A Phase 2 interventional study of AG-348 in Thalassemia, sponsored by Agios Pharmaceuticals, Inc.. Active, not recruiting at 4 sites in 3 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-30.
Sponsored by Agios Pharmaceuticals, Inc. · Phase 2, Interventional, and Treatment
Study AG348-C-010 is a multicenter study to evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of treatment with AG-348 in adult participants with non-transfusion-dependent thalassemia (NTDT). This study includes a core period (up to 24 weeks) followed by an extension period (up to 10 years) for eligible participants. 20 participants with NTDT were enrolled. The initial dose of AG-348 was 50 milligrams (mg) twice daily (BID) with one potential dose-level increase to 100 mg BID at the Week 6 visit based on the participant's safety and hemoglobin (Hb) concentrations.
416 studies on the registry are indexed under Thalassemia; 67 are open to participants now.
This study's enrollment of 20 is below the median of 37 across 277 interventional studies indexed under Thalassemia.
Browse Thalassemia studies →Agios Pharmaceuticals, Inc. is the lead sponsor of 52 studies on the registry; 6 are open to participants now.
Of its 23 completed or terminated interventional studies of FDA-regulated products, 4 (17%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Participants with alpha or beta thalassemia received AG-348 50 mg twice daily (BID), orally up to Week 6. Following Week 6, depending on the participants' safety and hemoglobin (Hb) concentrations, they could undergo one potential dose-level increase from 50 to 100 mg BID. After completion of the Core Period of 24 weeks, participants were eligible to continue to receive AG-348 in the Extension Period which is up to 10 years.
Drug: AG-348
AG-348 tablet orally BID
Also known as: Mitapivat
Percentage of Participants Achieving a Hemoglobin Response (HR)
HR was defined as a ≥1.0 gram per deciliter (g/dL) increase in Hb concentration from Baseline at 1 or more assessments between Week 4 and Week 12 (inclusive). A participant's Baseline Hb concentration was defined as the average of all the participant's available Hb concentrations during the screening period up to the first dose of study drug.
Time frame: Up to 12 weeks
Average Change From Baseline in Hb Concentrations From Week 12 to Week 24
A participant's Baseline Hb concentration was defined as the average of all the participant's available Hb concentrations during the screening period up to the first dose of study drug.
Time frame: Baseline, Week 12 to Week 24
Percentage of Participants Achieving a Sustained Hb Response (sHR)
sHR was defined as achieving HR and achieving a ≥1.0 g/deciliter (dL) increase in Hb concentration at 2 or more evaluable Hb assessments out of the 4 scheduled assessments between the Week 12 visit and Week 24 visit.
Time frame: Week 12 to Week 24
Percentage of Participants Achieving a Delayed Hb Response
Delayed Hb response was defined as not achieving HR and achieving a ≥1.0 g/dL increase in Hb concentration at 1 or more Hb assessments after Week 12.
Time frame: Week 12 to Week 24
Change From Baseline in Hb Concentration Over the Duration of the Extension Period
Time frame: Baseline up to approximately 10.5 years
Time to First ≥1.0 g/dL Increase in Hb Concentration
Time frame: Up to Week 24
Change From Baseline in Reticulocyte Count
Time frame: Up to approximately 10.5 years
Change From Baseline in Bilirubin
Time frame: Up to approximately 10.5 years
Change From Baseline in Lactate Dehydrogenase (LDH)
Time frame: Up to approximately 10.5 years
Change From Baseline in Haptoglobin
Time frame: Up to approximately 10.5 years
Change From Baseline in Nucleated Red Blood Cells (NRBCs)
Time frame: Up to approximately 10.5 years
Change From Baseline in Erythropoietin (EPO)
Time frame: Up to approximately 10.5 years
Change From Baseline in Soluble Transferrin Receptor
Time frame: Up to approximately 10.5 years
Drug Concentrations Over Time for AG-348
Time frame: Predose (60 minutes) and 0.00 hour, 0.50 hour, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
AUC0-8h: Area Under the Plasma Concentration-time Curve From Time 0 to 8 Hours of AG-348
Time frame: Predose (60 minutes) and 30 minutes, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
AUC0-t: Area Under the Plasma Concentration-time Curve From Time 0 to Time of the Last Quantifiable Concentration of AG-348
Time frame: Predose (60 minutes) and 30 minutes, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
Cmax: Maximum Observed Plasma Concentration of AG-348
Time frame: Predose (60 minutes) and 30 minutes, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
Tmax: Time to Reach the Maximum Plasma Radioactivity Concentration (Cmax)
Time frame: Predose (60 minutes) and 30 minutes, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
Tlast: Time of the Last Quantifiable Concentration of AG-348
Time frame: Predose (60 minutes) and 30 minutes, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
Ctrough: Observed Plasma Concentration at the End of a Dosing Interval of AG-348
Time frame: Predose (60 minutes) and 30 minutes, 1 hour, 2 hours, 4 hours, and 8 hours postdose on Day 1 and Week 12
Percentage of Participants With Treatment-Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs), AEs of Special Interest (AESIs), and TEAEs Leading to Study Drug Dose Reduction, Study Drug Interruption, and Study Drug Discontinuation
An AE is any unfavorable and unintended sign, symptom, or disease, whether or not related to the investigational product. A TEAE was defined as any AE with onset post study drug treatment. An SAE was defined as any untoward medical occurrence that results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or is medically important. AESIs are predefined AEs that required close monitoring and prompt reporting to the sponsor. AESIs included protocol-specified transaminase increase.
