Aspect Medical Systems, maker of the bispectral index (BIS) monitor thought to be useful for monitoring anesthesia awareness, has been dealt a devastating blow last year by a study published in NEJM under the title Anesthesia Awareness and the Bispectral Index. The 2000 strong patient trial reported by Avidan, et al from Washington University School of Medicine in St. Louis has found the company’s processed electroencephalogram technology is not essential “as part of standard practice.”

Now Aspect Medical Systems is trying its hand in a new market: psychiatry. Finding an appropriate medication, as well as its dose, for a particular patient with bipolar disorder can take a good deal of time and is done without real quantitative tools. The clinical trial being reported by Aspect Medical is supposedly showing that the company’s EEG-based system can be used to track whether a given SSRI (selective serotonin reuptake inhibitor, like Prozac or Paxil) is having positive results on a patient a week after initial doses were administered.

The BRITE trial was conducted in collaboration with leading investigators from nine facilities across the United States and enrolled 375 patients. Patient response was defined by researchers as a 50 percent improvement in depression symptoms as measured by the Hamilton Depression Rating Scale (HAM-D) after seven weeks of treatment, and remission was defined as recovery from depression (HAM-D <7) after seven weeks of treatment. In the BRITE study, ATR at one week predicted response and remission with 74 percent accuracy in subjects treated for seven weeks with escitalopram, which was statistically significant. Modeled study data also indicates that subjects who were ATR predicted non-responders to escitalopram had better outcomes if they were randomized to switch to bupropion, an antidepressant with a different mechanism of action than escitalopram.

Data from a study at Massachusetts General Hospital (MGH) investigating ATR as a predictor of treatment response was also recently published in European Neuropsychopharmacology. The MGH study evaluated ATR in 82 major depression patients receiving selective serotonin reuptake inhibitors (SSRI), and venlafaxine, and showed that use of ATR after the first week of antidepressant treatment may be predictive of treatment efficacy.

Continuing the ATR research effort, BRITE trial investigator Dr. Ian Cook at UCLA received a significant grant from the National Institutes of Mental Health to conduct a multi-year follow-on study of ATR called the PRISE-MD study (Personalized Response Indicators of SSRI Effectiveness in Major Depression). The PRISE-MD study will prospectively evaluate the ability of ATR to predict response to escitalopram as well as the clinical utility of ATR-directed treatment with escitalopram or an alternate treatment with bupropion.