A Phase 2/3 interventional study of ABC008 in Inclusion Body Myositis, sponsored by Abcuro, Inc.. Completed at 45 sites in 7 countries. Open to participants aged 40 Years and older. Per ClinicalTrials.gov, last updated 2026-10-01.
Sponsored by Abcuro, Inc. · Phase 2/3, Interventional, and Treatment
A Phase II/III Randomized, Double-blind, Placebo-controlled, Multicenter Study to Determine the Efficacy and Safety of ABC008 in the Treatment of Subjects with Inclusion Body Myositis
A Phase II/III Randomized, Double-blind, Placebo-controlled, Multicenter Study to Determine the Efficacy and Safety of ABC008 in the Treatment of Subjects with Inclusion Body Myositis Detailed Description: A Phase II/III Randomized, Double-blind, Placebo-controlled, Multicenter Study to Determine the Efficacy and Safety of ABC008 in the Treatment of Subjects with Inclusion Body Myositis Detailed Description: This is a Phase II/III randomized, double-blind, placebo-controlled, parallel multicenter study with 3 parts.
The study will include a sentinel cohort (Part A) of 30 subjects who will receive first three doses of the study drug. Safety data from subjects in the sentinel cohorts will be evaluated by a Data and Safety Monitoring Board (DSMB) before further dosing of the sentinel cohort, as well as initiation of enrollment in the double-blind safety and efficacy cohort (Part B). After completion of Part A or Part B, subjects have the option of enrolling in an open-label long-term extension study or progressing to the pharmacodynamics (PD) recovery cohort (Part C), to evaluate the recovery of the depletion of killer cell lectin-like receptor G1 (KLRG1)+ cells after the end of treatment with ABC008.
Efficacy, safety, HRQoL, and HRU assessments will be conducted. Blood samples will be obtained to evaluate the serum PK, PD, and immunogenicity of ABC008 throughout the study.
49 studies on the registry are indexed under Myositis, Inclusion Body; 11 are open to participants now.
This study's enrollment of 272 is above the median of 27 across 30 interventional studies indexed under Myositis, Inclusion Body.
Browse Myositis, Inclusion Body studies →Abcuro, Inc. is the lead sponsor of 4 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Part A - ABC008 N=12 Part B - ABC008 N= 67
Drug: ABC008
Part A - ABC008 N=12 Part B - ABC008 N= 67
Drug: ABC008
Part A - Placebo N= 6 Part B - Placebo N= 67
Drug: ABC008
Given by subcutaneous injection
Part A: Number of Participants With Treatment Emergent Adverse Events (TEAEs)
An adverse event (AE) was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug.
Time frame: Up to Week 80
Part A: Number of Participants With TEAEs by Severity
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug and was graded by severity per protocol-specified Common Terminology Criteria for Adverse Events (CTCAE) criteria: Grade 1, Mild (asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated); Grade 2, Moderate (minimal, local, or noninvasive intervention indicated; limited age-appropriate instrumental activities of daily living (ADL)); Grade 3, Severe or medically significant (medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; or limiting self-care ADL); Grade 4, Life-threatening (threatening consequences; urgent intervention indicated); and Grade 5, Death (death related to an AE).
Time frame: Up to Week 80
Part A: Number of Participants With TEAEs Related to Study Drug
An AE was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug. An AE with missing relationship to study drug was considered as related to study drug.
Time frame: Up to Week 80
Part A: Mean Change From Baseline in the Inclusion Body Myositis Functional Rating Scale (IBMFRS) Total Score at Week 76
The IBMFRS was used as an ordinal rating scale to determine participant's assessments of their capabilities. It included 10 measures (swallowing, handwriting, cutting food and handling utensils, fine motor tasks, dressing, hygiene, turning in bed and adjusting covers, changing position from sitting to standing, walking, and climbing stairs) graded on a Likert scale (a psychometric tool) from 0 (being unable to perform) to 4 (normal). The sum of the 10 items provided a value between 0 and 40, with a higher score representing less functional limitation or better functional status. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) and at Week 76
Part B: Number of Participants With TEAEs
An AE was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug.
Time frame: Day 1 to Week 80
Part B: Number of Participants With TEAEs by Severity
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug and was graded by severity per protocol-specified CTCAE criteria: Grade 1, Mild (asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated); Grade 2, Moderate (minimal, local, or noninvasive intervention indicated; limited age-appropriate instrumental ADL); Grade 3, Severe or medically significant (medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; or limiting self-care ADL); Grade 4, Life-threatening (threatening consequences; urgent intervention indicated); and Grade 5, Death (death related to an AE).
Time frame: Day 1 to Week 80
Part B: Number of Participants With TEAEs Related to Study Drug
An AE was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug. An AE with missing relationship to study drug was considered as related to study drug.
Time frame: Day 1 to Week 80
Part B: Mean Change From Baseline in the IBMFRS Total Score at Week 76
The IBMFRS was used as an ordinal rating scale to determine participant's assessments of their capabilities. It included 10 measures (swallowing, handwriting, cutting food and handling utensils, fine motor tasks, dressing, hygiene, turning in bed and adjusting covers, changing position from sitting to standing, walking, and climbing stairs) graded on a Likert scale (a psychometric tool) from 0 (being unable to perform) to 4 (normal). The sum of the 10 items provided a value between 0 and 40, with a higher score representing less functional limitation or better functional status. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) and Up to Week 76
Part C: Time to PD Recovery
Recovery was defined as the return of KLRG1+ cell counts toward baseline levels during the PD follow-up period.
