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Rituximab for Treatment of Systemic Sclerosis-Associated Pulmonary Arterial Hypertension (SSc-PAH)

A Randomized, Double-Blind, Placebo-Controlled, Phase II Multicenter Trial of a Monoclonal Antibody to CD20 (Rituximab) for the Treatment of Systemic Sclerosis-Associated Pulmonary Arterial Hypertension (SSc-PAH)

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01086540
Enrollment
57
Registered
2010-03-15
Start date
2011-06-24
Completion date
2019-12-15
Last updated
2023-02-21

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

Conditions

Systemic Sclerosis-Associated PAH

Keywords

Pulmonary Arterial Hypertension (PAH), Autoimmune Disease, Systemic Scleroderma

Brief summary

Systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) is a serious, life-threatening manifestation of systemic sclerosis (SSc), an autoimmune disease of the connective tissue characterized by scarring (fibrosis) and atrophy of the skin, joints and tendons, skeletal muscles, and internal organs, and immunological disturbances. One-year survival for patients with SSc-PAH ranges from 50-81%. There is currently no cure for SSc-PAH and treatment is limited to vasodilator therapy used in all forms of PAH. In recent studies, immunotherapy was shown to be effective in treating SSc-interstitial lung disease, another serious, life-threatening manifestation of SSc. In addition, there are compelling pre-clinical data and anecdotal clinical reports that suggest modulation of the immune system may be an effective strategy for treating SSc-PAH. To test this approach, this trial will determine if rituximab, an immunotherapy, has a marked beneficial effect on clinical disease progression, with minimal toxicity, in patients with SSc-PAH when compared to placebo.

Detailed description

This prospective, double-blind, placebo-controlled, multi-center, randomized trial will evaluate the effect of rituximab on disease progression in subjects with SSc-PAH receiving concurrent stable-dose standard medical therapy with a prostanoid, endothelin receptor antagonist, and/or phosphodiesterase 5 (PDE-5) inhibitor. The study will focus on assessment of clinical response and safety measures longitudinally. In addition, the effects of treatment with rituximab on the underlying immune mechanisms associated with B-cell dysregulation and pathogenic autoantibody response in this disease will be investigated. 1000 mg of rituximab or placebo will be administered as two IV infusions given two weeks apart. Clinical assessments and sample collection will occur at monthly visits through Week 48. If a participant has not recovered B cells by Week 48, B cell studies will be conducted quarterly until reconstitution is documented or for 2 years after initial treatment. This trial will include a sub-study, entitled Right Ventricular Response to Rituximab in Systemic Sclerosis-Associated Pulmonary Arterial Hypertension - A Magnetic Resonance Imaging Sub-study (RESTORE Sub-study). The objective of the RESTORE sub-study is to evaluate the therapeutic effect of rituximab on the right ventricle of patients with SSc-PAH. Changes in right ventricular end diastolic volume index (RVEDVI) and stroke volume (SV) determined by cardiac MRI will be used as surrogates of right ventricle function and prognosis. Enrollment for the RESTORE sub-study will parallel that of main trial. Twenty patients from each treatment arm, distributed among all participating sites, will be recruited for this sub-study. Each patient will be studied at baseline (i.e. prior to initiation of study drug) and after 24 weeks or at time of discontinuation. In addition to the data collection and testing specified in the main trial, participants in RESTORE will undergo comprehensive cardiac MRI evaluation. All main trial study inclusion and exclusion criteria apply, as well as additional exclusion criteria that pertain only to the RESTORE sub-study: 1) known hypersensitivity to Gadolinium; 2) inability to tolerate or cooperate with MRI; 3) morbid obesity; and 4) presence of metallic objects or pacemakers.

Interventions

BIOLOGICALRituximab

Participants receive rituximab intravenous (IV) infusions, 1000 mg each, 14 days apart (Day 0 and Week 2). Rituximab is supplied as a sterile, clear, colorless, preservative-free liquid concentrate for intravenous (IV) administration in either 100 mg (10 mL) or 500 mg (50 mL) single-use vials, which must be diluted before administration Standard rituximab pre-medications will be provided in preparation for the rituximab infusions.

OTHERPlacebo

Participants receive placebo intravenous (IV) infusions 14 days apart (Day 0 and Week 2). Standard pre-medications will be provided in preparation for the infusions.

DIAGNOSTIC_TESTCMRI

Up to 20 participants from each treatment arm will be assessed by CMRI at Baseline and at Week 24.

DRUGprednisone

Prednisone dose of 40 mg (or equivalent) by mouth administered the night before and the morning of each study drug infusion.

DRUGmethylprednisolone

Methylprednisolone (or equivalent corticosteroid) administered intravenously 30 minutes prior to each study drug infusion.

