Electroencephalogram (EEG) measures electrical discharges in the brain through various measurements, such as phases, frequency, and amplitude. While EEG has been used prominently to diagnose epilepsy, it has also been helpful in the discovery and diagnosis of many other neurological disorders, such as brain tumors, sleep disorders, and behavioral disorders. Measuring electrical activity within the brain can also be beneficial in determining safety, efficacy, and dosage in clinical trials.
Uses of EEG in Clinical Trials
- Drug Safety
EEG can be helpful in determining the safety of drugs as many medications can have visible effects on the EEG. The effects of the drugs may cause increased amount of beta activity that is typically seen with barbiturates and benzodiazepines. However, some drugs can also have more detrimental changes including tremors, myoclonus, altered mental status, cognitive function changes, and seizures. All of which would be detected by performing an EEG.
- Identify Side-Effects
Video EEG is extremely helpful when diagnosing seizures and other neurological disorders. Being able to visibly see the physical movements of the trial patient and compare them with the electrical activity of their brain is critical to accurately diagnosing side-effects of the drug. Video can also give insights into how severe the side-effect may be.
- Determination of Dosage
EEG can be used in detecting any dose-related changes after exposure to the drug. This would help identify an adequate dosage that maximizes efficacy while minimizing side effects.3 As previously mentioned, beta activity may arise most commonly with the introduction of barbiturates and benzodiazepines. Additionally, a sudden withdrawal from barbiturates can cause a burst of spikes or polyspikes to be seen on the EEG.1 Being able to modify and regulate the amount of medication being administered to the patient based off of the EEG data may decrease the probability of drug intoxication and harm to the patient. 1
- Pinpoint Outliers
Obtaining a baseline EEG in the cohorts of a clinical trial is helpful in identifying interictal epileptiform discharges that would suggest that the patient may be predisposed to have a seizure disorder. For example, if the participant had taken the trialed drug and had a seizure, that medication would then have to list seizure as a potential side effect. If the baseline EEG were obtained prior to the trial and showed evidence that the patient was predisposed, the specific symptom would be noted within their clinical history and in turn would not be documented as a side effect from the drug. Ultimately, this would more accurately suggest the side effects of the medication and reduce patient concerns.
- Non-invasive, Safe, & Cost Effective
Due to EEG testing being non-invasive and posing minimal risk to the trial’s participants, EEG is an ideal tool for repeated measurements over a long period of time in clinical trials. In comparison to other neuroimaging techniques such as MRI or PET scans, EEG equipment is typically less costly and easier to operate. Collecting and analyzing data from EEG can be completed relatively quickly, which would reduce overall cost and duration of clinical trials. 3
Add EEG to Your Clinical Trial
Stratus is the largest provider of EEG services in the United States, serving over 525 hospitals and 1,200 private neurology practices. Stratus also offers turnkey video EEG testing for pharmaceutical and medical device clinical trials. We have technicians available across the country to allow for multisite trial locations or decentralized clinical trials from the patient’s home. Clinical trial services include full-service video EEG with optional cardiac testing, web-based EEG data access, elective interpretation services, and trial design coordination and more. Contact Stratus today for more information.
About the Author
Morgan Palliser, R. EEG T., is a clinical product specialist and Registered EEG Technologist at Stratus. Morgan graduated from an accredited Neurodiagnostic program, and completed a two-year internship with the University of Missouri Hospital where she continued to work full-time in the Neurodiagnostic Lab until May of 2020. She has experience in inpatient/outpatient EEG for all ages, long-term EEG monitoring, polysomnography, and nerve conduction studies. Outside of work, Morgan is the president of MO-SET (Missouri Society of Electroneurodiagnostic Technologists), where she oversees the board in decision making for the annual educational conference that allows CEUs for her fellow neurodiagnostic colleagues.
References
- Blume WT. Drug effects on EEG. Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society [Internet]. 2006 Aug 1;23(4):306–11. Available from: https://www.ncbi.nlm.nih.gov/pubmed/16885705
- MD Anderson Cancer Center. Phases of Clinical Trials [Internet]. MD Anderson Cancer Center. 2024. Available from: https://www.mdanderson.org/patients-family/diagnosis-treatment/clinical-trials/phases-of-clinical-trials.html
- Jeremy Slater, MD, Chief Medical Officer at Stratus