Time frame: Up to Week 24
Part A and B: Number of Participants With Treatment-emergent Serious Adverse Events (TESAEs)
A TESAE was defined as a serious AE that first occurred or worsened after initiation of study drug and met seriousness criteria per protocol (including death, life-threatening event, hospitalization or prolongation of hospitalization, persistent or significant disability/incapacity, congenital anomaly, or other medically important event).
Time frame: Up to Week 80
Part A and B: Number of Participants With TEAEs With Onset Within 24 Hours From the Start of Any Study Medication Administration
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug, with onset assessed within 24 hours following the dosing.
Time frame: Within 24 hours following each dose, Up to Week 80
Part A and B: Number of Participants With TEAEs Leading to Study Discontinuation
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug that led to discontinuation of study.
Time frame: Up to Week 80
Part A and B: Change From Baseline in Hematology Parameters - Absolute Neutrophil Count, Basophils, Eosinophils, Leukocytes, Lymphocytes, Monocytes, Neutrophils, and Platelets
Blood samples were collected for the analysis of hematology parameters: Absolute Neutrophil Count, Basophils, Eosinophils, Leukocytes, Lymphocytes, Monocytes, Neutrophils, and Platelets. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Hematology Parameter - Erythrocytes
Blood samples were collected for the analysis of hematology parameter Erythrocytes. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Hematology Parameters - Hemoglobin and Erythrocyte Mean Corpuscular Hemoglobin Concentration
Blood samples were collected for the analysis of hematology parameters: Hemoglobin and Erythrocyte Mean Corpuscular Hemoglobin Concentration. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Hematology Parameter - Erythrocyte Mean Corpuscular Hemoglobin
Blood samples were collected for the analysis of hematology parameters: Hemoglobin and Erythrocyte Mean Corpuscular Hemoglobin. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Hematology Parameters - Erythrocyte Mean Corpuscular Volume
Blood samples were collected for the analysis of hematology parameter Erythrocyte Mean Corpuscular Volume. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Hematology Parameters - Hematocrit
Blood samples were collected for the analysis of hematology parameter Hematocrit. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Blood Chemistry Parameters - Alanine Aminotransferase (ALT), Aldolase, Gamma Glutamyl Transferase (GGT), Lactate Dehydrogenase, Aspartate Aminotransferase (AST)
Blood samples were collected for the analysis of blood chemistry parameters: ALT, Aldolase, AST, GGT and Lactate Dehydrogenase. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Blood Chemistry Parameters - Albumin and Protein
Blood samples were collected for the analysis of blood chemistry parameters Albumin and Protein. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Blood Chemistry Parameters - Alkaline Phosphatase and Creatine Kinase (CK)
Blood samples were collected for the analysis of blood chemistry parameters Alkaline Phosphatase and CK. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Blood Chemistry Parameters - Bicarbonate, Calcium, Chloride, Glucose, Potassium, Sodium and Urea
Blood samples were collected for the analysis of blood chemistry parameters: Bicarbonate, Calcium, Chloride, Glucose, Potassium, and Urea. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Blood Chemistry Parameters - Bilirubin, Creatinine and Urate
Blood samples were collected for the analysis of blood chemistry parameters: Bilirubin, Creatinine, and Urate. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Urinalysis Parameter - pH
Urine samples were collected for the analysis of Urinalysis parameter: pH. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Urinalysis Parameter- Specific Gravity
Urine samples were collected for the analysis of Urinalysis parameters- specific gravity. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Complement Parameters - C3 and C4
Blood samples were collected for the analysis of complement parameters included C3 and C4. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in Complement Parameters - Hemolytic Complement Filtration (CH50)
Blood samples were collected for the analysis of complement parameter- hemolytic complement filtration (CH50). Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in C Reactive Protein (CRP)
Blood samples were collected for the analysis of blood chemistry parameter- CRP. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Number of Participants With Clinically Significant Changes in Vital Signs
Vital signs were planned to be measured after 5 minutes of rest and taken in the same position throughout the study. Vital signs included blood pressure, pulse, temperature, and respiration rate. Clinically significant changes in vital signs were defined according to protocol-specified criteria for abnormal values (or clinically significant worsening from baseline) as determined by the Investigator.
Time frame: Up to Week 76
Part A and B: Change From Baseline in Electrocardiogram (ECG) Mean Heart Rate
Triplicate 12-lead ECG was recorded with the participant in a supine position for at least 5 minutes. Changes in ECG parameters were defined according to protocol-specified criteria for change from baseline values as determined by the Investigator. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-baseline visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Change From Baseline in ECG Parameters: PR Interval, QRS Duration, QT Interval and Interval Corrected Using Fridericia's Formula (QTcF) Interval
Triplicate 12-lead ECG was recorded with the participant in a supine position for at least 5 minutes. Changes in ECG parameters were defined according to protocol-specified criteria for change from baseline values as determined by the Investigator. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) to Week 76
Part A and B: Number of Participants With Treatment-emergent Adverse Events of Special Interest (AESI)
An AE was defined as any untoward medical occurrence in any participant partaking in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. AESIs included injection site reactions, systemic injection reactions (e.g., hypersensitivity, systemic inflammatory response), and infection.
