Performance and Long-term Safety of FlowOx2.0™, Multiple Sclerosis, Spasticity and Pain

This study is based on a 4-week double-blind, randomized, controlled, parallel design investigation to investigate the impact of intermittent negative pressure on spasticity and pain in people with multiple sclerosis (pwMS) (NCT05562453). The investigational device (FlowOx2.0™) is composed of a Pressure Chamber and a Control Unit (and disposable parts). All subjects will receive the same pressure chamber but be randomized to either a Control Unit that generates intermittent negative pressure (INP) of - (minus) 40 mmHg or a Control Unit that generates INP of - 10 mmHg. FlowOx2.0™ generating -40 mmHg is the investigational device, and FlowOx2.0™ generating -10 mmHg, is the comparator device. After the initial 4-week double-blind period (NCT05562453), all participants will be offered the -40mmHg control unit to be used during a 6-months optional extension part. The participants who volunteer to continue in the 6-months optional extension part will be included in this study.

FlowOx2.0™ is a commercially available device for home treatment of peripheral arterial disease. It is designed to be used at home by patients and has been shown to cause rapid changes in blood flow velocity in the treated leg. Recently, individuals with multiple sclerosis have reported a positive impact on their self-perceived spasticity and pain levels. The study will recruit patients from Norway, Sweden, and Denmark. All subjects will be instructed to treat the most affected leg for 60 minutes per day, preferentially in the evening. The same leg should be treated throughout the study period. A 4-week double-blind part (NCT05562453) is followed by this open investigation in which all randomized subjects that have completed the main part are offered to continue for an additional 6 months using the active device (INP of - 40 mmHg).

Eligibility Criteria:
Inclusion Criteria:

The subjects must meet all the following criteria to be eligible to participate in the clinical investigation:

1. Diagnosed MS according to revised McDonald criteria.
2. Give written informed consent.
3. Age 18-70 years.
4. Stable MS disease without attack within the last three months.
5. Ability to perform the walk tests:

   1. 2-minute walk test, and
   2. 25-Foot walk.
6. Self-reported spasticity in the most affected leg that would be subject to treatment at baseline with a score of ≥ 4, scored using the numeric rating scale (NRS) during the last 24 hours.
7. Pain and/or discomfort related to the spasticity described in inclusion criteria 6., over the last 7 days using the numeric rating scale (NRS).
8. Stable and unchanged treatment of spasticity and pain the last month, as judged by the Investigator.
9. Stable and unchanged disease-modulating treatment for MS last 6 months, as judged by the Investigator.
10. Can self-manage study equipment.
11. Willingness and ability to comply with study procedures, visit schedules, and requirements.
12. Conducted the 4-week double-blind part of the study (NCT05562453).

Exclusion Criteria:

Subjects meeting any of the following criteria will not be permitted to participate in the clinical investigation:

1. Have spasticity due to a disease other than MS.
2. Pregnancy or planned pregnancy within the upcoming study period, up to 7 months (includes the optional extension part).
3. Have an ongoing infection that subjectively affects their MS state, as judged by the Investigator.
4. Have received botulinum toxin injection for spasticity within the last 4 months.
5. Have symptoms or illness that make it difficult to participate in the study, as judged by the Investigator.
6. Having planned surgery or other treatment within the coming study period of up to 7 months that makes it difficult to participate in the study, as judged by the Investigator.
7. Subjects with uncontrolled wound infections or infections in the skin of the treated leg.