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Study to Determine the Safety and Tolerability of Sotatercept (ACE-011) in Adults With Beta( β)- Thalassemia.

A Phase 2A, Open-label Dose Finding Study to Determine the Safety and Tolerability of Sotatercept (ACE-011) in Adults With BETA(b)-THALASSEMIA.

Status
Terminated
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01571635
Enrollment
46
Registered
2012-04-05
Start date
2012-10-10
Completion date
2022-05-24
Last updated
2023-06-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Beta Thalassemia Intermedia, Beta Thalassemia Major

Keywords

Beta-Thalassaemia

Brief summary

Dose finding study to determine the safety and tolerability of Sotatercept (ACE-011) in adults with Beta (β)-Thalassemia

Interventions

DRUGSOTATERCEPT (ACE-011)

0.1 mg/kg to 1.5mg/kg Sotatercept will be administered as a subcutaneous injection once every 21 days during the treatment period.

Sponsors

Celgene
Lead SponsorINDUSTRY

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Men and women 18 years of age at the time of signing the informed consent document with a diagnosis of β-thalassemia major (including all subtypes) or β-thalassemia intermedia. * For transfusion dependent subjects: permanent transfusion dependency is defined as requiring packed red blood cells (pRBCs) and iron chelation therapy: * Average transfusion requirement of at least 2 units/30 days of pRBCs (Gale, 2011) confirmed for a minimum of 168 days (six months) immediately preceding enrollment (study Day 1, first Dose); * No transfusion-free period of more than 45 consecutive days during the 168 days immediately preceding enrollment (study Day 1, first Dose); * Prior transfusion hemoglobin levels ≤ 10.5 g/dL. * For non-transfusion dependent subjects: non-transfusion dependency is defined as a transfusion free for a minimum of 168 days immediately preceding enrollment (study Day 1, first Dose), with the exception of ≤ to one episode of transfusion in the period of a minimum of 168 days immediately preceding enrollment (study Day 1, first Dose) (One episode of transfusion is defined as ≤ 4 transfusion units administered, occurred within 42 days \[first transfusion is counted as day 1\] due to concurrent illness \[e.g. infection\], \[Guidelines Clin Management of Thalassaemia, 2008\]). (This inclusion criteria is not valid for France). * Performance status: Eastern Cooperative Oncology Group (ECOG) score of 0 to 1 * No concurrent severe hepatic disease: * Aspartate Aminotransferase (AST) or Alanine Transaminase (ALT) no greater than 3 x upper limit of normal (ULN); * Albumin ≥ 3 g/dL. * Serum creatinine ≤ 1.5 x ULN. * Females of childbearing potential participating in the study are to use highly effective methods of birth control during study participation and for 112 days (approximately five times the mean terminal half-life of sotatercept \[23 days\] based on multiple-dose PK data) following the last dose of sotatercept. FCBP must have a negative serum beta Human Chorionic Gonadotropin (β-HCG) pregnancy test within three days of Sotatercept dosing (Day 1). Subjects must be counseled concerning measures to be used to prevent pregnancy and potential toxicities prior to the first dose of sotatercept. A FCBP is a sexually mature woman who has not undergone a hysterectomy or bilateral oophorectomy or who has not been postmenopausal for at least 24 consecutive months (i.e., who has had menses at some time in the preceding 24 months). * Males must agree to use a latex condom during any sexual contact with FCBSs while participating in the study and for 112 days following the last dose of Sotatercept, even if he has undergone a successful vasectomy. Subjects must be counseled concerning measures to be used to prevent pregnancy and potential toxicities prior to the first dose of sotatercept. * Agreement to adhere to the study visit schedule, understand and comply with all protocol requirements. * Understand and provide written informed consent.

