Safety study of a spider silk nerve guide for repairing large nerve gaps in humans
| ISRCTN | ISRCTN29838295 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN29838295 |
| Universal Trial Registration Number | U1111-1323-9544 |
| Sponsor | Newrotex Limited |
| Funder | UK Research and Innovation |
- Submission date
- 27/02/2026
- Registration date
- 02/03/2026
- Last edited
- 02/03/2026
- Recruitment status
- No longer recruiting
- Overall study status
- Ongoing
- Condition category
- Surgery
Plain English summary of protocol
Background and study aims
Peripheral nerves are the nerves outside the brain and spinal cord. They control movement and sensation (such as touch and pain). These nerves can be damaged by trauma or during surgery, especially cancer surgery. When a nerve is cut and there is a large gap between the two ends, it cannot simply be stitched back together. This can result in permanent numbness, weakness, pain and reduced quality of life.
The current standard treatment for large nerve gaps is called an autograft. This involves taking a healthy nerve from another part of the patient’s body and using it to bridge the gap. This causes permanent loss of function at the donor site and can lead to complications such as pain, infection and poor wound healing. Recovery is often incomplete.
A new device called SilkAxons™ has been developed to help nerves regrow across large gaps. It is made from spider silk fibres, which act as a scaffold (support structure) to guide nerve growth. The silk is placed inside one of the patient’s own veins, which forms a natural tube around it. The silk gradually dissolves over time.
This study aims to find out whether SilkAxons™ is safe to use in humans for repairing large nerve gaps. It will also explore whether standard clinical tests can reliably measure nerve recovery in this setting to help plan larger future studies.
Who can participate?
Patients aged 18 to 55 years scheduled for surgery that will involve cutting a peripheral nerve and creating a large gap (between 3 cm and 10 cm) that cannot be directly repaired with stitches. Examples include nerve biopsy, tumour removal or planned nerve graft procedures.
What does the study involve?
This is a small, single-centre study taking place in Panama. During the planned operation, once the nerve has been cut, the surgeon will:
1. Take a short section of one of the patient’s own veins.
2. Insert the SilkAxons™ fibres into the vein.
3. Use this vein-and-silk construct to bridge the nerve gap.
Participants will be followed for 12 months after surgery. Follow-up visits will take place at 1, 3, 6 and 12 months. At these visits, doctors will:
1. Check for any complications or side effects.
2. Assess sensation using touch tests.
3. Assess muscle strength if the nerve controls movement.
4. Perform electrical nerve tests at selected visits.
5. Ask participants to complete questionnaires about pain and overall improvement.
The main aim is to monitor safety, particularly in the first 6 months while the silk device dissolves (expected within about 3 to 4 months).
What are the possible benefits and risks?
This is an early-stage (“first-in-human”) study. The main benefit is to help determine whether this new device is safe and suitable for further testing. If successful, it could lead to improved treatments for people with severe nerve injuries in the future.
The device may help guide nerve regrowth and improve recovery, but this cannot be guaranteed. Participants may benefit from close follow-up and monitoring.
Risks include standard surgical risks such as infection, bleeding or poor wound healing. There may also be risks related to vein harvesting or a reaction to the silk implant. In rare cases, further surgery may be needed to remove the device.
Strict safety monitoring procedures are in place. The study will be paused or stopped if significant safety concerns arise.
Where is the study run from?
The Panama Clinic in Panama
When is the study starting and how long will it run?
August 2025 to December 2026
Who is funding and sponsoring the study?
UK Research and Innovation (UKRI) through the Horizon Europe Guarantee scheme
Who is the main contact?
