As always, there will be an opportunity for Workshop participants to submit abstracts for poster presen­tations throughout the Workshop. 

All sessions will provide plenty of oppor­tunity for scientific and regulatory exchange and networking. 

As always, the topics of the 13th inter­national DDI Workshop will be covered by distinguished inter­national scientists, representatives from various national regulatory agencies, and experts from academia, pharmaceutical companies, contract research organizations as well. 

The Workshop Organizers


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Supporting organisations