Trial · NCT04770779
A Study Evaluating the Efficacy and Safety of Mitapivat in Participants With Transfusion-Dependent Alpha- or Beta-Thalassemia (α- or β-TDT)
NCT04770779, Phase 3, Active not recruiting, Agios Pharmaceuticals, Inc.; results first posted 2025-05-25
3 sourcestrials-2026-11-12-0.5.0
Download JSON
Cite this record
ConductScience Library. A Study Evaluating the Efficacy and Safety of Mitapivat in Participants With Transfusion-Dependent Alpha- or Beta-Thalassemia (α- or β-TDT). Trials, record NCT04770779. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT04770779
On this page
Trial
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
- Title
- A Study Evaluating the Efficacy and Safety of Mitapivat in Participants With Transfusion-Dependent Alpha- or Beta-Thalassemia (α- or β-TDT)
- NCT number
- NCT04770779
- Status
- Active not recruiting
- Phases
- Phase 3
- Enrollment
- 258 participants, actual
- Lead sponsor
- Agios Pharmaceuticals, Inc.
- Conditions
- Transfusion-dependent Alpha-Thalassemia, Transfusion-dependent Beta-Thalassemia
- Interventions
- Placebo Matching Mitapivat, Mitapivat
- First posted
- 2021-02-25
- Last updated
- 2026-10-28
- Other registries' IDs
- eudract:2021-000212-34
- Results first posted
- 2025-05-25
Source ClinicalTrials.gov
Registered outcomes20
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description |
|---|---|---|---|
| Primary | Double-blind Period: Percentage of Participants Who Achieved Transfusion Reduction Response (TRR) | Double-blind Period: Baseline through Week 48 | TRR is defined as ≥50% reduction in transfused red blood cells (RBC) units with a reduction of ≥2 units of transfused RBCs in any consecutive 12-week period through Week 48 compared with baseline transfusion burden standardized to 12 weeks. Baseline transfusion burden standardized to 12 weeks= (12/24) × total number of RBC units transfused during 24-week period before the randomization date for participants randomized and not dosed or the start of study treatment for participants randomized and dosed. Participants withdrawn from the study before Week 12 (Day 85) were considered nonresponders. |
| Secondary | Double-blind Period: Percentage of Participants Who Achieved TRR2 | Double-blind period: Baseline through Week 48 | TRR2, defined as a ≥50% reduction in transfused RBC units in any consecutive 24-week period through Week 48 compared with the 24-week baseline transfusion burden, is reported. Baseline transfusion burden standardized to 24 weeks is the total number of RBC units transfused during the 24-week period before the randomization date for participants randomized and not dosed or the start of study treatment for participants randomized and dosed. Participants withdrawn from the study before Week 24 (Day 169) were considered nonresponders. |
| Secondary | Double-blind Period: Percentage of Participants Who Achieved TRR3 | Double-blind period: Baseline up to Week 13 through Week 48 | TRR3, defined as a ≥33% reduction in transfused RBC units from Week 13 through Week 48 compared with the baseline transfusion burden standardized to 36 weeks, is reported. Baseline transfusion burden standardized to 36 weeks= (36/24) × total number of RBC units transfused during the 24-week period before the randomization date for participants randomized and not dosed or the start of study treatment for participants randomized and dosed. Participants withdrawn from the study before Week 48 were considered nonresponders. |
| Secondary | Double-blind Period: Percentage of Participants Who Achieved TRR4 | Double-blind period: Baseline up to Week 13 through Week 48 | TRR4, defined as a ≥50% reduction in transfused RBC units from Week 13 through Week 48 compared with the baseline transfusion burden standardized to 36 weeks, is reported. Baseline transfusion burden standardized to 36 weeks = (36/24) × total number of RBC units transfused during the 24-week period before the randomization date for participants randomized and not dosed or the start of study treatment for participants randomized and dosed. Participants withdrawn from the study before Week 48 were considered nonresponders. |
| Secondary | Double-blind Period: Percent Change From Baseline in Transfused RBC Units | Double-blind Period: Baseline, Week 13 through Week 48 | Transfusion burden from Week 13 through Week 48 standardized to 36 weeks is defined as number of transfused RBC units from Day 85 through Week 48 in the Double-blind Period ×36/(Number of days from Day 85 through Week 48 in the Double-blind Period/7). Baseline transfusion burden standardized to 36 weeks= (36/24)× is the total number of RBC units transfused during the 24-week period before the randomization date for participants randomized and not dosed or within 168 days before the start of study treatment for participants randomized and dosed. |
