Study of AxoGuard® Nerve Cap and Neurectomy for Treatment of Symptomatic Neuroma & Prevention of Recurrent Neuroma Pain (REPOSE)

A Multicenter, Prospective, Randomized and Subject Blinded Comparative Study of AxoGuard® Nerve Cap and Neurectomy for the Treatment of Symptomatic Neuroma and Prevention of Recurrent End-Neuroma Pain

Comparing safety, pain, user experience, healthcare economic costs, work productivity, impairment and quality of life outcomes between Axoguard® Nerve Cap and neurectomy in the treatment of symptomatic neuromas in the foot or ankle. Study consists of 86 subjects randomized between the treatment groups followed for 12 months.

Study Overview

• Status: Completed
• Conditions: Symptomatic Neuroma; Chronic Nerve Pain; Morton's Neuroma
• Intervention / Treatment: Device: AxoGuard® Nerve Cap; Procedure: Standard Neurectomy

• Study Type: Interventional
• Enrollment (Actual): 86
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90063
      • New Hope Podiatry Group
  • Florida
    • Saint Augustine, Florida, United States, 32080
      • Anastasia Medical Group
  • Georgia
    • Roswell, Georgia, United States, 30076
      • EHI Clinical Research
  • Illinois
    • O'Fallon, Illinois, United States, 62269
      • Gateway Clinical Trials
    • Rockford, Illinois, United States, 61107
      • OrthoIllinois
    • Springfield, Illinois, United States, 62704
      • Foot and Ankle Center of Illinois
  • Ohio
    • Columbus, Ohio, United States, 43210
      • The Ohio State University
  • Texas
    • Austin, Texas, United States, 78746
      • Austin Foot and Ankle Specialists
    • Denton, Texas, United States, 76210
      • Complete Foot and Ankle Care of North Texas
    • Fort Worth, Texas, United States, 76104
      • JPS Health Network
  • Utah
    • Saint George, Utah, United States, 84770
      • Foot & Ankle Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria (Potential Subjects must):

1. Be able and willing to provide documented informed consent prior to the conduct of any study procedures;
2. Be an adult male or non-pregnant female ≥ 18 years of age;
3. Report baseline pain scores of >65mm on a 100mm Visual Analog Scale (VAS) at screening;
4. Have a documented diagnosis of symptomatic neuroma of at least one interdigital nerve in the foot which cannot be repaired to a distal nerve end;

5. Must have the of the following:

   • Pain with at least 3 of the following characteristics: burning, sharp, shooting, electric, parasthesias, numbness, cold intolerance;
   • Symptoms in a defined neural anatomic distribution
   • History of nerve injury or suspected nerve injury

   Must have at least 1:

   • Positive response to local anesthetic injection
   • US or MRI confirmation of neuroma
6. Be candidates indicated for surgery to address a symptomatic neuroma;
7. Have sufficient healthy soft tissue available to adequately cover the Axoguard® Nerve Cap;
8. In the surgeon's opinion, be likely to achieve complete resection of the symptomatic neuroma and be able to undergo implantation with the Axoguard® Nerve Cap or complete the neurotomy procedure in the control group;
9. Be willing and able to comply with all aspects of the treatment and evaluation schedule over a 12-month duration.

Exclusion Criteria (Potential Subjects must not):

