Monday, July 6, 2020

PharmVar GeneFocus paper for CYP2C19 is published

The PharmVar GeneFocus: CYP2C19 paper, the second of the GeneFocus series, has just been published by Clinical Pharmacology & Therapeutics.
PharmVar thanks all CYP2C19 experts as well as the PharmGKB team who have served on this panel and diligently curated this gene and reviewed submissions ever since PharmVar was launched back in 2017. This review provides a general overview of CYP2C19 as well as a deeper dive into the nomenclature.
The GeneFocus also provides a summary of a revision of CYP2C19*1. This revision was introduced to apply PharmVar allele definition criteria consistently across all CYP2C19 haplotypes, as well as to align definitions with the current reference sequence and its recently released LRG. Highlights of the revision include:
·       All but one *1 suballele contained g.80161A>G (I331V), which posed a conflict as this SNP is also present on many other star alleles 
·       To resolve this conflict, *1.001 (previously known as *1A) was revised to *38
o   This haplotype matches the NG_008384.3 RefSeq and LRG_584; therefore, there are no SNVs in the *38 core allele definition
o   All remaining *1 subvariants now contain g.80161A>G (I331V); consequently, g.80161A>G (I331V) has been added to the *1 core allele definition
·       *1 subvariants (with g.80161A>G (I331V)) are more commonly observed than *38
o   Commonly used genotyping platforms do not test for g.80161A>G (I331V) and thus, *1 will be assigned by default
·       The I331V amino acid change does not appear to impact function; therefore, both *1 and *38 are normal function
Changes such as the update from CYP2C19*1.001 to *38 may be viewed as ‘interruptive’. However, having standardized nomenclature that is consistently applied will greatly benefit the research and clinical PGx communities moving forward. The revision can now be found on the PharmVar page for CYP2C19.

Thursday, June 11, 2020

LCD announces coverage for PGx testing under Medicare

The Centers for Medicare and Medicaid Services (CMS) have posted a FUTURE Local Coverage Determination (LCD) for MolDX: Pharmacogenomics Testing (L38294). This includes broad coverage for pharmacogenomic testing to go in effect this summer.

CPIC provided presentations to Palmetto prior to their draft LCD, and provided written comments on LCD ID L38294 back in November of 2019. CPIC members were instrumental in the feedback provided, and many of CPIC’s suggestions have been incorporated, and CPIC guidelines are cited throughout their document. For example, their post states:  “PGx tests are indicated when medications are being considered for use (or already being administered) that are medically necessary, appropriate, and approved for use in the patient’s condition and are known to have a gene(s)-drug interaction that has been demonstrated to be clinically actionable as defined by the FDA (PGx information required for safe drug administration) or Clinical Pharmacogenetic Implementation Consortium (CPIC) guidelines (category A and B).”

The LCD defines ‘actionable use’ of PGx as “when the genotype information may lead to selection of or avoidance of a specific therapy or modification of dosage of a therapy. The selection, avoidance, or dose change must be based on the FDA-label for the drug, an FDA warning or safety concern, or a CPIC level A or B gene-drug interaction”. PharmGKB uses the ‘Alternate Drug’ and ‘Dosing Info’ tags to highlight drug label annotations where the label contains information about contraindications or dosing changes based on genotype information. These tags can be used to filter our table of drug label annotations.

Monday, June 8, 2020

PGRN Transition

After 20 years of NIH funding, the Pharmacogenomics Research Network (PGRN) is becoming an independent scientific society on July 1, 2020. The deadline for becoming a founding member has been extended. If you are interested in joining, please visit

On behalf of all of the NIH PGRN funded investigators, we thank NIH for their past support, particularly our original program officer, Dr. Rochelle Long (NIGMS Director, Division of Pharmacology, Physiology and Biological Chemistry).

Update 6/29/2020 The inaugural Research In Progress (RIPS) webinar from the PGRN society will be given by Alan Shuldiner, MD, on Friday July 17 at 11am Eastern time. Dr. Shuldiner will speak on "Building bridges between industry, academia, health care systems and communities to advance Precision Medicine".

