A Phase 2 interventional study of Ciraparantag and Placebo in Healthy, sponsored by AMAG Pharmaceuticals, Inc.. Terminated at 3 sites in United States. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-04-20.
Sponsored by AMAG Pharmaceuticals, Inc. · Phase 2, Interventional, and Treatment
A randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of ciraparantag for reversal of anticoagulation induced by different anticoagulant drugs in generally healthy adults as measured primarily by an automated coagulometer device.
This is a randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of ciraparantag for reversal of anticoagulation induced by different anticoagulant drugs (edoxaban, apixaban or rivaroxaban) in generally healthy adults. Throughout the study, coagulation status will be determined by whole blood clotting time (WBCT), which will be measured primarily by the Perosphere Technologies' PoC Coagulometer and at selected timepoints using a manual testing method.
The study will be conducted in three separate cohorts; each cohort will evaluate the reversal of a different anticoagulant drug. Within each cohort, an initial group of subjects (Group 1) will be enrolled for evaluation of a target dose of ciraparantag. Depending on the efficacy and safety results from Group 1, a second group (Group 2) may be enrolled to evaluate a different dose of ciraparantag for that cohort.
AMAG Pharmaceuticals, Inc. is the lead sponsor of 24 studies on the registry; 2 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 5 (83%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Have any of the following findings at Screening:
Subjects receive 60 mg edoxaban orally once daily in the morning on Days 1 to 4. On Day 4, approximately 3 hours after administering edoxaban, study drug (ciraparantag or placebo) will be intravenously administered.
Drug: Ciraparantag · Drug: Placebo · Device: Point-of-Care Coagulometer (investigational device)
Subjects receive 10 mg apixaban orally every 12 hours on Days 1 to 3, with a final dose in the morning on Day 4. On Day 4, approximately 4 hours after administering apixaban, study drug (ciraparantag or placebo) will be intravenously administered.
Drug: Ciraparantag · Drug: Placebo · Device: Point-of-Care Coagulometer (investigational device)
Subjects receive 20 mg rivaroxaban orally once daily in the morning on Days 1 to 4. On Day 4, approximately 4 hours after administering rivaroxaban, study drug (ciraparantag or placebo) will be intravenously administered.
Drug: Ciraparantag · Drug: Placebo · Device: Point-of-Care Coagulometer (investigational device)
Ciraparantag: 180 mg, intravenous
Also known as: PER977, AMAG 977
Placebo: 0.9% sodium chloride, intravenous
Also known as: PBO
Perosphere Technologies' Point of Care (POC) Coagulometer Device will be used to measure whole blood clotting time.
Also known as: Coagulometer
Subjects Achieving WBCT ≤120% of Baseline
The primary efficacy endpoint is achieving a WBCT (measured by PoC coagulometer) ≤ 120% of baseline within 1 hour after administration of ciraparantag/PBO, which is subsequently sustained after 1 hour through at least 6 hours after ciraparantag/PBO dosing (Responder).
Time frame: Within 1 hour and sustained through 6 hours
Screening occurred between Oct 2021 and Aug 2023 at 3 phase 1 clinics. Subjects were enrolled into the cohorts listed below (i.e., no participants were enrolled in Cohort 2, Apixaban 10mg).
| Milestone | Cohort 1 (Edox) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) Cira 180 mg | Cohort 3 (Riva) PBO |
|---|---|---|---|---|
| Started | 6 | 12 | 13 | 6 |
| Completed | 6 | 12 | 12 | 6 |
| Not completed | 0 | 0 | 1 | 0 |
| Withdrew: Randomized, not dosed w ciraparantag, due to not meeting threshold for sufficient anticoagulation | 0 | 0 | 1 | 0 |
The primary efficacy endpoint is achieving a WBCT (measured by PoC coagulometer) ≤ 120% of baseline within 1 hour after administration of ciraparantag/PBO, which is subsequently sustained after 1 hour through at least 6 hours after ciraparantag/PBO dosing (Responder).
