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International Journal of Epidemiology logoLink to International Journal of Epidemiology
. 2019 Aug 4;49(1):23–24k. doi: 10.1093/ije/dyz123

Cohort Profile: The Right Drug, Right Dose, Right Time: Using Genomic Data to Individualize Treatment Protocol (RIGHT Protocol)

Suzette J Bielinski 1,, Jennifer L St Sauver 1,2, Janet E Olson 1,3, Nicholas B Larson 4, John L Black III 3,5, Steven E Scherer 6, Matthew E Bernard 7, Eric Boerwinkle 8, Bijan J Borah 2,9, Pedro J Caraballo 10, Timothy B Curry 3,11, HarshaVardhan Doddapaneni 12, Christine M Formea 13, Robert R Freimuth 14, Richard A Gibbs 6, Jyothsna Giri 3, Matthew A Hathcock 4, Jianhong Hu 12, Debra J Jacobson 4, Leila A Jones 3, Sara Kalla 12, Tyler H Koep 15, Viktoriya Korchina 12, Christie L Kovar 12, Sandra Lee 12, Hongfang Liu 14, Eric T Matey 3,13, Michaela E McGree 4, Tammy M McAllister 3, Ann M Moyer 5, Donna M Muzny 12, Wayne T Nicholson 11, Lance J Oyen 13, Xiang Qin 12, Ritika Raj 12, Véronique L Roger 1,16, Carolyn R Rohrer Vitek 3, Jason L Ross 15, Richard R Sharp 3,9, Paul Y Takahashi 17, Eric Venner 12, Kimberly Walker 12, Liwei Wang 14, Qiaoyan Wang 12, Jessica A Wright 3,13, Tsung-Jung Wu 12, Liewei Wang 3,18, Richard M Weinshilboum 3,18,2
PMCID: PMC7124480  PMID: 31378813

Why was the cohort set up?

Genetic modulation of drug response can cause life-threatening adverse drug reactions, increase susceptibility to drug–drug interactions and alter therapeutic effectiveness.1–3 Pharmacogenomics has the potential to immediately impact the care of patients and is a hallmark of genomic medicine worldwide. Ideally, pharmacogenomics-guided drug selection will produce optimal effects for specific indications, reduce delays in care to effective therapies, improve patient safety and reduce health care costs. Over the past decade, a large number of pharmacogenomic variants with demonstrated clinical utility have been identified and corresponding international guidelines for clinical implementation have been developed and published by the Clinical Pharmacogenetics Implementation Consortium (CPIC),4 Canadian Pharmacogenomics Network for Drug Safety (CPNDS)5 and Royal Dutch Association for the Advancement of Pharmacy Dutch Pharmacogenetics Working Group (DPWG).6 There is now general agreement that pharmacogenomics represents an area within genomic science that could have a significant positive impact on clinical medicine and, ultimately, affect every patient.

Pre-emptive sequencing of patients interrogates large numbers of pharmacogenomic variants and integrates clinically actionable results into a patient’s electronic health record (EHR) for efficient use by clinicians at the point of care. It is unknown, however, whether integration of pre-emptive pharmacogenomic data into the EHR will significantly improve patient outcomes and reduce health care costs. Therefore, the Right Drug, Right Dose, Right Time: Using Genomic Data to Individualize Treatment Protocol (RIGHT Protocol) study was designed to recruit a large group of patients for pre-emptive pharmacogenomic testing, to develop the EHR infrastructure to deliver point of care clinical decision support and to study the effects of integrating pre-emptive pharmacogenomic testing into applied clinical practice on patient outcomes. As a result of these efforts, we have recruited 11 098 patients to study pre-emptive pharmacogenomic implementation in an integrated medical system. The RIGHT cohort therefore serves as a scientific resource to broadly address the following scientific questions.

  • What are the associations between genetic variants and clinical outcomes in patients prescribed drugs known to interact with these genes? The outcomes we will investigate include therapeutic response (e.g. pain control), time to optimal therapeutic goal, number of drug and/or dose changes, health care utilization (e.g. clinic visits and hospital days), adverse drug events/toxicity (e.g. gastro-intestinal upset), and subsequent clinical events (e.g. stroke).

  • Does pre-emptive pharmacogenomic testing improve patient outcomes and reduce health care costs through optimized treatment? By comparing patients with pharmacogenomic data to pharmacogenomics-naïve patients we will test the hypothesis that pre-emptive pharmacogenomic testing reduces adverse drug events, lowers health care utilizations and costs, and improves therapeutic response, patient safety and satisfaction.

  • What clinical outcomes are associated with pharmacogenomic variants of unknown or indeterminate clinical significance or for which evidence for changes in prescribing practices is limited? A critical barrier in identifying pharmacogenomic variants that are clinically significant is the reliance on costly clinical trials that investigate a single drug or outcome. Observational studies such as the RIGHT Protocol study will provide valuable insights regarding the cost-effectiveness of identifying drug–gene interactions that result in adverse drug events and other clinically significant outcomes.

  • How does pre-emptive pharmacogenomic testing impact clinician and patient perspectives and the broad spectrum of clinical practice? Understanding the potential influence of pre-emptive pharmacogenomics in prescribing practices, as well as identifying the possible impacts to clinician and patient interactions, can elucidate risks and opportunities that support safe integration. Identifying gaps and providing education is vital to support wide-scale implementation when diffusing medical innovations.