From Friday August 14, RIPS webinars will be held on the second Friday of every month at 11am Eastern time for all PGRN members. A schedule of upcoming RIPS webinars can be found here. If you are interested in joining the PGRN, you can become a member at

Friday, May 29, 2020

Dr. Stuart Scott joins Stanford

We are pleased to announce that Dr. Stuart Scott will be joining Stanford University as a Professor in the Department of Pathology effective 1 September 2020. In addition, Dr. Scott will be Laboratory Director of the Stanford Medicine Clinical Genomics Program. Dr. Scott is moving from the Department of Genetics and Genomic Sciences at the Icahn School of Medicine at Mount Sinai and Sema4 (previously the Mount Sinai Genetic Testing Laboratory). He is certified by the American Board of Medical Genetics and Genomics in both Clinical Molecular Genetics and Clinical Cytogenetics and Genomics. Dr. Scott’s research interests include pharmacogenomics (PGx), cytogenomics, epigenomics, and the implementation of genomic medicine. He has long standing collaborations with Stanford’s multi-institutional efforts in PGx including PharmGKB, CPIC, PharmVar and PharmCAT.

Tuesday, May 26, 2020

DPYD goes live on PharmVar

PharmVar has announced the introduction of DPYD to its database. DYPD is the rate limiting enzyme involved in the catabolism of fluoropyrimidines (5-fluorouracil and capecitabine) which are used in several cancer treatment regimens. Clinical laboratories provide preemptive DPYD genotyping to avoid potentially life-threatening toxicity in patients carrying DPYD risk alleles. Annotations of clinical guidelines for DPYD are available on PharmGKB here.

Prior to its introduction to PharmVar, there was no centralized resource for DPYD nomenclature. Some of the allelic variants were assigned star allele numbers when first published (DPYD*1-*13) or were referred to by a trivial name.

Although star nomenclature based on haplotypes was initially used to name DPYD variants, this system was deemed impractical for DPYD due to the size of the gene and recombination between exons. To accommodate DPYD (and other genes with similar challenges in the future), PharmVar has developed a gene page format using rsIDs as PharmVar names instead of star allele designations.

Check out the new DPYD page at PharmVar welcomes any feedback and encourages DPYD submissions to grow its inventory.

Monday, May 18, 2020

PharmGKB response to the FDA Table for Pharmacogenetic Associations

In February, the FDA posted the Table for Pharmacogenetic Associations (PGx Table), and PharmGKB and CPIC blogged about the table a few days later.  We identified substantial areas of overlap and some differences between the gene-drug pairs listed on the FDA table and those with published CPIC guidelines. It is important to note that the FDA PGx Table, CPIC, and PharmGKB may update their content at any time. These comments reflect the PGx table as of May 2020,

As of the current posting, the evidence the FDA used to construct the PGx Table is not explicitly posted, although most of the gene-drug pairs with therapeutic management recommendations on the PGx Table have labels also listed on FDA’s Table of Pharmacogenomic Biomarkers in Drug Labeling (Biomarker Table) containing some kind of prescribing information as defined by PharmGKB. The CPIC process for creating guidelines has been published and involves field experts conducting extensive reviews of the peer-reviewed literature, all of which is cited or listed as supporting evidence in the guideline publications.

Direct comparison of which gene-drug pairs have CPIC guidelines versus which are listed on the FDA PGx Table is difficult due to the completely different manners in which the pairs are selected and ranked, as well as the different content and purposes of CPIC and the FDA PGx Table. 

Here we present our compilation tables of the gene-drug pairs on FDA’s PGx table with CPIC gene-drug pairs (some of which have guidelines, some are pending, and some are not considered actionable), PharmGKB annotations of drug labels found on FDA’s Biomarker Table, PharmGKB clinical annotations, and PharmGKB annotations of clinical guidelines published by several groups, including CPIC.  These tables are updated manually and therefore may not be current with recent changes in clinical guidelines, the FDA Biomarker Table or PharmGKB clinical annotations at the time of download.

This blog post has also been submitted as a comment to the open docket at FDA.

