Evaluation of IV AMBTX-01 (Neridronate) for Treatment of CRPS Type 1 (CRPS-RISE)

NCT ID: NCT07210515

Last Updated: 2025-10-07

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: PHASE3
• Total Enrollment: 270 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2026-03-31
• Study Completion Date: 2028-01-31

Brief Summary

Phase 3 Trial of AMBTX-01 (neridronate) for Complex Regional Pain Syndrome Type 1

Detailed Description

This is a multicenter, randomized, triple-blind, controlled trial, to assess the efficacy, safety, and tolerability of neridronate 400 mg IV in adult participants with the warm subtype of Complex Regional Pain Syndrome Type 1 (CRPS-1) and a positive triple phase bone scan (TPBS).

The total planned trial duration for each participant will be approximately up to 18 weeks and will include:

• Screening period of up to 6 weeks
• Treatment period on Days 1, 4, 7, and 10
• Post-treatment follow-up through week 12

Conditions

Complex Regional Pain Syndrome Type I

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

neridronate

400 mg AMBTX-01 infusion

Group Type: EXPERIMENTAL

Neridronate

Intervention Type: DRUG

neridronate 100 mg, given as a 2-hour infusion on Days 1, 4, 7, and 10.

Placebo

Placebo comparator

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DRUG

placebo comparator

Interventions

Neridronate

neridronate 100 mg, given as a 2-hour infusion on Days 1, 4, 7, and 10.

Intervention Type: DRUG

Placebo

placebo comparator

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

1. Male or female participant ≥ 18 years of age at time of Screening.

2. A diagnosis of CRPS-1 according to the clinical Budapest Criteria as recommended by the International Association for the Study of Pain (IASP), as well as no known peripheral nerve injury. Signs and symptoms of CRPS must apply to a single identified affected limb (i.e., arm, hand, wrist, leg, ankle or foot) and must demonstrate asymmetry with respect to the contralateral limb.

3. Single affected limb at the Screening and Randomization Visits meeting the following warm subtype criteria:

1. Edema in the affected limb

2. AND ≥ 2 of the following:

1. Obvious redness in the affected region relative to the same region on the contralateral limb on inspection

2. ≥ 1°C increase in temperature on the affected limb relative to the contralateral limb

3. Moderate-to-severe edema

4. CRPS symptoms ≤ 6 months since onset.

5. Increased uptake in the involved limb compared to the contralateral limb on TPBS (phase 2 and/or phase 3) during Screening. A historic scan not older than 3 months prior to Randomization Visit is acceptable, if available and of sufficient quality for a central read.

6. "Pain now" assessments of > 4 on the 11 point numerical rating scale in the CRPS affected limb.

7. Women of childbearing potential must:

1. Be nonpregnant.

2. Be nonlactating.

3. Agree to use a highly effective method of contraception and for at least 6 months following last investigational product administration.

Exception: Women exclusively engaging in same sex sexual activities are not required to meet this criterion.

Exclusion Criteria

1. A current or prior diagnosis of CRPS Type 2 or CRPS not otherwise specified (CRPS NOS), or whose CRPS has no known inciting event, or CRPS-1 without criteria of the warm subtype at the time of Screening.

2. ≥ 40 points on the Pain Catastrophizing Scale.

3. Prior use of neridronate or participation in a clinical study where the participant may have received neridronate.

4. Participants currently taking or planning to be treated with prohibited concomitant medications/therapies, or not likely able to follow the protocol restrictions for use of concomitant treatment.

5. Severely impaired renal function.

6. Hypocalcemia.

7. Vitamin D deficiency.

8. Significant dental findings such as an unhealed tooth extraction site.

9. Eye inflammation.

10. Significantly elevated liver-related lab tests or evidence of significant liver disease.

11. Clinically unstable cardiac disease.

12. Any known conditions, from 3 months prior to Screening Visit or to the Randomization Visit, that may interfere with the assessment of CRPS-1, CRPS-related pain, safety, or other trial assessments.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Ambros Therapeutics, Inc.

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Central Contacts

SVP, Clinical Operations

Role: CONTACT

clinicaltrials@ambrostx.com

+1 949-785-4954

Ambros Therapeutics, Inc

Role: CONTACT

Other Identifiers

AMBTX-01-301

Identifier Type: -

Identifier Source: org_study_id