18 and older, any sex, with Complex Regional Pain Syndrome (CRPS). Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Change From Baseline to Week 12 in the Average Pain Intensity Score (Weekly Average of Pain Values Recorded Daily in the Electronic Diary)Primary· From the Baseline Phase (Day -7 to Day -1) to Week 12
In the Baseline Phase and in Treatment Period A/Follow-up Period 1, participants were asked to assessed their average CRPS-related pain on an 11-point numerical rating scale (NRS) - from 0 = "no pain" to 10 = "pain as bad as you can imagine" and report it once daily (in the evening, 24-hour recall) in an electronic diary.
Changes from baseline (average for the Baseline Phase) to the weekly average for Week 12 were calculated.
Group
Value
95% CI
Neridronic Acid - Treatment Period A
-1.28
± 0.270
Placebo - Treatment Period A
-1.71
± 0.268
Adverse events — posted to ClinicalTrials.gov
Time frame: Adverse events were documented from the time of enrollment (i.e., the time the informed consent form was signed) up to the time of the last protocol scheduled contact, i.e., date of last visit/contact (could be a phone call, e.g., in case of withdrawal). Only treatment emergent adverse events (TEAEs, i.e., those reported from baseline (after first administration of study medication) are reported in the tables below..
Reporting threshold: 2%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
Baseline to Week 26: Placebo TPA
Serious: 3/51 (6%)
Deaths: 0/51
Baseline to Week 26: Neridronic Acid TPA
Serious: 2/48 (4%)
Deaths: 0/48
Week 26 to Week 52: Placebo TPA
Serious: 0/43 (0%)
Deaths: 0/43
Week 26 to Week 52: Placebo TPA, Neridronic Acid TPB
The aim of this trial was to investigate the efficacy and safety of intravenous neridronic acid in subjects with Complex Regional Pain Syndrome (CRPS).
The trial consisted of an Enrollment Period lasting up to 60 days, Treatment Period A consisting of 4 infusions (neridronic acid 100 mg or placebo) over 10 days, and a Follow-up Period 1 until Week 26. At Week 26, participants meeting the pre-specified criteria entered the open-label Treatment Period B with 4 additional infusions (neridronic acid) over 10 days and follow-up visits until Week 52. Participants not meeting the pre-specified criteria to continue into Treatment Period B continued in Follow-up Period 2 until Week 52.
Publications & conference data
2 peer-reviewed publications reference this trial (live from Europe PMC):
NCT03530345 — Efficacy and Safety of Intravenous Neridronic Acid in CRPS
· Phase 3
· terminated
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Publications: Europe PMC API search by NCT ID, retrieved 9 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Grünenthal GmbH
Last refreshed: 5 August 2020
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT03560986.