A Phase 2 interventional study of IMR-687 and Placebo in Sickle Cell Disease, sponsored by Cardurion Pharmaceuticals, Inc.. Completed at 13 sites in 2 countries. Open to participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2025-05-15.
Sponsored by Cardurion Pharmaceuticals, Inc. · Phase 2, Interventional, and Treatment
Study of IMR-687 in adult participants with sickle cell anemia (SCA) (homozygous HbSS or sickle-β0 thalassemia).
This is a proof-of-concept study in adult SCA participants, ages 18 to 55 years old, to examine the safety, tolerability, and pharmacokinetic (PK), as well as the potential pharmacodynamic (PD) effects and clinical efficacy, of IMR-687 across a range of doses.
IMR-687 was administered in 2 populations of participants with SCA: those who were not receiving hydroxyurea (HU) and those who were receiving a stable dose of HU according to standard of care.
1,134 studies on the registry are indexed under Anemia, Sickle Cell; 238 are open to participants now.
This study's enrollment of 100 is above the median of 40 across 769 interventional studies indexed under Anemia, Sickle Cell.
Browse Anemia, Sickle Cell studies →Cardurion Pharmaceuticals, Inc. is the lead sponsor of 12 studies on the registry; 2 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 4 (50%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A starting dose of IMR-687 50 mg with dose escalation after 4 or 12 weeks, up to 100 mg was administered to participants. Duration of administration was 16 (Week 17) or 24 weeks (Week 25).
Drug: IMR-687
A starting dose of IMR-687 100 mg with dose escalation after 4 or 12 weeks, up to 200 mg was administered to participants. Duration of administration was 24 weeks (Week 25).
Drug: IMR-687
Matching placebo was administered for 16 (Week 17) or 24 weeks (Week 25).
Drug: Placebo
Oral administration of IMR-687 once daily with or without HU.
Oral administration of placebo once daily with or without HU.
Number Of Participants With Treatment-emergent Adverse Events (TEAEs) And Serious Adverse Events (SAEs)
An adverse event (AE) was defined as any untoward medical occurrence in a clinical study participant administered a pharmaceutical product and which did not necessarily have to have a causal relationship with this treatment. An SAE was defined as any AE that resulted in 1 or more of the following outcomes: death, required or prolonged hospitalization, life-threatening, persistent or significant disability/incapacity, congenital anomaly or birth defect, or other medically important event. A summary of serious and all other non-serious AEs, regardless of causality, is located in the Reported Adverse Events module.
Time frame: Day 1 (after dosing) through up to Week 24
Pharmacokinetic (PK) Of Participants Who Did Not Concomitantly Receive HU: Maximum Plasma Concentration (Cmax) Of IMR-687
For PK assessments of participants who did not concomitantly receive HU, serial blood samples for IMR-687 plasma concentrations were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 25) assessments are presented.
Time frame: Day 1 and Week 25
PK Of Participants Who Did Not Concomitantly Receive HU: Area Under The Concentration-time Curve (AUC) From Time 0 To 24 Hours Postdose (AUC0-24h) Of IMR-687
For PK assessments of participants who did not concomitantly receive HU, serial blood samples for IMR-687 plasma concentrations were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 25) assessments are presented.
Time frame: Day 1 and Week 25
PK Of Participants Who Concomitantly Received HU: Cmax Of IMR-687
For PK assessments of participants who concomitantly received HU, serial blood samples for IMR-687 PK were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 17) assessments are presented.
Time frame: Day 1 and Week 17
PK Of Participants Who Concomitantly Received HU: AUC0-24h Of IMR-687
For PK assessments of participants who concomitantly received HU, serial blood samples for IMR-687 plasma concentrations were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 17) assessments are presented.
Time frame: Day 1 and Week 17
PK Of Participants Who Concomitantly Received HU: Cmax Of HU
For PK assessments of participants who concomitantly received HU, serial blood samples for HU PK were drawn predose and at 0.5, 1, 1.5, 3, 6, 8, and 10 hours after self-administration of the prescribed dose of HU. HU in the presence (end of treatment \[EOT\]: Week 17) or absence of IMR-687 (Baselines 1 and 2) are presented. HU concentration data were not sorted with respect to HU dose.
Time frame: Baseline (1 and 2) and Week 17
PK Of Participants Who Concomitantly Received HU: AUC0-24h Of HU
For PK assessments of participants who concomitantly received HU, serial blood samples for HU PK were drawn predose and at 0.5, 1, 1.5, 3, 6, 8, and 10 hours after self-administration of the prescribed dose of HU. HU in the presence (EOT: Week 17) or absence of IMR-687 (Baselines 1 and 2) are presented. HU concentration data were not sorted with respect to HU dose.