Who is in the cohort?

Setting

Mayo Clinic is a non-profit academic medical institution with major campuses in Rochester, MN; Scottsdale and Phoenix, AZ; and Jacksonville, FL. The Mayo Clinic Health Systems has dozens of locations in MN, IA and WI. Together, these sites provide comprehensive patient care, education in clinical medicine and medical sciences, and extensive programmes in research. In 2018, Mayo Clinic provided direct care for 1.3 million people from all 50 states and 136 countries.

The Mayo Clinic Biobank is an institutional resource comprised of adult community volunteers who donated biological specimens, provided risk factor data, allowed access to EHR data for research and consented to participate in additional studies.7 To date, over 57 000 subjects have consented to participate. Since its inception, this resource has been used for more than 250 ancillary studies and has distributed over 125 000 samples. The Mayo Clinic Biobank was the source cohort for the RIGHT Protocol study, which allowed the timely recruitment of 11 098 participants with previously stored DNA samples.

Mayo Clinic EHR data are available for all Biobank participants. However, patients use different health care providers for different reasons and may change providers and health care systems over time. Therefore, the Mayo Clinic EHR may not contain complete data for all Biobank participants. However, most of the Biobank participants (82%) reside within the region captured by the Rochester Epidemiology Project (REP) medical records-linkage system. The REP is an established research infrastructure that links the health care records of persons residing in a 27-county region of southern MN and western WI (approximately 1.1 million persons in 2010).8–10 Briefly, the REP links the health care records of Mayo Clinic, Olmsted Medical Center and its satellites, Olmsted County Public Health Services, Zumbro Valley Health Center and some smaller health care providers in this region. As residents of this region visit one of the REP collaborators for health care, the REP captures the electronic data related to the health care visits. In addition, the full texts of health care records are available for abstraction for all persons in the REP system since 1966. Overall, 99% of the Biobank participants have at least one non-Mayo Clinic medical record captured by the REP. Therefore, linking the Biobank participants to the REP infrastructure provides access to more complete coverage and follow-up of the Biobank population.

Recruitment

Beginning in 2012, Biobank participants were recruited for the RIGHT pilot study, which has been previously described.11 In brief, 1013 patients consented to pharmacogenomic testing and return of pharmacogenomic results to their EHR for use in their clinical care. This pilot resulted in the infrastructure to support the expansion of the cohort. Beginning in May 2016, we began a targeted effort to further enroll an additional 10 000 persons. Patients with prior allogeneic haematopoietic stem cell transplants and/or haematologic malignancies were not eligible to participate due to the fact that circulating lymphocytes were used as the DNA source. All non-White Biobank participants (n =1442) were preferentially invited to increase the diversity of the cohort. Participants were then prioritized by those that receive the majority of their care at Mayo Clinic based on EHR length and a history of clinic visits in a primary care clinic (e.g. Internal Medicine, Family Medicine). All eligible Biobank participants were mailed an invitation to participate in the RIGHT Protocol study and a consent form. The invitation letter gave recipients three options: (i) participate in the study, (ii) decline to participate, or (iii) declare themselves ineligible because they did not intend to utilize Mayo Clinic for their future health care. Consenting RIGHT participants agreed to allow use of their stored Biobank samples for clinical pharmacogenomic testing, deposit of pharmacogenomic results into their EHR for clinical use, and use of EHR and pharmacogenomic data for research. If no response was received after a period of 4 weeks, one additional attempt was made with a second mailing. This expanded recruitment effort was completed in 16 months. Overall, 18 199 persons were approached, 56% consented to participate, 29% did not respond and 15% self-reported ineligibility or refused (Table 1).

Table 1.

Characteristics of 1013 RIGHT pilot participants and the 18 199 patients invited to participate in the expansion of the RIGHT protocol

