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An Efficacy and Safety Study of Luspatercept (ACE-536) for the Treatment of Anemia Due to IPSS-R Very Low, Low or Intermediate Risk Myelodysplastic Syndromes (MDS) in Japanese Subjects Who Are Not Requiring Red Blood Cell Transfusion

A Phase 2, Multicenter, Single-arm Study to Evaluate the Efficacy, Pharmacokinetics, and Safety of Luspatercept (ACE-536) for the Treatment of Anemia Due to IPSS-R Very Low, Low or Intermediate Risk Myelodysplastic Syndromes (MDS) in Japanese Subjects Who Are Not Requiring Red Blood Cell Transfusion

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03900715
Enrollment
21
Registered
2019-04-03
Start date
2019-05-20
Completion date
2023-03-01
Last updated
2024-10-17

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

Conditions

Myelodysplastic Syndromes

Keywords

Myelodysplastic Syndromes, MDS, ACE-536, Anemia

Brief summary

The study will be conducted in compliance with the International Council for Harmonisation (ICH) of Technical Requirements for Registration of Pharmaceuticals for Human Use/Good Clinical Practice (GCP) and applicable regulatory requirements. This is a Phase 2, multicenter, single-arm study to evaluate the efficacy, safety and Pharmacokinetics (PK) of luspatercept (ACE-536) for the treatment of anemia due to International prognostic scoring system-Revised (IPSS-R) very low, low or intermediate risk Myelodysplastic syndromes (MDS)in Japanese subjects who are not requiring Red blood cell (RBC) transfusion. The study is divided into the Screening Period, a Treatment Period and a Post-Treatment Follow up Period.

Detailed description

Anemia is considered to be one of the most prevalent cytopenias in patients who have myelodysplastic syndromes, an umbrella term used to describe disorders relating to the ineffective production of red blood cells, white blood cells, and/or platelets. Ranging in severity from mild (asymptomatic) to severe, anemia can result in patients requiring regular red blood cell (RBC) transfusions, which can lead to further complications from iron overload. The goal of this study is to assess the efficacy, safety and PK of luspatercept in anemic patients who are categorized as International Prognostic Scoring System-Revised (IPSS-R) very low, low, or intermediate risk Myelodysplastic syndrome (MDS), and not requiring RBC transfusion. Subjects deemed eligible for the study will be enrolled and treated with luspatercept. Best supportive care (BSC) may be used in combination with study treatment when clinically indicated per investigator. Best supportive care includes, but is not limited to, treatment with transfusions, antibiotic, antiviral and/or antifungal therapy, and nutritional support as needed. Best supportive care for this study excludes the use of ESAs. Patients should receive treatment up to a minimum of 24 weeks after which an MDS Disease assessment visit is scheduled to assess the response to treatment. Patients who are determined to be experiencing clinical benefit may continue treatment. Continued clinical benefit will be re-assessed every 24 weeks. Once patients are discontinued from study treatment, they will enter a post treatment follow-up period.

