DPYD Testing: Safer Fluoropyrimidine Use & Cost Savings
- New data presented at the 2025 American Society of Clinical Oncology (ASCO) meeting highlights the importance of DPYD genotyping in optimizing fluoropyrimidine (FP) chemotherapy.
- Fluoropyrimidines, like 5-FU and capecitabine, are standard treatments for gastrointestinal and other solid tumors.
- Grace Nguyen, a clinical pharmacogenomics specialist at Atrium Health Levine Cancer Institute, presented a study evaluating 49 patients with DPYD variants.
New ASCO 2025 data reveals that DPYD genotyping considerably boosts the safety of fluoropyrimidine chemotherapy and cuts costs, a crucial advancement in oncology. This study underscores the vital role of pre-treatment DPYD testing in minimizing severe toxicity risks associated with fluoropyrimidines while highlighting the impact on reduced hospitalization rates.Pharmacists are central figures in leveraging DPYD genotyping for optimized patient outcomes,including dose adjustments and vigilant monitoring. This approach not only enhances treatment safety but also offers notable cost savings, with the NCCN now recommending pre-treatment DPYD genotyping. Read more on this significant progress in cancer care available at News Directory 3. Discover what’s next in personalized chemotherapy.
DPYD Genotyping Improves Fluoropyrimidine Safety and Reduces Costs
Updated May 30, 2025
New data presented at the 2025 American Society of Clinical Oncology (ASCO) meeting highlights the importance of DPYD genotyping in optimizing fluoropyrimidine (FP) chemotherapy. Studies from atrium Health Levine cancer Institute show that pre-treatment DPYD testing improves clinical outcomes and reduces costs.
Fluoropyrimidines, like 5-FU and capecitabine, are standard treatments for gastrointestinal and other solid tumors. However, 3% to 8% of patients have DPYD gene variants that impair DPD enzyme activity, increasing the risk of severe toxicity. Despite this, routine pre-treatment DPYD genotyping has been slow to gain traction due to cost and logistical concerns. The ASCO data addresses these challenges, supporting the integration of DPYD testing into oncology workflows.
Grace Nguyen, a clinical pharmacogenomics specialist at Atrium Health Levine Cancer Institute, presented a study evaluating 49 patients with DPYD variants. All patients received genotype-guided FP dosing. the study found that while initial dose reductions were common, many patients required individualized dose escalations. Patients with no-function variants experienced higher toxicity rates.
sarah Morris, also a clinical pharmacogenomics specialist at Atrium Health Levine Cancer Institute, led a cost analysis of routine DPYD genotyping. The analysis compared pre-treatment genotyping with dose adjustments to no pre-treatment testing.The study found that DPYD testing reduced per-patient costs by an average of $36.98, primarily by avoiding hospitalizations. Hospitalization rates among variant carriers decreased substantially with genotype-guided dosing.
Pharmacists play a crucial role in DPYD testing, including patient identification, dose optimization, toxicity monitoring, and advocacy. Nguyen emphasized the need for real-time clinical decision support tools to empower pharmacists.
“Pharmacists play a central role in ensuring these dose adjustments, when appropriate, are timely, safe, and evidence-based,” Nguyen said.
What’s next
The NCCN updated its guidelines on April 23, 2025, to recommend pre-treatment DPYD genotyping for patients starting fluoropyrimidine chemotherapy. This reflects a growing consensus on its clinical utility and positions pharmacists at the forefront of personalized chemotherapy approaches.