OpalGenix’s Evidence-Based and Patent Technology

OpalGenix’s GPS-Opioid™ technology was developed based on Dr. Sadhasivam’s extensive NIH-funded clinical research on opioid pharmacogenetics and personalized surgical pain management. OpalGenix’s technology has received over ten US- and European Patent Treaty Office-approved patent claims.

Evidence-Based Technology

Selected Peer-Reviewed Publications Supportive of GPS-Opioid™

    1. Ramsey LB, Prows CA, Chidambaran V, Senthilkumar Sadhasivam, Quinn CT, Teusink-Cross A, Girdwood ST, Dawson DB, Vinks AA, Glauser TA. Implementation of CYP2D6-guided opioid therapy at Cincinnati Children’s Hospital Medical Center. Am J Health Syst Pharm. 2023 Jan 28:zxad025. doi: 10.1093/ajhp/zxad025. Epub ahead of print. [PMID: 36715063] (Full Article – Free Access)

    2. Merchant S, Prows CA, Yang F, Ding L, MacDonald J, Zhang X, Senthilkumar Sadhasivam, Garcia V, Sturm P, Chidambaran V. Association of CYP2D6 genotype predicted phenotypes with oxycodone requirements and side effects in children undergoing surgery. Ann Transl Med. 2022 Dec;10(23):1262. doi: 10.21037/atm-2022-58. [PMID: 36618804] [PMCID: PMC9816853] (Full Article – Free Access)

    3. Packiasabapathy S, Aruldhas BW, Zhang P, Overholser BR, Quinney SK, Senthilkumar Sadhasivam. Novel associations between CYP2B6 polymorphisms, perioperative methadone metabolism and clinical outcomes in children. Pharmacogenomics. 2021 Jul;22(10):591-602. doi: 10.2217/pgs-2021-0039. Epub 2021 Jun 8. [PMID: 34100292] [PMCID: PMC8238023] (Full Article – Free Access)

    4. Umukoro NN, Aruldhas BW, Rossos R, Pawale D, Renschler JS, Senthilkumar Sadhasivam. Pharmacogenomics of oxycodone: a narrative literature review. Pharmacogenomics. 2021 Apr;22(5):275-290. doi: 10.2217/pgs-2020-0143. Epub 2021 Mar 17. [PMID: 33728947] [PMCID: PMC8050982] (Full Article – Free Access)

    5. Senthilkumar Sadhasivam, Chidambaran V, Esslinger H, Zhang K, Zhang X, Martin LJ, McAuliffe JM. Opioid induced Respiratory Depression: ABCB1 transporter Pharmacogenetics. The Pharmacogenomics Journal 2015; 15 (2): 119-26. [PMID 25311385] (Full Article – Paid Access)

    6. Senthilkumar Sadhasivam, Zhang X, Chidambaran V, Mavi J, Pilipenko V, Mersha TB, Meller J, Kaufman KM, Martin LJ, McAuliffe JM. Novel Associations between FAAH Genetic Variants Postoperative Central Opioid related Adverse Effects. The Pharmacogenomics Journal 2015; 15 (5): 436-42; doi:10.1038/tpj.2014.79 [PMID: 25558980] [PMCID: PMC4492912] (Full Article – Paid Access)

    7. Biesiada J, Chidambaran V, Wagner M, Meller J, Senthilkumar Sadhasivam. Genetic Risk Signatures of Opioid-induced Postoperative Respiratory Depression following Pediatric Tonsillectomy. Pharmacogenomics 2014; 15 (14): 1749-62. [PMID: 25493568] [PMCID: PMC4287371] (Full Article – Free Access)

    8. Senthilkumar Sadhasivam, Chidambaran V, Olbrecht VA, Costandi A, Esslinger H, Prows C, Zhang X, Martin LJ. Opioid-related adverse effects in children undergoing surgery: Unequal burden on younger girls with higher doses of opioid. Pain Medicine 2015; 16 (5): 985-97. [PMID: 25521773] (Full Article – Free Access)