| Participants | Cohort 1 (Edox) Cira 180 mg | Cohort 1 (Edox) PBO | Cohort 3 (Riva) Cira 180 mg | Cohort 3 (Riva) PBO |
|---|---|---|---|---|
| Subjects Achieving WBCT ≤120% of Baseline | 0 | 1 | 0 | 0 |
Collected over Adverse events were monitored from the time the informed consent was signed through the last study visit / study completion which occurred five days after IP-dosing. Serious Adverse Events were reported through 30 days after the last dose of ciraparantag/placebo.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Cohort 1 (Edox) PBO | 0/6 (0%) | 0/6 (0%) | 0/6 (0%) |
| Cohort 3 (Riva) PBO | 0/6 (0%) | 0/6 (0%) | 0/6 (0%) |
| Cohort 1 (Edox) Cira 180 mg | 0/12 (0%) | 0/12 (0%) | 7/12 (58.3%) |
| Cohort 3 (Riva) Cira 180 mg | 0/12 (0%) | 0/12 (0%) | 3/12 (25%) |
| Enrolled Not Treated | 0/4 (0%) | 0/4 (0%) | 0/4 (0%) |
| Event | Cohort 1 (Edox) PBO | Cohort 3 (Riva) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) Cira 180 mg | Enrolled Not Treated |
|---|---|---|---|---|---|
| Feeling HotGeneral disorders | 0/6 | 0/6 | 2/12 | 3/12 | 0/4 |
| Infusion site erythemaGeneral disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| ConstipationGastrointestinal disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| Arthropod biteInjury, poisoning and procedural complications | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| Back painMusculoskeletal and connective tissue disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| Musculoskeletal painMusculoskeletal and connective tissue disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| Pain in extremityMusculoskeletal and connective tissue disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| PhlebitisVascular disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
| Paraesthesia oralGastrointestinal disorders | 0/6 | 0/6 | 0/12 | 1/12 | 0/4 |
| Abdominal tendernessGastrointestinal disorders | 0/6 | 0/6 | 1/12 | 0/12 | 0/4 |
Demographic analysis population utilized the Efficacy Population, consisting of 36 subjects randomized and dosed with ciraparantag or placebo.
| Age, Continuous(Years) | Cohort 1 (Edox) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) PBO | Cohort 3 (Riva) Cira 180 mg | Total |
|---|---|---|---|---|---|
| Mean | 44.7 ± 15.38 | 45.3 ± 14.46 | 43.5 ± 15.6 | 47.0 ± 14.76 | 45.4 ± 14.30 |
| Sex: Female, Male(Participants) | Cohort 1 (Edox) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) PBO | Cohort 3 (Riva) Cira 180 mg | Total |
|---|---|---|---|---|---|
| Female | 1 | 7 | 1 | 4 | 13 |
| Male | 5 | 5 | 5 | 8 | 23 |
| Ethnicity (NIH/OMB)(Participants) | Cohort 1 (Edox) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) PBO | Cohort 3 (Riva) Cira 180 mg | Total |
|---|---|---|---|---|---|
| Hispanic or Latino | 3 | 7 | 1 | 6 | 17 |
| Not Hispanic or Latino | 3 | 5 | 5 | 6 | 19 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Cohort 1 (Edox) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) PBO | Cohort 3 (Riva) Cira 180 mg | Total |
|---|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 | 0 | 0 |
| Asian | 0 | 1 | 0 | 0 | 1 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 |
| Black or African American | 1 | 2 | 4 | 1 | 8 |
| White | 5 | 9 | 2 | 11 | 27 |
| More than one race | 0 | 0 | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 | 0 |
| Baseline Whole Blood Clotting Time (WBCT) as measured by PoC Coagulometer(seconds) | Cohort 1 (Edox) PBO | Cohort 1 (Edox) Cira 180 mg | Cohort 3 (Riva) PBO | Cohort 3 (Riva) Cira 180 mg | Total |
|---|---|---|---|---|---|
| Mean | 235.2 ± 37.69 | 239.0 ± 35.76 | 213.7 ± 30.85 | 235.4 ± 28.52 | 232.9 ± 32.80 |
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AMAG Pharmaceuticals, Inc.