Pharmacogenetic Decision Support IT System for Psychiatric Hospitalization: RCT

Over 1.4 million hospitalizations for mental health conditions occur annually in the United States (3.4% of all hospitalizations), and more than half are for major depressive disorder (MDD). Remarkably, of the 30 antidepressant and antipsychotic medications available to treat MDD, nearly 50% are primarily metabolized by the liver enzyme encoded by the CYP2D6 gene. The CYP2D6 gene is notable for common sequence and structural polymorphisms which markedly affect the enzyme's capacity, causing a decrease or increase in drug metabolism in 60% of patients, and creating challenges for therapeutic management. The metabolic alterations caused by CYP2D6 gene polymorphisms may require longer hospitalizations due to "trial-and-error" prescribing, which delays improvement in health status and consumes resources. Reliable genotype testing is now available to detect an array of 21 gene alterations. Prescribing psychotropics using knowledge of the patient's CYP2D6 gene status is potentially cost effective.

For this research, the Genetics Research Center performs the CYP2D6 genotyping, and the Institute of Living's Clinical Evaluation and Monitoring System (CEMS) transmits explicit alerts regarding prescription or proscription of specific psychotropics.

The RCT will compare outcomes in patients whose treatment is guided by CYP2D6 functional status and pharmacogenetic alerts versus standard-of-care treatment to test the hypothesis that the provision of clinically actionable prescription or proscription information can decrease hospitalization length of stay and reduce subsequent readmission.

Using funds from AHRQ R01 HS022304-01, the RCT will enroll patients admitted to IOL over the next 5 years with a diagnosis of MDD and who are receiving psychotropic therapy at the time of admission or who will receive psychotropic therapy during hospitalization. Patients will be assigned to standard-of-care pharmacotherapy (Group S), where CYP2D6 genotype is determined but not transmitted to the clinician and psychotropic therapy follows the institutional norm. Patients will be assigned to genetically-guided pharmacotherapy (Group G) where pharmacogenetic alerts based on CYP2D6 genotype are furnished via CEMS to the clinician within 48 hours of admission. Genotyping encompasses 19 common polymorphisms in CYP2D6 and their quantification into a drug metabolism reserve index to establish levels of sub-normal function (poor metabolizer) or supra-normal function (rapid metabolizer). For the estimated 40% of patients in Group G who are poor or rapid metabolizers, CEMS will proscribe medications which are major CYP2D6 substrates.

The PI is Dr. Gualberto Ruaño, Director of GRC, and the lead clinician and Co-I is Dr. John Goethe, retired Director of IOL's Burlingame Research Center. Drs. Ruaño and Goethe have previously collaborated for 15 years on the pharmacogenetics of CYP450 and psychotropics. Dr. Theodore Holford of Yale University serves as statistical consultant.