Exclusion criteria

* Any serious medical condition, laboratory abnormality, or psychiatric illness that would prevent the subject from signing participating in the study. * Evidence of active Hepatitis C antibody (HCV), Hepatitis B surface antigen (HBsAg and HB core Ab), or Human Immunodeficiency Virus (HIV) antibody. * Known history of thromboembolic events ≥ Grade 3 according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version 4.0 (current active minor version). * Subjects with insulin dependent diabetes. * Subjects with major cardiac problems such as: * Major risk of heart failure, confirmed with myocardiac T2\* ≤ 10 ms. Myocardiac T2\* performed in the last one and a half years prior to subject enrollment (study Day 1, first Dose) will be considered valid. * Cardiac arrhythmia which requires treatment (i.e. atrial fibrillation). * Treatment with another investigational drug or device \< 28 days prior to study entry. * Use of an Erythropoiesis Stimulating Agent (ESA) within the 28 days prior to enrollment (study Day 1, first Dose). * Subjects on hydroxyurea treatment for which the dose was changed in the last one year prior to subject enrollment (study Day 1, first Dose). * Subjects on anticoagulant therapy, such as warfarin. * Subjects who started bisphosphonates within the last three months prior to subject enrollment (study Day 1, first Dose). * Pregnant or lactating females. * Uncontrolled hypertension. Controlled hypertension for this protocol is considered ≤ Grade 1 according to NCI CTCAE version 4.0 (current active minor version) (Appendix B). * A history of major organ damage including: * Liver disease with ALT \> 3x ULN or histopathological evidence of liver cirrhosis on liver biopsy; * Heart disease with ejection fraction ≥ Grade 2 according to NCI CTCAE version 4.0 (current active minor version); * Kidney disease with a calculated creatinine clearance \< 40 mL/min (Cockcroft-Gault formula); * Pulmonary fibrosis or pulmonary hypertension as confirmed by a specialist. * Adrenal insufficiency. * Heart failure as classified by the New York Heart Association (NYHA) classification of 3 or higher (Appendix C). * Major surgery within 30 days prior to study Day 1 (subjects must have completely recovered from any previous surgery prior to study Day 1). * History of severe allergic or anaphylactic reactions or hypersensitivity to recombinant proteins or excipients in the Investigational Product (see Investigator Brochure).

Design outcomes

Primary

MeasureTime frameDescription
Potential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended DoseFrom first dose up to 28 days post the first doseNumber of participants with dose-limiting toxicities (DLT) are used to determine the potential recommended dose (PRD). PRD is defined as the highest dose with up to 1 out of 6 patients experiencing a DLT. DLT is defined as any side effects of the study treatment serious enough to prevent an increase in dose or level of treatment, including at least one of the following: Hypertension ≥ Grade 3 per National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0; Hgb \> 14 g/dL sustained for four weeks; any NCI CTCAE toxicity ≥ Grade 3. Grade 3 is defined as severe or medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; limiting self-care activities of daily life. PRD was identified as 1 mg/kg. Due to study termination, no patients were enrolled after 1 mg/kg cohort or in the Expansion Cohort. Thus, primary analyses to determine recommended dose (RD) were not conducted.

