Patients with cancer are at risk to endure a drug-drug interaction (DDI) with their oncolytic drugs. To facilitate the safe prescription and use of oncolytics, the freely available website www.cancer-druginteractions.org was introduced. Hereby we present the results of the use of this online DDI resource since the launch in June 1st, 2017.
For the most frequently used co-medications (>400) in cancer patients DDI potential was reviewed based on registration documents and scientific literature. A simple “traffic light” system was used to warn for the interaction potential. Background information and level of evidence is provided in the summary for each interaction. Since the launch of the website the demographic use, the number of unique visitors and the number and severity of the interactions consulted are monitored every 3 months.
34 targeted oncolytics used for ten different malignancies have been added to the website. These represent 24 targeted oral oncolytics and 10 monoclonal antibodies (MoABs). Between June 1st, 2017 and March 31st, 2018 a total of 11,295 searches has been performed by 3,428 unique visitors from 35 countries. 78% of the searches were performed for oral oncolytics and 22% for MoABs. 20.8% of the searches showed a potential interaction which requires action of the prescriber. The table gives an overview of the searches performed. Frequently checked co-medications were for example coumarins, PPIs, dexamethasone, metamizole and aspirin. Currently, a user-friendly app is under development which will be launched in October 2018.Table: 1801P
Overview of DDI queries
|Interaction classification ‘traffic light’ (%)|
|Green No clinically significant interaction||63.3|
|Yellow Interaction of weak/moderate intensity; no a priori dosage adjustment required||15.9|
|Amber Potential interaction which may require dosage adjustment or close monitoring||14.3|
|Red Do not co-administer||6.5|
|Countries consulted the website (%)|
|Other European countries (top 3: Spain, France, Switzerland)||7|
|USA and Canada||3|
|Asia-Pacific (top 3: Australia, India, Hong Kong)||2|
Thus far, the DDI checker is being used all over the world. More than 20% of the performed searches showed a clinically relevant interaction. The freely available website, and the soon to be launched app, will facilitate health care professionals’ awareness of potential DDIs between oncolytics and frequently used co-medications and this supports safe prescription.
Clinical trial identification
Legal entity responsible for the study
Radboudumc and University of Liverpool.
Abbvie, Astellas, AstraZeneca, Boehringer Ingelheim, Bristol-Myers Squibb, Gilead, Ipsen, Janssen, Pfizer, Roche, Sanofi.
S.H. Khoo: Advisory board: Merck, ViiV; Corporate sponsored research: ViiV, Gilead, Merck, Janssen; Other: Abbvie, Astellas, AstraZeneca, Boehringer Ingelheim, Bristol-Meyers Squibb, Gilead, Ipsen, Janssen, Pfizer, Roche, Sanofi. N. van Erp: Research funding: Novartis, Astellas, Janssen Cilag, AstraZeneca, GSK, Boehringer Ingelheim, Gilead, Roche, Pfizer, Sanofi. F.G. Jansman: Advisory board: Amgen, Servies. All other authors have declared no conflicts of interest.