| Secondary | Double-blind Period: Percentage of Participants Who Achieved Transfusion-Independence | Double-blind Period: Baseline through Week 48 | Transfusion-independence is defined as transfusion-free for ≥8 consecutive weeks through Week 48 in the double-blind period. |
| Secondary | Double-blind Period: Change From Baseline in Iron Levels | Double-blind Period: Baseline through Week 48 | Iron metabolism was assessed based on Iron levels. |
| Secondary | Double-blind Period: Change From Baseline in Serum Ferritin Levels | Double-blind Period: Baseline through Week 48 | Iron metabolism was assessed based on serum ferritin levels. |
| Secondary | Double-blind Period: Change From Baseline in Total Iron Binding Capacity | Double-blind Period: Baseline through Week 48 | Iron metabolism was assessed based on total iron binding capacity. |
| Secondary | Double-blind Period: Change From Baseline in Transferrin Saturation (TSAT) Levels | Double-blind Period: Baseline through Week 48 | Iron metabolism was assessed based on TSAT levels. Transferrin saturation is reported by dividing value of serum iron by total iron binding capacity. |
1 to 10 of 20Source ClinicalTrials.gov
See all 20 registered outcomesOutcomes20
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
| Type | Outcome | Time frame | Population | Units | Measured as |
|---|---|---|---|---|---|
| PRIMARY | Double-blind Period: Percentage of Participants Who Achieved Transfusion Reduction Response (TRR) | Double-blind Period: Baseline through Week 48 | FAS included all participants who were randomized. | percentage of participants | NUMBER |
| SECONDARY | Double-blind Period: Percentage of Participants Who Achieved TRR2 | Double-blind period: Baseline through Week 48 | FAS included all participants who were randomized. | percentage of participants | NUMBER |
| SECONDARY | Double-blind Period: Percentage of Participants Who Achieved TRR3 | Double-blind period: Baseline up to Week 13 through Week 48 | FAS included all participants who were randomized. | percentage of participants | NUMBER |
| SECONDARY | Double-blind Period: Percentage of Participants Who Achieved TRR4 | Double-blind period: Baseline up to Week 13 through Week 48 | FAS included all participants who were randomized. | percentage of participants | NUMBER |
| SECONDARY | Double-blind Period: Percent Change From Baseline in Transfused RBC Units | Double-blind Period: Baseline, Week 13 through Week 48 | FAS included all participants who were randomized. Overall number of participants analyzed indicates number of participants who were evaluable for this outcome measure. | percent change | LEAST_SQUARES_MEAN |
| SECONDARY | Double-blind Period: Percentage of Participants Who Achieved Transfusion-Independence | Double-blind Period: Baseline through Week 48 | FAS included all participants who were randomized. | percentage of participants | NUMBER |
| SECONDARY | Double-blind Period: Change From Baseline in Iron Levels | Double-blind Period: Baseline through Week 48 | FAS included all participants who were randomized. Overall number of participants analyzed indicates number of participants who were evaluable for this outcome measure. | micromoles per liter (µmol/L) | LEAST_SQUARES_MEAN |
| SECONDARY | Double-blind Period: Change From Baseline in Serum Ferritin Levels | Double-blind Period: Baseline through Week 48 | FAS included all participants who were randomized. Overall number of participants analyzed indicates number of participants who were evaluable for this outcome measure. | micrograms per liter (µg/L) | LEAST_SQUARES_MEAN |
| SECONDARY | Double-blind Period: Change From Baseline in Total Iron Binding Capacity | Double-blind Period: Baseline through Week 48 | FAS included all participants who were randomized. Overall number of participants analyzed indicates number of participants who were evaluable for this outcome measure. | µmol/L | LEAST_SQUARES_MEAN |
| SECONDARY | Double-blind Period: Change From Baseline in Transferrin Saturation (TSAT) Levels | Double-blind Period: Baseline through Week 48 | FAS included all participants who were randomized. Overall number of participants analyzed indicates number of participants who were evaluable for this outcome measure. | Ratio | LEAST_SQUARES_MEAN |
1 to 10 of 20Source ClinicalTrials.gov
See all 20 outcomesResults by group77
Each measurement the trial posted, group by group, in the words and numbers it posted.