Time frame: Up to Week 80
Part A and B: Mean Change From Baseline in the Manual Muscle Testing - 12 (MMT-12) Score at Week 76
Manual Muscle Testing - 12 assessed the muscle strength across the muscle groups that included neck flexion and both right and left shoulder abduction, elbow flexion, elbow extension, wrist extension, wrist flexion, flexor pollicis longus, hip flexors, hip abduction, hip extension, knee extension, and ankle dorsiflexion. Scores were calculated by summing the outcomes, with the Investigator providing the score, on a scale of 0 (no contraction) to 5 (normal strength), which is then converted by a standard procedure to a Kendall score equivalent on a scale of 0 to 10. Individual scores are summed to generate a total score ranging from 0 to 60. A higher score reflects better muscle strength. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) and up to Week 76
Part A and B: Mean Change From Baseline in the Hand Grip Strength Score by Dynamometry at Week 76
Grip strength was assessed using a handheld dynamometer which provided a precise measurement of the force that a muscle can exert and reflects muscle strength of the hand. Positive values indicated increased grip strength and negative values indicated decreased grip strength. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) and up to Week 76
Part A and B: Mean Change From Baseline in the Quadriceps Strength Score by Dynamometry at Week 76
Quadriceps strength was measured using a dynamometer which provided the applied force of leg extension and reflects muscle strength of the dominant leg. Positive values indicated increased strength and negative values indicated decreased strength. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) and up to Week 76
Part A and B: Mean Change From Baseline in Modified Timed Up and Go Test (mTUG) at Week 76
The mTUG assessed functional mobility by measuring the time required for a participant to rise from a standard armchair, walk 3 meters, turn around, walk back to the chair, and sit down (assistive devices permitted after standing, but no support from a caregiver, or a wall). Negative values indicated faster performance and positive values indicated slower performance. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
Time frame: Baseline (Day 1) and up to Week 76
A total of 272 participants were enrolled from multiple sites in United States, Canada, UK, Europe, and Australia.
| Milestone | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Part C: PD Recovery and Safety Follow-Up |
|---|---|---|---|---|---|---|---|
| Started | 9 | 17 | 17 | 0 | 0 | 0 | 0 |
| Completed | 9 | 17 | 17 | 0 | 0 | 0 | 0 |
| Not completed | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Milestone | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Part C: PD Recovery and Safety Follow-Up |
|---|---|---|---|---|---|---|---|
| Started | 0 | 0 | 0 | 77 | 75 | 77 | 0 |
| Completed | 0 | 0 | 0 | 71 | 73 | 75 | 0 |
| Not completed | 0 | 0 | 0 | 6 | 2 | 2 | 0 |
| Withdrew: Adverse event | 0 | 0 | 0 | 2 | 1 | 0 | 0 |
| Withdrew: Withdrawal by subject | 0 | 0 | 0 | 2 | 0 | 1 | 0 |
| Withdrew: Death | 0 | 0 | 0 | 1 | 0 | 1 | 0 |
| Withdrew: Other | 0 | 0 | 0 | 1 | 1 | 0 | 0 |
| Milestone | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Part C: PD Recovery and Safety Follow-Up |
|---|---|---|---|---|---|---|---|
| Started | 0 | 0 | 0 | 0 | 0 | 0 | 4 |
| Completed | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Not completed | 0 | 0 | 0 | 0 | 0 | 0 | 4 |
| Withdrew: Withdrawal by subject | 0 | 0 | 0 | 0 | 0 | 0 | 4 |
An adverse event (AE) was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug.
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Part A: Number of Participants With Treatment Emergent Adverse Events (TEAEs) | 8 | 17 | 17 |
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug and was graded by severity per protocol-specified Common Terminology Criteria for Adverse Events (CTCAE) criteria: Grade 1, Mild (asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated); Grade 2, Moderate (minimal, local, or noninvasive intervention indicated; limited age-appropriate instrumental activities of daily living (ADL)); Grade 3, Severe or medically significant (medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; or limiting self-care ADL); Grade 4, Life-threatening (threatening consequences; urgent intervention indicated); and Grade 5, Death (death related to an AE).
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Mild (Grade 1) | 2 | 3 | 4 |
| Moderate (Grade 2) | 4 | 10 | 10 |
| Severe (Grade 3) | 2 | 4 | 3 |
| Life-threatening (Grade 4) | 0 | 0 | 0 |
| Death (Grade 5) | 0 | 0 | 0 |
An AE was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug. An AE with missing relationship to study drug was considered as related to study drug.
