Pilot Study of the α Prototype NIMBLE System: Feasibility, Safety, and Initial Performance in Non-Invasive Detection of Coronary In-Stent Restenosis

NCT06968858 | Recruiting Phase 1 DMC

• 1 other identifier: NDX-0001
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The NIMBLE-I study is a prospective, unicentric, single arm, feasibility clinical trial designed to evaluate a novel medical device for the non-invasive monitoring of coronary stents. The study is being conducted at the Hospital Germans Trias i Pujol in Badalona, Spain, under the supervision of Dr. Oriol Rodríguez Leor, an experienced interventional cardiologist. It is sponsored by NIMBLE Diagnostics, a company developing the NIMBLE system-a non-ionizing, non-invasive prototype based on microwave interferometry (MWI). The motivation behind the study stems from the clinical challenge of detecting in-stent restenosis (ISR), a common complication following stent implantation that affects up to 10% of patients. Current diagnostic methods typically rely on invasive procedures such as coronary angiography or intravascular imaging, which are resource-intensive and carry procedural risks. The NIMBLE system has the potential to address this need by providing a safe, fast, and non-invasive alternative capable of detecting structural changes around coronary stents. The primary objective of the NIMBLE-I study is to assess the technical feasibility of the NIMBLE device in a real-world clinical setting. Secondary objectives include evaluating the safety of the device, generating preliminary data on its effectiveness by comparing its measurements with those obtained from invasive coronary angiography-the reference standard for diagnosing ISR-and collecting usability data to inform improvements in future versions of the device. The study is designed to enroll up to 120 patients of whom 30 will undergo an OCT examination to evaluate the ability of the α prototype to measure ISR. Participants must be adults with previously implanted coronary stents who present with symptoms suggestive of ISR-such as chest pain or ischemic changes on an electrocardiogram-and are already scheduled for diagnostic angiography. Patients with contraindications such as pregnancy, implanted electronic devices (like pacemakers), or anatomical limitations that preclude correct device positioning will be excluded. The procedure begins with obtaining informed consent from eligible patients. Prior to the scheduled angiographic procedure, the NIMBLE system is used to perform a non-invasive scan. The device, which includes biocompatible transducers, is placed externally over the patient's chest at the level of the coronary stent. Data acquisition does not interfere with standard clinical care. After the NIMBLE scan, patients proceed with their routine coronary angiography as per standard of care. Importantly, operators performing the angiography remain blinded to the results of the NIMBLE device. Data analysis will focus on two main areas. The primary endpoint is the successful completion of NIMBLE measurements without device-related adverse events. Secondary endpoints include the agreement between NIMBLE output-specifically, a calculated metric called %RIS (percent restenosis intrastent)-and angiographic findings. Statistical methods will be applied to assess sensitivity, specificity, correlation, and agreement between modalities. Usability feedback from clinical operators will also be collected to inform future device iterations. The study complies with all applicable regulatory and ethical guidelines, including ISO 14155 and the European Medical Device Regulation (MDR 2017/745). It has been approved by the relevant ethics committee and competent authority before its launch. Each patient's data will be anonymized and handled according to Good Clinical Practice (GCP) standards. Expected outcomes from the NIMBLE-I study include confirmation that the device can be safely and effectively used in a clinical context and that its diagnostic output correlates with invasive imaging findings. Positive results will lay the groundwork for a pivotal clinical trial and advance the development of a tool that could significantly improve the follow-up of patients with coronary stents. Ultimately, this technology could reduce the need for invasive procedures and enable earlier detection of stent-related complications in an outpatient setting.

Conditions

In-stent Restenosis; Stent Fracture; Stent Complication

Keywords

non-invasive; microwave; prototype; nimble; in-stent restenosis

Outcome Measures

Primary Outcomes (2)

• Feasibility

  Feasibility will be assessed by the proportion of enrolled patients in whom the NIMBLE System measurement can be successfully completed and a usable diagnostic output is obtained.

  prior angiography

• Safety

  Absence of device-related adverse events

  7 days after Nimble test

Secondary Outcomes (2)

• Performance

  DWithin 24 hours before invasive coronary angiography (single time point assessment)

• Usability

  User (operator) questionnaire will be administered immediately after the NIMBLE System measurement in the first and last enrolled patients. Patient questionnaire will be administered to every participant immediately after their NIMBLE measurement, on the

Study Arms (1)

Experimental

EXPERIMENTAL

Patients undergoing NIMBLE System measurement prior to coronary angiography

Diagnostic Test: NIMBLE test

Interventions

NIMBLE test DIAGNOSTIC_TEST

Non-invasive assessment of ISR with the NIMBLE System (Microwave Interferometry)

Experimental

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Prior implantation of one or more coronary stents
• Clinical symptoms suggestive of stent failure (e.g., chest pain, ischemic ECG changes)
• Undergoing scheduled coronary angiography
• Informed consent provided

You may not qualify if:

• Pregnancy
• Implanted electronic devices (e.g., pacemakers) that may interfere with MWI
• Inability to provide consent
• Chest conditions preventing correct positioning of the device

Sponsors & Collaborators

• Nimble Diagnostics S.L.: lead

Study Sites (1)

Hospital Universitari Germans Trias i Pujol

Badalona, Catalonia, 08916, Spain

RECRUITING

Related Links

• NIMBLE Diagnostics webpage

Study Officials

• Oriol Rodriguez-Leor, MD, PhD

  Germans Trias i Pujol Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Masking Details: The NIMBLE System measurement is performed prior to the invasive coronary angiography, ensuring that the operator conducting the NIMBLE assessment is blinded to the results of the reference standard (angiography and, when applicable, OCT). This approach minimizes potential diagnostic bias and preserves the objectivity of the non-invasive measurement.
• Purpose: DEVICE FEASIBILITY
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: All enrolled participants will undergo a single, non-invasive measurement with the NIMBLE System prior to their scheduled invasive coronary angiography. No randomization or comparison groups are included. A subset of 30 participants will also undergo optical coherence tomography (OCT) to provide additional reference data. Usability and safety assessments will be conducted based on operator and patient feedback.

Study Record Dates

• First Submitted: April 24, 2025
• First Posted: May 13, 2025
• Study Start: September 12, 2024
• Primary Completion: September 1, 2025
• Study Completion: October 1, 2025
• Last Updated: May 13, 2025

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)