Interventions

DRUGLuspatercept

Luspatercept

Sponsors

Celgene
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

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

Inclusion criteria

Subjects must satisfy the following criteria to be enrolled in the study: 1. Subject is ≥ 20 years of age the time of signing the informed consent form (ICF) 2. Subject must understand and voluntarily sign an ICF prior to any study-related assessments/procedures being conducted. 3. Subject is willing and able to adhere to the study visit schedule and other protocol requirements. 4. Subject has a documented diagnosis of MDS according to WHO 2016 classification that meets IPSS-R classification of very low, low, or intermediate risk disease, and: • \< 5% blasts in bone marrow 5. Subject has symptomatic anemia with mean Hgb concentration \< 10.0 g/dL from 2 measurements (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1) that does not require RBC transfusion. If more than one measurement exists in the period of 7 to 35 days prior to W1D1, the most recent value will be used. 6. Subject must be TI, as documented by the following criteria: • No RBC transfusion administered within 16 weeks prior to W1D1 (except transfusions due to blood loss or infection that occurred between 16 and 8 weeks prior to W1D1) 7. Subject has Eastern Cooperative Oncology Group (ECOG) score of 0, 1, or 2 8. Females of childbearing potential (FCBP), defined as a sexually mature woman who: 1\) has achieved menarche at some point, 2) not undergone a hysterectomy or bilateral oophorectomy, or 3) has not been naturally postmenopausal (amenorrhea following cancer therapy or amenorrhea due to other medical reasons does not rule out childbearing potential) for at least 24 consecutive months (ie, has had menses at any time in the preceding 24 consecutive months), must: * Have two negative pregnancy tests as verified by the investigator prior to starting study therapy (unless the screening pregnancy test was done within 72 hours of W1D1). She must agree to ongoing pregnancy testing during the course of the study, and after end of study treatment. This applies even if the subject practices true abstinence1 from heterosexual contact. * Either commit to true abstinence from heterosexual contact (which must be reviewed on a monthly basis and source documented) or agree to use, and be able to comply with, highly effective contraception without interruption, 5 weeks prior to starting investigational product, during the study therapy (including dose interruptions), and for 12 weeks after discontinuation of study therapy. * If breastfeeding, agree to stop breastfeeding prior to the participation in the study and not to resume breastfeeding after treatment discontinuation. 9\. Male subjects must: * Practice true abstinence2 (which must be reviewed prior to each IP administration or on a monthly basis \[eg, in the event of dose delays\]) or agree to use a condom (latex or non-latex, but not made out of natural \[animal\] membrane) during sexual contact with a pregnant female or a female of childbearing potential while participating in the study, during dose interruptions and for at least 12 weeks following investigational product discontinuation, even if he has undergone a successful vasectomy.