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Part A: Number of Participants With TEAEs Related to Study Drug | 3 | 15 | 13 |
The IBMFRS was used as an ordinal rating scale to determine participant's assessments of their capabilities. It included 10 measures (swallowing, handwriting, cutting food and handling utensils, fine motor tasks, dressing, hygiene, turning in bed and adjusting covers, changing position from sitting to standing, walking, and climbing stairs) graded on a Likert scale (a psychometric tool) from 0 (being unable to perform) to 4 (normal). The sum of the 10 items provided a value between 0 and 40, with a higher score representing less functional limitation or better functional status. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| score on a scale | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Part A: Mean Change From Baseline in the Inclusion Body Myositis Functional Rating Scale (IBMFRS) Total Score at Week 76 | -2.7 (-4.8 to -0.7) | -2.4 (-3.9 to -0.9) | -2.2 (-3.7 to -0.7) |
An AE was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug.
| Participants | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Part B: Number of Participants With TEAEs | 76 | 75 | 74 |
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug and was graded by severity per protocol-specified CTCAE criteria: Grade 1, Mild (asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated); Grade 2, Moderate (minimal, local, or noninvasive intervention indicated; limited age-appropriate instrumental ADL); Grade 3, Severe or medically significant (medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; or limiting self-care ADL); Grade 4, Life-threatening (threatening consequences; urgent intervention indicated); and Grade 5, Death (death related to an AE).
| Participants | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Mild (Grade 1) | 20 | 32 | 16 |
| Moderate (Grade 2) | 40 | 33 | 41 |
| Severe (Grade 3) | 13 | 10 | 16 |
| Life-threatening (Grade 4) | 1 | 0 | 0 |
| Death (Grade 5) | 2 | 0 | 1 |
An AE was defined as any untoward medical occurrence in any participant participating in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. A TEAE was defined as an AE that first occurred or worsened after initiation of study drug. An AE with missing relationship to study drug was considered as related to study drug.
| Participants | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Part B: Number of Participants With TEAEs Related to Study Drug | 28 | 39 | 51 |
The IBMFRS was used as an ordinal rating scale to determine participant's assessments of their capabilities. It included 10 measures (swallowing, handwriting, cutting food and handling utensils, fine motor tasks, dressing, hygiene, turning in bed and adjusting covers, changing position from sitting to standing, walking, and climbing stairs) graded on a Likert scale (a psychometric tool) from 0 (being unable to perform) to 4 (normal). The sum of the 10 items provided a value between 0 and 40, with a higher score representing less functional limitation or better functional status. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| score on a scale | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|
| Part B: Mean Change From Baseline in the IBMFRS Total Score at Week 76 | -2.4 (-3.1 to -1.8) | -1.6 (-2.2 to -0.9) | -2.0 (-2.6 to -1.4) |
Recovery was defined as the return of KLRG1+ cell counts toward baseline levels during the PD follow-up period.
| hours | Part C: PD Recovery and Safety Follow-Up |
|---|---|
| Part C: Time to PD Recovery | NA (NA to NA) |
A TESAE was defined as a serious AE that first occurred or worsened after initiation of study drug and met seriousness criteria per protocol (including death, life-threatening event, hospitalization or prolongation of hospitalization, persistent or significant disability/incapacity, congenital anomaly, or other medically important event).
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Number of Participants With Treatment-emergent Serious Adverse Events (TESAEs) | 2 | 2 | 3 | 16 | 6 | 9 |
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug, with onset assessed within 24 hours following the dosing.
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Number of Participants With TEAEs With Onset Within 24 Hours From the Start of Any Study Medication Administration | 2 | 10 | 12 | 21 | 36 | 45 |
A TEAE was defined as an AE that first occurred or worsened after initiation of study drug that led to discontinuation of study.
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Number of Participants With TEAEs Leading to Study Discontinuation | 0 | 0 | 0 | 2 | 0 | 0 |
