CDC Working Group Doesn't Back Genetic Test for Depression Treatment Efficacy
The independent Evaluation of Genomic Applications in Practice and Prevention Working Group has issued its first recommendation, saying it found insufficient evidence to support a recommendation for or against use of CYP450 testing in adults who are beginning treatment with selective serotonin reuptake inhibitors (SSRIs), which are the first-line choice for drug therapy in the United States. The statement says the CYP450 family of enzymes is a major subset of all drug-metabolizing enzymes, and testing for it could guide treatment for the large number of patients suffering depression, with individualized treatment possibly reducing lost work and school days and improving patients' quality of life. Other factors, including diet and medications, also affect SSRI metabolism, it notes.
A Dec. 19 news CDC release quoted Muin J. Khoury, M.D., Ph.D., director of the National Office of Public Health Genomics at the Centers for Disease Control and Prevention (this office created the working group in 2005), and said the recommendation statement has been published in the December issue of Genetics in Medicine and is available at www.egappreviews.org. "With the expected increase in the number of genetic tests in practice, this recommendation statement from the working group marks the beginning of a sustained public health approach to independent assessment of genomic applications in clinical and public health practice. The multidisciplinary EGAPP Working Group prioritizes and selects tests for review, considers the available evidence, provides recommendations on appropriate use of genetic tests in specific clinical scenarios, and highlights critical knowledge gaps," Khoury said.
The working group's statement says its member found no evidence linking testing for CYP450 to clinical outcomes in adults treated with SSRIs. Some studies of a single dose of SSRI in healthy patients reported an association, but this was not supported by studies of patients receiving ongoing SSRI treatment, according to the seven-page statement. "In the absence of evidence supporting clinical utility, it is not known if potential benefits from CYP450 testing will outweigh potential harms," it states. "Potential harms may include increased cost without impact on clinical decision making or improvement in patient outcomes, less effective treatment with SSRI drugs, or inappropriate use of genotype information in the management of other drugs metabolized by CYP450 enzymes."