Exclusion criteria

The presence of any of the following will exclude a subject from enrollment: 1. Subject with the any of the following prior treatments for underlying disease: * Disease modifying agents (eg, immune-modulatory drug \[IMiDs such as lenalidomide\]) \- Except if the subject received ≤ 1 week of treatment with a disease modifying agent ≥ 8 weeks from W1D1, at the investigator's discretion. * Hypomethylating agents \- Subjects may be enrolled at the investigator's discretion contingent that the subject received no more than 2 injections of HMA. The last dose must be ≥ 8 weeks from the date of W1D1. * Luspatercept (ACE-536) or sotatercept (ACE-011) * Allogeneic and/or autologous hematopoietic cell transplant 2. Subject with myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN) according to WHO 2016 classification (ie, chronic myelomonocytic leukemia (CMML), atypical chronic myeloid leukemia (aCML), BCR-ABL12, juvenile myelomonocytic leukemia (JMML), MDS/MPN unclassifiable. 3. Subject with secondary MDS, ie, MDS that is known to have arisen as the result of chemical injury or treatment with chemotherapy and/or radiation for other diseases. 4. Subject with known clinically significant anemia due to iron, vitamin B12, or folate deficiencies, or autoimmune or hereditary hemolytic anemia, or hypothyroidism, or any type of known clinically significant bleeding or sequestration. Subject with drug induced anemia (eg, mycophenolate). • Iron deficiency to be determined by serum ferritin \< 100 μg/L and additional testing if clinically indicated (eg, calculated transferrin saturation \[iron/total iron binding capacity ≤ 20%\] or bone marrow aspirate stain for iron). 5. Subject with known history of diagnosis of AML 6. Subject receiving any of the following treatment within 8 weeks prior to W1D1: * Anticancer cytotoxic chemotherapeutic agent or treatment * ESAs * Granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colonystimulating factor (GM-CSF), unless given for treatment of febrile neutropenia * Immunosuppressive therapy for MDS * Systemic corticosteroid, except for subjects on a stable or decreasing dose for ≥ 1 week prior to W1D1 for medical conditions other than MDS * Other RBC hematopoietic growth factors (eg, Interleukin-3) * Androgens, unless to treat hypogonadism * Hydroxyurea, anagrelide * Oral retinoids * Arsenic trioxide * Interferon and interleukins * Investigational drug or device, or approved therapy for investigational use (if 5 times the half-life of the previous investigational drug exceeds 8 weeks, then the time of exclusion should be extended up to 5 times the half-life of the investigational drug) 7. Subject with uncontrolled hypertension, defined as repeated elevations of systolic blood pressure (SBP) of ≥ 150 mmHg and/or diastolic blood pressure (DBP) ≥ 100 mmHg despite adequate treatment, or with a history of hypertensive crisis or hypertensive encephalopathy. 8. Subject with any of the following laboratory abnormalities: * Absolute neutrophil count (ANC) \< 500/μL (0.5 x 10\^9/L) * Platelet count \< 30,000/μL (30 x 10\^9/L) (Exclude subjects that may be at risk of bleeding regardless of platelet counts. This includes \[but is not limited to\] subjects currently using aspirin or heparin, immediately after surgery, or easily causes bleeding such as nasal bleeding or subcutaneous bleeding or previous episode of major bleeding where the cause was not effectively treated.) * Estimated glomerular filtration rate (eGFR) \< 40 mL/min/1.73 m\^2 (via the 4-variable modification of diet in renal disease \[MDRD\] formula, Appendix G) * Serum aspartate aminotransferase/serum glutamic oxaloacetic transaminase (AST/SGOT) or alanine aminotransferase/serum glutamic pyruvic transaminase (ALT/SGPT) ≥ 3.0 x upper limit of normal (ULN) * Total bilirubin ≥ 2.0 x ULN. - Higher levels are acceptable if these can be attributed to active red blood cell precursor destruction within the bone marrow (ie, ineffective erythropoiesis) or in the presence of known history of Gilbert Syndrome. 9. Subject with prior history of malignancies, other than MDS, unless the subject has been free of the disease for ≥ 5 years. However, subjects with the following history/concurrent conditions are allowed if considered as curatively treated: * Basal or squamous cell carcinoma of the skin * Carcinoma in situ of the cervix * Carcinoma in situ of the breast * Incidental histologic finding of prostate cancer (T1a or T1b using the tumor, nodes, metastasis \[TNM\] clinical staging system) 10. Subject with major surgery within 8 weeks prior to W1D1. Subjects must have completely recovered from any previous surgery prior to W1D1 11. Subject with history of cerebrovascular accident (including ischemic, embolic, and hemorrhagic cerebrovascular accident), transient ischemic attack, deep venous thrombosis (DVT; including proximal and distal), pulmonary or arterial embolism, arterial thrombosis or other venous thrombosis within 6 months prior to W1D1 Note: prior superficial thrombophlebitis is not an exclusion criterion. 12. Subject with the following cardiac conditions within 6 months prior to W1D1: myocardial infarction, uncontrolled angina, acute decompensated cardiac failure or New York Heart Association (NYHA) Class III-IV heart failure, or uncontrolled cardiac arrhythmia as determined by the investigator. Subjects with a known ejection fraction ˂35%, confirmed by a local echocardiogram (ECHO) or multi-gated acquisition (MUGA) scan performed within 6 months prior to W1D1. 13. Subject with uncontrolled systemic fungal, bacterial, or viral infection (defined as ongoing signs/symptoms related to the infection without improvement despite appropriate antibiotics, antiviral therapy, and/or other treatment). 14. Subject with known human immunodeficiency virus (HIV), known evidence of active infectious hepatitis B, and/or known evidence of active Hepatitis C. Local laboratory testing confirming HIV, hepatitis B, and hepatitis C status should not have been performed beyond 4 weeks prior to the date of ICF signature. 15. Subject with history of severe allergic or anaphylactic reactions or hypersensitivity to recombinant proteins or excipients in luspatercept (see current IB). 16. Pregnant or breastfeeding females. 17. Subject has any significant medical condition, laboratory abnormality, psychiatric illness, or is considered vulnerable by local regulations (eg, imprisoned or institutionalized) that would prevent the subject from participating in the study. 18. Subject has any condition including the presence of laboratory abnormalities, which places the subject at unacceptable risk if he/she were to participate in the study. 19. Subject has any condition or receives concomitant medication that confounds the ability to interpret data from the study. 20. Subject has history of active SARS-CoV-2 infection within 4 weeks prior to screening, unless the subject has adequately recovered from COVID-19 symptoms and related complications as per investigator's discretion and following a discussion with the Medical Monitor. Use of a live COVID-19 vaccine is prohibited within 4 weeks prior to W1D1.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants Who Achieved Hematologic Improvement in Erythroid Response (HI-E) Per International Working Group (IWG) Through Week 24Week 1 Day 1 through Week 24Hematologic improvement is defined as the percent of participants meeting HI-E criteria of \>= 1.5 g/dL increase in hemoglobin (Hgb) sustained over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions from Week 1 Day 1 through Week 24. Participants who discontinued from the Treatment Period without achieving HI-E are counted as non-responders.