Blood samples were collected for the analysis of hematology parameters: Absolute Neutrophil Count, Basophils, Eosinophils, Leukocytes, Lymphocytes, Monocytes, Neutrophils, and Platelets. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| 10^9 cells per liter | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Absolute Neutrophil Count | -0.030 ± 1.7759 | -0.995 ± 1.9932 | -0.432 ± 0.8482 | -0.255 ± 1.0776 | -0.537 ± 1.5477 | -0.753 ± 1.3915 |
| Basophils | -0.002 ± 0.0307 | -0.010 ± 0.0326 | -0.005 ± 0.0200 | -0.005 ± 0.0242 | -0.010 ± 0.0324 | -0.010 ± 0.0301 |
| Eosinophils | 0.073 ± 0.1119 | -0.082 ± 0.0888 | -0.068 ± 0.1037 | -0.002 ± 0.1153 | -0.041 ± 0.0872 | -0.067 ± 0.1131 |
| Leukocytes | 0.11 ± 2.165 | -1.59 ± 2.187 | -0.91 ± 1.179 | -0.42 ± 1.157 | -1.03 ± 1.647 | -1.48 ± 1.603 |
| Lymphocytes | 0.067 ± 0.3163 | -0.454 ± 0.5320 | -0.453 ± 0.4102 | -0.083 ± 0.3666 | -0.410 ± 0.4602 | -0.611 ± 0.5058 |
| Monocytes | 0.000 ± 0.1928 | -0.049 ± 0.1647 | 0.040 ± 0.0929 | -0.067 ± 0.1582 | -0.026 ± 0.1258 | -0.047 ± 0.1680 |
| Neutrophils | -0.030 ± 1.7759 | -0.995 ± 1.9932 | -0.432 ± 0.8482 | -0.251 ± 1.0784 | -0.540 ± 1.5367 | -0.753 ± 1.3915 |
| Platelets | 4.7 ± 26.35 | -14.4 ± 40.46 | -7.2 ± 18.35 | -5.2 ± 31.09 | -16.1 ± 36.35 | -15.9 ± 33.30 |
Blood samples were collected for the analysis of hematology parameter Erythrocytes. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| 10^12 cells per liter | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Hematology Parameter - Erythrocytes | 0.07 ± 0.421 | -0.04 ± 0.245 | -0.06 ± 0.213 | -0.02 ± 0.261 | 0.05 ± 0.291 | 0.00 ± 0.245 |
Blood samples were collected for the analysis of hematology parameters: Hemoglobin and Erythrocyte Mean Corpuscular Hemoglobin Concentration. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| gram per liter (g/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Hemoglobin | 2.1 ± 10.43 | -2.3 ± 7.11 | -1.4 ± 6.16 | -1.4 ± 8.00 | 1.1 ± 10.96 | 0.4 ± 6.34 |
| Erythrocyte Mean Corpuscular Hemoglobin Concentration | -6.2 ± 10.49 | -4.9 ± 7.42 | 0.9 ± 3.48 | -0.6 ± 8.43 | -1.4 ± 8.10 | 2.5 ± 7.78 |
Blood samples were collected for the analysis of hematology parameters: Hemoglobin and Erythrocyte Mean Corpuscular Hemoglobin. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| picograms per cell | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Hematology Parameter - Erythrocyte Mean Corpuscular Hemoglobin | 0.1 ± 0.93 | -0.1 ± 0.99 | 0.2 ± 0.66 | -0.2 ± 0.86 | -0.1 ± 1.31 | 0.2 ± 1.03 |
Blood samples were collected for the analysis of hematology parameter Erythrocyte Mean Corpuscular Volume. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| femtoliter (fL) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Hematology Parameters - Erythrocyte Mean Corpuscular Volume | 1.9 ± 4.08 | 0.6 ± 2.69 | 0.4 ± 1.67 | -0.3 ± 2.43 | 0.2 ± 3.10 | -0.1 ± 2.81 |
Blood samples were collected for the analysis of hematology parameter Hematocrit. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| percent by volume [%(v/v)] | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Hematology Parameters - Hematocrit | 0.017 ± 0.0361 | -0.001 ± 0.0237 | -0.004 ± 0.0213 | -0.003 ± 0.0258 | 0.005 ± 0.0318 | -0.002 ± 0.0217 |
Blood samples were collected for the analysis of blood chemistry parameters: ALT, Aldolase, AST, GGT and Lactate Dehydrogenase. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| units per liter (U/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| ALT | -7.7 ± 9.12 | -12.8 ± 10.60 | -4.1 ± 7.79 | -5.7 ± 11.55 | -1.2 ± 12.40 | -4.0 ± 11.29 |
| Aldolase | -1.06 ± 2.130 | -1.89 ± 2.159 | -1.82 ± 2.455 | -1.17 ± 2.237 | -0.26 ± 2.115 | -0.88 ± 2.989 |
| GGT | -2.9 ± 16.86 | -2.6 ± 11.52 | -2.2 ± 10.82 | 0.7 ± 19.76 | 1.7 ± 27.41 | 2.9 ± 22.16 |
| Lactate Dehydrogenase | -36.7 ± 24.85 | -17.3 ± 38.47 | -20.6 ± 32.82 | -12.7 ± 47.09 | 0.6 ± 35.86 | -11.1 ± 54.65 |
| AST | -7.6 ± 7.23 | -8.6 ± 8.17 | -2.9 ± 7.12 | -4.6 ± 11.27 | -0.4 ± 9.67 | -2.4 ± 8.68 |
Blood samples were collected for the analysis of blood chemistry parameters Albumin and Protein. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| gram per litre (g/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Albumin | -0.9 ± 2.09 | -0.5 ± 2.43 | -0.5 ± 2.40 | 0.1 ± 2.27 | 0.4 ± 2.40 | 0.8 ± 1.88 |
| Protein | -0.3 ± 3.32 | 1.4 ± 3.77 | 0.8 ± 3.15 | -0.5 ± 3.85 | 0.2 ± 3.86 | 0.8 ± 3.41 |
