Comparison of pharmacogenomic guidance in Australian prescribing resources and international pharmacogenomic guidelines

BACKGROUND: Pharmacogenomic-guided medication management optimises drug therapy to enhance patient outcomes. Despite clinical utility, implementation in Australia remains limited, partly due to the lack of clear and consistent guidance. AIM: This study evaluated the presence and consistency of pharmacogenomic testing indication categories and therapeutic recommendations between Australian prescribing resources and international pharmacogenomic guidelines. METHODS: Testing indications were compared between Dutch Pharmacogenetics Working Group (DPWG), Royal College of Pathologists of Australasia (RCPA) and Australian prescribing resources (Australian Medicines Handbook (AMH), Therapeutic Guidelines (TG), Therapeutics Goods Administration (TGA) and eviQ). Therapeutic recommendations were compared between Clinical Pharmacogenetics Implementation Consortium (CPIC), DPWG, and Australian prescribing resources. Weighted kappa was used for analysis (n > 10) and interpreted using the Landis and Koch scale. RESULTS: Among Australian resources, AMH included the highest proportion of testing indications (28%, 19/67); however, it remains an overall low proportion. Testing indications were most consistent between RCPA and TG, with 50% (5/10, 95% CI 0.19-0.81) concordant (e.g. mercaptopurine/TPMT testing 'recommended' in both). For therapeutic recommendations, AMH demonstrated substantial agreement with DPWG (κ 0.80, 95% CI 0.61-0.98); however, 11% (3/27) of recommendations were discordant (e.g. capecitabine/DPYD deficiency 'dose adjustment' in DPWG and 'contraindication' in AMH). Within Australian resources, most (88%, 7/8, 95% CI 0.47-1.00) testing indications were concordant, while for therapeutic recommendations, just over half (57%, 4/7, 95% CI 0.18-0.90) were concordant. CONCLUSIONS: Australian prescribing resources contain limited and inconsistent pharmacogenomic information. Greater harmonisation is needed to support decision-making and facilitate broader pharmacogenomic implementation.