Time frame: From signing the inform consent form up to data cut-off date: 20 August 2020 (Up to approximately 19 months)
Participants took part in the study at 4 investigative sites in the United States, Canada, and United Kingdom from 28 December 2018 to 30 September 2030. Results are reported for the primary and secondary outcome measures for the 24-week Core Period (data cut-off date: 20 August 2020). The Extension Period of this study is ongoing.
| Milestone | AG-348 |
|---|---|
| Started | 20 |
| Completed | 19 |
| Not completed | 1 |
| Withdrew: Adverse event | 1 |
| Milestone | AG-348 |
|---|---|
| Started | 19 |
| Completed | 0 |
| Not completed | 19 |
| Withdrew: Withdrawal of consent | 1 |
| Withdrew: Physician decision | 1 |
| Withdrew: Ongoing | 17 |
HR was defined as a ≥1.0 gram per deciliter (g/dL) increase in Hb concentration from Baseline at 1 or more assessments between Week 4 and Week 12 (inclusive). A participant's Baseline Hb concentration was defined as the average of all the participant's available Hb concentrations during the screening period up to the first dose of study drug.
| percentage of participants | AG-348 |
|---|---|
| Percentage of Participants Achieving a Hemoglobin Response (HR) | 80.0 (59.90 to 92.86) |
A participant's Baseline Hb concentration was defined as the average of all the participant's available Hb concentrations during the screening period up to the first dose of study drug.
| grams per liter (g/L) | AG-348 |
|---|---|
| Baseline | 79.44 ± 13.690 |
| Average Change from Baseline: Week 12 to 24 | 13.01 ± 6.283 |
sHR was defined as achieving HR and achieving a ≥1.0 g/deciliter (dL) increase in Hb concentration at 2 or more evaluable Hb assessments out of the 4 scheduled assessments between the Week 12 visit and Week 24 visit.
| percentage of participants | AG-348 |
|---|---|
| Percentage of Participants Achieving a Sustained Hb Response (sHR) | 65.0 (44.20 to 82.27) |
Delayed Hb response was defined as not achieving HR and achieving a ≥1.0 g/dL increase in Hb concentration at 1 or more Hb assessments after Week 12.
| percentage of participants | AG-348 |
|---|---|
| Percentage of Participants Achieving a Delayed Hb Response | 10.0 (1.81 to 28.26) |
Results for this outcome have not been posted.
| weeks | AG-348 |
|---|---|
| Time to First ≥1.0 g/dL Increase in Hb Concentration | 4.54 ± 3.204 |
Results for this outcome have not been posted.
Results for this outcome have not been posted.
Results for this outcome have not been posted.
Results for this outcome have not been posted.
Results for this outcome have not been posted.
Results for this outcome have not been posted.
