Objectives: As yet, there is no European data standard for naming and describing oncology regimens. To enable real-world cancer treatment data comparisons, the Oncology Data Network created a unified reference database for systemic anti-cancer regimens used in practice across Europe. Data are extracted from clinical systems and mapped to a single standard called the "Core Regimen Reference Library (CRRL)". An automated matching algorithm has been designed based on: drug combinations; administration schedule; and dosing and route of administration. Incomplete matches are flagged for expert review. The aim of this pilot study is to have an expert pharmacist panel test the algorithm's feasibility by comparing computerised and manual matching of regimens that are currently in use in different European countries. Methods: The combined team pooled a diverse sample of 47 reference regimens used in Europe for solid and haematological cancers. These were then codified to the developed common data standard and the algorithm was used to match them to the CRRL. The expert pharmacist panel from the European Society of Oncology Pharmacy (ESOP) selected 12 regimens from the sample set, ranging from simple to complex, and performed a single-blind test of the algorithm, by systematically matching each original regimen to the CRRL. Results: ESOP validated the algorithm's feasibility based on full concurrence between manual and computer matches thereby validating the algorithm rules and logic with regard to what defines the core characteristics of a regimen and how to compare similarities and differences. Conclusions: ESOP's validation of the matching algorithm and approach to curating a master library provides confidence in their utility for reliable comparison of real-world regimen usage across Europe.