Secondary

MeasureTime frameDescription
Percentage of Participants Who Achieved Hematologic Improvement in Erythroid Response (HI-E) Per International Working Group (IWG) Through Week 48Week 1 Day 1 through Week 48Hematologic improvement is defined as the percent of participants meeting HI-E criteria of \>= 1.5 g/dL increase in hemoglobin (Hgb) sustained over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions from Week 1 Day 1 through Week 48 of the Treatment Period. Participants who discontinued from the Treatment Period without achieving HI-E are counted as non-responders.
Time to Hematologic Improvement in Erythroid Response (HI-E)Week 1 Day 1 through Week 24 and Week 48Defined as time from Week 1 Day 1 to first onset of achieving ≥ 1.5 g/dL increase in hemoglobin (Hgb) over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions.
Time to Modified Hematologic Improvement in Erythroid Response (mHI-E)Week 1 Day 1 through Week 24 and Week 48Defined as the time from Week 1 Day 1 to first onset of achieving ≥ 1.5 g/dL mean increase in hemoglobin (Hgb) compared to baseline over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions. Baseline Hgb is defined as the mean of the two central laboratory values (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1.
Duration of Hematologic Improvement in Erythroid Response (HI-E)Week 1 Day 1 through end of treatment period (up to an average of 74 weeks and maximum of 178 weeks)Defined as the maximum duration of achieving ≥ 1.5 g/dL increase in hemoglobin (Hgb) for participants who achieve Hgb increase ≥ 56 days in the absence of red blood cell (RBC) transfusions. Participants who maintain HI-E through the end of the Treatment Period or time of analysis will be censored at the date of treatment discontinuation/time of analysis or death, whichever occurs first.
Duration of Modified Hematologic Improvement in Erythroid Response (mHI-E)Week 1 Day 1 through end of treatment period (up to an average of 74 weeks and maximum of 178 weeks)Defined as the maximum duration of achieving ≥ 1.5 g/dL increase in hemoglobin for participants who achieve mean hemoglobin (Hgb) increase compared to baseline ≥ 56 days in the absence of red blood cell (RBC) transfusions. Participants who maintain mHI-E through the end of the Treatment Period or time of analysis will be censored at the date of treatment discontinuation/time of analysis or death, whichever occurs first. Baseline Hgb is defined as the mean of the two central laboratory values (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1.
Red Blood Cell Transfusion Independence (RBC-TI)Week 1 Day 1 through Week 24, Week 48, and Week 72Defined as the percentage of participants not being given any red blood cell (RBC) transfusion during the treatment period.
Progression to Acute Myeloid Leukemia (AML)From Week 1 Day 1 up to approximately 44 monthsNumber of participants progressing to acute myeloid leukemia (AML). AML progression is defined per WHO classification of ≥ 20% blasts in peripheral blood or bone marrow. Subjects with diagnosis of AML will be considered to have had an event. Subjects who have not progressed to AML at the time of analysis will be censored at the last assessment date which does not indicate progression to AML.
Percentage of Participants Who Achieved Modified Hematologic Improvement in Erythroid Response (mHI-E) Per International Working Group (IWG)Week 1 Day 1 through Week 24 and Week 48Modified hematologic improvement is defined as the percent of participants meeting mHI-E criteria of \>= 1.5 g/dL mean increase in hemoglobin (Hgb) compared to baseline sustained over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions from Week 1 Day 1 through Week 24 and Week 48 of the Treatment Period. Participants who discontinued from the Treatment Period without achieving mHI-E are counted as non-responders. Baseline Hgb is defined as the mean of the two central laboratory values (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1).
Overall SurvivalWeek 1 Day 1 to to a participants death date or last known alive date (up to approximately 44 months)Overall Survival is defined as time from Week 1 Day 1 to a participants death date or last known alive date. Participants who die, regardless of the cause of death, will be considered to have had an event. Participants who are alive at the time of analysis will be censored at the last assessment date at which the participant was known to be alive. All participants who were lost to follow-up will also be censored at the time of last contact.
Number of Participants With Adverse Events (AEs)From first dose to 42 days after last dose (up to approximately 42.5 months)Treatment-emergent adverse events include adverse events that started on or after the first dose until 42 days after the last dose, as well as those SAEs made known to the investigator at any time thereafter that are suspected of being related to study drug. An AE is any noxious, unintended, or untoward medical occurrence that may appear or worsen in a participant during the course of a study. Grade 3 = Severe Grade 4 = Life-threatening Grade 5 = Death
Maximum Plasma Concentration (Cmax)W1D1 (pre-dose), W1D3, W2D1, W2D3, W3D1, W4D1, W10D1, W13D1, W16D1, W17D1, W18D1, W19D1, W22D1, 24-Week MDS Disease Assessment, and every 12 weeks from the 24-Week MDS Disease Assessment Visit for up to 1 year from the first dose.
Time to Maximum Plasma Concentration (Tmax)W1D1 (pre-dose), W1D3, W2D1, W2D3, W3D1, W4D1, W10D1, W13D1, W16D1, W17D1, W18D1, W19D1, W22D1, 24-Week MDS Disease Assessment, and every 12 weeks from the 24-Week MDS Disease Assessment Visit for up to 1 year from the first dose.
Area Under the Concentration-Time Curve (AUC21d)W1D1 (pre-dose), W1D3, W2D1, W2D3 , W3D1, W4D1 (21 days after dose administration)
Number of Participants With a Positive Anti-Drug Antibody (ADA) TestW1D1 (must be collected before the first dose), W4D1, W10D1, W16D1, W22D1, 24-Week MDS Disease Assessment Visit and every 12 weeks (± 14 days) from the 24-Week MDS Disease Assessment Visit for up to 1 year from the first dose..Number of participants under each ADA positive category. A participant is counted as 'Treatment-Emergent' if there is a positive post-baseline sample while the baseline sample is ADA negative, or there is a positive post-baseline sample with a titer \>= 4-fold of the baseline titer while the baseline sample is ADA positive. A participant is counted as 'Preexisting' if the baseline sample is ADA positive and the participant is not qualified for 'Treatment-Emergent'. Positive to preexisting ADA is considered baseline sample is positive and all post-baseline samples are negative, or both baseline and post-baseline samples are positive, but all positive post-baseline sample have a titer \< 4-fold of the baseline titer.
Time to Acute Myeloid Leukemia (AML) ProgressionWeek 1 Day 1 to first diagnosis of AML (up to approximately 44 months)Defined as the time between W1D1 and first diagnosis of AML as per WHO classification of ≥ 20% blasts in peripheral blood or bone marrow. Participants with diagnosis of AML will be considered to have had an event. Participants who have not progressed to AML at the time of analysis will be censored at the last assessment date which does not indicate progression to AML.