Secondary

MeasureTime frameDescription
Number of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia ParticipantsMeasurements were taken in 9 and 12-week intervals, from baseline up to approximately 112 monthsThe Number of participants with a change in Hemoglobin levels will be listed for non-RBC transfusion dependent participants. Baseline assessments are the average of the last two measurements prior to the start of therapy.
Number of Participants Experiencing Adverse Events (AEs)From first dose up to 112 days after the last dose of study treatment (up to 115 months)An Adverse Event (AE) is defined as any new untoward medical occurrence or worsening of a pre-existing medical condition in a clinical investigation participant administered study treatment and that does not necessarily have a causal relationship with this treatment. Adverse events are graded on a scale from 1 to 5, with Grade 1 being mild and asymptomatic; Grade 2 is moderate requiring minimal, local or noninvasive intervention; Grade 3 is severe or medically significant but not immediately life-threatening; Grade 4 events are usually severe enough to require hospitalization; Grade 5 events are fatal. Treatment emergent adverse events (TEAE) are defined as an AE that began after the start of trial medication treatment; or if the event was continuous from baseline and was serious, trial medication-related, or resulted in death, discontinuation, or interruption or reduction of trial therapy.
Number of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During TreatmentFrom baseline to the last dose of study treatment (up to approximately 112 months)Transfusion burden at baseline is defined as the total number of units of RBC transfusions that participants received within 168 days (24 weeks) prior to the first dose of study therapy. Transfusion burden during treatment is defined as the total number of RBC transfusion units that each participant received during the treatment divided by the treatment duration and multiplied by 168 days. The result is a 168-day transfusion burden average. Baseline measurement includes RBC transfusion history for transfusion dependent and non-transfusion dependent participants, starting at 168 days prior to enrollment.
Number of Participants With Anti-Drug Antibody (ADA)From first dose up to 4 months after last dose (up to approximately 116 months)The number of participants with Anti-Sotatercept Antibody is a summary of antidrug antibody (ADA) status for ADA-evaluated participants. A participant is counted as 'positive' if there is any positive result captured during the study, a participant is counted as 'negative' if there is no positive result captured during the study. ADA data was collected Day 1 in dose schedules 1 through 6. Starting from Dose 7, ADA was measured at Day 1 every 3 Doses, then finally at the post-treatment follow-up visit at Month 2 and Month 4.
Number of Participants Experiencing Quality of Life (QOL) Change From BaselineFrom pre-dose up to Dose 8 (168 days/6months) and Dose 16 (336 days/12months) onlyThe number of participants in the expansion cohort experiencing changes from baseline in Quality of Life. QOL was planned to be assessed at Day 168 (6 months) and Day 336 (12 months), after Dose 1 Day 1, independent of Dose Delay for participants enrolled in the Expansion Cohort only. QOL was planned to be calculated using the SF-36 and the FACT Anemia. The SF-36 is a Medical Outcomes Study (MOS) consisting of 36 questions developed to determine health status. The SF-36 measures eight scales: physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional, and mental health. The FACT Anemia measures fatigue and other anemia-related symptoms with the Functional Assessment of Cancer Therapy (FACT) Measurement System. Due to early study termination, no participants were enrolled in the expansion cohort and QOL was not assessed.
Concentrations of Sotatercept in SerumDose 1, Day 8; Dose 1, Day 15; Dose 2, Day 1; Dose 2, Day 8; Dose 3, Day 1; Dose 3, Day 8; Dose 4, Day 1; Dose 5, Day 1; Dose 6, Day 1Sotatercept was administered as a subcutaneous injection every 21 days during the Treatment Period. Pharmacokinetic (PK) samples were collected at the pre-specified timepoints.

Countries

France, Greece, Italy, United Kingdom

Participant flow

Pre-assignment details

The Sponsor decided to stop advancing sotatercept development in the β-thalassemia indication; therefore, the study participants enrollment stopped during the Treatment Period. No participants were enrolled in the dose level 1.5 mg/kg that was planned in the protocol. Additionally, the protocol planned to enroll approximately 30 participants in an expansion cohort once the potential recommended dose (PRD) was defined. Due to early termination of the study, the expansion cohort was not opened.

Participants by arm

ArmCount
Dose Level 1a: 0.1 mg/kg
Dose level 1a (starting dose) 0.1 mg/kg Sotatercept will be administered as an SC injection once every 21 days for up to six planned doses during the Treatment Period.
8
Dose Level 1b: 0.3 mg/kg
Dose level 1b (starting dose) 0.3 mg/kg Sotatercept will be administered as an SC injection once every 21 days for up to six planned doses during the Treatment Period.
9
Dose Level 2: 0.5 mg/kg
Dose level 2 (escalation dose) 0.5 mg/kg Sotatercept will be administered as an SC injection once every 21 days for up to six planned doses during the Treatment Period.
8
Dose Level 3: 0.75 mg/kg
Dose level 3 (escalation dose) 0.75 mg/kg Sotatercept will be administered as an SC injection once every 21 days for up to six planned doses during the Treatment Period.
12
Dose Level 4: 1 mg/kg
Dose level 4 (escalation dose) 1 mg/kg Sotatercept will be administered as an SC injection once every 21 days for up to six planned doses during the Treatment Period.
9
Total46