Friday, May 1, 2020

Announcing Dr. Kelly Caudle as co-PI of CPIC

CPIC is pleased to announce that Dr. Kelly Caudle (St. Jude Children’s Research Hospital) joins Dr. Teri Klein (Stanford University) as the co-Principal Investigator of the NHGRI U24 grant (HG 010135) that provides funds for CPIC.

Dr. Caudle has been the CPIC Coordinator/Director for CPIC for 8 years. During this time she has overseen the CPIC guideline development for 22 CPIC guidelines and 13 guideline updates and has led several CPIC projects. We thank Dr. Mary Relling for her outstanding leadership and we are thrilled that she continue her involvement in CPIC as a co-Investigator at SJRCH.

Congratulations, Dr. Caudle!

Wednesday, April 29, 2020

Join the new PGRN society!

After 20 years of NIH funding, the Pharmacogenomics Research Network (PGRN) is transitioning to an independent, nonprofit scientific society, and all interested individuals are invited to sign up to become a member of the new PGRN!  The independent scientific society will continue many of the functions of the current PGRN, and we encourage you to join today to stay involved.  Benefits of joining the new PGRN include:
         Reduced registration fees for PGRN meetings and workshops, including member receptions and poster sessions at annual meetings with large scientific societies such as ASHG and ASCPT
         Participation in member calls/webinars and Research in Progress Seminars
         Membership on PGRN program committees for meetings and workshops
         Network with colleagues and establish collaborations
         Leadership opportunities for members (e.g., serve on PGRN committees, board, and as leaders)
         Awards for trainees and mentorship opportunities
         Access to PGRN web pages highlighting pharmacogenomics tools and resources, events and other useful information for PGx research, education and clinical practice

Special membership rates are available for trainees, multi-year memberships, early sign ups and those from developing countries. In addition, take advantage of the opportunity to be listed on the PGRN website as a founding member if you choose that option during signup. Sign up today at

Friday, April 17, 2020

Therapeutic Resource for COVID-19

PharmGKB has assembled a COVID-19 webpage containing therapeutic drugs from clinical trials and adjuvant therapies linking to PharmGKB annotations of gene and variant associations with these drugs.  While no trials currently discuss pharmacogenomics directly, some drugs have known associated genes and pathways.  Due to the potential QT-prolonging action of some of the drugs on this list, such as hydroxychloroquine, and the risk of concomitant treatment with other QT-prolonging agents, we have included a list of drugs associated with QT prolongation.  Additionally, we provide a list of antidepressants with Clinical Pharmacogenetic Implementation Consortium (CPIC) prescribing guidelines in light of the likelihood of depression and/or anxiety associated with the impact of COVID-19.

Following a drug link on the PharmGKB COVID-19 webpage takes the user to PharmGKB annotations about that drug, including FDA-approved drug labels, variant and clinical annotations based on peer-reviewed literature and pharmacokinetic and/or pharmacodynamic pathways.  This resource is under development.  The COVID-19 space is changing rapidly and new clinical trials continue to be added for investigational drugs, some of which are being repurposed and some of which are experimental with very limited information.  We will update the PharmGKB webpage as we get new information. 

Monday, April 13, 2020

National COVID-19 daily health survey launched by Stanford Medicine

Stanford Medicine researchers have released a daily survey to help predict surges of COVID-19 cases in the United States.

The Stanford Medicine National Daily Health Survey initially takes two minutes to complete, with subsequent daily surveys taking only seconds. It is hoped that data from the survey, in combination with local testing results, will be able to warn healthcare providers of sudden increases in COVID-19 cases in the community before those cases reach the hospital.

Speaking to Stanford Medicine, Lawrence “Rusty” Hofmann, MD, professor and chief of interventional radiology, who is leading the survey, emphasized the need for a many people as possible to participate in the survey. “To work, this survey needs people. My hope is that people see taking this survey as their civic duty and as a way to be involved in fighting COVID-19.”

“It’s crucial to continue to take the survey every day, especially during this time of uncertainty and while we shelter in place,” Hofmann told Stanford Medicine. “But even after this initial phase is over, there will be pockets of COVID-19 cases that crop up, which is why it’s important to make a habit of it and stay consistent.”