Countries

Japan

Participant flow

Participants by arm

ArmCount
Luspatercept
Participants are administered luspatercept (ACE-536): starting dose of 1.0 mg/kg subcutaneous injection every 3 weeks (21 days; Q3W).
21
Total21

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyAdverse Event2
Overall StudyLack of Efficacy1
Overall StudyOther reasons11
Overall StudyProgressive Disease6
Overall StudyProtocol Deviation1

Baseline characteristics

CharacteristicLuspatercept
Age, Continuous74.5 Years
STANDARD_DEVIATION 8.47
Race/Ethnicity, Customized
Asian (Japanese)
21 Participants
Race/Ethnicity, Customized
Not Hispanic or Latino
21 Participants
Sex: Female, Male
Female
8 Participants
Sex: Female, Male
Male
13 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 21
other
Total, other adverse events
14 / 21
serious
Total, serious adverse events
6 / 21

Outcome results

Primary

Percentage of Participants Who Achieved Hematologic Improvement in Erythroid Response (HI-E) Per International Working Group (IWG) Through Week 24

Hematologic improvement is defined as the percent of participants meeting HI-E criteria of \>= 1.5 g/dL increase in hemoglobin (Hgb) sustained over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions from Week 1 Day 1 through Week 24. Participants who discontinued from the Treatment Period without achieving HI-E are counted as non-responders.

Time frame: Week 1 Day 1 through Week 24

Population: Intent-to-Treat Population: All enrolled participants regardless of whether or not the participant received luspatercept.

