RESEARCH EVALUATING VAGAL EXCITATION AND ANATOMICAL LINKS
The acute and chronic effects of VNS stimulation on various on the autonomic nervous, cardiovascular, immune, and metabolic systems will be compared from noninvasive and minimally invasive physiological recordings and blood draws at various time points throughout the study. These interventions and assessments will be performed in individuals 18 years of age and older who are implanted with a VNS device, which consists of patients who have been diagnosed with drug resistant epilepsy or major depressive disorder. The REVEAL study is not a treatment study; its primary objective is to scientifically investigate the contributing roles of efferent versus afferent vagus nerve modulation of multiple peripheral organs and their dependence on stimulation parameters, in which participants are those who have been implanted with a VNS device be receive standard of care treatment for their epilepsy or depressive disorder.
⁃ Cohort 1a (p-VNS): Inclusion Criteria for Participants With Major Depressive Disorder That Have a Previously Implanted VNS Device
• Participant must be at least 18 years old.
• Participant must have the capacity to provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization.
• Participant must be enrolled in an active health insurance plan that will cover the costs associated with standard health care services and injuries.
• Participant must have been previously implanted with a VNS device for the clinical indication of Major Depressive Disorder (MDD).
• Participant must be able and willing to complete the evaluations and procedures described in the study protocol.
• Participant's usage of concomitant medications must be stable for two months preceding study enrollment and the participant must be able and willing to maintain stable usage of any concomitant medications from the day of enrollment through the completion of Study Visit 2.
• Participant that is of childbearing potential must be adequately protected from conception or willing to use an acceptable method of birth control over the entire study duration (acceptable birth control includes abstinence, barrier methods, hormonal methods, sterilization and fertility awareness).
⁃ Cohort 1b (n-VNS): Inclusion Criteria for Participants With Major Depressive Disorder That Will Receive a Newly Implanted VNS Device
• Participant must be at least 18 years old.
• Participant must have the capacity to provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization.
• Participant must be enrolled in an active health insurance plan that will cover the costs associated with standard health care services and injuries.
• Participant has a diagnosis of chronic (≥ 2 years) or ≥ 4 recurrent depressive episodes as defined by DSM-5 criteria documented using the MINI criteria and psychiatric medical record review. Participant must have VNS therapy clinically indicated.
• Participant has not had an adequate response to four or more adequate antidepressant treatments from at least two different antidepressant treatment categories in the current depressive episode according to the Antidepressant Treatment History Form (ATHF).
• Participant must have a score on the baseline administration of the Montgomery-Åsberg Depression Rating Scale (MADRS) of ≥ 22.
• Participant must be able and willing to complete the evaluations and procedures described in the study protocol.
• Participant's usage of concomitant medications must be stable for two months preceding study enrollment and the participant must be able and willing to maintain stable usage of any concomitant medications from the day of enrollment through the completion of Study Visit 2.
• Participant that is of childbearing potential must be adequately protected from conception or willing to use an acceptable method of birth control over the entire study duration (acceptable birth control includes abstinence, barrier methods, hormonal methods, sterilization and fertility awareness).
⁃ Cohort 2a (p-VNS): Inclusion Criteria for Participants With Drug Resistant Epilepsy That Have a Previously Implanted VNS Device
• Participant must be at least 18 years old.
• Participant must have the capacity to provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization.
• Participant must be enrolled in an active health insurance plan that will cover the costs associated with standard health care services and injuries.
• Participant must have been previously implanted with a VNS device for the clinical indication of drug resistant epilepsy.
• Participant has not had demonstrable benefit from the implanted VNS device in terms of epilepsy (seizure frequency or seizure severity) or related epilepsy comorbidities (mood, cognition, quality of life), with no definite improvement or suboptimal improvement in seizure control.
• Apart from epilepsy, the participant should be medically and neurologically stable.
• Participant must be able and willing to complete the evaluations and procedures described in the study protocol.
• Participant's usage of concomitant medications must be stable for two months preceding study enrollment and the participant must be able and willing to maintain stable usage of any concomitant medications from the day of enrollment through the completion of Study Visit 2.
• Participant that is of childbearing potential must be adequately protected from conception or willing to use an acceptable method of birth control over the entire study duration (acceptable birth control includes abstinence, barrier methods, hormonal methods, sterilization and fertility awareness).
⁃ Cohort 2b (n-VNS): Inclusion Criteria for Participants With Drug Resistant Epilepsy That Will Receive a Newly Implanted VNS Device
• Participant must be at least 18 years old.
• Participant must have the capacity to provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization.
• Participant must be enrolled in an active health insurance plan that will cover the costs associated with standard health care services and injuries as well as the costs associated with the VNS implantation surgery.
• Participant is diagnosed with drug resistant epilepsy, with continuing seizures despite adequate trials of at least 2 appropriate antiseizure drugs (ASDS) with therapeutic serum concentrations as per the International League Against Epilepsy (ILAE) Commission on Therapeutic Strategies.
• Apart from epilepsy, the participant should be medically and neurologically stable.
• Participant must be able and willing to complete the evaluations and procedures described in the study protocol.
• Participant's usage of concomitant medications must be stable for two months preceding study enrollment and the participant must be able and willing to maintain stable usage of any concomitant medications from the day of enrollment through the completion of Study Visit 2.
• Participant that is of childbearing potential must be adequately protected from conception or willing to use an acceptable method of birth control over the entire study duration (acceptable birth control includes abstinence, barrier methods, hormonal methods, sterilization and fertility awareness).
• Participant has been informed of his or her eligibility for resective surgery as a potential alternative to receiving, as standard of care, the VNS device that is required for participation in this study, if such surgery is a reasonable option.