Characteristic RIGHT expansion results
RIGHT pilot participantsa Invited Consented Did not respond Ineligible/ refused Complete RIGHT cohort
n = 1013 n = 18 199 n = 10 085 n = 5331 n = 2783 n = 11 098
Sex, n (%)            
 Female 538 (53) 11 043 (61) 6150 (61) 3192 (60) 1701 (61) 6688 (60)
 Male 475 (47) 7156 (39) 3935 (39) 2139 (40) 1082 (39) 4410 (40)
Age on January 1, 2016, years, n (%)            
 18–24 0 (0) 151 (1) 58 (1) 76 (1) 17 (1) 58 (1)
 25–34 0 (0) 1701 (9) 647 (6) 784 (15) 270 (10) 647 (6)
 35–44 2 (<1) 1722 (9) 825 (8) 744 (14) 153 (6) 827 (7)
 45–54 178 (18) 2390 (13) 1299 (13) 831 (16) 260 (9) 1477 (13)
 55–64 658 (65) 3769 (21) 2069 (21) 1138 (21) 562 (20) 2727 (25)
 65–74 175 (17) 5084 (28) 3217 (32) 1056 (20) 811 (29) 3392 (31)
 75+ 0 (0) 3382 (19) 1970 (20) 702 (13) 710 (26) 1970 (18)
Race, n (%)            
 White 966 (95) 16 759 (92) 9482 (94) 4689 (88) 2588 (93) 10 448 (94)
 Non-White 39 (4) 1177 (6) 524 (5) 492 (9) 161 (6) 563 (5)
  Black 7 (1) 124 (1) 50 (<1) 64 (1) 10 (<1) 57 (1)
  Asian 9 (1) 276 (2) 91 (1) 139 (3) 46 (2) 100 (1)
  AIAN 0 (0) 30 (<1) 16 (<1) 8 (<1) 6 (<1) 16 (<1)
  NHPI 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0)
  Other and mixed 23 (2) 747 (4) 367 (4) 281 (5) 99 (4) 390 (3)
 Unknown 8 (1) 263 (1) 79 (1) 150 (3) 34 (1) 87 (1)
Ethnicity, n (%)            
 Non-Hispanic 1006 (99) 17 906 (98) 9967 (99) 5205 (98) 2734 (98) 10 973 (99)
 Hispanic 7 (1) 275 (2) 112 (1) 115 (2) 48 (2) 119 (1)
 Unknown 0 (0) 18 (<1) 6 (<1) 11 (<1) 1 (<1) 6 (<1)
Self-reported education at time of Biobank consent (2009–2017), n (%)            
 High school graduate or General Educational Development (GED) or less 87 (9) 2754 (15) 1262 (13) 897 (17) 595 (21) 1349 (12)
 Some college or Associates degree (including community college) 326 (32) 5614 (31) 2938 (29) 1817 (34) 859 (31) 3264 (29)
 Four year college graduate (Bachelor's degree) 238 (24) 3580 (20) 1992 (20) 1079 (20) 509 (18) 2230 (20)
 Graduate or professional school 362 (36) 6116 (34) 3848 (38) 1476 (28) 792 (28) 4210 (38)
 Unknown 0 (0) 135 (1) 45 (<1) 62 (1) 28 (1) 45 (<1)
a

Previously recruited in 2012–2013.

AIAN, American Indian or Alaska Native; NHPI, Native Hawaiian or Pacific Islander.

Cohort characteristics

Table 1 summarizes the characteristics of the RIGHT pilot participants, recruitment results for the expansion of the cohort and the characteristics of the full RIGHT cohort. Table 2 compares characteristics of the RIGHT cohort, Mayo Clinic Biobank and REP 27-county populations.

Table 2.

Characteristics as of January 1, 2016 of the RIGHT cohort, Mayo Clinic Biobank and Rochester Epidemiology Project

  RIGHT cohort Mayo Clinic Biobank Rochester Epidemiology Project 27-counties
Characteristic n = 11 098 n = 56 988 n = 582 466
Sex, n (%)    
 Female 6688 (60) 33 478 (59) 309 707 (53)
 Male 4410 (40) 23 510 (41) 272 759 (47)
Age on January 1, 2016, years, n (%)      
 18–24 58 (1) 536 (1) 69 237 (12)
 25–34 647 (6) 3227 (6) 98 800 (17)
 35–44 827 (7) 4026 (7) 85 385 (15)
 45–54 1477 (13) 7238 (13) 94 059 (16)
 55–64 2727 (25) 13 020 (23) 101 644 (17)
 65–74 3392 (31) 15 115 (27) 71 216 (12)
 75+ 1970 (18) 13 826 (24) 62 125 (11)
Race, n (%)      
 White 10 448 (94) 54 316 (95) 520 716 (89)
 Non-White 563 (5) 1967 (3) 41 434 (7)
  Black 57 (1) 702 (1) 14 248 (2)
  Asian 100 (1) 572 (1) 11 423 (2)
  AIAN 16 (<1) 117 (<1) 1491 (<1)
  NHPI 0 (0) 22 (<1) 842 (<1)
  Other and mixed 390 (3) 554 (1) 13 430 (2)
 Unknown race 87 (1) 705 (1) 20 316 (3)
Ethnicity, n (%)      
 Non-Hispanic 10 973 (99) 5370 (94) 505 374 (87)
 Hispanic 119 (1) 783 (1) 22 428 (4)
 Unknown 6 (<1) 2504 (4) 54 664 (9)
Socio-economic characteristics      
  ≥ High school (%) 99 97 41*
  ≥ Bachelor’s degree (%) 58 50 15*
*

Education data are available for 329 589 (57%) persons; percentages are based on this denominator.

AIAN, American Indian or Alaska Native; NHPI, Native Hawaiian, or Pacific Islander.

How often have they been followed up?

Prospective and retrospective studies

A primary goal of the RIGHT Protocol study was to implement pre-emptive pharmacogenomics for Mayo Clinic patients. Therefore, by design, we anticipate the majority of our follow-up will be conducted passively, via the EHR, in order to estimate patient outcomes after implementation of pre-emptive pharmacogenomics. Prospective studies, defined as occurring after pharmacogenomic data were placed in the EHR, permit comparisons of the RIGHT cohort to a pharmacogenomics-naïve group to determine the effects of genotype-guided prescribing. As of January 1, 2018, 99% of the cohort was living and 85% had a clinic visit in 2017 (Table 3). The RIGHT Protocol study also enables retrospective studies by leveraging decades of drug exposures to compare drug response across genotype prior to pharmacogenomic results being placed in the EHR (pharmacogenomics-naïve time period). The median length of the medical record is 22 years for the cohort (Table 3). For either study type, outcomes can include health care utilization, drug type and dose changes, time to optimal therapy, and adverse drug events including subsequent clinical events (e.g. stent thrombosis). Finally, the availability of genetic sequence data allows for discovery of additional drug–gene interactions for which clinical evidence is limited or non-existent.