1. Have undergone surgical treatment of pain from symptomatic neuroma in the target nerve(s)on three or more occasions;
2. Have biomechanical pathology and associated pain (such as plantar fasciitis, bursitis, sesamoid bone pain, tendinitis, etc);
3. Have a life expectancy of less than 12 months;
4. Have a history of or planned radiotherapy in the area of the end-neuroma;
5. be contraindicated for soft tissue implants.; this includes but is not limited to any pathology that would limit the blood supply; compromise healing or indicate the presence of a local infection;
6. Have a history of chronic ischemic conditions of the extremity;
7. Have a diagnosis of type 1 Diabetes Mellitus; or uncontrolled Type 2 Diabetes Mellitus (at the discretion of the investigator);
8. Have a history of diabetic neuropathy;
9. Be undergoing or expected to undergo treatment with chemotherapy, radiation therapy, or other known treatment which affects the growth of neural and/or vascular system;
10. Be immunosuppressed, immunocompromised or have planned immunosuppressive therapy within 12 months following the study procedure;
11. Have a History of congenital neuropathy or compressive neuropathy affecting the target limb;
12. Have a history of prior surgical management of more proximal compressive neuropathies or spinal conditions (e.g. spinal stenosis) not related to the symptomatic neuroma that affect the target limb;
13. Currently use or likely need to use medication during the study known to impact nerve regeneration or to cause peripheral neuropathy;
14. Be pregnant or plan to become pregnant during the duration of the study;
15. Be or have been enrolled in another interventional study within 30 days prior to consenting;
16. Have a known allergy to anesthetic agents;
17. Have a known sensitivity to porcine derived materials; or
18. Be, in the opinion of the Investigator, unsuitable for inclusion in the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: AxoGuard® Nerve Cap; Porcine derived extracellular matrix (ECM) based Nerve Termination Device. Excision of symptomatic neuroma of the foot or ankle with placement of Axoguard Nerve Cap over the proximal stump of the nerve.	Device: AxoGuard® Nerve Cap; Entubulation of the nerve stump into the AxoGuard® Nerve Cap following surgical excision of symptomatic neuroma
Active Comparator: Standard Neurectomy; Standard surgical treatment for symptomatic neuroma of the foot or ankle entailing neuroma excision (without placement of Axoguard Nerve Cap).	Procedure: Standard Neurectomy; Surgical excision of symptomatic neuroma

