Infectious disease PGx.
Know your gene-drug risks. A gene panel for antiviral and antifungal medications, including the HLA-B*5701 check recommended before abacavir. One saliva sample, run in our CLIA-certified lab, with results your prescriber can refer back to.
- One sample, no blood draw
- Results in 3–7 business days
- Share with any prescriber
Panel
4 genes · CYP2B6, CYP2C19, CYP3A4, HLA-B*5701
Sample
Saliva or cheek swab
Results
3–7 business days
Price
From $289
What we test
Panel medications.
See how your genes may affect your response to certain medications. Review your results with your prescriber.
Abacavir — HLA-B*5701
Carriers of HLA-B*5701 are at high risk of a severe, potentially life-threatening hypersensitivity reaction. Guidelines recommend testing before this HIV medication is prescribed.
Efavirenz, nevirapine — CYP2B6
Slow CYP2B6 metabolizers reach higher levels, which raises the risk of dizziness, vivid dreams and central-nervous-system side effects.
Voriconazole — CYP2C19
Metabolizer status strongly changes voriconazole levels — poor metabolizers risk toxicity, rapid metabolizers may fall below the therapeutic range.
Ketoconazole — CYP3A4
Levels of this antifungal depend on CYP3A4 metabolism.
Who this is for
Genes affect drug levels and the risk of severe hypersensitivity reactions.
Starting HIV therapy
The HLA-B*5701 check belongs before abacavir is ever taken, not after a reaction.
Side effects on efavirenz or nevirapine
CYP2B6 status explains many of the central-nervous-system side effects.
Starting a systemic antifungal
Voriconazole dosing is one of the most genotype-sensitive in infectious disease.
Is this test right for you?
You are about to start abacavir or another HIV medication.
You take efavirenz or nevirapine and have had side effects.
You are starting voriconazole for a fungal infection.
A previous antiviral or antifungal did not work as expected.
You had a hypersensitivity reaction to a medication before.
Your infectious disease provider suggested genetic testing.
Answering yes to even one of these is a good reason to test before the next prescription change.
Before you order
Total price
From $289
One-time price, shown in full at checkout before you pay. No separate fee for the kit, return shipping or the healthcare provider order.
What's included
Kit to report
A saliva or cheek-swab kit with instructions, a prepaid return label, the healthcare provider order, genetic testing in our lab and a gene-drug report in your secure portal.
Who orders the test
A licensed healthcare provider
A licensed healthcare provider in our network reviews your request and places the order during checkout, at no extra cost. No referral needed.
Who reviews the results
A board-certified geneticist
Every report is reviewed and signed in our lab by a board-certified molecular geneticist before it is released.
The science
What the evidence says about getting tested.
Infectious-disease therapy contains two of the best-documented pharmacogenetics stories in medicine. HLA-B*5701 screening before abacavir effectively eliminated immunologically confirmed hypersensitivity reactions in the landmark PREDICT-1 trial, and it is now standard of care. Voriconazole levels, meanwhile, swing severalfold with CYP2C19 status — enough that poor metabolizers risk toxicity and rapid metabolizers can drop below the therapeutic window.
0
immunologically confirmed abacavir hypersensitivity cases occurred in the PREDICT-1 trial's screened group — screening worked.
Source: PREDICT-1 trial, NEJM 2008
≈6%
of people of European ancestry carry HLA-B*5701 — the reaction-risk marker checked before abacavir.
Source: PREDICT-1 trial, NEJM 2008
3–7×
higher voriconazole exposure in CYP2C19 poor metabolizers compared with normal metabolizers.
Source: CPIC voriconazole guideline
Up to 2×
higher efavirenz levels in slow CYP2B6 metabolizers — the main driver of vivid dreams and CNS side effects.
Source: CYP2B6 pharmacogenetics literature
How often should you test?
Test once — your genotype doesn't change, and for abacavir the screen belongs strictly before the first dose. For voriconazole and efavirenz, the result matters at treatment start or whenever side effects or poor response appear.
References
- Mallal S, Phillips E, Carosi G, et al. HLA-B*5701 screening for hypersensitivity to abacavir. New England Journal of Medicine. 2008;358(6):568–579.
- CPIC — Clinical Pharmacogenetics Implementation Consortium guideline for CYP2C19 genotype and voriconazole dosing.
- U.S. National Library of Medicine, DailyMed — efavirenz prescribing information: central-nervous-system side effects.
- NIH — Guidelines for the use of antiretroviral agents in adults and adolescents with HIV (HLA-B*5701 screening).
Population data
How common is each metabolizer type?
Published population frequencies for the cytochrome P450 enzymes read on this panel. Your report places you in one of these groups for each enzyme.
| Cytochrome | Poor metabolizer | Intermediate metabolizer | Normal metabolizer | Rapid or ultra-rapid metabolizer |
|---|---|---|---|---|
| CYP2D6 | 4–7% | 9–35% | 50–90% | 2–3% |
| CYP2C9 | 3% | 30% | 68% | N/A |
| CYP2C19 | 2–20% | 24–36% | 14–44% | 30% |
Population frequencies compiled from CPIC guidelines and FDA pharmacogenomic biomarker tables; frequencies vary by ancestry.
Clopidogrel — when guidelines say test
ACCF/AHA acute-coronary-syndrome guidance considers CYP2C19 testing case by case, especially after a recurrent event while on clopidogrel. CPIC recommends an alternative antiplatelet when at least one decreased-function CYP2C19 allele is present, and closer bleeding monitoring for increased metabolizers.
Warfarin — genotype-guided dosing
CPIC publishes a dosing algorithm that combines VKORC1 and CYP2C9 genotypes with clinical factors to estimate the safest starting dose, because warfarin's narrow therapeutic window makes trial-and-error dosing risky.
Statins — the SLCO1B1 check
With at least one reduced-function SLCO1B1 allele, CPIC recommends a reduced simvastatin dose or an alternative statin, since higher drug exposure raises the risk of muscle toxicity.
Voriconazole — CPIC dosing guidance
CPIC recommends an alternative agent for CYP2C19 rapid and ultra-rapid metabolizers, because therapeutic levels may never be reached, and for poor metabolizers, because levels climb into the toxic range. The difference matters most in time-critical infections such as invasive aspergillosis.
How widespread is gene-affected prescribing?
More than 250 medicines list pharmacogenomic information in their FDA-approved labeling, and one study estimated 63% of adults and 29% of children with pharmacy coverage had been prescribed at least one gene-affected medication (Liu et al., 2021).
Questions people actually ask
Screen before the first dose.
One sample, one flat price, a report your prescribers can refer back to.