ArmMeasureValue (NUMBER)
LuspaterceptPercentage of Participants Who Achieved Hematologic Improvement in Erythroid Response (HI-E) Per International Working Group (IWG) Through Week 2447.6 Percentage of participants
Secondary

Area Under the Concentration-Time Curve (AUC21d)

Time frame: W1D1 (pre-dose), W1D3, W2D1, W2D3 , W3D1, W4D1 (21 days after dose administration)

Population: All participants who received at least 1 dose of luspatercept and had sufficient PK samples collected for non-compartmental analysis.

ArmMeasureValue (GEOMETRIC_MEAN)Dispersion
LuspaterceptArea Under the Concentration-Time Curve (AUC21d)94.28 Day*ug/mLGeometric Coefficient of Variation 29.31
Secondary

Duration of Hematologic Improvement in Erythroid Response (HI-E)

Defined as the maximum duration of achieving ≥ 1.5 g/dL increase in hemoglobin (Hgb) for participants who achieve Hgb increase ≥ 56 days in the absence of red blood cell (RBC) transfusions. Participants who maintain HI-E through the end of the Treatment Period or time of analysis will be censored at the date of treatment discontinuation/time of analysis or death, whichever occurs first.

Time frame: Week 1 Day 1 through end of treatment period (up to an average of 74 weeks and maximum of 178 weeks)

Population: All treated participants who achieve HI-E

ArmMeasureValue (MEDIAN)
LuspaterceptDuration of Hematologic Improvement in Erythroid Response (HI-E)40.0 Weeks
Secondary

Duration of Modified Hematologic Improvement in Erythroid Response (mHI-E)

Defined as the maximum duration of achieving ≥ 1.5 g/dL increase in hemoglobin for participants who achieve mean hemoglobin (Hgb) increase compared to baseline ≥ 56 days in the absence of red blood cell (RBC) transfusions. Participants who maintain mHI-E through the end of the Treatment Period or time of analysis will be censored at the date of treatment discontinuation/time of analysis or death, whichever occurs first. Baseline Hgb is defined as the mean of the two central laboratory values (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1.

Time frame: Week 1 Day 1 through end of treatment period (up to an average of 74 weeks and maximum of 178 weeks)

Population: All treated participants who achieve mHI-E

ArmMeasureValue (MEDIAN)
LuspaterceptDuration of Modified Hematologic Improvement in Erythroid Response (mHI-E)92.1 Weeks
Secondary

Maximum Plasma Concentration (Cmax)

Time frame: W1D1 (pre-dose), W1D3, W2D1, W2D3, W3D1, W4D1, W10D1, W13D1, W16D1, W17D1, W18D1, W19D1, W22D1, 24-Week MDS Disease Assessment, and every 12 weeks from the 24-Week MDS Disease Assessment Visit for up to 1 year from the first dose.

Population: All participants who received at least 1 dose of luspatercept and had sufficient PK samples collected for non-compartmental analysis.

ArmMeasureValue (GEOMETRIC_MEAN)Dispersion
LuspaterceptMaximum Plasma Concentration (Cmax)5.713 ug/mLGeometric Coefficient of Variation 29.27
Secondary

Number of Participants With Adverse Events (AEs)

Treatment-emergent adverse events include adverse events that started on or after the first dose until 42 days after the last dose, as well as those SAEs made known to the investigator at any time thereafter that are suspected of being related to study drug. An AE is any noxious, unintended, or untoward medical occurrence that may appear or worsen in a participant during the course of a study. Grade 3 = Severe Grade 4 = Life-threatening Grade 5 = Death

Time frame: From first dose to 42 days after last dose (up to approximately 42.5 months)

Population: Safety Population: All participants who were enrolled and received at least one dose of luspatercept.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
LuspaterceptNumber of Participants With Adverse Events (AEs)Treatment-Emergent Adverse Events (TEAEs)20 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Suspected Drug Related TEAE8 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Serious TEAE6 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Suspected Drug Related Serious TEAE1 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Grade 3 or 4 TEAE8 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Suspected Drug Related Grade 3 or 4 TEAE4 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Grade 5 TEAE0 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)Suspected Drug Related Grade 5 TEAE0 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)TEAE Leading to Dose Interruption5 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)TEAE Leading to Dose Reduction2 Participants
LuspaterceptNumber of Participants With Adverse Events (AEs)TEAE Leading to Dose Withdrawn6 Participants
Secondary

