Clinical Trial on Complex Regional Pain Syndrome I (CRPS I) - Clinical Trials Registry

Study Overview

Status

Not yet recruiting

Conditions

Complex Regional Pain Syndrome I (CRPS I)

Detailed Description

The primary objective of the registry is to evaluate the long-term effectiveness of IV neridronate across three outcome domains in participants who qualified in CRPS-RISE with early, warm CRPS-1 and a positive triple phase bone scan, following prior treatment with four infusions of neridronate 100 mg IV over approximately a 10-day period. The three outcome domains include, patient report of health status, CRPS-1 related clinical events, and disability status.

No neridronate treatment will be given as part of the registry and limited safety information will be collected. Participants will have received neridronate either through CRPS-RISE and/or through the Open Label Extension.

Study Type

Observational

Enrollment (Estimated)

270

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Name: CRPS-RiseRegistry
Phone Number: 877-834-5183
Email: CRPS-RiseRegistry@iqvia.com

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

Adult
Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

The registry target population for provisional enrollment includes all participants in CRPS-RISE, the parent trial of the Registry. After the completion of the last participant's last visit in CRPS-RISE and the unblinding of the trial, the Enrolled Study Cohort will be participants confirmed to have completed a four-infusion course of neridronate. The Enrolled Study Cohort will also include participants in the Open Label Extension study.

Description

Inclusion Criteria:

Participants from CRPS-RISE
1. Completion of four infusions of IP (neridronate 100 mg over a ~ 10-day period [or the renally modified dosing, as applicable] or placebo) in CRPS-RISE .
2. Completed CRPS-RISE with a final trial visit at Week 6 (Visit 8) or later.
  Participants who meet both criteria will be provisionally enrolled pending post-trial unblinding and be included in the Provisionally Enrolled Study Cohort.
  After CRPS-RISE last patient last visit unblinding, only participants who meet the following neridronate exposure criterion #3 will continue in registry follow-up and be included in the Enrolled Study Cohort:
3. Completion of 4-infusions of neridronate 100 mg over approximately a 10-day period in CRPS-RISE.
Participants from the Open Label Extension (OLE)
1. Completion of 4 infusions of neridronate 100 mg over approximately a 10-day period (or the renally modified dosing, as applicable) in the OLE.
2. Completed OLE with a final trial visit at Week 6 (Visit 8) or later.

Exclusion Criteria:

There are no exclusion criteria.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Provisionally Enrolled Study Cohort Participants provisionally enrolled in the registry. (Note: Participants provisionally enrolled who do not meet this neridronate-exposure criterion will not continue registry follow-up.)
Enrolled Study Cohort Participants who have consented to participate and meet all inclusion criteria including confirmation of completing four infusions of neridronate.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline to each registry assessment of average pain in the past 24 hours. Time Frame: Every 3 months from enrollment until up to 2 years after entry.	Average pain (24-hour recall) reported on an 11-point numeric rating scale. This is recorded every 90 days from entry.	Every 3 months from enrollment until up to 2 years after entry.
Time to loss of benefit where benefit is 50% reduction in average pain intensity from baseline to Week 12 of the CRPS-RISE trial. Time Frame: Every 3 months from enrollment until up to 2 years after entry.	Each patient reported registry assessment of average pain in the past 24 hours will use an 11 point numeric rating scale. The analysis will be limited to participants who experienced benefit. Data will be summarized as Kaplan-Meier estimates.	Every 3 months from enrollment until up to 2 years after entry.
Change from baseline to each registry assessment in CRPS Severity Score Self-Report (CSS-SR) total score and individual items. Time Frame: Every 3 months from entry to up to 24 months of participation.	The CSS-SR is designed as a patient self-report questionnaire to assess the severity of CRPS signs and symptoms using plain language to assess 13 concepts.	Every 3 months from entry to up to 24 months of participation.
Change from baseline to each registry assessment in Patient Global Impression of Severity (PGI-S). Time Frame: Every 3 months from enrollment until up to 2 years after entry.	The 6-point PGI-S is an overall assessment of the participant's perception of the severity of their CRPS condition at the time of the assessment. Participants will respond to the question "How would you rate the symptoms of your CPRS at this time." Possible responses are scored from 0 to 5 representing none, minimal, mild, moderate, severe, very severe.	Every 3 months from enrollment until up to 2 years after entry.
Change from baseline to each registry assessment in each of the Short Form 12 Health Survey (SF-12, Acute Version 2) domains, Physical Component Score (PCS), Mental Component Score (MCS), and individual items. Time Frame: Every 3 months from enrollment until up to 2 years after entry.	The SF-12 is a widely used measure of general health status used in observational studies across a broad range of disease areas. It is a shortened version of the SF-36 V2.0 and yields 8 domain scores and a Physical Component Summary and Mental Component Summary. Each domain score is calculated by transforming raw responses to a 0-100 scale, where higher scores indicate better health status.	Every 3 months from enrollment until up to 2 years after entry.
Change from baseline to each registry assessment in Daily Sleep Interference Scale (DSIS) in the past 24 hours on an 11-point numeric rating scale. Time Frame: Every 3 months from enrollment until up to 2 years after entry.	The DSIS is a single-item scale that assesses "how much did your pain interfere with your sleep during the past 24 hours?" (0 = did not interfere; 10 = completely interfered	Every 3 months from enrollment until up to 2 years after entry.
CRPS-1 Related Clinical Events during the 3 months preceding each registry assessment. Time Frame: Every 3 months from enrollment until up to 2 years after entry.	The CRPS-1 Treatment Checklist was developed for this registry to assess commonly used pharmacologic treatments (e.g., opioids, neuropathic pain agents, ketamine, NSAIDs, bisphosphonates, corticosteroids, and topicals),interventional procedures (e.g., spinal cord or dorsal root ganglion stimulation, peripheral nerve stimulation, stellate/lumbar sympathetic blocks, sympathetic ablation/sympathectomy, intrathecal pump implant, and Bier block), and non-invasive rehabilitation therapies (e.g., physical therapy, occupational therapy, mirror visual feedback, psychological therapies, scrambler therapies or acupuncture). Participants select all CRPS-related treatments used in the past 3 months. The checklist will also record participation in the open-label clinical trial and is intended for descriptive evaluation of long-term CRPS-1 treatments with a focus on resource intensive events. The outcome domain assesses the long-term effectiveness of neridronate through patient reports.	Every 3 months from enrollment until up to 2 years after entry.
Disability Status Time Frame: Every 3 months from enrollment until up to 2 years after entry.	During the 3 months preceding each registry assessment the participant reported applying for or being on short-term disability, long-term disability, or workers compensation. As a binary endpoint, it will be summarized as frequencies and percentages. The domain assesses the long-term effectiveness of neridronate through patient reports of short-term disability, long-term disability, and workers compensation.	Every 3 months from enrollment until up to 2 years after entry.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Healthcare Use and Costs (Provisional) Time Frame: Every 3 months from enrollment until up to 2 years after entry.	The potential for inclusion of linked health care claims and electronic health record data will be enabled by having participants consent to tokenizing their identifying information.	Every 3 months from enrollment until up to 2 years after entry.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Ambros Therapeutics, Inc.

Investigators

Principal Investigator: Joel Castellanos, MD, UCSD

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 16, 2026

Primary Completion (Estimated)

April 16, 2029

Study Completion (Estimated)

April 16, 2029

Study Registration Dates

First Submitted

August 31, 2026

First Submitted That Met QC Criteria

September 3, 2026

First Posted (Actual)

September 10, 2026

Study Record Updates

Last Update Posted (Actual)