(AG) Utilization of Drugs with Pharmacogenetic Dosing Recommendations in Switzerland: A Descriptive Study Using Swiss Claims Data

Saturday, August 27, 2022

8:00 AM – 6:00 PM CEST

Location: Hall E South

Publication Number: 667

Presenting Author(s)

Nina L. Wittwer, n/a
– PhD Student, Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland, University of Basel, Basel, Basel-Stadt, Switzerland

Co-Author(s)

Christoph Meier, Prof Dr
– Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland, Switzerland
Carola A Huber
– Department of Health Sciences, Helsana Insurance Group, Zürich, Switzerland, Switzerland
Henriette E Meyer zu Schwabedissen
– Biopharmacy, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland, Switzerland
Samuel Allemann
– Pharmaceutical Care, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland, Switzerland
Cornelia Schneider
– Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland, Switzerland

Background: In Switzerland pharmacogenetic testing is not routinely implemented into primary care, although 167 substances (PGx drugs) on the Swiss market contain information about pharmacogenetics in their drug label, of which 93 are deemed to be actionable.

Objectives: The aim of this study was to assess the exposure of the Swiss population to PGx drugs and to identify the most commonly used PGx drugs and thereby the most relevant PGx genes.

Methods: We assessed the utilization of 90 drugs associated with dosing recommendations linked to variants in 24 genes in the Pharmacogenomics Knowledge Base (PharmGKB) using Helsana claims data between 2016 and 2020. Helsana is a large Swiss health insurance company covering approximately 1.2 million persons with basic health insurance per year. We calculated absolute and relative numbers of PGx drug exposure, and ranked the substances and associated genes based on the number of exposed patients.

Results: From 2016 to 2020, in total 885 866 persons were registered at Helsana during the whole study period. Mean age was 43.4±10.9 years, 52.4% were women and 55.9% of the persons had at least 1 drug claim. 51.1% of the population were exposed to at least 1 PGx drug during the 5-year window, 11.4% had ≥5 PGx drugs. The top 3 PGx drugs were ibuprofen (31.2%), pantoprazole (27.7%) and tramadol (12.3%). The total number of users varied from 1 for imipramine to 276 392 for ibuprofen. At least 9 out of 10 PGx drug users were exposed to drugs targeting the musculoskeletal system (38.7%), the alimentary tract and metabolism (37.8%), or the nervous system (31.8%). CYP2C19 (65.7%), CYP2C9 (64.6%), and CYP2D6 (48.5%) were the genes with the highest numbers of persons exposed to at least one associated PGx drug during the whole five-year period. Seven genes (CYP2C19, CYP2C9, CYP2D6, SLCO1B1, HLA-B, MT-RNR1, and VKORC1) were responsible for over 94% of all potential drug-gene interactions..

Conclusions: The exposure to PGx drugs is high in the Swiss population, suggesting that a substantial amount of the Swiss population could benefit from preemptive pharmacogenetic testing.