Scientific evidence demonstrating the clinical impact and benefits of pharmacogenomic testing in real patients.
Patients on Gene-Affected Meds
At least one drug impacted by genetics
Adverse Event Reduction
With PGx-guided prescribing
Annual Healthcare Savings
Per patient with PGx testing
University of Florida • 1,944 patients • Randomized controlled trial
Largest randomized controlled trial of preemptive pharmacogenomic testing in diverse patients. Participants were tested for 13 pharmacogenes (CYP2D6, CYP2C19, CYP2C9, SLCO1B1, and others) before starting medications.
27%
Reduction in Adverse Drug Reactions
Compared to standard care group
42%
Reduction in Hospitalizations
For medication-related issues
The study demonstrated that 99% of participants had at least one actionable pharmacogenetic variant. Physicians changed medication choices or doses in 41% of cases after reviewing genetic results, leading to significantly better outcomes and fewer side effects.
Published: Journal of the American Medical Association (JAMA) • Citation: Elliott LS, et al. JAMA. 2020;324(11):1110-1122
Mayo Clinic • 6,944 patients • Pre-emptive testing
Mayo Clinic's RIGHT (Right Drug, Right Dose, Right Time) protocol tested patients preemptively for CYP2D6, CYP2C19, CYP2C9, SLCO1B1, and VKORC1. Results were integrated into electronic health records with automated clinical decision support.
99.8%
Had Actionable Variant
At least one gene affecting medications
30%
Reduced Hospital Stays
Compared to historical controls
Implementation of pharmacogenomic testing resulted in medication changes for 1,103 patients (16% of those tested). The study showed significant improvements in depression outcomes for patients on antidepressants when medications were chosen based on genetic results.
Published: Genetics in Medicine • Citation: Bielinski SJ, et al. Genet Med. 2018;20(12):1488-1494
St. Jude Children's Research Hospital • 1,181 pediatric cancer patients
All pediatric cancer patients receiving 5-fluorouracil or capecitabine chemotherapy were screened for DPYD gene variants before treatment. Patients with variants received reduced starting doses (25-50% reduction based on variant type).
85%
Reduction in Severe Toxicity
In DPYD variant carriers
0
Deaths from 5-FU Toxicity
After implementing screening
Before DPYD testing was implemented, 5-10% of patients with DPYD deficiency experienced life-threatening toxicity, and approximately 0.5-1% died from treatment complications. After mandatory DPYD testing and dose adjustments, severe toxicity was virtually eliminated while maintaining cancer treatment effectiveness.
Published: Journal of Clinical Oncology • Citation: Amstutz U, et al. J Clin Oncol. 2018;36(24):2454-2462
Multi-Center Canadian Study • 2,488 patients • Clopidogrel genetic testing
Patients undergoing coronary stent placement were tested for CYP2C19 loss-of-function variants. Poor metabolizers (*2/*2, *2/*3, *3/*3) were switched from clopidogrel to ticagrelor, a non-genetic alternative antiplatelet.
91%
Reduction in Stent Thrombosis
In CYP2C19 poor metabolizers
34%
Reduced Major CV Events
Heart attack, stroke, CV death
This trial provided definitive evidence that genotype-guided antiplatelet therapy after stent placement significantly reduces major cardiovascular events. The FDA now includes CYP2C19 testing recommendations in clopidogrel's prescribing information. About 25% of patients carry loss-of-function variants.
Published: The Lancet • Citation: Claassens DMF, et al. Lancet. 2019;394(10197):1629-1638
Multi-Center • 1,167 patients • Depression treatment
Randomized controlled trial in patients with major depressive disorder. One group received pharmacogenomic-guided treatment (testing CYP2D6, CYP2C19, and other genes), while the control group received standard treatment without genetic testing.
15.3%
Higher Response Rate
At 8 weeks vs. standard care
30%
Higher Remission Rate
Complete symptom resolution
Patients in the pharmacogenomic-guided group were 1.71 times more likely to achieve remission by 24 weeks. They also experienced fewer side effects and medication changes. The study demonstrated that genetic testing significantly improves antidepressant selection and outcomes.
Published: American Journal of Psychiatry • Citation: Greden JF, et al. Am J Psychiatry. 2019;176(6):422-433
7 European Countries • 6,944 patients • Pre-emptive panel testing
The largest European pharmacogenomics implementation study. Patients across 7 countries received pre-emptive testing for 12 genes and 50 drugs. Clinical decision support tools alerted physicians when prescribing medications affected by patient genetics.
37%
Reduction in Adverse Events
Clinically relevant drug reactions
€4,382
Annual Cost Savings
Per patient tested
The study demonstrated that pharmacogenomic testing is highly cost-effective, paying for itself within the first year through reduced hospitalizations and emergency visits. The research showed that implementing routine PGx testing across healthcare systems is both clinically beneficial and economically viable.
Published: The Lancet • Citation: Swen JJ, et al. Lancet. 2023;401(10385):1161-1170
Fewer Adverse Drug Reactions
27-50% reduction in side effects and complications
Better Treatment Outcomes
30-71% higher remission rates for depression
Faster Time to Effective Treatment
Less trial-and-error, quicker symptom relief
Prevention of Life-Threatening Events
85-91% reduction in severe toxicity for high-risk drugs
Reduced Hospitalizations
30-42% fewer medication-related hospital admissions
Lower Healthcare Costs
$4,000+ annual savings per patient
Cost-Effective Investment
Testing pays for itself within 1 year
Fewer Medication Changes
Reduced need for multiple medication trials
What decades of pharmacogenomics research has taught us
Have Actionable Variants
Nearly everyone has genes affecting medications
Medications Affected
Common drugs with genetic guidance available
Evidence Quality
Multiple randomized controlled trials confirm benefit
Regulatory Support
300+ drug labels include genetic information
Clinical Guidelines
Expert consensus on gene-drug pairs
Test for Life
Your genes don't change - test once, use forever
Multiple large-scale, randomized controlled trials have demonstrated that pharmacogenomic testing improves patient outcomes, reduces adverse events, and saves healthcare costs. This isn't experimental medicine—it's evidence-based precision medicine that works today.