Time frame: Baseline (1 and 2) and Week 17
Change From Baseline In F-Cells
Absolute least squares (LS) mean change from baseline at EOT is presented. Change from baseline in pharmacodynamic (PD) biomarkers was analyzed using mixed models for repeated measures with covariate of treatment, visit, treatment-by-visit interaction, and baseline value.
Time frame: Baseline, EOT (Week 25 for participants without HU and Weeks 17 or 25 for participants with HU)
Study participants were enrolled at 13 sites in 2 countries (United Kingdom and United States).
| Milestone | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) |
|---|---|---|---|---|---|
| Started | 15 | 26 | 22 | 27 | 10 |
| Received at least 1 dose of study drug | 12 | 26 | 20 | 25 | 10 |
| Completed | 10 | 19 | 11 | 21 | 10 |
| Not completed | 5 | 7 | 11 | 6 | 0 |
| Withdrew: Adverse event | 1 | 2 | 3 | 2 | 0 |
| Withdrew: Lost to follow-up | 1 | 0 | 0 | 0 | 0 |
| Withdrew: Noncompliance | 1 | 2 | 3 | 0 | 0 |
| Withdrew: Did not meet inclusion criteria | 1 | 0 | 0 | 0 | 0 |
| Withdrew: Withdrawal by subject | 0 | 3 | 2 | 1 | 0 |
| Withdrew: Physician decision | 0 | 0 | 0 | 2 | 0 |
| Withdrew: Study was terminated by sponsor | 0 | 0 | 0 | 1 | 0 |
| Withdrew: Day 1 assessment not done | 1 | 0 | 0 | 0 | 0 |
| Withdrew: Not dosed | 0 | 0 | 1 | 0 | 0 |
| Withdrew: Missed clinical visit | 0 | 0 | 1 | 0 | 0 |
| Withdrew: Missed doses | 0 | 0 | 1 | 0 | 0 |
An adverse event (AE) was defined as any untoward medical occurrence in a clinical study participant administered a pharmaceutical product and which did not necessarily have to have a causal relationship with this treatment. An SAE was defined as any AE that resulted in 1 or more of the following outcomes: death, required or prolonged hospitalization, life-threatening, persistent or significant disability/incapacity, congenital anomaly or birth defect, or other medically important event. A summary of serious and all other non-serious AEs, regardless of causality, is located in the Reported Adverse Events module.
| Participants | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | All IMR-687 | All Placebo |
|---|---|---|---|---|---|---|---|
| TEAEs | 12 | 24 | 18 | 23 | 10 | 59 | 28 |
| SAEs | 4 | 7 | 8 | 5 | 3 | 16 | 11 |
For PK assessments of participants who did not concomitantly receive HU, serial blood samples for IMR-687 plasma concentrations were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 25) assessments are presented.
| ng/mL | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) |
|---|---|---|
| Day 1: Single Dose | 512 ± 30.1 | 1130 ± 33.5 |
| Week 25: Steady State | 1290 ± 36.4 | 2180 ± 24.1 |
For PK assessments of participants who did not concomitantly receive HU, serial blood samples for IMR-687 plasma concentrations were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 25) assessments are presented.
| h*ng/mL | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) |
|---|---|---|
| Day 1: Single Dose | 2850 ± 12.5 | 6590 ± 17.7 |
| Week 25: Steady State | 8420 ± 24.1 | 15000 ± 22.3 |
For PK assessments of participants who concomitantly received HU, serial blood samples for IMR-687 PK were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 17) assessments are presented.
| ng/mL | IMR-687 50 mg/100 mg (With HU) |
|---|---|
| Day 1: Single Dose | 657 ± 24.7 |
| Week 17: Steady State | 1370 ± 18.6 |
For PK assessments of participants who concomitantly received HU, serial blood samples for IMR-687 plasma concentrations were drawn predose at 0.5, 1, 1.5, 2, 4, 6, and 8 hours after administration of study drug; and at 24 hours after administration of study drug. Day 1 (single-dose) and steady-state (Week 17) assessments are presented.
| h*ng/mL | IMR-687 50 mg/100 mg (With HU) |
|---|---|
| Day 1: Single Dose | 3090 ± 34.0 |
| Week 17: Steady State | 7300 ± 16.1 |
For PK assessments of participants who concomitantly received HU, serial blood samples for HU PK were drawn predose and at 0.5, 1, 1.5, 3, 6, 8, and 10 hours after self-administration of the prescribed dose of HU. HU in the presence (end of treatment \[EOT\]: Week 17) or absence of IMR-687 (Baselines 1 and 2) are presented. HU concentration data were not sorted with respect to HU dose.