Table 3.

Medical record data for the RIGHT cohort

Characteristics RIGHT cohort
n = 11 098
Alive as of January 1, 2018, n (%) 11 021 (99)
Clinical contact in 2017, % yes 85
Length of medical record prior to 2017, median years interquartile range (IQR) 22 (19, 27)
Clinic visits per year from 2004 to 2017, median visits (IQR) 27 (16, 44)
Prescribed medications in 2017, n (%)  
 None 1010 (9)
 1–2 1725 (16)
 3–5 2732 (25)
 6–10 2992 (27)
 11–20 2124 (19)
 ≥ 21 515 (5)
Prescribed a drug with therapeutic recommendationsa 2004–2017, n (%) 
 abacavir 2 (<1)
 allopurinol 494 (4)
 amitriptyline 664 (6)
 atazanavir 1 (<1)
 azathioprine 134 (1)
 capecitabine 20 (<1)
 carbamazepine 102 (1)
 citalopram 1531 (14)
 escitalopram 524 (5)
 clomipramine 8 (<1)
 clopidogrel 636 (6)
 codeine 3704 (33)
 desipramine 20 (<1)
 doxepin 179 (2)
 fluorouracil 625 (6)
 fluvoxamine 16 (<1)
 imipramine 29 (<1)
 ivacaftor 0 (0)
 mercaptopurine 11 (<1)
 nortriptyline 723 (7)
 ondansetron 1927 (17)
 oxcarbazepine 29 (<1)
 paroxetine 369 (3)
 peginterferon alfa-2a 4 (<1)
 peginterferon alfa-2b 3 (<1)
 ribavirin 8 (<1)
 phenytoin 41 (<1)
 rasburicase 0 (0)
 sertraline 1268 (11)
 simvastatin 3562 (32)
 tacrolimus 449 (4)
 tamoxifen 180 (2)
 tegafur 0 (0)
 thioguanine 0 (0)
 trimipramine 3 (<1)
 tropisetron 0 (0)
 voriconazole 53 (<1)
a

Therapeutic recommendations are available at https://www.pharmgkb.org/guidelines

Active follow-up

Participants in the cohort may, with appropriate approvals, be contacted directly to assess pharmacogenomics-related outcomes. To date, we have conducted three surveys of RIGHT participants. The RIGHT pilot study participants were surveyed in 2014 to assess their understanding of their CYP2D6 results.12 Of those invited, 86% completed the survey.13 In 2017, 5000 subjects from the expanded cohort were surveyed after enrollment to collect information on prior testing, expectations and concerns about pharmacogenomic testing, as well as their views about their current medications and medications in general. Response to this survey was exceptionally high (94%) and reflects a very high level of interest in pharmacogenomics in our population. A follow-up survey is currently in the field to assess responses following receipt of pharmacogenomic results. Additionally, there are opportunities to study clinician perspectives, pharmacogenomic testing behaviours and clinical actions following deposition of pharmacogenomic results into the EHR.

Loss to follow-up

The recruitment design of the study prioritized patients for whom Mayo Clinic is their primary care clinic and therefore loss to follow-up is mitigated. Likewise, use of the REP allows for data capture within the surrounding community practices. However, data capture decreases as the distance of the patient’s residence from Rochester, MN increases. Loss to follow-up will occur for those patients moving or choosing a provider out of our catchment area. However, as indicated in Table 3, the RIGHT cohort reflects a stable patient population with 91% receiving at least one prescription in 2017.

What has been measured?

DNA sequencing and pharmacogenomic phenotyping

For the 1013 pilot-study participants, lymphocyte-derived DNA sequencing of 84 pharmacogenes was completed at Mayo Clinic using Version 1 (v.1) of the PGRN-Seq assay.14 For the expanded RIGHT cohort, the Clinical Laboratory Improvement Amendments (CLIA)-certified and College of American Pathologists (CAP)-accredited Baylor College of Medicine’s Human Genome Sequencing Center Clinical Laboratory sequenced 77 genes using version 3 (v.3.) of the PGRN-Seq assay (now termed PGx-seq). This panel includes structurally complex genomic regions important to optimal drug treatment including CYP2D6 and HLA regions. CYP2D6 is involved in the metabolism of 25% of the drugs currently on the market15 and HLA regions are associated with severe drug hypersensitivities (e.g. Stevens-Johnson Syndrome). In v.1, all gene coverage included all gene model exons plus both 2 kb upstream and 1 kb downstream. In v.1, targeted exons and 2 kb upstream/1 kb downstream for CYP2A6 were included. For PGx-seq, these upstream and downstream targets were dropped. In both v.1 and PGx-seq, intron 6 of CYP3A4 was targeted. In PGx-seq, the entire ∼31 kb region for CYP2D6 was targeted including both of the nearby pseudogenes. For both versions, all of the Illumina ADME and Affymetrix DMET single nucleotide polymorphism (SNP) sites not already covered by gene targets were included. Over 250 genes have either DNA sequencing or SNP genotyping information available (Table 4).

Table 4.