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004
Overall StudyAdverse Event30235
Overall StudyLack of Efficacy02012
Overall StudyOther reasons21221
Overall StudyStudy terminated by sponsor04131
Overall StudyWithdrew consent11230

Baseline characteristics

CharacteristicDose Level 1a: 0.1 mg/kgTotalDose Level 4: 1 mg/kgDose Level 3: 0.75 mg/kgDose Level 2: 0.5 mg/kgDose Level 1b: 0.3 mg/kg
Age, Continuous39.5 Years
STANDARD_DEVIATION 8.21
39.5 Years
STANDARD_DEVIATION 9.22
41.0 Years
STANDARD_DEVIATION 10.36
44.0 Years
STANDARD_DEVIATION 10.29
38.5 Years
STANDARD_DEVIATION 7.63
40.0 Years
STANDARD_DEVIATION 9.89
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
1 Participants4 Participants1 Participants2 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants2 Participants0 Participants0 Participants2 Participants0 Participants
Race (NIH/OMB)
White
7 Participants40 Participants8 Participants10 Participants6 Participants9 Participants
Sex: Female, Male
Female
4 Participants22 Participants3 Participants8 Participants3 Participants4 Participants
Sex: Female, Male
Male
4 Participants24 Participants6 Participants4 Participants5 Participants5 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
deaths
Total, all-cause mortality
0 / 80 / 90 / 80 / 120 / 9
other
Total, other adverse events
8 / 89 / 98 / 812 / 129 / 9
serious
Total, serious adverse events
3 / 83 / 93 / 83 / 123 / 9

Outcome results

Primary

Potential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended Dose

Number of participants with dose-limiting toxicities (DLT) are used to determine the potential recommended dose (PRD). PRD is defined as the highest dose with up to 1 out of 6 patients experiencing a DLT. DLT is defined as any side effects of the study treatment serious enough to prevent an increase in dose or level of treatment, including at least one of the following: Hypertension ≥ Grade 3 per National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0; Hgb \> 14 g/dL sustained for four weeks; any NCI CTCAE toxicity ≥ Grade 3. Grade 3 is defined as severe or medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; limiting self-care activities of daily life. PRD was identified as 1 mg/kg. Due to study termination, no patients were enrolled after 1 mg/kg cohort or in the Expansion Cohort. Thus, primary analyses to determine recommended dose (RD) were not conducted.

Time frame: From first dose up to 28 days post the first dose

Population: All treated participants

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Dose Level 1a: 0.1 mg/kgPotential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended Dose0 Participants
Dose Level 1b: 0.3 mg/kgPotential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended Dose0 Participants
Dose Level 2: 0.5 mg/kgPotential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended Dose0 Participants
Dose Level 3: 0.75 mg/kgPotential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended Dose0 Participants
Dose Level 4: 1 mg/kgPotential Recommended Dose as Determined by Number of Participants Experiencing Dose-Limiting Toxicities and Recommended Dose0 Participants
Secondary

Concentrations of Sotatercept in Serum

Sotatercept was administered as a subcutaneous injection every 21 days during the Treatment Period. Pharmacokinetic (PK) samples were collected at the pre-specified timepoints.