Number of Participants With a Positive Anti-Drug Antibody (ADA) Test

Number of participants under each ADA positive category. A participant is counted as 'Treatment-Emergent' if there is a positive post-baseline sample while the baseline sample is ADA negative, or there is a positive post-baseline sample with a titer \>= 4-fold of the baseline titer while the baseline sample is ADA positive. A participant is counted as 'Preexisting' if the baseline sample is ADA positive and the participant is not qualified for 'Treatment-Emergent'. Positive to preexisting ADA is considered baseline sample is positive and all post-baseline samples are negative, or both baseline and post-baseline samples are positive, but all positive post-baseline sample have a titer \< 4-fold of the baseline titer.

Time frame: W1D1 (must be collected before the first dose), W4D1, W10D1, W16D1, W22D1, 24-Week MDS Disease Assessment Visit and every 12 weeks (± 14 days) from the 24-Week MDS Disease Assessment Visit for up to 1 year from the first dose..

Population: Safety Population: all participants who were enrolled and received at least one dose of luspatercept.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
LuspaterceptNumber of Participants With a Positive Anti-Drug Antibody (ADA) TestPreexisting0 Participants
LuspaterceptNumber of Participants With a Positive Anti-Drug Antibody (ADA) TestTreatment-Emergent0 Participants
Secondary

Overall Survival

Overall Survival is defined as time from Week 1 Day 1 to a participants death date or last known alive date. Participants who die, regardless of the cause of death, will be considered to have had an event. Participants who are alive at the time of analysis will be censored at the last assessment date at which the participant was known to be alive. All participants who were lost to follow-up will also be censored at the time of last contact.

Time frame: Week 1 Day 1 to to a participants death date or last known alive date (up to approximately 44 months)

Population: Intent-to-Treat Population: All enrolled participants regardless of whether or not the participant received luspatercept.

ArmMeasureValue (MEDIAN)
LuspaterceptOverall SurvivalNA Months
Secondary

Percentage of Participants Who Achieved Hematologic Improvement in Erythroid Response (HI-E) Per International Working Group (IWG) Through Week 48

Hematologic improvement is defined as the percent of participants meeting HI-E criteria of \>= 1.5 g/dL increase in hemoglobin (Hgb) sustained over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions from Week 1 Day 1 through Week 48 of the Treatment Period. Participants who discontinued from the Treatment Period without achieving HI-E are counted as non-responders.

Time frame: Week 1 Day 1 through Week 48

Population: Intent-to-Treat Population: All enrolled participants regardless of whether or not the participant received luspatercept.

ArmMeasureValue (NUMBER)
LuspaterceptPercentage of Participants Who Achieved Hematologic Improvement in Erythroid Response (HI-E) Per International Working Group (IWG) Through Week 4857.1 Percentage of participants
Secondary

Percentage of Participants Who Achieved Modified Hematologic Improvement in Erythroid Response (mHI-E) Per International Working Group (IWG)

Modified hematologic improvement is defined as the percent of participants meeting mHI-E criteria of \>= 1.5 g/dL mean increase in hemoglobin (Hgb) compared to baseline sustained over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions from Week 1 Day 1 through Week 24 and Week 48 of the Treatment Period. Participants who discontinued from the Treatment Period without achieving mHI-E are counted as non-responders. Baseline Hgb is defined as the mean of the two central laboratory values (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1).

Time frame: Week 1 Day 1 through Week 24 and Week 48

Population: Intent-to-Treat Population: All enrolled participants regardless of whether or not the participant received luspatercept.

ArmMeasureGroupValue (NUMBER)
LuspaterceptPercentage of Participants Who Achieved Modified Hematologic Improvement in Erythroid Response (mHI-E) Per International Working Group (IWG)Week 1 Day 1 through Week 2457.1 Percentage of participants
LuspaterceptPercentage of Participants Who Achieved Modified Hematologic Improvement in Erythroid Response (mHI-E) Per International Working Group (IWG)Week 1 Day 1 through Week 4866.7 Percentage of participants
Secondary

Progression to Acute Myeloid Leukemia (AML)

Number of participants progressing to acute myeloid leukemia (AML). AML progression is defined per WHO classification of ≥ 20% blasts in peripheral blood or bone marrow. Subjects with diagnosis of AML will be considered to have had an event. Subjects who have not progressed to AML at the time of analysis will be censored at the last assessment date which does not indicate progression to AML.