    9. Senthilkumar Sadhasivam, Olbrecht VA, Chidambaran V, Esslinger H, Zhang K, Zhang X, Martin LJ. Genetics of Pain Perception, COMT and Postoperative Pain Management in Children. Pharmacogenomics 2014; 15 (3): 277-84. [PMID 24533707] [PMCID: PMC4151110] (Full Article – Free Access)

    10. Chidambaran V, Venkatasubramanian R, Zhang X, Martin LJ, Niu J, Mizuno T, Fukuda T, Meller J, Vinks AA, Senthilkumar Sadhasivam. ABCC3 Genetic Variants are Associated with Postoperative Morphine-induced Respiratory Depression and Morphine Pharmacokinetic in Children. The Pharmacogenomics Journal. 2016 (26 January 2016) | doi:10.1038/tpj.2015.98 [PMID: 26810133] [PMCID: PMC4959996] (Full Article – Free Access)

    11. Chidambaran V, Mavi J, Esslinger H, Pilipenko V, Martin LJ, Zhang K, Senthilkumar Sadhasivam. OPRM1 A118G variant Predicts risk of Morphine induced Respiratory Depression in Adolescents with Idiopathic Scoliosis following Spine Fusion, The Pharmacogenomics Journal 2015; 15 (3): 255-62. [PMID: 25266679] (Full Article – Free Access)

    12. Venkatasubramanian R, Fukuda T, Niu J, Mizuno T, Chidambaran V, Vinks AA, Senthilkumar Sadhasivam. ABCC3 and OCT1 genotypes influence Pharmacokinetics of Morphine in Children, Pharmacogenomics 2014; 15 (10): 1297-1309. [PMID 25155932] [PMCID: PMC4190075] (Full Article – Free Access)

    13. Prows CA, Huth MM, Zhang X, Zhang K, Saldaña SN, Daraiseh N, Goodman H, Freeman E, Greinwald J, Martin LJ, Senthilkumar Sadhasivam. Codeine related adverse reactions in children following tonsillectomy: A prospective study. Laryngoscope 2014; 124(5): 1242-50. [PMID 24122716] DOI: 10.1002/lary.24455 (Full Article – Paid Access)

    14. Hahn D, Fukuda T, Euteneuer J, Mizuno T, Vinks AA, Senthilkumar Sadhasivam, Emoto C. Influence of MRP3 genetics and hepatic expression ontogeny for morphine disposition in neonatal and pediatric patients. The Journal of Clinical Pharmacology 2020; August; 60(8): 992-998. doi: 10.1002/jcph.1592. [PMID: 32090339] (Full Article – Paid Access)

    15. Chidambaran V, Zhang X, Martin L, Ding L, Weirauch WT, Spruance K, Senthilkumar Sadhasivam, Ji H. DNA methylation at the Mu Opioid Receptor gene (OPRM1) promoter predicts preoperative, acute and chronic post-surgical pain after spine fusion. Pharmacogenomics and Personalized Medicine 2017; May 9; 10:157-168. doi: 10.2147/PGPM.S132691. [PMID: 28533693] (Full Article – Free Access)

    16. Balyan R, Zhang X, Mizuno T, Chidambaran V, Fukuda T, Vinks AA, Senthilkumar Sadhasivam. OCT1 genetic variants are associated with postoperative adverse opioid outcomes in children. Pharmacogenomics 2017 May 8(7):621-629. doi: 10.2217/pgs-2017-0002. [PMID: 28470102] (Full Article – Free Access)

    17. Balyan R, Mecoli M, Venkatasubramanian R, Chidambaran V, Kamos N, Clay S, Moore D, Prows C, Glover CD, Szmuk P, Vinks AA, Senthilkumar Sadhasivam. CYP2D6 pharmacogenetic and oxycodone pharmacokinetic association study in pediatric surgical patients. Pharmacogenomics 2017 Mar 18(4):337-348. doi: 10.2217/pgs-2016-0183. [PMID: 28244808] (Full Article – Free Access)