Genetic data available in the RIGHT study

Gene Sequence data
Genotype data
Version 1 Version 3
ABCA1 Yes No No
ABCB1 Yes Yes Yes
ABCB11 Yes No Yes
ABCB4 No No Yes
ABCB7 No No Yes
ABCC1 No No Yes
ABCC2 Yes No Yes
ABCC3 No No Yes
ABCC4 No Yes Yes
ABCC5 No No Yes
ABCC6 No No Yes
ABCC8 No No Yes
ABCC9 No No Yes
ABCG1 Yes No Yes
ABCG2 Yes Yes Yes
ABP1 No No Yes
ACAD10 No No Yes
ACE Yes No No
ADH1A No No Yes
ADH1B No No Yes
ADH1C No No Yes
ADH4 No No Yes
ADH5 No No Yes
ADH6 No No Yes
ADH7 No No Yes
ADRB1 Yes No No
ADRB2 Yes Yes No
AGR3 No No Yes
AHR Yes No Yes
AKAP9 No No Yes
ALB No No Yes
ALDH1A1 No No Yes
ALDH2 No No Yes
ALDH3A1 No No Yes
ALDH3A2 No No Yes
ALOX5 Yes No No
ANKK1 No Yes No
ANKRD17 No No Yes
ANXA1 No No Yes
AOX1 No No Yes
AOX2P No No Yes
APOA1 Yes No No
APOA2 No No Yes
ARID5B Yes No No
ARNT No No Yes
ARSA No No Yes
ASB4 No No Yes
ATP7A No No Yes
ATP7B No No Yes
ATXN7L2 No No Yes
BCKDK No No Yes
BDNF Yes No No
C14orf164 No No Yes
C16orf54 No No Yes
C18orf16 No No Yes
C1orf87 No No Yes
C3orf22 No No Yes
C4orf17 No No Yes
CACNA1C Yes No No
CACNA1S Yes No No
CACNB2 Yes No No
CBR1 No No Yes
CBR3 No No Yes
CCDC101 No No Yes
CDA No No Yes
CES1 Yes Yes No
CES2 Yes No Yes
CFTR No Yes No
CHST1 No No Yes
CHST10 No No Yes
CHST11 No No Yes
CHST13 No No Yes
CHST2 No No Yes
CHST3 No No Yes
CHST4 No No Yes
CHST5 No No Yes
CHST6 No No Yes
CHST7 No No Yes
CHST8 No No Yes
CHST9 No No Yes
COMT Yes Yes Yes
CRHR1 Yes No No
CRIP3 No No Yes
CROT No No Yes
CYP11A1 No No Yes
CYP11B1 No No Yes
CYP11B2 No No Yes
CYP17A1 No No Yes
CYP19A1 No No Yes
CYP1A1 No No Yes
CYP1A2 Yes Yes Yes
CYP1B1 No No Yes
CYP20A1 No No Yes
CYP21A2 No No Yes
CYP24A1 No No Yes
CYP26A1 No No Yes
CYP26C1 No No Yes
CYP27A1 No No Yes
CYP27B1 No No Yes
CYP2A13 No No Yes
CYP2A6 Yes Yes Yes
CYP2A7 No No Yes
CYP2B6 Yes Yes Yes
CYP2B7P1 No No Yes
CYP2C18 No No Yes
CYP2C19 Yes Yes Yes
CYP2C8 No Yes Yes
CYP2C9 Yes Yes Yes
CYP2D6 Yes Yes Yes
CYP2D7P1 No No Yes
CYP2E1 No Yes Yes
CYP2F1 No No Yes
CYP2J2 No Yes Yes
CYP2R1 Yes No No
CYP2S1 No No Yes
CYP39A1 No No Yes
CYP3A4 Yes Yes Yes
CYP3A43 No No Yes
CYP3A5 Yes Yes Yes
CYP3A7 No No Yes
CYP46A1 No No Yes
CYP4A11 No No Yes
CYP4A22 No No Yes
CYP4B1 No No Yes
CYP4F11 No No Yes
CYP4F12 No No Yes
CYP4F2 No Yes Yes
CYP4F3 No No Yes
CYP4F8 No No Yes
CYP4X1 No No Yes
CYP4Z1 No No Yes
CYP4Z2P No No Yes
CYP51A1 No No Yes
CYP7A1 No No Yes
CYP7B1 No No Yes
CYP8B1 No No Yes
DBH Yes No No
DCK No No Yes
DKFZp779M0652 No No Yes
DPYD Yes Yes Yes
DRD1 Yes No No
DRD2 Yes Yes No
DRD3 No Yes No
DRD4 No Yes No
EGFR Yes Yes No
EPHX1 No No Yes
EPHX2 No No Yes
ESR1 Yes No No
F2 No No No
F5 No Yes No
FAAH No Yes Yes
FAM19A3 No No Yes
FKBP5 Yes No No
FMO1 No No Yes
FMO2 No No Yes
FMO3 No No Yes
FMO4 No No Yes
FMO5 No No Yes
FMO6P No No Yes
G6PD Yes Yes Yes
GGCX No Yes No
GLCCI1 Yes No No
GRIK4 No Yes No
GRIP2 No No Yes
GRK4 Yes No No
GRK5 Yes No No
GSTA1 No No Yes
GSTA2 No No Yes
GSTA3 No No Yes
GSTA4 No No Yes
GSTA5 No No Yes
GSTM1 No No Yes
GSTM2 No No Yes
GSTM2P1 No No Yes
GSTM3 No No Yes
GSTM4 No No Yes
GSTM5 No No Yes
GSTO1 No No Yes
GSTP1 No Yes Yes