Dr Alex Woods, alex.woods@newrotex.com
Contact information
Public, Scientific
Newrotex Ltd, Wood Centre for Innovation, Quarry Road
Oxford
OX3 8SB
United Kingdom
 ORCID ID |
0000-0001-5387-1705 |
|---|---|
| Phone | +44 (0)1865 548896 |
| alex.woods@newrotex.com |
Principal investigator
The Panama Clinic, Calle Ramon H. Jurado, Pacific Center, Torre A, piso 12 consultorio 1211, San Francisco Panamá, Ciudad de Panamá
Panama
00507
Panama
| Phone | +507 (0)310-1111 |
|---|---|
| drricardobermudez@gmail.com |
Study information
| Primary study design | Interventional |
|---|---|
| Allocation | N/A: single arm study |
| Masking | Open (masking not used) |
| Control | Uncontrolled |
| Assignment | Single |
| Purpose | Device feasibility, Treatment, Safety (First-in-Human) |
| Scientific title | First-in-human safety trial to evaluate the reconstruction of large gap nerve defects in humans using an implanted silk nerve guide |
| Study acronym | NSA1: SilkAxons |
| Study objectives | To assess the safety of a new peripheral nerve repair device (SilkAxons), and assess the feasibility of assessing large gap nerve regeneration. |
| Ethics approval(s) |
Approved 30/06/2025, Comité de Bioética en Investigación de The Panama Clinic (Centro Pacific Center, Torre A, piso 17 oficina 1714. Calle Ramon H Jurado-ciudad de Panamá, Panama, 00507, Panama; +507 (0)310-2414; comitebioeticatpc@thepanamaclinic.com), ref: EC-CBITPC-144 |
| Health condition(s) or problem(s) studied | Adults aged 18-55 years who are undergoing a surgical procedure that will generate a large gap (3-10 cm) in peripheral nerve discontinuity (sensory, motor or mixed) that cannot be directly repaired with suturing |
| Intervention | For adults aged 18-55 years who are undergoing a surgical procedure that will generate a large gap (3-10 cm) peripheral nerve discontinuity (sensory, motor or mixed) that cannot be directly repaired with suturing, for example, from autograft harvesting, nerve biopsy, neuroma or tumour excision. The nerve gap is to be repaired with the appropriate number of SilkAxons devices (a silk scaffold) inserted into an autologous vein graft taken from the surgical field. |
| Intervention type | Device |
| Phase | Phase II |
| Drug / device / biological / vaccine name(s) | SilkAxons |
| Primary outcome measure(s) |
|
| Key secondary outcome measure(s) |
|
| Completion date | 25/12/2026 |
Eligibility
| Participant type(s) | |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 55 Years |
| Sex | All |
| Target sample size at registration | 5 |
| Total final enrolment | 5 |
| Key inclusion criteria | 1. Participant is willing and able to give informed consent for participation in the trial 2. Between 18 and 55 years of age 3. Patient requires surgery that would require planned transection of a peripheral nerve, generating a “large gap” defect between 3 and 10 cm (e.g. nerve biopsy, autograft donor or tumour excision) 4. Transected nerve can be reconstructed at same operation as defect created 5. Sufficient distal skin sensation or measurable motor function present for transected nerve to be able to record effect of transection and subsequent recovery 6. In the Investigator’s opinion, is able and willing to comply with all trial requirements 7. Willing to attend sufficient follow-up assessments to determine the outcomes of the repair and comply with site-specific postoperative care procedures |
| Key exclusion criteria | 1. Their medical history includes disorders known to affect the peripheral nervous system (e.g., diabetes mellitus, chronic heavy alcohol use, toxic nerve lesions, polyneuropathy) 2. Their presentation includes any additional injury that could compromise nerve regeneration (e.g., vascular insufficiency to the harvested lower limb) 3. They are known to have a condition, which the Investigator believes may make implementation/interpretation of the protocol or results difficult 4. They have had previous conditions of the affected area that could affect the healing of the actual nerve injury 5. They have been treated with immunosuppressive or antineoplastic agents within 30 days prior to the enrolment 6. Known to be HIV positive from their medical history 7. Participated in another clinical investigation using an investigational new drug or device within 30 days prior to enrolment into this investigation 8. Uncooperative or unsuitable subject (e.g., language barrier, strong suspicion of inability to adhere to follow-up schedule) 9. Suspected or documented allergy to silk 10. Patient is pregnant, lactating, or intends to become pregnant during the study. 11. Medical history of previous vein stripping procedures at the intended surgical site 12. Planned nerve to undergo transection has no clear sensory distribution or measurable motor function based on clinical knowledge and examination |
| Date of first enrolment | 20/08/2025 |
| Date of final enrolment | 13/12/2025 |
Locations
Countries of recruitment
- Panama
Study participating centre
Panama
Panama
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|
Editorial Notes
27/02/2026: Study's existence confirmed by the Comité de Bioética en Investigación de The Panama Clinic.
