Investigational implantable epidural spinal stimulation system for blood pressure instability after spinal cord injury, in the Empower BP pivotal study. Hardware specifications are not published in the sources read.
Independent, source-linked catalog sheet. Not a manufacturer-issued datasheet, regulatory decision or instructions for clinical use. Human evidence does not establish approval. Source-specific restrictions, conflicts and missing specifications are retained below.
ONWARD ARC-IM implantable spinal stimulation
ARC-IM is ONWARD’s investigational implanted spinal cord stimulation system, an IPG with a thoracic epidural lead, being tested for blood pressure instability after spinal cord injury. It is not approved. Hardware dimensions and contact counts are Unreported because the sources read do not give them. The external ARC-EX system is out of scope.
Identity
Field
Value and source scope
Device
ONWARD ARC-IM System: implanted neurostimulator (IPG) and implanted epidural lead (thoracic lead) [1][2]
Manufacturer
ONWARD Medical N.V. (US sponsor entity ONWARD Medical, Inc.) [2][3]
Interface class
Epidural spinal cord stimulation lead with an implanted neurostimulator [1][2]
Origin
Investigational device; FDA IDE approved August 18, 2025 for the Empower BP pivotal study [2]
First demonstrated
Unreported
First human implant
Unreported
Species studied
Human [1][3]
Regulatory status
Investigational, not approved. FDA Breakthrough Device designation in 2020 for leg motor function and later for blood pressure and trunk control [1][4]
Function
Targeted, programmed stimulation of the spinal cord for blood pressure instability after spinal cord injury; ONWARD describes it as aimed at the thoracic Hemodynamic Hotspot [1][5]
Target tissue
Thoracic spinal cord, epidural space; ONWARD cites lesion levels C3-T6, AIS A-D, for the blood pressure indication [1][5]
Geometry and architecture
Field
Value and source scope
Interface type
Purpose-designed epidural lead for spinal cord injury connected to a purpose-designed neurostimulator [1][5]
Array layout
Unreported
Electrode count
Unreported
Pitch
Unreported
Electrode lengths
Unreported
Shank width and thickness
Unreported
Tip and exposed site geometry
Unreported
Contact coating
Unreported
Insulation
Unreported
Insertion method
Unreported
Anchoring and fixation
Unreported
Electrode and channel physics
Field
Value and source scope
Exposed site area
Unreported
Electrode material
Unreported
Impedance (with measurement frequency)
Unreported
Noise floor or SNR
Unreported
Recording modality
Unreported
Sampling rate
Unreported
Stimulation capability
Unreported
Charge injection limit
Unreported
Reference and ground
Unreported
Tissue interface and bioresponse
Field
Value and source scope
Target tissue
Unreported
Insertion trauma and BBB disruption
Unreported
Vascular disruption risk
Unreported
Micromotion sensitivity
Unreported
Gliosis and encapsulation
Unreported
Neuron loss near sites
Unreported
Foreign-body response mitigation
Unreported
Typical failure modes
Unreported
System architecture
Field
Value and source scope
Onboard electronics
Unreported
Data path
Unreported
Telemetry bandwidth
Unreported
Sampling rate
Unreported
Power
Unreported
Thermal management
Unreported
Packaging and hermeticity
Unreported
MRI compatibility
Unreported
Surgical complexity
Unreported
Output connectors
Unreported
Performance envelope
Field
Value and source scope
Acute yield
Unreported
Chronic yield
Unreported
Stability over time
Unreported
Longevity
Unreported
Revision and explant experience
Unreported
Adverse events
Unreported
Notable demonstrations
Unreported
Clinical and preclinical evidence
Field
Value and source scope
Human subjects
Empower BP: 60 participants planned (ESTIMATED) at about 20 centers across the US, Canada and Europe; ages 18 to 75 [2][3]
Primary effectiveness: participant-reported ADFSCI and seated blood pressure assessments at 3 months. Earlier feasibility results were published in Nature Medicine 2025 (Phillips et al.); numeric results were not extracted here [1][3]
Key limitations
Investigational. Lead contact count, dimensions, IPG size and battery are not in the sources read. The external ARC-EX system is not covered by this sheet [1]
Engineering tradeoffs
Field
Value and source scope
Strengths
Unreported
Limitations
Unreported
Scaling constraints
Unreported
Version boundary
The system as named in the 2025 IDE and the Empower BP registry record. Earlier feasibility configurations are not described.