Results for this outcome have not been posted.
| nanograms per milliliter (ng/mL) | AG-348 |
|---|---|
| AG-348 50 mg: 0.00 Hour, Day 1 | NA ± NA |
| AG-348 50 mg: 0.50 Hour, Day 1 | NA ± NA |
| AG-348 50 mg: 1 Hour, Day 1 | 785.2 ± 64.6 |
| AG-348 50 mg: 2 Hour, Day 1 | 694.5 ± 26.6 |
| AG-348 50 mg: 4 Hour, Day 1 | 369.2 ± 29.4 |
| AG-348 50 mg: 8 Hour, Day 1 | 128.9 ± 55.1 |
| AG-348 100 mg: 0.00 Hour, Week 12 | 39.39 ± 117.1 |
| AG-348 100 mg: 0.50 Hour, Week 12 | 1030 ± 137.7 |
| AG-348 100 mg: 1 Hour, Week 12 | 1442 ± 30.6 |
| AG-348 100 mg: 2 Hour, Week 12 | 740.1 ± 76.3 |
| AG-348 100 mg: 4 Hour, Week 12 | 302.8 ± 75.2 |
| AG-348 100 mg: 8 Hour, Week 12 | 77.35 ± 48.2 |
| nanograms*hour per milliliter (ng*h/mL) | AG-348 |
|---|---|
| AG-348 50 mg: Day 1 | 3083.3 ± 25.6 |
| AG-348 100 mg: Week 12 | 3384.4 ± 65.7 |
| ng*h/mL | AG-348 |
|---|---|
| AG-348 50 mg: Day 1 | 3083.5 ± 25.6 |
| AG-348 100 mg: Week 12 | 3384.4 ± 65.7 |
| ng/mL | AG-348 |
|---|---|
| AG-348 50 mg: Day 1 | 968.9 ± 38.1 |
| AG-348 100 mg: Week 12 | 1476 ± 93.5 |
| hours | AG-348 |
|---|---|
| AG-348 50 mg: Day 1 | 1.07 (0.48 to 4.07) |
| AG-348 100 mg: Week 12 | 0.53 (0.43 to 2.03) |
| hours | AG-348 |
|---|---|
| AG-348 50 mg: Day 1 | 7.60 (7.50 to 8.02) |
| AG-348 100 mg: Week 12 | 7.55 (7.50 to 7.95) |
| ng/mL | AG-348 |
|---|---|
| AG-348 100 mg: Week 12 | 37.34 ± 117.7 |
An AE is any unfavorable and unintended sign, symptom, or disease, whether or not related to the investigational product. A TEAE was defined as any AE with onset post study drug treatment. An SAE was defined as any untoward medical occurrence that results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or is medically important. AESIs are predefined AEs that required close monitoring and prompt reporting to the sponsor. AESIs included protocol-specified transaminase increase.
| percentage of participants | AG-348 |
|---|---|
| TEAEs | 85.0 |
| SAEs | 5.0 |
| AESIs | 5.0 |
| TEAEs Leading to Study Drug Dose Reduction | 15.0 |
| TEAEs Leading to Study Drug Interruption | 5.0 |
| TEAEs Leading to Study Drug Discontinuation | 5.0 |
Collected over Up to completion of the Core Period data cut-off date: 20 August 2020 (Up to approximately 19 months). Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| AG-348 | 0/20 (0%) | 1/20 (5%) | 17/20 (85%) |
| Event | AG-348 |
|---|---|
| Renal impairmentRenal and urinary disorders | 1/20 |
| Event | AG-348 |
|---|---|
| Initial insomniaPsychiatric disorders | 10/20 |
| DizzinessNervous system disorders | 6/20 |
| HeadacheNervous system disorders | 5/20 |
| DyspepsiaGastrointestinal disorders | 4/20 |
| FatigueGeneral disorders | 4/20 |
| Upper respiratory tract infectionInfections and infestations | 4/20 |
| CoughRespiratory, thoracic and mediastinal disorders | 4/20 |
| Nasal congestionRespiratory, thoracic and mediastinal disorders | 4/20 |
| Abdominal painGastrointestinal disorders | 3/20 |
| DiarrhoeaGastrointestinal disorders | 3/20 |
Full Analysis Set (FAS) included all participants who received at least 1 dose of study treatment.
| Age, Continuous(years) | AG-348 |
|---|---|
| Mean | 45.3 ± 11.81 |
| Sex: Female, Male(Participants) | AG-348 |
|---|---|
| Female | 15 |
| Male | 5 |
| Ethnicity (NIH/OMB)(Participants) | AG-348 |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 19 |
| Unknown or Not Reported | 1 |
| Race (NIH/OMB)(Participants) | AG-348 |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 10 |
| Native Hawaiian or Other Pacific Islander | 1 |
| Black or African American | 1 |
| White | 4 |
| More than one race | 0 |
| Unknown or Not Reported | 4 |
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Plan to share: No
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Agios Pharmaceuticals, Inc.