GSTT1 No No Yes
GSTT2 No No Yes
GSTT2B No No Yes
GSTZ1 No No Yes
HLA-A No Yes No
HLA-B No Yes No
HMGCR Yes Yes Yes
HNF1A No Yes No
HNF4A No Yes No
HNMT No No Yes
HOMEZ No No Yes
HSD11B2 Yes No No
HTR1A Yes No No
HTR2A Yes Yes No
HTR2C No Yes No
ICK No No Yes
IFNL3 No Yes No
IGFBP7 No Yes No
IL28B No No No
KCNH2 Yes Yes No
KIF6 No Yes No
LDLR Yes Yes No
LEP No Yes No
LEPR No Yes No
LOC26172 No No Yes
LOC286186 No No Yes
LOC619207 No No Yes
LOC651536 No No Yes
LOC96610 No No Yes
LST-3TM12 No No Yes
MAOA Yes No Yes
MAOB No No Yes
MAT1A No No Yes
METTL1 No No Yes
MKL1 No No Yes
MTHFR No Yes No
MYOF No No Yes
NAT1 No No Yes
NAT2 Yes Yes Yes
NNMT No No Yes
NPPB Yes No No
NPR1 Yes No No
NQO1 No No Yes
NR1I2 No No Yes
NR1I3 No No Yes
NR3C1 Yes No Yes
NR3C2 Yes No No
NTRK2 Yes No No
NTSR1 No No Yes
NUDT15 No No No
OPA3 No No Yes
OPRM1 No Yes No
ORM1 No No Yes
ORM2 No No Yes
PARL No No Yes
PCP4L1 No No Yes
PEAR1 Yes No No
PGAP3 No No Yes
PNMT No No Yes
PON1 No Yes Yes
PON2 No No Yes
PON3 No No Yes
POR Yes No Yes
PPARD No No Yes
PPARG No No Yes
PPP1R9A No No Yes
PRSS53 No No Yes
PTGIS Yes No Yes
PTGS1 Yes No No
QPRT No No Yes
RALBP1 No No Yes
RPL13 No No Yes
RXRA No No Yes
RYR1 Yes Yes No
RYR2 Yes Yes No
SCN1A No Yes No
SCN5A Yes Yes No
SDCBP No No Yes
SERPINA7 No No Yes
SETD4 No No Yes
SHANK3 No No Yes
SLC10A1 No No Yes
SLC10A2 No No Yes
SLC13A1 No No Yes
SLC15A1 No No Yes
SLC15A2 Yes No Yes
SLC16A1 No No Yes
SLC19A1 No Yes Yes
SLC22A1 Yes Yes Yes
SLC22A11 No No Yes
SLC22A12 No No Yes
SLC22A13 No No Yes
SLC22A14 No No Yes
SLC22A2 Yes Yes Yes
SLC22A3 Yes No Yes
SLC22A4 No No Yes
SLC22A5 No No Yes
SLC22A6 Yes No Yes
SLC22A7 No No Yes
SLC22A8 No No Yes
SLC25A27 No No Yes
SLC28A1 No No Yes
SLC28A2 No No Yes
SLC28A3 No No Yes
SLC29A1 No No Yes
SLC29A2 No No Yes
SLC41A2 No No Yes
SLC47A1 Yes No No
SLC47A2 Yes No No
SLC5A6 No No Yes
SLC6A3 Yes No No
SLC6A4 Yes Yes No
SLC6A6 No No Yes
SLC7A5 No No Yes
SLC7A5P1 No No Yes
SLC7A7 No No Yes
SLC7A8 No No Yes
SLC9A7 No No Yes
SLCO1A2 Yes No Yes
SLCO1B1 Yes Yes Yes
SLCO1B3 Yes No Yes
SLCO2B1 Yes Yes Yes
SLCO3A1 No No Yes
SLCO4A1 No No Yes
SLCO5A1 No No Yes
SOD2 No Yes No
SPG7 No No Yes
SPN No No Yes
SR140 No No Yes
SULT1A1 No Yes Yes
SULT1A2 No No Yes
SULT1A3 No No Yes
SULT1A4 No No Yes
SULT1B1 No No Yes
SULT1C2 No No Yes
SULT1C4 No No Yes
SULT1E1 No No Yes
SULT2A1 No No Yes
SULT2B1 No No Yes
SULT4A1 No No Yes
TBXAS1 Yes No Yes
TCL1A Yes No No
TFF3 No No Yes
TMEM120A No No Yes
TMEM176A No No Yes
TMPRSS11B No No Yes
TOP1P1 No No Yes
TP53 No Yes No
TPMT Yes Yes Yes
TPSG1 No No Yes
TSEN2 No No Yes
TTBK1 No No Yes
TYMS No Yes Yes
UGT1A1 Yes Yes Yes
UGT1A10 No No Yes
UGT1A3 No No Yes
UGT1A3-10 exon1 No Yes No
UGT1A4 Yes Yes Yes
UGT1A5 No No Yes
UGT1A6 No No Yes
UGT1A7 No No Yes
UGT1A8 No No Yes
UGT1A9 No No Yes
UGT2A1 No No Yes
UGT2A2 No No Yes
UGT2B10 No No Yes
UGT2B11 No No Yes
UGT2B15 No Yes Yes
UGT2B17 No No Yes
UGT2B28 No No Yes
UGT2B4 No No Yes
UGT2B7 No Yes Yes
UGT8 No No Yes
VDR Yes No No
VEGFA No Yes No
VKORC1 Yes Yes Yes
XDH No No Yes
XYLB No No Yes
ZNF280B No No Yes
ZNF423 Yes No No
ZNF662 No No Yes