| Outcome | Group | Category | Value | Spread | Units |
|---|---|---|---|---|---|
| Double-blind Period: Percentage of Participants Who Achieved Transfusion Reduction Response (TRR) | Mitapivat | 30.4 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved Transfusion Reduction Response (TRR) | Placebo | 12.6 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved TRR2 | Mitapivat | 13.5 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved TRR2 | Placebo | 2.3 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved TRR3 | Mitapivat | 14.6 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved TRR3 | Placebo | 1.1 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved TRR4 | Mitapivat | 7.6 | percentage of participants | ||
| Double-blind Period: Percentage of Participants Who Achieved TRR4 | Placebo | 1.1 | percentage of participants | ||
| Double-blind Period: Percent Change From Baseline in Transfused RBC Units | Mitapivat | 10.96 | Standard Error 2.149 | percent change | |
| Double-blind Period: Percent Change From Baseline in Transfused RBC Units | Placebo | 3.32 | Standard Error 2.846 | percent change |
1 to 10 of 77Source ClinicalTrials.gov
See all 77 results by groupParticipant flow8
How many started, completed or left each group, period by period.
| Period | Milestone | Group | Participants | Units counted |
|---|---|---|---|---|
| Overall Study | STARTED | Mitapivat | 171 | |
| Overall Study | STARTED | Placebo | 87 | |
| Overall Study | Safety Analysis Set | Mitapivat | 172 | |
| Overall Study | Safety Analysis Set | Placebo | 85 | |
| Overall Study | COMPLETED | Mitapivat | 155 | |
| Overall Study | COMPLETED | Placebo | 83 | |
| Overall Study | NOT COMPLETED | Mitapivat | 16 | |
| Overall Study | NOT COMPLETED | Placebo | 4 |
Source ClinicalTrials.gov
Adverse events102
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
| Type | Event | Organ system | Group | Affected | At risk | Events |
|---|---|---|---|---|---|---|
| other | Upper respiratory tract infection | Infections and infestations | Mitapivat | 27 | 172 | |
| other | Upper respiratory tract infection | Infections and infestations | Placebo | 14 | 85 | |
| other | Influenza | Infections and infestations | Mitapivat | 14 | 172 | |
| other | Influenza | Infections and infestations | Placebo | 4 | 85 | |
| other | Nasopharyngitis | Infections and infestations | Mitapivat | 11 | 172 | |
| other | Nasopharyngitis | Infections and infestations | Placebo | 4 | 85 | |
| other | Urinary tract infection | Infections and infestations | Mitapivat | 11 | 172 | |
| other | Urinary tract infection | Infections and infestations | Placebo | 0 | 85 | |
| other | COVID-19 | Infections and infestations | Mitapivat | 8 | 172 | |
| other | COVID-19 | Infections and infestations | Placebo | 8 | 85 |
1 to 10 of 102Source ClinicalTrials.gov
See all 102 adverse eventsAdverse event totals6
The totals the trial posted for each group.
| Total | Group | Affected | At risk |
|---|---|---|---|
| Total, all-cause mortality | Mitapivat | 0 | 171 |
| Total, all-cause mortality | Placebo | 0 | 87 |
| Total, other adverse events | Mitapivat | 122 | 172 |
| Total, other adverse events | Placebo | 50 | 85 |
| Total, serious adverse events | Mitapivat | 19 | 172 |
| Total, serious adverse events | Placebo | 13 | 85 |
Source ClinicalTrials.gov
Papers1
The papers the trial lists on ClinicalTrials.gov.
| PMID | Listed as |
|---|---|
| 42721980 | DERIVED |
Source PubMed
Grants0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
None in this release.
Trial comparisons2
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
| Comparison | Source |
|---|---|
| Mitapivat vs Placebo: deaths from any cause | Trial comparisons |
| Mitapivat vs Placebo: serious adverse events | Trial comparisons |
Tests0
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
None in this release.
Data dates
The day each source was copied for this release.
Sources 3
- ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
- ClinicalTrials.govNo license stated
- NIH RePORTER's clinical studies and project filesPublic domain
Each source's terms
- ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
- ClinicalTrials.govnone stated
- NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)
ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
For software
Read this trial from software.
The record and each of its lists are JSON, twenty rows a page. No key.
GET https://conductscience.org/api/trials/v1/NCT04770779
GET https://conductscience.org/api/trials/v1/NCT04770779/results?page=2