| μg/mL | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) |
|---|---|---|
| Baseline 1 | 25.3 ± 36.7 | 20.6 ± 87.8 |
| Baseline 2 | 24.8 ± 38.1 | 25.4 ± 98.6 |
| Week 17 | 24.5 ± 55.2 | 20.5 ± 127 |
For PK assessments of participants who concomitantly received HU, serial blood samples for HU PK were drawn predose and at 0.5, 1, 1.5, 3, 6, 8, and 10 hours after self-administration of the prescribed dose of HU. HU in the presence (EOT: Week 17) or absence of IMR-687 (Baselines 1 and 2) are presented. HU concentration data were not sorted with respect to HU dose.
| h*μg/mL | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) |
|---|---|---|
| Baseline 1 | 99.2 ± 32.4 | 113 ± 87.7 |
| Baseline 2 | 103 ± 30.7 | 129 ± 71.7 |
| Week 17 | 122 ± 23.0 | 91.4 ± 127 |
Absolute least squares (LS) mean change from baseline at EOT is presented. Change from baseline in pharmacodynamic (PD) biomarkers was analyzed using mixed models for repeated measures with covariate of treatment, visit, treatment-by-visit interaction, and baseline value.
| percentage of F-cells | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Pooled IMR-687 (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) |
|---|---|---|---|---|---|---|
| Change From Baseline In F-Cells | 3.97 ± 4.07 | 5.66 ± 2.87 | 4.81 ± 2.48 | -6.00 ± 3.77 | -2.49 ± 6.00 | 7.38 ± 15.54 |
VOCs include the events of acute painful crisis and acute chest symptoms (includes fever, cough, sputum production, shortness of breath, tachypnea, hypoxia, and chest pain).
| Participants | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | All IMR-687 | All Placebo |
|---|---|---|---|---|---|---|---|
| Number Of Participants With Vaso-occlusive Crisis (VOCs) | 6 | 14 | 14 | 10 | 7 | 30 | 21 |
VOCs include the events of acute painful crisis and acute chest symptoms (includes fever, cough, sputum production, shortness of breath, tachypnea, hypoxia, and chest pain). Time to first VOC event was assessed by Kaplan Meier analysis. For this analysis, HU and without HU population groups were pooled for IMR-687 and placebo. In addition, pooled IMR-687 (all doses) are presented.
| days | IMR-687 50 mg/100 mg | IMR-687 100 mg/200 mg | All IMR-687 | All Placebo |
|---|---|---|---|---|
| Time To First VOC Event | NA (60.00 to NA) | 139.00 (35.00 to NA) | 169.00 (80.00 to NA) | 87.00 (26.00 to 167.00) |
Collected over Day 1 (after dosing) through up to Week 24. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| IMR-687 50 mg/100 mg (Without HU) | 0/12 (0%) | 4/12 (33.3%) | 12/12 (100%) |
| IMR-687 100 mg/200 mg (Without HU) | 0/26 (0%) | 7/26 (26.9%) | 22/26 (84.6%) |
| Placebo (Without HU) | 0/20 (0%) | 8/20 (40%) | 16/20 (80%) |
| IMR-687 50 mg/100 mg (With HU) | 0/25 (0%) | 5/25 (20%) | 23/25 (92%) |
| Placebo (With HU) | 0/10 (0%) | 3/10 (30%) | 10/10 (100%) |
| All IMR-687 | 0/63 (0%) | 16/63 (25.4%) | 57/63 (90.5%) |
| All Placebo | 0/30 (0%) | 11/30 (36.7%) | 26/30 (86.7%) |
| Event | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | All IMR-687 | All Placebo |
|---|---|---|---|---|---|---|---|
| Sickle cell anaemia with crisisBlood and lymphatic system disorders | 3/12 | 7/26 | 7/20 | 3/25 | 3/10 | 13/63 | 10/30 |
| Uterine leiomyomaNeoplasms benign, malignant and unspecified (incl cysts and polyps) | 1/8 | 0/17 | 0/12 | 0/15 | 0/9 | 1/40 | 0/21 |
| Hepatic lesionHepatobiliary disorders | 1/12 | 0/26 | 0/20 | 0/25 | 0/10 | 1/63 | 0/30 |
