The objective of this study was to determine if the Common Terminology Criteria for Adverse Events (CTCAE) sufficiently defines symptoms experienced by neurological patients in interventional trials.

The Common Toxicology Criteria was established to standardize toxicity reporting in oncology trials and later expanded into the CTCAE to grade the severity of adverse events (AEs). With more than 80,000 Medical Dictionary for Regulatory Activities (MedDRA) terms, CTCAE only contains 585 (0.7%) MedDRA terms. Additionally, the literature suggests that this reporting system lacks sensitivity and unreliably defines neurological symptoms. This study aims to investigate AEs in neurological patients and ascertain if the CTCAE appropriately describes these symptoms.

AE logs for eight active interventional protocols were reviewed. Each AE was recorded with patient information, dates, investigator’s AE term, type of protocol, and severity of CTCAE grade. The medical record was utilized to retrieve AE descriptions. Based on patient charts, each AE was determined to either be sufficiently defined by the CTCAE or deemed to have a more accurate MedDRA term. The frequency of investigators utilizing the “Other” classification was tabulated to determine how often investigators lacked appropriate CTCAE terms to classify symptoms.

In total, 771 recorded AEs were analyzed. The trials included: neurological complications of HIV (two), Parkinson’s Disease (two), multiple sclerosis (one), HTLV-1-associated myelopathy (one), glioblastoma (one), and chronic fatigue syndrome (one). Approximately 60% of the 771 AEs were sufficiently defined by the CTCAE, while approximately 40% were more appropriately defined by a non-CTCAE MedDRA term. Additionally, in 113 (15%) instances, AEs were classified as "Other" because investigators were unable to describe AEs with CTCAE terms. 

Non-CTCAE MedDRA terms more accurately defined AEs in many investigations of neurological diseases. By utilizing more accurate symptom-defining terms, the AE reporting process could be standardized to optimize patient safety in neurological interventional trials.