    18. Chidambaran V, Ding L, Moore DL, Spruance K, Cudilo E, Hossain M, Sturm P, Kashikar-Zuck S, Senthilkumar Sadhasivam. Predicting the Pain Continuum after Adolescent Idiopathic Scoliosis Surgery – A Prospective Cohort Study. European Journal of Pain 2017 Aug 21(7):1252-1265. doi: 10.1002/ejp.1025. [PMID: 28346762] (Full Article – Free Access)

    19. Chidambaran V, Pilipenko V, Spruance K, Venkatasubramanian R, Niu J, Mizuno T, Fukuda T, Martin LJ, Zhang K, Kaufman K, Vinks AA, Senthilkumar Sadhasivam. Fatty Acid Amide Hydrolase – Morphine interactions influences ventilatory response to hypercarbia and postoperative opioid outcomes in children. Pharmacogenomics 2017; Jan;18(2):143-156. doi: 10.2217/pgs-2016-0147. [PMID: 27977335] (Full Article – Free Access)

    20. Rasmussen-Torvik LJ, Sarah Stallings, Adam Gordon, Berta Almoguera, Melissa Basford, Suzette Bielinski, Ariel Brautbar, Murray Brilliant, David Carrell, John Connolly, David Crosslin, Kimberly Doheny, Carlos Gallego, Omri Gottesman, Daniel Kim, Kathleen Leppig, Rongling Li, Simon Lin, Shannon Manzi, Ana Mejia, Jennifer Pacheco, Vivian Pan, Jyotishman Pathak, Cassandra Perry, Josh Peterson, Cynthia Prows, James Ralston, Luke Rasmussen, Marylyn Ritchie, Senthilkumar Sadhasivam, Stuart Scott, Maureen Smith, Aida Vega, Alexander Vinks, Simona Volpi, Wendy Wolf, Erwin Bottinger, Rex Chisholm, Christopher Chute, Jonathan Haines, John Harley, Brendan Keating, Ingrid Holm, Iftikhar Kullo, Gail Jarvik, Eric Larson, Teri Manolio, Catherine McCarthy, Deborah Nickerson, Steve Scherer, Marc Williams, Dan Roden, and Joshua Denny. Design and Anticipated Outcomes of the eMERGE-PGx Project: A Multi-Center Pilot for Pre-Emptive Pharmacogenomics in Electronic Health Record systems, Clinical Pharmacology and Therapeutics 2014; 96(4): 482-9. [PMID: 24960519] [PMCID: PMC4169732]. (Full Article – Free Access)

    21. Crews KR, Gaedigk A, Dunnenberger HM, Klein TE, Caudle KE, Haidar C, Shen DD, Callaghan JT, Senthilkumar Sadhasivam, Prows C, Kharasch ED, Skaar TC. Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for cytochrome P450 2D6 (CYP2D6) genotype and codeine therapy: 2014 Update, Clinical Pharmacology and Therapeutics 2014; 95(4):376-82. [PMID 24458010] [PMCID: PMC3975212] (Full Article – Free Access)

    22. Subramanyam R, Chidambaran V, Ding L, Myer III, CM, Senthilkumar Sadhasivam. Anesthesia and Opioids- Related Malpractice Claims with Tonsillectomy in USA: LexisNexis claims database 1984-2012. Pediatric Anesthesia 2014, 24(4): 412-20. [PMID: 24417679] (Full Article – Paid Access)

    23. Tsuyoshi Fukuda, Tomoyuki Mizuno, Vidya Chidambaran, Vanessa A. Olbrecht, Raja Venkatasubramanian, Hope R. Esslinger, Alexander A. Vinks, Senthilkumar Sadhasivam. OCT1 genetic variants influence the pharmacokinetics of morphine in children. Pharmacogenomics 2013; July 14(10): 1141-51. [PMID 23859569] [PMCID: PMC4116670] (Full Article – Free Access)

