A Pharmacogenetically Guided Acenocoumarol Dosing Algorithm for Chilean Patients: A Discovery Cohort Study

Pharmacogenomics in Lebanon: current status, challenges and opportunities

Pharmacogenomics (PGx) research and applications are of utmost relevance in Lebanon considering its population genetic diversity. Moreover, as a country with regional leadership in medicine and higher education, Lebanon holds a strong potential in contributing to PGx research and clinical implementation. In this manuscript, we first review and evaluate the available PGx research conducted in Lebanon, then describe the current status of PGx practice in Lebanon while reflecting on the local and regional challenges, and highlighting areas for action, and opportunities to move forward. We specifically expand on the status of PGx at the American University of Beirut Faculty of Medicine and Medical Center as a case study and guide for the further development of local and regional comprehensive PGx research, teaching, and clinical implementation programs. We also delve into the status of PGx knowledge and education, and prospects for further advancement such as with online courses and certificates.

CYP2C9*3 Increases the Ibuprofen Response of Hemodynamically Significant Patent Ductus Arteriosus in the Infants with Gestational Age of More Than 30 Weeks

Hemodynamically significant patent ductus arteriosus (hsPDA) is a severe condition in newborns. Ibuprofen is an effective treatment to reduce the severe complications and the need for surgical treatment. Several single-nucleotide polymorphisms (SNPs) were related to the ibuprofen metabolism, treatment effects, and the onset of side effects. The effects of SNPs on hsPDA response after ibuprofen treatment are unknown. Therefore, in this study, we recruited hsPDA patients with standard ibuprofen treatment. Those patients had participated in China Neonatal Genomes Project (CNGP, ClinicalTrials.gov Identifier: NCT03931707) with next-generation sequencing data. We reanalyzed the sequencing data and compared the allele frequencies of known ibuprofen-related SNPs between ibuprofen Responder and Non-responder groups. In total, 185 hsPDA patients were recruited with gestational age (GA) ranging from 24 to 40 weeks. No significant differences were detected in the basic information, period of ibuprofen treatment, rate of conservative treatment, complications, and side effects between ibuprofen Responder group and Non-responder group. Totally, 17 hsPDA carried CYP2C9*3 and one with CYP2C9*2 were detected. In the GA group of more than 30 GA weeks (GA > 30 wks group), we found higher allele frequency of CYP2C9*3 in Responder group than in Non-responder group (16% vs. 0, p = 0.0391). In the GA group of less than 30 GA weeks (GA ≤ 30 wks group), the sum allele frequency of CYP2C9*3 and CYP2C9*2 had no stastical difference between two groups (Responder group vs. Non-responder group, 13% vs. 11%, p = 0.768). Therefore, we came to conclude that genetic tests of CYP2C9*3 site may benefit the prediction of ibuprofen treatment outcome for hsPDA patients with gestational age of more than 30 weeks.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s43657-021-00028-9.

Retrospective pharmacogenetic analysis of a pediatric patient under anticoagulant treatment: Clinical case

We present the clinical case of a 10-year-old patient diagnosed with dilated cardiomyopathy who registered INR values above 10 upon receiving standard doses of acenocoumarol, as well as other values reported as uncoagulable, forcing the discontinuation and restart of treatment more than once. Expected and stable INR levels were achieved after more than 30 days of treatment, surprisingly with half the recommended dose for a patient of her age and weight. We decided to conduct a retrospective pharmacogenomic analysis including nucleotide genetic polymorphisms (SNPs) with different degrees of association with the dose/response to antivitamin K (AVK) drugs: rs2108622 (gene CYP4F2), rs9923231, rs7294 (gene VKORC1), rs1799853, and rs1057910 (CYP2C9 gene) using TaqMan® RT-PCR. The patient was homozygous for rs9923231 (VKORC1) and heterozygous for rs2108622 (CYP4F2),a genetic profile strongly associated with a requirement of lower AVK doses as shown by national and international evidence. In conclusion, the pharmacogenetic analysis confirmed that this patient’s genetic conditions, involving low expression of the VKA therapeutic target, required a lower dose than that established in clinical protocols as recommended by the Food and Drug Administration (FDA) and the PharmGKB® for coumarin drugs. A previous genotypic analysis of the patient would have allowed reaching the therapeutic range sooner, thus avoiding potential bleeding risks. This shows the importance of pharmacogenetic analyses for highly variable treatments with a narrow therapeutic range.

CYP4F2 and VKORC1 Polymorphisms Amplify the Risk of Carotid Plaque Formation

Introduction: Atherosclerosis represents the process by which fibrous plaques are formed in the arterial wall, increasing its rigidity with a subsequent decrease in blood flow which can lead to several cardiovascular events. Seeing as vitamin K antagonists are involved in the pathogenesis of atherosclerosis, we decided to investigate whether polymorphisms in genes that influence vitamin K metabolism might have an impact in modulating the risk of plaque formation. Patients and Methods: In the current study we included adult patients admitted in the Clinical Municipal Hospital of Cluj-Napoca without any carotid or femoral plaques clinically visible at the initial investigation, and a five year follow-up was subsequently performed. We recorded the following patient characteristics: age at inclusion, gender, area of living, smoking, presence of carotid and/or femoral plaques at five years, ischemic heart disease, arterial hypertension, atrial fibrillation, heart failure, diabetes mellitus, obesity, dyslipidemia, drug (oral anticoagulants, antihypertensives, hypolipidemic, anti-diabetic) use and status for the following gene polymorphisms: VKORC1 1639 G>A, CYP4F2 1347 G>T and GGCX 12970 C>G. Results: We observed that the major predictor of both carotid and femoral plaque formation is represented by ischemic cardiac disease. VKORC1 and CYP4F2 polymorphisms did not predict plaque formation, except for VKORC1 homozygous mutants. Nonetheless, both VKORC1 and CYP4F2 interacted with ischemic cardiac disease, increasing the risk of developing a carotid plaque, while only CYP4F2, but not VKORC1, interacted with ischemic cardiac disease to increase the risk of femoral plaque formation. Conclusions: We documented that CYP4F2 and VKORC1 polymorphisms boost the proinflammatory plaque environment (observed indirectly through the presence of ischemic heart disease), increasing the risk of plaque development.