| Ovarian cystReproductive system and breast disorders | 0/8 | 0/17 | 0/12 | 1/15 | 0/9 | 1/40 | 0/21 |
| Rash generaliseSkin and subcutaneous tissue disorders | 0/12 | 0/26 | 1/20 | 0/25 | 0/10 | 0/63 | 1/30 |
| Non-cardiac chest painGeneral disorders | 0/12 | 0/26 | 0/20 | 1/25 | 0/10 | 1/63 | 0/30 |
| Multiple injuriesInjury, poisoning and procedural complications | 0/12 | 0/26 | 0/20 | 1/25 | 0/10 | 1/63 | 0/30 |
| Cerebrovascular accidentNervous system disorders | 0/12 | 0/26 | 0/20 | 1/25 | 0/10 | 1/63 | 0/30 |
| PyrexiaGeneral disorders | 0/12 | 1/26 | 0/20 | 0/25 | 0/10 | 1/63 | 0/30 |
| Event | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | All IMR-687 | All Placebo |
|---|---|---|---|---|---|---|---|
| Sickle cell anaemia with crisisBlood and lymphatic system disorders | 5/12 | 9/26 | 9/20 | 10/25 | 6/10 | 24/63 | 15/30 |
| NauseaGastrointestinal disorders | 2/12 | 8/26 | 0/20 | 4/25 | 5/10 | 14/63 | 5/30 |
| HeadacheNervous system disorders | 2/12 | 8/26 | 4/20 | 12/25 | 4/10 | 22/63 | 8/30 |
| Upper respiratory tract infectionInfections and infestations | 3/12 | 1/26 | 2/20 | 2/25 | 2/10 | 6/63 | 4/30 |
| Back painMusculoskeletal and connective tissue disorders | 0/12 | 6/26 | 2/20 | 1/25 | 2/10 | 7/63 | 4/30 |
| FatigueGeneral disorders | 1/12 | 2/26 | 2/20 | 4/25 | 2/10 | 7/63 | 4/30 |
| JaundiceHepatobiliary disorders | 0/12 | 0/26 | 0/20 | 1/25 | 2/10 | 1/63 | 2/30 |
| Pain in extremityMusculoskeletal and connective tissue disorders | 1/12 | 2/26 | 2/20 | 2/25 | 2/10 | 5/63 | 4/30 |
| Influenza like illnessGeneral disorders | 2/12 | 2/26 | 2/20 | 2/25 | 0/10 | 6/63 | 2/30 |
| PainGeneral disorders | 2/12 | 1/26 | 1/20 | 1/25 | 0/10 | 4/63 | 1/30 |
All participants who had received any amount of study drug.
| Age, Continuous(years) | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | Total |
|---|---|---|---|---|---|---|
| Mean | 34.7 ± 8.7 | 32.0 ± 9.3 | 35.2 ± 8.4 | 32.4 ± 9.1 | 28.8 ± 7.1 | 32.8 ± 8.8 |
| Sex: Female, Male(Participants) | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | Total |
|---|---|---|---|---|---|---|
| Female | 8 | 17 | 12 | 15 | 9 | 61 |
| Male | 4 | 9 | 8 | 10 | 1 | 32 |
| Race/Ethnicity, Customized(Participants) | IMR-687 50 mg/100 mg (Without HU) | IMR-687 100 mg/200 mg (Without HU) | Placebo (Without HU) | IMR-687 50 mg/100 mg (With HU) | Placebo (With HU) | Total |
|---|---|---|---|---|---|---|
| Not Hispanic or Latino | 11 | 23 | 19 | 24 | 9 | 86 |
| Not Reported | 1 | 1 | 0 | 1 | 0 | 3 |
| Unknown Ethnicity | 0 | 2 | 1 | 0 | 1 | 4 |
| Black or African American | 12 | 25 | 19 | 24 | 9 | 89 |
| Other | 0 | 1 | 0 | 0 | 0 | 1 |
| Missing | 0 | 0 | 1 | 1 | 1 | 3 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Undecided
Ran from Jan 2018 to primary completion in Aug 2020, 31 months.
Results were first posted in Apr 2022, 1 year 7 months after primary completion.
Of 34 industry-sponsored phase 2 interventional studies under Anemia, Sickle Cell, half reached primary completion within 28 months of starting (the median), counting those still running; a quarter within 16 and three quarters within 41. This study's 31 months is above that.
Counting every sponsor, half of 92 studies reached it within 46 months; a quarter within 24 and three quarters within 73.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Tovinontrine
Cardurion Pharmaceuticals, Inc.