Blood samples were collected for the analysis of blood chemistry parameters Alkaline Phosphatase and CK. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| International units per liter (IU/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Alkaline Phosphatase | -1.7 ± 11.21 | 2.4 ± 12.63 | 0.7 ± 9.25 | 0.8 ± 17.56 | 1.1 ± 13.95 | 1.8 ± 12.38 |
| CK | -76.9 ± 128.55 | -192.6 ± 205.91 | -140.2 ± 189.53 | -89.6 ± 190.75 | -69.9 ± 179.03 | -134.1 ± 271.63 |
Blood samples were collected for the analysis of blood chemistry parameters: Bicarbonate, Calcium, Chloride, Glucose, Potassium, and Urea. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| millimoles per liter (mmol/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Bicarbonate | -2.6 ± 2.01 | -1.6 ± 3.50 | -1.3 ± 1.88 | -1.5 ± 2.53 | -1.5 ± 2.17 | -1.9 ± 2.25 |
| Calcium | -0.047 ± 0.1092 | -0.058 ± 0.0948 | -0.008 ± 0.0748 | -0.048 ± 0.0813 | -0.024 ± 0.1016 | -0.022 ± 0.0749 |
| Chloride | -0.9 ± 3.22 | -1.0 ± 3.46 | -0.5 ± 1.94 | -0.5 ± 3.05 | 0.0 ± 2.41 | -0.5 ± 2.82 |
| Glucose | 0.14 ± 1.201 | 0.15 ± 1.236 | -0.59 ± 1.620 | -0.09 ± 1.394 | -0.28 ± 1.420 | -0.14 ± 1.222 |
| Potassium | -0.03 ± 0.418 | -0.19 ± 0.435 | 0.04 ± 0.411 | 0.00 ± 0.347 | -0.12 ± 0.463 | -0.08 ± 0.346 |
| Sodium | -1.1 ± 1.83 | -1.1 ± 4.02 | -0.4 ± 2.42 | -1.1 ± 2.75 | -0.1 ± 2.26 | -0.3 ± 2.86 |
| Urea | 0.817 ± 1.6766 | -0.680 ± 1.6260 | -0.024 ± 0.9662 | -0.077 ± 1.7805 | 0.001 ± 1.6092 | 0.198 ± 1.4200 |
Blood samples were collected for the analysis of blood chemistry parameters: Bilirubin, Creatinine, and Urate. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| micromoles per liter (umol/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Bilirubin | -0.7 ± 2.29 | -0.4 ± 3.26 | -0.6 ± 2.55 | -0.2 ± 2.67 | -0.1 ± 2.82 | 0.4 ± 4.30 |
| Creatinine | -8.0 ± 3.00 | -8.9 ± 8.00 | -8.5 ± 4.45 | -6.3 ± 10.77 | -6.4 ± 6.20 | -5.8 ± 8.09 |
| Urate | -34.3 ± 66.95 | -32.5 ± 67.70 | -11.1 ± 50.37 | -19.9 ± 68.33 | -6.3 ± 45.68 | 1.4 ± 68.00 |
Urine samples were collected for the analysis of Urinalysis parameter: pH. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| potential of Hydrogen | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Urinalysis Parameter - pH | -0.06 ± 1.102 | -0.03 ± 0.892 | -0.03 ± 0.624 | 0.14 ± 0.899 | 0.26 ± 0.888 | 0.07 ± 0.794 |
Urine samples were collected for the analysis of Urinalysis parameters- specific gravity. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| Ratio of urine density to water density | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Urinalysis Parameter- Specific Gravity | -0.0021 ± 0.01129 | -0.0010 ± 0.00745 | 0.0014 ± 0.00727 | 0.0002 ± 0.00711 | -0.0002 ± 0.00542 | -0.0007 ± 0.00540 |
Blood samples were collected for the analysis of complement parameters included C3 and C4. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| milligram per liter (mg/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Complement C3 | 48.6 ± 263.59 | 136.7 ± 288.89 | 142.1 ± 328.69 | 29.2 ± 123.33 | 26.1 ± 146.34 | 42.4 ± 210.70 |
| Complement C4 | 21.6 ± 47.65 | 28.4 ± 64.46 | 38.6 ± 96.91 | -2.1 ± 29.74 | -0.4 ± 30.40 | -1.7 ± 34.41 |
Blood samples were collected for the analysis of complement parameter- hemolytic complement filtration (CH50). Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| units per milliliter (U/mL) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Complement Parameters - Hemolytic Complement Filtration (CH50) | 0.0 ± 0.50 | -0.3 ± 3.31 | -0.3 ± 3.60 | 0.9 ± 7.41 | -0.6 ± 1.66 | 0.1 ± 1.80 |
Blood samples were collected for the analysis of blood chemistry parameter- CRP. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| milligram per liter (mg/L) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in C Reactive Protein (CRP) | -1.8 ± 7.33 | -2.7 ± 5.74 | 0.3 ± 2.31 | 1.0 ± 10.38 | -0.2 ± 3.23 | 0.6 ± 10.00 |
Vital signs were planned to be measured after 5 minutes of rest and taken in the same position throughout the study. Vital signs included blood pressure, pulse, temperature, and respiration rate. Clinically significant changes in vital signs were defined according to protocol-specified criteria for abnormal values (or clinically significant worsening from baseline) as determined by the Investigator.
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Number of Participants With Clinically Significant Changes in Vital Signs | 0 | 0 | 0 | 0 | 0 | 0 |
Triplicate 12-lead ECG was recorded with the participant in a supine position for at least 5 minutes. Changes in ECG parameters were defined according to protocol-specified criteria for change from baseline values as determined by the Investigator. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-baseline visits minus the Baseline.