    24. Wang C, Senthilkumar Sadhasivam, Krekels EHJ, Dahan A, Tibboel D, Danhof M, Vinks AA, Knibbe CAJ. Scaling morphine clearance across the human life-span using a bodyweight-dependent allometric exponent model. Clinical Drug Investigation 2013; 33 (7): 523-34. [PMID 23754691] (Full Article – Paid Access)

    25. Senthilkumar Sadhasivam, Chidambaran V, Ngamprasertwong P, Esslinger H, Prows C, Zhang X, Martin LJ, McAuliffe J. Race and Unequal Burden of Perioperative Pain and Opioid Related Adverse Effects in African-American and Caucasian Children, Pediatrics 2012; 129 (5): 832-838. [PMID: 22529273] [PMCID: PMC3340593]. (Full Article – Free Access)

    26. Senthilkumar Sadhasivam, Krekels E, Chidambaran V, Esslinger HR, Ngamprasertwong P, Zhang K, Fukuda T, Vinks AA. Morphine Clearance in Children: Does Race or Genetics Matter? Journal of Opioid Management 2012; 8(4): 217-226. [PMID: 22941849] (Full Article – Paid Access)

    27. Senthilkumar Sadhasivam, Myer III CM. Preventing Opioid Related Deaths in Children Undergoing Surgery. Pain Medicine 2012; 13 (7): 982-3. [PMID: 22694279] (Full Article – Paid Access)

    28. Lingren T, Senthilkumar Sadhasivam, Zhang X, Marsolo K. Electronic Medical Records as a replacement for prospective research data collection in postoperative pain and opioid response studies. International Journal of Medical Informatics 2018; March; 111:45-50. doi: 10.1016/j.ijmedinf.2017.12.014. [PMID: 29425633] (Full Article – Free Access)

    29. Chidambaran V, Subramanyam R, Ding L, Senthilkumar Sadhasivam, Geisler K, Stubbeman B, Sturm P, Jain V, Eckman MH. Cost-effectiveness of intravenous acetaminophen and ketorolac in adolescents undergoing idiopathic scoliosis surgery. Paediatric Anaesthesia 2018 Mar;28(3):237-248. doi: 10.1111/pan.13329. [PMID: 29377376] (Full Article – Free Access)

    30. Olbrecht V, Ding L, Spruance K, Hossain M, Chidambaran V, Senthilkumar Sadhasivam, Chidambaran V. Intravenous Acetaminophen Reduces Length of Stay Via Mediation of Postoperative Opioid Consumption following Posterior Spinal Fusion in a Pediatric Cohort. Clinical Journal of Pain 2018; 34(7): 593-599. doi: 10.1097/AJP.0000000000000576. [PMID: 29200016] (Full Article – Free Access)

    31. Jian Ye, Karen Myung, Packiasabapathy S, Jeffrey S. Yu, Joseph Jacobson, Stephanie Whittaker, Peter Castelluccio, Senthilkumar Sadhasivam. Methadone-Based Multimodal Analgesia Provides the Best-In-Class Acute Surgical Pain Control and Functional Outcomes with Lower Opioid Use Following Major Posterior Fusion Surgery in Adolescents With Idiopathic Scoliosis. Pediatric Quality & Safety 2020; July 27; 5(4): e336; DOI:10.1097/pq9.0000000000000336. [PMID: 32766507] (Full Article – Free Access)

    32. Packiasabapathy S, Winston B, Horn N, Overholser B, Renschler J, Senthilkumar Sadhasivam. Pharmacogenomics of Methadone: A Narrative Review of Literature. Pharmacogenomics 2020; Aug;21(12):871-887. doi: 10.2217/pgs-2020-0040. [PMID: 32705966] (Full Article – Free Access)