Time frame: From Week 1 Day 1 up to approximately 44 months

Population: Intent-to-Treat Population: All enrolled participants regardless of whether or not the participant received luspatercept.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
LuspaterceptProgression to Acute Myeloid Leukemia (AML)0 Participants
Secondary

Red Blood Cell Transfusion Independence (RBC-TI)

Defined as the percentage of participants not being given any red blood cell (RBC) transfusion during the treatment period.

Time frame: Week 1 Day 1 through Week 24, Week 48, and Week 72

Population: Intent-to-Treat Population: All enrolled participants regardless of whether or not the participant received luspatercept.

ArmMeasureGroupValue (NUMBER)
LuspaterceptRed Blood Cell Transfusion Independence (RBC-TI)Week 1 Day 1 through Week 2481.0 Percentage of participants
LuspaterceptRed Blood Cell Transfusion Independence (RBC-TI)Week 1 Day 1 through Week 4881.0 Percentage of participants
LuspaterceptRed Blood Cell Transfusion Independence (RBC-TI)Week 1 Day 1 through Week 7281.0 Percentage of participants
Secondary

Time to Acute Myeloid Leukemia (AML) Progression

Defined as the time between W1D1 and first diagnosis of AML as per WHO classification of ≥ 20% blasts in peripheral blood or bone marrow. Participants with diagnosis of AML will be considered to have had an event. Participants who have not progressed to AML at the time of analysis will be censored at the last assessment date which does not indicate progression to AML.

Time frame: Week 1 Day 1 to first diagnosis of AML (up to approximately 44 months)

Population: All treated participants with AML progression. (No participants had AML progression)

Secondary

Time to Hematologic Improvement in Erythroid Response (HI-E)

Defined as time from Week 1 Day 1 to first onset of achieving ≥ 1.5 g/dL increase in hemoglobin (Hgb) over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions.

Time frame: Week 1 Day 1 through Week 24 and Week 48

Population: All treated participants who achieve HI-E until week 24 and 48.

ArmMeasureGroupValue (MEDIAN)
LuspaterceptTime to Hematologic Improvement in Erythroid Response (HI-E)Week 1 Day 1 through Week 2426.5 Days
LuspaterceptTime to Hematologic Improvement in Erythroid Response (HI-E)Week 1 Day 1 through Week 4836.5 Days
Secondary

Time to Maximum Plasma Concentration (Tmax)

Time frame: W1D1 (pre-dose), W1D3, W2D1, W2D3, W3D1, W4D1, W10D1, W13D1, W16D1, W17D1, W18D1, W19D1, W22D1, 24-Week MDS Disease Assessment, and every 12 weeks from the 24-Week MDS Disease Assessment Visit for up to 1 year from the first dose.

Population: All participants who received at least 1 dose of luspatercept and had sufficient PK samples collected for non-compartmental analysis.

ArmMeasureValue (MEDIAN)
LuspaterceptTime to Maximum Plasma Concentration (Tmax)7.921 Day
Secondary

Time to Modified Hematologic Improvement in Erythroid Response (mHI-E)

Defined as the time from Week 1 Day 1 to first onset of achieving ≥ 1.5 g/dL mean increase in hemoglobin (Hgb) compared to baseline over any consecutive 56-day period in the absence of red blood cell (RBC) transfusions. Baseline Hgb is defined as the mean of the two central laboratory values (one performed within 1 day prior to W1D1 and the other performed 7 to 35 days prior to W1D1.

Time frame: Week 1 Day 1 through Week 24 and Week 48

Population: All treated participants who achieve mHI-E until week 24 and 48.

ArmMeasureGroupValue (MEDIAN)
LuspaterceptTime to Modified Hematologic Improvement in Erythroid Response (mHI-E)Week 1 Day 1 through Week 240.0 Days
LuspaterceptTime to Modified Hematologic Improvement in Erythroid Response (mHI-E)Week 1 Day 1 through Week 480.0 Days

Source: ClinicalTrials.gov · Data processed: Feb 5, 2026