| beats/min | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Change From Baseline in Electrocardiogram (ECG) Mean Heart Rate | 0.3 ± 13.71 | 1.0 ± 7.14 | -0.6 ± 6.48 | -1.6 ± 9.08 | -2.4 ± 7.66 | -0.6 ± 11.38 |
Triplicate 12-lead ECG was recorded with the participant in a supine position for at least 5 minutes. Changes in ECG parameters were defined according to protocol-specified criteria for change from baseline values as determined by the Investigator. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| milliseconds | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| PR Interval | -0.9 ± 12.40 | 3.8 ± 11.48 | 1.9 ± 13.46 | 0.7 ± 10.88 | 3.6 ± 13.61 | 2.7 ± 11.94 |
| QRS Duration | -0.5 ± 5.16 | 1.4 ± 5.85 | 1.2 ± 11.23 | -0.5 ± 7.36 | 1.3 ± 7.97 | -0.4 ± 5.24 |
| QT Interval | -3.5 ± 32.13 | -1.0 ± 17.80 | 2.7 ± 14.42 | -0.5 ± 22.53 | 3.8 ± 20.82 | 2.3 ± 26.81 |
| QTcF Interval | -5.5 ± 16.19 | 1.3 ± 13.98 | 2.1 ± 13.24 | -3.7 ± 12.26 | -1.4 ± 11.93 | 0.7 ± 12.22 |
An AE was defined as any untoward medical occurrence in any participant partaking in a clinical investigation, regardless of the suspected cause. An AE was therefore can be any unfavorable and unintended sign, symptom, disease, concurrent illness, or clinically significant abnormal laboratory finding that emerged or worsened during the study. AESIs included injection site reactions, systemic injection reactions (e.g., hypersensitivity, systemic inflammatory response), and infection.
| Participants | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Number of Participants With Treatment-emergent Adverse Events of Special Interest (AESI) | 6 | 15 | 15 | 51 | 55 | 63 |
Manual Muscle Testing - 12 assessed the muscle strength across the muscle groups that included neck flexion and both right and left shoulder abduction, elbow flexion, elbow extension, wrist extension, wrist flexion, flexor pollicis longus, hip flexors, hip abduction, hip extension, knee extension, and ankle dorsiflexion. Scores were calculated by summing the outcomes, with the Investigator providing the score, on a scale of 0 (no contraction) to 5 (normal strength), which is then converted by a standard procedure to a Kendall score equivalent on a scale of 0 to 10. Individual scores are summed to generate a total score ranging from 0 to 60. A higher score reflects better muscle strength. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| score on a scale | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Mean Change From Baseline in the Manual Muscle Testing - 12 (MMT-12) Score at Week 76 | -3.6 (-14.6 to 7.4) | -1.7 (-9.8 to 6.5) | -5.9 (-14.0 to 2.3) | -7.9 (-11.7 to -4.1) | -3.6 (-7.4 to 0.3) | -7.1 (-10.9 to -3.3) |
Grip strength was assessed using a handheld dynamometer which provided a precise measurement of the force that a muscle can exert and reflects muscle strength of the hand. Positive values indicated increased grip strength and negative values indicated decreased grip strength. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| kilograms | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Mean Change From Baseline in the Hand Grip Strength Score by Dynamometry at Week 76 | 0.6 (-2.1 to 3.2) | 0.1 (-1.9 to 2.0) | -1.9 (-3.9 to 0.0) | -1.2 (-1.9 to -0.6) | -0.6 (-1.3 to 0.1) | -0.8 (-1.4 to -0.1) |
Quadriceps strength was measured using a dynamometer which provided the applied force of leg extension and reflects muscle strength of the dominant leg. Positive values indicated increased strength and negative values indicated decreased strength. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| kilograms | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Mean Change From Baseline in the Quadriceps Strength Score by Dynamometry at Week 76 | 1.2 (-1.7 to 4.1) | 1.0 (-1.2 to 3.3) | 0.9 (-1.3 to 3.1) | -1.5 (-2.5 to -0.5) | -0.6 (-1.6 to 0.4) | -1.6 (-2.6 to -0.6) |
The mTUG assessed functional mobility by measuring the time required for a participant to rise from a standard armchair, walk 3 meters, turn around, walk back to the chair, and sit down (assistive devices permitted after standing, but no support from a caregiver, or a wall). Negative values indicated faster performance and positive values indicated slower performance. Baseline value was defined as the last non-missing valid value prior to first administration of study treatment (on Day 1). Change from Baseline was calculated as the data collected at post-randomization visits minus the Baseline.
| seconds | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg |
|---|---|---|---|---|---|---|