    33. Packiasabapathy S, Rangasamy V, Horn N, Hendrickson M, Renschler J, Senthilkumar Sadhasivam. Personalized pediatric anesthesia and pain management: Problem-based review. Pharmacogenomics 2020 Jan; 21(1): 55-73. doi: 10.2217/pgs-2019-0108. [PMID: 31849281] (Full Article – Free Access)

    34. Packiasabapathy S, Senthilkumar Sadhasivam. Gender, genetics, and analgesia: understanding the differences in response to pain relief. Journal of Pain Research 2018; 11: 2729-2739. doi: 2147/JPR.S94650. [PMID: 30519077] (Full Article – Free Access)

    35. Packiasabapathy S, Horn N, Senthilkumar Sadhasivam. Genetics of Perioperative Pain Management. Current Opinion in Anesthesiology, December 2018; 31(6):749-755. doi: 1097/ACO.0000000000000660. [PMID: 30239351] (Full Article – Free Access)

    36. Chidambaran V, Senthilkumar Sadhasivam, Mahmoud M. Codeine and Opioid Metabolism – Implications and alternatives for pediatric pain management. Current Opinion in Anesthesiology 2017 Mar 18. doi: 10.1097/ACO.0000000000000455. [PMID: 28323671] (Full Article – Free Access)

    37. Senthilkumar Sadhasivam, Vidya Chidambaran. Pharmacogenetics and Personalizing Perioperative Analgesia. Pharmacogenomics, 2012; 13(15): 1719-40. [PMID: 23171337] (Full Article – Paid Access)

    38. Vidya Chidambaran, Pornswan Ngamprasertwong, Alexander Vinks, Senthilkumar Sadhasivam. Pharmacogenetics and Anesthetic Drugs. Current Clinical Pharmacology 2012; 7: 78-101. [PMID: 22432844] (Full Article – Paid Access)

    39. Cohen M, Senthilkumar Sadhasivam, Vinks AA. Pharmacogenetics in Perioperative Medicine, Current Opinion in Anesthesiology 2012 August; 25 (4): 419-27. [PMID: 22673786] (Full Article – Paid Access)

    40. Senthilkumar Sadhasivam, Winston B, Overholser B, Packiasabapathy S, Renschler J, Quinney S. A Novel Perioperative Multi-dose Methadone-based Multimodal Analgesic Strategy in Children achieves Safe and Low Analgesic Blood Methadone Levels enabling Opioid-sparing Sustained Analgesia with Minimal Adverse. Anesthesia and Analgesia Anesth Analg. 2021 Aug 1;133(2):327-337. doi: 10.1213/ANE.0000000000005366. [PMID: 33481403] [PMCID: PMC8282724] (Full Article – Free Access)

    41. Emoto C, Fukuda T, Johnson T, Neuhoff S, Senthilkumar Sadhasivam, Vinks AA. Characterization of contributing factors to variability in morphine clearance through PBPK modeling implemented with OCT1 transporter. Clinical Pharmacology and Therapeutics: Pharmacometrics & Systems Pharmacology 2017; 6(2): 110-119. doi: 10.1002/psp4.12144. [PMID: 27935268] (Full Article – Free Access)

    42. Bell GC, Caudle KE, Whirl-Carrillo M, Gordon RJ, Hikino K, Prows CA, Gaedigk A, Agundez JAG, Senthilkumar Sadhasivam, Klein TE, Schwab M. Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for CYP2D6 genotype and Use of Ondansetron and Tropisetron. Clinical Pharmacology and Therapeutics 2017 Aug;102(2):213-218. doi: 10.1002/cpt.598.[PMID: 28002639] (Full Article – Free Access)

    43. Chidambaran V, Olbrecht VA, Hossain M, Senthilkumar Sadhasivam, Rose J, Meyer MJ. Risk Predictors of Opioid Induced Critical Respiratory Events in Children: Naloxone Use as a Quality Measure of Opioid Safety. Pain Medicine 2014; 15 (12): 2139-49. [PMID 25319840] (Full Article – Free Access)


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