Study on Preliminary Safety and Efficacy of the ARC Therapy Using the ARC-IM Lumbar System to Support Mobility in People With Chronic Spinal Cord Injury (BoxSwitch)

The purpose of this pre-market clinical study is to assess the preliminary safety and efficacy of the ARC Therapy using the ARC-IM Lumbar System at supporting mobility in participants with chronic spinal cord injury. Only participants that have undergone the STIMO study (NCT02936453) will be proposed to exchange their currently implanted system with components of the newly developed ARC-IM Lumbar system. The goal is to improve more effective lower-limb motor activities, while also simplifying the personal at-home use of the system. In addition, this study aims to evaluate the potential effect of ARC Therapy on muscle tone, bladder, bowel and sexual functions, and quality of life of the participants.

Preliminary safety and efficacy will be assessed in both the short term and throughout the duration of the study (from the surgery to 36 months after the implantation of the ARC-IM Lumbar system).

Studies have shown that using Electrical Epidural Stimulation (EES) could improve considerably the functional movements after paralyzing SCI. In the STIMO study (NCT02936453), the investigational system was mainly composed of medical devices developed for other indications and used off-label, allowing only a limited tuning of EES protocols. To overcome this limitation, we propose to conduct a study in which a new platform will be investigated. This new therapy, named ARC Therapy, features the ARC-IM implantable pulse generator with an optimized communication system and the ARC-IM implantable leads supporting stimulation protocols specifically developed for effective activation of motor neurons.

The study will take place at the CHUV (Lausanne, Switzerland). A maximum of 8 participants will be enrolled in the study and implanted with an ARC-IM IPG. Only participants that have undergone the STIMO protocol (NCT02936453) can enrol in the current BoxSwitch study. Replacement of their currently implanted IPG and lead will be assessed on a case-by-case manner considering current status of their implanted devices, technical and surgical compatibility with the newly proposed ARC-IM Lumbar system components.

The study intervention consists of several phases preceded by pre-screening:

Screening and enrollment, baseline and pre-implantation assessments, surgery, optimization phase, short-term assessments, independent use phase and follow-up assessments at months 12, 24 and 36. Measures will be performed before surgical intervention and at regular intervals during the study.

The total duration of the study will be approximately 48 months (up to 36 months/participant).

Eligibility Criteria:
Inclusion Criteria:

1. Having completed the main phase of the STIMO study (NCT02936453) and having improved on at least one of the primary or secondary endpoints (WISCI II Score, 10-Meter Walk test, Weight Bearing Capacity, SCIM III Score or 6-Minute Walk test).
2. Age 18-65
3. SCI graded as American Spinal Injury Association Impairment Scale (AIS) A, B, C \& D
4. SCI ≥ 12months
5. SCI lesion level T10 and above with preservation of conus function
6. SCI due to trauma
7. Stable medical, physical and psychological condition as considered by the investigators
8. Able to understand and interact with the study team in French or English
9. Agrees to comply in good faith with all conditions of the study and to attend all scheduled appointments
10. Must provide and sign the Informed Consent prior to any study-related procedures

Exclusion Criteria:

1. Diseases and conditions that would increase the morbidity and mortality of spinal cord injury surgery
2. History of myocardial infarction or cerebrovascular event within the past 6 months
3. Limitation of walking function based on accompanying (CNS) disorders (systemic malignant disorders, cardiovascular disorders restricting physical training, peripheral nerve disorders)
4. Any active implanted cardiac device such as pacemaker or defibrillator
5. Any indication that would require diathermy
6. Any indication that would require MRI
7. Any anatomical limitations in the implantation area as judged by the investigators
8. Other conditions that would make the subject unable to participate in testing in the judgement of the investigators
9. Clinically significant mental illness in the judgement of the investigators
10. Presence of indwelling baclofen or insulin pump
11. Other clinically significant concomitant disease states (e.g., renal failure, hepatic dysfunction, cardiovascular disease, etc.)
12. Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, or dementia of the participant
13. Enrolment of the investigator, his/her family members, employees, and other dependent persons