For the RIGHT pilot, CYP2C19, CYP2C9, VKORC1, SLCO1B1 and CYP2D6, sequencing results were interpreted at the Mayo Clinic Personalized Genomics Laboratory, a CLIA-certified and CAP-accredited laboratory. These genes were chosen because they have strong clinical practice recommendations when patients are prescribed warfarin, clopidogrel, simvastatin, tamoxifen, opioid analgesics and selective serotonin reuptake inhibitors.16 For the expanded RIGHT cohort, CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A4, CYP3A5, DPYD, SLCO1B1, TPMT, UGT1A1, VKORC1, HLA-A and HLA-B are interpreted and reported in the EHR by the Personalized Genomics Laboratory. Point of care drug–gene alerts access these reports and present a description of the variants identified for each gene to the prescriber. In addition, the clinician receives an interpretation of the impact of the findings on gene function as well as pharmacogenomic implications. Table 5 includes the drug–gene alerts active in the Mayo Clinic EHR as of December 31, 2018.

Table 5.

Mayo Clinic clinical decision support interventions

Gene Drug Year went live
CYP2C19 Clopidogrel 2014
Citalopram 2015
Escitalopram 2015
CYP2D6 Codeine 2013
Tramadol 2013
Tamoxifen 2013
Paroxetine 2015
Fluoxetine 2015
Fluvoxamine 2015
Venlafaxine 2015
SLCO1B1 Simvastatin 2014
CYP2C9/VKORC1 Warfarin 2014
TPMT
Genotype or phenotype
Mercaptopurine 2013
Thioguanine 2013
Azathioprine 2013
HLA-B*1502 Carbamazepine 2013
HLA-B*5701 Abacavir 2013
HLA-B*5801 Allopurinol 2014
CYP3A5 Tacrolimus 2016
DPYD 5-FU 2017
NUDT15 Mercaptopurine 2018
Thioguanine 2018
Azathioprine 2018
HLA-A*3101 Carbamazepine 2018

A pharmacogenomic interpretive report (OneOme LLC, Minneapolis, MN) provides information to clinicians on how an individual patient's genes may affect drug response. Proprietary algorithms and curated clinical data are used to generate a personalized report based on a patient's genomic results. The report lists drugs categorized into three different bins according to genomic impact on different metabolic or physiologic effects: ‘Major gene–drug interaction’ (red), ‘Moderate gene–drug interaction’ (yellow) and ‘Minimal gene–drug interaction’ (green). The drugs are further classified by primary therapeutic area. For each drug, the report provides the patient’s results of the interpreted genes along with additional clinical annotation and interpretations in both textual and graphical form to provide clinicians with a better understanding of the complex information. These static reports flow through the Personalized Genomics Laboratory and are placed into the EHR for each patient. These reports may be viewed by health care providers, but do not interact with the EHR.

Drug prescription information

Drug prescription information is available via the REP. Complete outpatient electronic prescription data are available from January 1, 2004 through to the present. Filled drug prescription data are not available. However, medication reconciliation occurs when patients visit a health care provider. Patients are asked to list all of the medications they are currently taking, including prescribed medications, over the counter medications and supplements. All medication information is coded using the RxNorm and National Drug File-Reference Terminology (NDF-RT) coding systems.17,18 Combination drugs with multiple ingredients are counted under the category of the main ingredient, or under the combination drug category when applicable. The REP electronic indexes may be searched to identify all persons with either a prescription or report of medication use in the desired time frame. Prescriptions for drugs with pharmacogenomic guidelines for the RIGHT cohort are summarized in Table 3.

Outcomes

Relevant pharmacogenomic outcomes (e.g. response to treatment or adverse events) may be assessed electronically using coded data from the available EHRs and billing systems. Such data include all International Classification of Diseases (ICD-9 and ICD-10) and Current Procedural Terminology (CPT) coded diagnoses and procedures from these EHRs, as well as health care utilizations including hospitalizations, office visits and emergency room visits. We also maintain access to the full text of the EHRs in the REP, and this text is available for chart abstraction or for natural language processing (NLP) techniques. We have used such techniques to identify prescription drug allergies from the linked EHRs (see below).

Processed allergy section clinical notes

Drug side-effects as well as drug allergies are commonly reported in the allergy section of the clinical note. As a result, the allergy section is a rich source of information for adverse drug reactions. However, descriptions of drug events are often embedded in both structured and unstructured clinical narratives, and thus processes for cleaning and standardizing the data are required. For the RIGHT Protocol study, we deployed NLP methods to process the clinical text and annotate clinical concepts to capture adverse drug events.19–21 We used the Medical Dictionary for Regulatory Activities (MedDRA),22,23 a medical terminology ontology adopted to describe adverse drug reactions and provide an internationally approved classification, and the Unified Medical Language System (UMLS, version 2012AB) (https://www.nlm.nih.gov/research/umls/),24 a knowledge resource for biomedical vocabularies developed by the US National Library of Medicine. Allergy data from the EHR were pulled and recorded as unstructured text, for example: ‘fluid retention, hypertension’ and ‘anxiety, distorted vision’. We used MedTagger,25 an NLP pipeline to extract adverse drug events mentioned in text. The extracted descriptions were then mapped to MedDRA terms and then aggregated using UMLS. For example, in the allergy text ‘fluid retention, hypertension’, ‘fluid retention’ was first extracted and mapped to MedDRA ‘body fluid retention’, and mapped to ‘Renal and urinary disorders’ and ‘Metabolism and nutrition disorders’, whereas ‘hypertension’ was extracted and mapped to ‘Vascular disorders’. The top five most common drug reactions were skin and subcutaneous tissue disorders, gastrointestinal disorders, immune system disorders, nervous system disorders, and general disorders and administration site conditions.