Time frame: Dose 1, Day 8; Dose 1, Day 15; Dose 2, Day 1; Dose 2, Day 8; Dose 3, Day 1; Dose 3, Day 8; Dose 4, Day 1; Dose 5, Day 1; Dose 6, Day 1

Population: All treated participants

ArmMeasureGroupValue (MEDIAN)
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 1325.35 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 6, Day 1297.60 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 15388.7 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 8683.1 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 4, Day 1334.85 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 8758.1 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 8598.3 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 5, Day 1385.1 ng/mL
Dose Level 1a: 0.1 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 1294.75 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 82319.9 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 4, Day 11022.3 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 81454.05 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 151150.1 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 1956.8 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 1770.3 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 6, Day 11368.10 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 5, Day 11473.9 ng/mL
Dose Level 1b: 0.3 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 82065 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 11468.05 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 12157.3 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 6, Day 12266.40 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 4, Day 12441.6 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 152329.75 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 84507.3 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 5, Day 11618.8 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 83045.45 ng/mL
Dose Level 2: 0.5 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 84136.8 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 4, Day 14137.1 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 13628.45 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 85837.65 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 154279.65 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 12955.2 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 88373.05 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 87753.35 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 5, Day 14449.7 ng/mL
Dose Level 3: 0.75 mg/kgConcentrations of Sotatercept in SerumDose 6, Day 14062.80 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 12602.6 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 11701.5 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 152405.6 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 6, Day 12780.80 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 5, Day 13048 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 1, Day 83874 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 3, Day 86050.8 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 2, Day 85148.1 ng/mL
Dose Level 4: 1 mg/kgConcentrations of Sotatercept in SerumDose 4, Day 12869.2 ng/mL
Secondary

Number of Participants Experiencing Adverse Events (AEs)

An Adverse Event (AE) is defined as any new untoward medical occurrence or worsening of a pre-existing medical condition in a clinical investigation participant administered study treatment and that does not necessarily have a causal relationship with this treatment. Adverse events are graded on a scale from 1 to 5, with Grade 1 being mild and asymptomatic; Grade 2 is moderate requiring minimal, local or noninvasive intervention; Grade 3 is severe or medically significant but not immediately life-threatening; Grade 4 events are usually severe enough to require hospitalization; Grade 5 events are fatal. Treatment emergent adverse events (TEAE) are defined as an AE that began after the start of trial medication treatment; or if the event was continuous from baseline and was serious, trial medication-related, or resulted in death, discontinuation, or interruption or reduction of trial therapy.

Time frame: From first dose up to 112 days after the last dose of study treatment (up to 115 months)

Population: All treated participants

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one drug-related grade 2/3/4 TEAE4 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one grade 2/3/4 TEAE7 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE leading to sotatercept withdrawal3 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)TEAE leading to dose interruption2 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious drug- related TEAE2 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious TEAE3 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE8 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)TEAE leading to dose interruption5 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one grade 2/3/4 TEAE9 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE leading to sotatercept withdrawal0 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE9 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious TEAE3 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious drug- related TEAE1 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one drug-related grade 2/3/4 TEAE3 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE8 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)TEAE leading to dose interruption4 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious TEAE3 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one grade 2/3/4 TEAE6 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one drug-related grade 2/3/4 TEAE4 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious drug- related TEAE1 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE leading to sotatercept withdrawal2 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious TEAE3 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one drug-related grade 2/3/4 TEAE7 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)TEAE leading to dose interruption2 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE leading to sotatercept withdrawal3 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious drug- related TEAE0 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE12 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one grade 2/3/4 TEAE11 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)TEAE leading to dose interruption5 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE leading to sotatercept withdrawal5 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious drug- related TEAE1 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one drug-related grade 2/3/4 TEAE7 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one grade 2/3/4 TEAE9 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one TEAE9 Participants
Dose Level 4: 1 mg/kgNumber of Participants Experiencing Adverse Events (AEs)Participants with at least one serious TEAE3 Participants
Secondary

Number of Participants Experiencing Quality of Life (QOL) Change From Baseline

The number of participants in the expansion cohort experiencing changes from baseline in Quality of Life. QOL was planned to be assessed at Day 168 (6 months) and Day 336 (12 months), after Dose 1 Day 1, independent of Dose Delay for participants enrolled in the Expansion Cohort only. QOL was planned to be calculated using the SF-36 and the FACT Anemia. The SF-36 is a Medical Outcomes Study (MOS) consisting of 36 questions developed to determine health status. The SF-36 measures eight scales: physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional, and mental health. The FACT Anemia measures fatigue and other anemia-related symptoms with the Functional Assessment of Cancer Therapy (FACT) Measurement System. Due to early study termination, no participants were enrolled in the expansion cohort and QOL was not assessed.