| Part A and B: Mean Change From Baseline in Modified Timed Up and Go Test (mTUG) at Week 76 | 3.5 (-7.2 to 14.2) | 6.9 (-1.7 to 15.6) | 4.4 (-4.1 to 13.0) | 4.4 (-0.6 to 9.4) | 7.1 (1.8 to 12.4) | 6.3 (0.4 to 12.2) |
Collected over Day 1 through Week 80. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Part A: Placebo | 0/9 (0%) | 2/9 (22.2%) | 8/9 (88.9%) |
| Part A: Ulviprubart 0.5 mg/kg | 0/17 (0%) | 2/17 (11.8%) | 17/17 (100%) |
| Part A: Ulviprubart 2.0 mg/kg | 0/17 (0%) | 3/17 (17.6%) | 17/17 (100%) |
| Part B: Placebo | 2/77 (2.6%) | 16/77 (20.8%) | 76/77 (98.7%) |
| Part B: Ulviprubart 0.5 mg/kg | 0/75 (0%) | 6/75 (8%) | 75/75 (100%) |
| Part B: Ulviprubart 2.0 mg/kg | 1/77 (1.3%) | 9/77 (11.7%) | 74/77 (96.1%) |
| Part C: PD Recovery and Safety Follow-Up | 0/4 (0%) | 0/4 (0%) | 1/4 (25%) |
| Event | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Part C: PD Recovery and Safety Follow-Up |
|---|---|---|---|---|---|---|---|
| PneumoniaInfections and infestations | 0/9 | 0/17 | 2/17 | 0/77 | 0/75 | 0/77 | 0/4 |
| Appendicitis perforatedInfections and infestations | 1/9 | 0/17 | 0/17 | 0/77 | 0/75 | 0/77 | 0/4 |
| Pneumonia aspirationInfections and infestations | 1/9 | 0/17 | 0/17 | 2/77 | 0/75 | 1/77 | 0/4 |
| OsteomyelitisInfections and infestations | 0/9 | 0/17 | 1/17 | 0/77 | 0/75 | 0/77 | 0/4 |
| Acute myocardial infarctionCardiac disorders | 0/9 | 1/17 | 0/17 | 0/77 | 0/75 | 0/77 | 0/4 |
| Coronary artery diseaseCardiac disorders | 0/9 | 1/17 | 0/17 | 0/77 | 0/75 | 0/77 | 0/4 |
| Bile duct stoneHepatobiliary disorders | 0/9 | 1/17 | 0/17 | 0/77 | 0/75 | 0/77 | 0/4 |
| Rib fractureInjury, poisoning and procedural complications | 0/9 | 0/17 | 0/17 | 0/77 | 2/75 | 0/77 | 0/4 |
| Ankle fractureInjury, poisoning and procedural complications | 0/9 | 0/17 | 0/17 | 2/77 | 1/75 | 0/77 | 0/4 |
| Acute respiratory failureRespiratory, thoracic and mediastinal disorders | 0/9 | 0/17 | 0/17 | 2/77 | 0/75 | 0/77 | 0/4 |
| Event | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Part C: PD Recovery and Safety Follow-Up |
|---|---|---|---|---|---|---|---|
| FallInjury, poisoning and procedural complications | 4/9 | 9/17 | 10/17 | 40/77 | 39/75 | 42/77 | 1/4 |
| HeadacheNervous system disorders | 0/9 | 8/17 | 6/17 | 9/77 | 19/75 | 16/77 | 0/4 |
| COVID-19Infections and infestations | 1/9 | 6/17 | 5/17 | 8/77 | 9/75 | 11/77 | 0/4 |
| ChillsGeneral disorders | 0/9 | 3/17 | 5/17 | 3/77 | 18/75 | 25/77 | 0/4 |
| ArthralgiaMusculoskeletal and connective tissue disorders | 2/9 | 5/17 | 4/17 | 18/77 | 15/75 | 15/77 | 0/4 |
| ContusionInjury, poisoning and procedural complications | 2/9 | 1/17 | 2/17 | 11/77 | 13/75 | 12/77 | 1/4 |
| Skin abrasionInjury, poisoning and procedural complications | 2/9 | 0/17 | 1/17 | 11/77 | 4/75 | 9/77 | 1/4 |
| Limb injuryInjury, poisoning and procedural complications | 0/9 | 0/17 | 0/17 | 2/77 | 3/75 | 4/77 | 1/4 |
| Bone contusionInjury, poisoning and procedural complications | 0/9 | 0/17 | 0/17 | 1/77 | 0/75 | 2/77 | 1/4 |
| Joint injuryInjury, poisoning and procedural complications | 0/9 | 0/17 | 0/17 | 0/77 | 1/75 | 1/77 | 1/4 |
Safety Analysis Set comprised of all participants who were randomized and received at least one dose of study treatment.
| Age, Continuous(years) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Total |
|---|---|---|---|---|---|---|---|
| Mean | 68.6 ± 10.48 | 65.2 ± 7.04 | 68.6 ± 6.32 | 68.5 ± 7.31 | 68.5 ± 6.83 | 67.7 ± 9.17 | 68.1 ± 7.78 |
| Sex: Female, Male(Participants) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Total |
|---|---|---|---|---|---|---|---|
| Female | 4 | 4 | 6 | 22 | 27 | 23 | 86 |
| Male | 5 | 13 | 11 | 55 | 48 | 54 | 186 |
| Race/Ethnicity, Customized(Participants) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Total |
|---|---|---|---|---|---|---|---|
| Asian | 0 | 0 | 0 | 2 | 2 | 1 | 5 |
| Black or African American | 0 | 1 | 1 | 1 | 2 | 2 | 7 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 | 1 | 1 |
| White | 9 | 16 | 15 | 64 | 70 | 69 | 243 |
| Multiple | 0 | 0 | 0 | 1 | 0 | 2 | 3 |
| Other | 0 | 0 | 1 | 1 | 0 | 0 | 2 |
| Unknown | 0 | 0 | 0 | 2 | 0 | 0 | 2 |
| Missing | 0 | 0 | 0 | 6 | 1 | 2 | 9 |
| Race/Ethnicity, Customized(Participants) | Part A: Placebo | Part A: Ulviprubart 0.5 mg/kg | Part A: Ulviprubart 2.0 mg/kg | Part B: Placebo | Part B: Ulviprubart 0.5 mg/kg | Part B: Ulviprubart 2.0 mg/kg | Total |
|---|---|---|---|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 1 | 1 | 1 | 2 | 5 |
| Not Hispanic or Latino | 9 | 17 | 16 | 72 | 73 | 71 | 258 |
| Unknown | 0 | 0 | 0 | 0 | 1 | 0 | 1 |
| Not Reported | 0 | 0 | 0 | 4 | 0 | 4 | 8 |
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