EHR integration and clinical decision support

Since 2013, Mayo Clinic has developed and implemented a comprehensive multidisciplinary model26 to integrate pharmacogenomic test results and clinical decision support (CDS) interventions in the Mayo Clinic unified EHR system (Table 5). Real-time pharmacogenomic-CDS alerts advise the need for pharmacogenomic testing when it is indicated, alert for potentially actionable drug–gene interactions, explain to prescribers the nature of the drug–gene interaction, and provide patient-specific therapeutic recommendations. The rules are embedded in the clinical workflow of all prescribers and pharmacists managing prescriptions (inpatient and outpatient prescription management systems). Multiple implementation and process metrics have been developed to allow post-implementation analyses. It is possible to measure when alerts are triggered and whether the clinician changes the initial prescription following the CDS alert. Such data allow for studies of clinician behaviours related to pharmacogenomics-CDS implementation.

What has it found? Key findings and publications

In the RIGHT pilot study, we found that 99% of participants had a clinically actionable variant when considering the five genes reported in the EHR (CYP2C19, CYP2C9, VKORC1, SLCO1B1 and CYP2D6).27 We have also reported our experience with integrating pharmacogenomic-CDS alerts into clinical practice in recent publications.16,26,28

Drug-focused studies include investigating drug response and clinical outcomes associated with exposure to opioids,29 diabetes treatment, proton pump inhibitors, statins, anaesthesia, antidepressants, anticoagulants, penicillin, beta blockers and antifungals. Other ancillary studies have assessed patient and provider perspectives on pharmacogenomics.12,13,28 Finally, additional studies have examined associations between pharmacogenomic phenotypes and health care utilization.30

One of our key findings is related to our first return of results to participants. After the pilot was completed, we returned CYP2D6 results to participants and surveyed them to determine their understanding of the data. Of the respondents, 26% said that they only somewhat understood their results and 7% did not understand them at all. Participants commonly suggested that results should be personalized, should refer to drugs they were currently taking, and should use layperson language.12

What are the main strengths and weaknesses?

The strengths of the RIGHT cohort derive from the large sample size, extensive EHR data, medical record access for abstraction, ability to study any drug exposure, and availability of sequence data for discovery. The RIGHT cohort are all Mayo Clinic Biobank participants who have existing, stored biospecimens (DNA, plasma, serum, white blood cells) and who can be re-contacted for future research questions or invited to participate in ancillary studies. The ability to cost-effectively re-contact participants expands the research capability of the cohort. Despite the strengths, the RIGHT cohort has some limitations. First, the cohort was not selected from patients with any particular diagnosis or drug indication. Thus, although the RIGHT study is one of the largest studies of pre-emptive pharmacogenomics, less frequent and rare drug exposures will be difficult to study in this population. Second, because this is an observational cohort, and not a clinical trial, patients in this study have been prescribed drugs based upon prescriber practices, the dictates of insurance coverage, and not randomized methods. Thus, inferences may be limited.

Can I get hold of the data? Where can I find out more?

The RIGHT cohort is a resource for pharmacogenomic research.11 As part of the infrastructure, a RIGHT Data Access Committee has been created to review data requests for use of RIGHT data. External access to the data is facilitated by the Mayo Clinic Biobank31 https://www.mayo.edu/research/centers-programs/mayo-clinic-biobank/overview

Profile in a nutshell

  • Pharmacogenomics is the hallmark of genomic medicine worldwide.

  • 11 098 Mayo Clinic patients have consented to pre-emptive pharmacogenomic testing.

  • The RIGHT study was developed to address several goals:
    • identify the associations between genetic variants and clinical outcomes in patients prescribed drugs known to interact with these genes,
    • determine if pre-emptive pharmacogenomic testing improves patient outcomes and reduces health care costs,
    • identify clinical outcomes associated with pharmacogenomic variants of unknown or indeterminate clinical significance, and
    • understand the perspectives and practices of clinicians and patients.
  • DNA sequencing or SNP genotyping information is available for over 250 genes.

  • Decades of prescription data are available for research via the Rochester Epidemiology Project (REP) medical records-linkage system.

  • Comparisons of the RIGHT cohort to a pharmacogenomic-naïve cohort allow for the study of the effects of genotype-guided dosing.

Funding

This work was supported by the Mayo Clinic Center for Individualized Medicine, the Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, and the National Institutes of Health grants [U19 GM61388 (The Pharmacogenomics Research Network), R01 GM28157, U01 HG005137, R01 GM125633, R01 AG034676 (The Rochester Epidemiology Project)], and {U01 HG06379 and U01 HG06379 Supplement [The Electronic Medical Record and Genomics (eMERGE) Network]}.

Conflict of interest: J.L.B. III, L.W., R.M.W., and the Mayo Clinic have stock ownership and have licensed intellectual property to OneOme LLC.

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