We encourage all PharmGKB users based in the US to get involved at and spread the word to colleagues, friends and family.

Wednesday, March 25, 2020

New CPIC Guideline: CYP2C9 and Nonsteroidal Anti-inflammatory Drugs (NSAIDs)

The CPIC Guideline for CYP2C9 and Nonsteroidal Anti-inflammatory Drugs (NSAIDs) is now published in Clinical Pharmacology and Therapeutics. The accepted article can be accessed on the PharmGKB pages for a number of NSAIDs drugs, CYP2C9, and on the CPIC website.

Nonsteroidal Anti-inflammatory Drugs (NSAIDs) are among the most commonly prescribed drugs to treat pain and inflammation. The main therapeutic effect of NSAIDs occurs via inhibition of prostaglandin biosynthesis mediated by the cyclooxygenases (COXs). Most NSAIDs are reversible inhibitors of both the COX-1 and COX-2 isoforms. Celecoxib, meloxicam, and diclofenac are selective inhibitors of COX-2. Hepatic metabolism by cytochrome P450 isoforms CYP2C9, 1A2, and 3A4, and renal excretion are the principal routes of clearance of the majority of NSAIDs.  Genetic variants in CYP2C9 (eg. CYP2C9*2 and *3), along with other genetics and clinical factors, have been shown to affect systemic plasma concentrations of NSAIDs and potentially safety. Patients with CYP2C9 decreased or no function alleles may have elevated exposure and at increased risk for adverse effects. 

The CPIC guideline summarizes evidence from the literature and provides therapeutic recommendations for a number of NSAIDs (celecoxib, flurbiprofen, ibuprofen, lornoxicam, meloxicam, piroxicam and tenoxicam) based on CYP2C9 genotype.    For therapeutic recommendations and further details, please refer to the CPIC Guideline for CYP2C9 and Nonsteroidal Anti-inflammatory Drugs (NSAIDs).

Monday, March 23, 2020

Lamotrigine pathway published in Pharmacogenetics and Genomics

The PharmGKB lamotrigine pathway has been recently published in the journal Pharmacogenetics and Genomics.

The publication, written by Taraswi Mitra-Ghosh, now at Auburn University, and Samuel Callisto of the Univeristy of Minnesota along with collaborators, including former PharmGKB Scientific Curator Julia Barbarino, reviews both the pharmacokinetics and pharmacodynamics of lamotrigine. Lamotrigine is an antiseizure drug which has also been approved for the treatment of bipolar disorder. It is extensively metabolized in the liver primarily by UGT enzymes. Although the exact pharmacodynamic effects of lamotrigine remain unclear, it is thought that it may act as an antagonist of voltage-gated sodium channels and voltage-gated calcium channels.

Adverse reactions, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported in patients treated with lamotrigine. A number of alleles at the HLA locus which have been linked to lamotrigine-related adverse events are also reviewed in this paper.

The pathway, including a clickable image, is also freely available on the PharmGKB website.

Sunday, February 23, 2020

FDA releases tables on the use of pharmacogenetic testing for specific medications

CPIC and PharmGKB applaud the release of additional guidance from the FDA on the use of pharmacogenetic testing for specific medications. Numerous members of the pharmacogenetics implementation community have asked CPIC and PharmGKB for our views on the FDA release and we identify some similarities and differences below.

There are substantial areas of overlap in those gene/drug pairs that CPIC/PharmGKB and FDA consider clinically actionable. There are also a few discordances between FDA’s table and CPIC guidelines and CPIC’s classification of gene/drug pairs as level A or B (i.e. clinically actionable). For example, CPIC recommends avoiding phenytoin for phenytoin-na├»ve patients with HLA-B*15:02, while phenytoin is not listed yet on the FDA tables. There are also instances in which the FDA’s table states “Refer to FDA labeling for specific dosing recommendations,” but the FDA label doesn’t include specific guidance on how much to reduce dosage or provide explicit dosing recommendations (e.g. azathioprine), information which CPIC guidelines often provide.