Time frame: From pre-dose up to Dose 8 (168 days/6months) and Dose 16 (336 days/12months) only

Population: Expansion cohort

Secondary

Number of Participants With Anti-Drug Antibody (ADA)

The number of participants with Anti-Sotatercept Antibody is a summary of antidrug antibody (ADA) status for ADA-evaluated participants. A participant is counted as 'positive' if there is any positive result captured during the study, a participant is counted as 'negative' if there is no positive result captured during the study. ADA data was collected Day 1 in dose schedules 1 through 6. Starting from Dose 7, ADA was measured at Day 1 every 3 Doses, then finally at the post-treatment follow-up visit at Month 2 and Month 4.

Time frame: From first dose up to 4 months after last dose (up to approximately 116 months)

Population: All treated participants

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Dose Level 1a: 0.1 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Negative8 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Positive0 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Negative8 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Positive1 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Negative8 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Positive0 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Positive2 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Negative10 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Negative9 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Anti-Drug Antibody (ADA)Positive0 Participants
Secondary

Number of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants

The Number of participants with a change in Hemoglobin levels will be listed for non-RBC transfusion dependent participants. Baseline assessments are the average of the last two measurements prior to the start of therapy.

Time frame: Measurements were taken in 9 and 12-week intervals, from baseline up to approximately 112 months

Population: Non-RBC transfusion dependent participants-participants who are in the safety population and are not transfusion dependent. This is a subgroup of the B-thalassemia intermedia population.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Dose Level 1a: 0.1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)0 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)0 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)0 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)0 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)5 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)2 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)2 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)4 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)2 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)2 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)4 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)4 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)6 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)6 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)6 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)6 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)1 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants12-Week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)1 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.5 g/dl change from baseline (non-transfusion dependent participants)1 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Hemoglobin Level Increase From Baseline in Non-Transfusion Dependent B-Thalassemia Intermedia Participants9-week episode with Hgb ≥ 1.0 g/dl change from baseline (non-transfusion dependent participants)2 Participants
Secondary

Number of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment

Transfusion burden at baseline is defined as the total number of units of RBC transfusions that participants received within 168 days (24 weeks) prior to the first dose of study therapy. Transfusion burden during treatment is defined as the total number of RBC transfusion units that each participant received during the treatment divided by the treatment duration and multiplied by 168 days. The result is a 168-day transfusion burden average. Baseline measurement includes RBC transfusion history for transfusion dependent and non-transfusion dependent participants, starting at 168 days prior to enrollment.

Time frame: From baseline to the last dose of study treatment (up to approximately 112 months)

Population: Safety Population Transfusion Dependent-All participants who received at least one dose of sotatercept and are transfusion dependent.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
Dose Level 1a: 0.1 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 25% reduction0 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 50% reduction0 Participants
Dose Level 1a: 0.1 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 33% reduction0 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 33% reduction0 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 25% reduction0 Participants
Dose Level 1b: 0.3 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 50% reduction0 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 33% reduction2 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 25% reduction2 Participants
Dose Level 2: 0.5 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 50% reduction1 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 25% reduction4 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 50% reduction2 Participants
Dose Level 3: 0.75 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 33% reduction3 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 33% reduction1 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 25% reduction3 Participants
Dose Level 4: 1 mg/kgNumber of Participants With Red Blood Cell Transfusion Burden Reduction From Baseline During Treatment≥ 50% reduction0 Participants

Source: ClinicalTrials.gov · Data processed: Feb 23, 2026