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Visual Analog Scale (VAS) For Pain Score at 12 Post-operative Months in Comparative Phase Subjects	The Visual Analog Scale (VAS) For Pain is a patient reported outcomes scale whereby the patient indicates his/her current pain level by making a mark on a continuous horizontal 10-centimeter (100 millimeter) line. The distance from the 0 millimeter to the patient's mark corresponds to the amount of pain the participant is currently experiencing. VAS for Pain data are recorded as the number of millimeters from the left of the line to the patients mark across the range of 0-100 millimeters, with 0 millimeter representing "no pain" and 100 millimeters representing "the worst pain imaginable".	12 months
The Rate of Procedure- or Device-related Serious Adverse Events (SAEs) Through 3 Months	The primary safety endpoint will compare the rate of SAEs related to the procedure or device between treatment groups. The rate of serious adverse events for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	3 months
The Rate of Procedure- or Device-related Adverse Events (AEs) or Unanticipated Adverse Device Effects (UADEs) Through 3 Months	The primary safety endpoint will compare the rate of procedure- or device-related AEs or UADEs between treatment groups. The rate of events or effects for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Change From Baseline of Patient Reported Outcome Measurement Information System (PROMIS®) Pain Behavior Scale Score at Month 12	The Patient Reported Outcome Measurement Information System (PROMIS®) - Pain Related Measures is a set of person-centered measures that evaluates and monitors a patient's physical health and pain. The PROMIS - pain related measures include domains evaluating fatigue, pain intensity, paint interference, sleep Disturbance, and Pain Behavior. Short forms containing fixed sets of 4-10 items or questions are included for each domain. All PROMIS scores are presented as T-scores where the T-score is the standardized score with a mean of 50 (range 20-80) and a standard deviation of 10. Higher scores indicate more of the concept being measures where sometimes the concept is desirable (e.g., physical function) and sometimes this it is undesirable (e.g., fatigue). PROMIS instruments are scored using item-level calibrations based on response patterns by HealthMeasures Scoring Service.	12 months
Change in Foot Health Status Questionnaire (FHSQ) General Foot Health Scale at 12 Post-operative Months Compared to Baseline.	The Foot Health Status Questionnaire (FHSQ) measures foot health related to quality of life based on responsiveness in overall foot health status in 4 subscale areas (foot function, foot health, footwear and foot pain). The FHSQ is comprised of 13 questions. The questionnaire is self-administered. Subscale ratings are summed and the FHSQ score is reported as 0 (poorest state of foot health) to 100 (optimal foot health) with higher scores reflecting better foot health and quality of life.	12 months
As-Prescribed Opioid Medication	Change from pre-operative baseline in quantity of pain medication prescribed via morphine milligram equivalent (MME) at 12 months Opioid pain medications prescribed were converted to morphine milligram equivalent (MME) where such conversions are available to summarize pain medications by quantity of use.	12 Months
As-Taken Medication	Change from baseline in average daily quantity of pain medication taken via the Medication Quantification Scale (MQS) at 12 months. A daily pain medication log was provided to each participant to take home and complete each day and was collected at all visits. For opioid and non-opioid pain medications, the Medication Quantification Scale (MQS) Version III is a validated tool used to quantify the complexity and detriment of pain medication regimens. It calculates a single numeric value by combining medication detriment weights (ranging from 1.1 to 4.5) with dosage levels (scaled from 1 for subtherapeutic use to 4 for supratherapeutic use). A higher MQS score indicates greater potential medication detriment and/or dosage intensity. At 12 months, the study assessed changes from baseline in patients' average daily MQS scores.	12 Months
Rate of Recurrence of Symptomatic Neuroma	Symptomatic neuroma recurrence was defined as: VAS pain score higher at 12 months than baseline; Opioid medications (MME) higher at 12 months than baseline; Participant-reported pain >1 (on scale of 0-10) at least once between 9 months and 12 months. Participants experiencing all three of the criteria were determined to have symptomatic neuroma recurrence.	12 Months
Total Reported Pain From Baseline to 12 Months	Total pain experienced by participants over the course of study follow-up was calculated from the area under the curve (AUC) of daily pain log scores reported on a 0-10 numerical rating scale. An AUC value was calculated for each participant and normalized to the total possible AUC based on the number of log entries reported for that participant. The AUC scores are reported as a proportion of the total possible AUC (on a scale of 0-1) for a participant and difference in mean treatment group values tested by a t-test.	12 Months
The Rate of Procedure- or Device-related Serious Adverse Events (SAEs) Through 6 Months	The secondary safety endpoint will compare the rate of procedure- or device-related SAEs between treatment groups. The rate of serious adverse events for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	6 Months
The Rate of Procedure- or Device-related Adverse Events (AEs) or Unanticipated Adverse Device Effects (UADEs) Through 6 Months	The secondary safety endpoint will compare the rate of procedure- or device-related AEs or UADEs between treatment groups. The rate of events or effects for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	6 Months
The Rate of Procedure- or Device-related Serious Adverse Events (SAEs) Through 9 Months	The secondary safety endpoint will compare the rate of procedure- or device-related SAEs between treatment groups. The rate of serious adverse events for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	9 Months
The Rate of Procedure- or Device-related Adverse Events (AEs) or Unanticipated Adverse Device Effects (UADEs) Through 9 Months	The secondary safety endpoint will compare the rate of procedure- or device-related AEs or UADEs between treatment groups. The rate of events or effects for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	9 Months
The Rate of Procedure- or Device-related Serious Adverse Events (SAEs) Through 12 Months	The secondary safety endpoint will compare the rate of procedure- or device-related SAEs between treatment groups. The rate of serious adverse events for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	12 Months
The Rate of Procedure- or Device-related Adverse Events (AEs) or Unanticipated Adverse Device Effects (UADEs) Through 12 Months	The secondary safety endpoint will compare the rate of procedure- or device-related AEs or UADEs between treatment groups. The rate of events or effects for a given timepoint is given as the number of participants with one or more events up to that timepoint out of the population at risk.	12 Months

Collaborators and Investigators

• Sponsor: Axogen Corporation

Study record dates

Study Major Dates

• Study Start (Actual): October 10, 2018
• Primary Completion (Actual): July 17, 2023
• Study Completion (Actual): July 17, 2023

Study Registration Dates

• First Submitted: May 6, 2019
• First Submitted That Met QC Criteria: May 6, 2019
• First Posted (Actual): May 7, 2019

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 17, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Nervous System Diseases; Wounds and Injuries; Peripheral Nerve Injuries; Peripheral Nervous System Disease; Trauma - Nervous System; Nerve Repair; Surgical Treatment of Pain; Foot Neuroma; Foot Pain; Nerve Foot Pain
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Musculoskeletal Diseases; Nervous System Diseases; Neoplasms; Neuromuscular Diseases; Joint Diseases; Peripheral Nervous System Diseases; Neoplasms by Histologic Type; Neoplasms, Nerve Tissue; Nerve Sheath Neoplasms; Foot Diseases; Metatarsalgia; Morton Neuroma; Neuralgia; Neuroma
• Other Study ID Numbers: CAP-CP-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No