PharmGKB clinical annotations are based on the evaluation of published literature.  CPIC guidelines are based on evidence which is referenced in detail as part of each guideline, with expert evaluation of published literature that supports (or refutes) prescribing recommendations. At this time, it is not clear what evidence has been used by FDA to construct their tables of recommendations. It would be informative to include citations to evidence supporting these FDA tables of associations for use by others in the community.

CPIC and PharmGKB are evaluating the recent tables provided by the FDA to identify the differences between these tables and the content of the PharmGKB clinical annotations, PharmGKB annotations of the labels on the FDA Biomarker table, and CPIC guidelines.  

CPIC and PharmGKB look forward to continuing to work with the FDA and the scientific community to provide evidence-based pharmacogenetic prescribing guidelines.

Monday, February 10, 2020

Centralized presentation material repository now available from CPIC’s PGx Dissemination working group

The CPIC’s PGx Dissemination working group has developed a central repository for pharmacogenomic-related presentation materials.  Now available on the PGRN website (, users will find a resource link “discussion forum” at The discussion forum provides a medium to disseminate links to PGx presentation materials and handouts.
If you have a resource that you would like to share, please visit the site.
The PGRN does not have a central server for storage of materials. Therefore, the materials must be stored external to the PGRN and contributors must provide an active link to the material(s).
You do not need to be a PGRN member to view or post to the forum. However, forum registration is required for posting materials.
The PGx Dissemination working group hopes that you will be able to contribute to building the resource and feel free to utilize the contributions of your colleagues. If you have any questions please email The group looks forward to seeing your contributions!

Tuesday, January 21, 2020

PharmGKB and CPIC support H.R. 3235 (updated 1/27/20)

PharmGKB and CPIC have signed up as supporters of H.R. 3235, the ‘Access to Genetic Counselor Services Act’. This bill would improve access to genetic counseling for Medicare beneficiaries by recognizing genetic counselors as independent healthcare providers who can be reimbursed for their services.

Dr. Teri Klein, co-PI of PharmGKB and CPIC, said: “Genetic counselors are vital in bringing pharmacogenomics to the clinic and helping patients to understand how their genetics can affect how they respond to drugs. By supporting H.R. 3235, we hope that many more patients will be able to access these services and receive expert advice about their genetic conditions”.

More information about H.R. 3235 can be found on the website.

Update 1/24/20 Comment from Dr. Teri Klein, co-PI of PharmGKB and CPIC: "For further clarification, genetic counselors are vital in bringing genomic medicine to the clinic of which pharmacogenomics is an important component."

Update 1/27/20 Comment from Julie Johnson, PharmD, Dean and Distinguished Professor, University of Florida College of Pharmacy; Founding Director, UF Health Precision Medicine Program and CPIC Steering Committee member: "I fully support qualified health professionals, who are important members of the healthcare team, being recognized with provider status.  Two key groups that are seeking such status are genetic counselors and pharmacists.   Genetic counselors are important team members for delivering genetic/genomic medicine and it is appropriate that they should be considered for provider status.  However, I believe that PharmGKB and CPIC’s initial quote about the vital role of genetic counselors in pharmacogenetics is overstated.  Based on my nearly decade-long experience leading the clinical use of pharmacogenetics data in our health system, it has become clear that the pharmaco- part of pharmacogenetics is what makes it difficult.  Genetic data often tell us that a drug or dose is not right for a given patient, but a program is ineffective if it stops there.  Guidance must also be provided on the alternative drug or dose that is right for that patient, and this requires expert knowledge in pharmacology, pharmacokinetics and pharmacotherapy.  It is the rare genetic counselor that would be an expert in these things.  Rather the members of the healthcare team best equipped for being “vital in bringing pharmacogenomics to the clinic and helping patients to understand how their genetics can affect how they respond to drugs” are pharmacists and those physicians who possess solid foundational knowledge in clinical pharmacology.  This is not to diminish the important role of genetic counselors in patient care, but rather to say that the basis for them receiving provider status cannot be the role they play in clinical pharmacogenetics.  If the focus is a highly effective healthcare team, then the members of the team must be included based on their expertise.  In the case of clinical pharmacogenetics, those experts are most likely to be pharmacists and some physicians."