DRUGdiphenhydramine

Diphenhydramine 50 mg (or equivalent) administered by mouth approximately thirty to sixty minutes prior to each study drug infusion. Dose may be repeated every four hours, as needed.

DRUGacetaminophen

Acetaminophen 650 mg (or equivalent) administered by mouth approximately thirty to sixty minutes prior to each study drug infusion. Dose may be repeated every four hours, as needed.

Sponsors

Autoimmunity Centers of Excellence
CollaboratorOTHER
Rho Federal Systems Division, Inc.
CollaboratorINDUSTRY
National Institute of Allergy and Infectious Diseases (NIAID)
Lead SponsorNIH

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

* Subject has provided written informed consent. * Clinical diagnosis of systemic sclerosis (either limited or diffuse cutaneous disease). * Diagnosis of SSc-PAH within the past 5 years, with a mean pulmonary arterial pressure of ≥ 25 mmHg at entry. * Mean Pulmonary Vascular Resistance (PVR) of \> 3 Wood units. * Screening 6-minute Walking Distance (6MWD) of at least 100 meters. * New York Heart Association (NYHA) Functional Class II, III, or IV. * Subject must be able to maintain O2 saturation ≥ 90% at rest (with or without oxygen); --Oxygen use is permitted. * Subject must be vaccinated with the pneumococcal vaccine at least one month prior to initiation of therapy, unless subject was vaccinated within 5 years of study entry. * Subject must have been treated with background medical therapy for PAH (prostanoid, endothelin receptor antagonist, PDE-5 inhibitor, and/or guanylate cyclase stimulators) for a minimum of 8 weeks and have been on stable dose medical therapy for at least 4 weeks prior to randomization with no expectation of change for 24 weeks after randomization.

Exclusion criteria

* Documented PAH for greater than 5 years at the time of randomization defined as: * Measurement of a mean Pulmonary Artery Pressure (PAP) \> 25 mmHg by right heart catheterization at least 5 years previously, OR * Treatment with targeted background PAH therapy for \> 5 years. * Pulmonary Capillary Wedge Pressure \> 15 mmHg or Left Ventricular End Diastolic Pressure \> 15 mmHg. * Persistent hypotension with Systolic Blood Pressure (SBP) \< 90 mmHg. * Treatment with cyclophosphamide within 4 weeks of randomization. * Treatment with immunocompromising biologic agents within 4 weeks prior to treatment initiation or treatment with infliximab within 8 weeks prior to treatment initiation. * If being treated with a non-biologic immunosuppressive or immunomodulating drug, changes in dosage within 4 weeks prior to randomization. Subjects taking prednisone or equivalent corticosteroid \> 10mg daily are excluded. * Previous exposure to any lymphocyte or B cell depleting agent. * PAH for any reason other than SSc. * History of coronary artery disease, significant ventricular tachy-arrhythmia, stent placement, coronary artery bypass surgery, and/or myocardial infarction. * Moderate or severe interstitial lung disease. * Chronic infections. * Positive serology for infection with hepatitis B or C. * A deep space infection within the past 2 years. * Evidence of active infection within 2 weeks of randomization * Presence of a positive tuberculosis (TB) skin test (e.g., PPD test) or positive QuantiFERON®-TB blood test, an indeterminate QuantiFERON®-TB blood test, or latent tuberculosis (TB). * Significant renal insufficiency. * Active, untreated SSc renal crisis at the time of enrollment. * Recent administration of a live vaccine (\< 8 weeks) or any other immunization within 4 weeks of treatment. * History of anaphylaxis or Immunoglobulin E (IgE) -mediated hypersensitivity to murine proteins or any component of rituximab. * Pregnancy. * Lactation. * History of malignancy within the last 5 years, except for resected basal or squamous cell carcinoma, treated cervical dysplasia, or treated in situ cervical cancer Grade I. * A woman of childbearing potential who is unwilling to use a medically acceptable form of birth control * History of non-compliance with other medical therapies. * History of alcohol or drug abuse within 1 year of randomization. * Receipt of any investigational drug or device within 4 weeks before the Screening Visit, with the exception of investigational prostanoids, endothelin receptor antagonists, and PDE-5 inhibitors, and guanylate cyclase stimulators. * Recipient of lung transplant. * Laboratory parameters at the screening visit showing any of the following abnormal results: Transaminases \> 2x the upper limit of normal (ULN) and/or bilirubin \> 2x ULN; Absolute neutrophil count \< 1,500/mm\^3; Platelet count \< 100,000/mm\^3; Hemoglobin \< 9 g/dL. * Concurrent treatment in a clinical research study using a non-FDA approved agent with the exception of an open-label study/study extension of investigational prostanoids, endothelin receptor antagonists, and PDE-5 inhibitors, and guanylate cyclase stimulators, provided the open-label investigational drug will be available and dose will remain stable through the trial's primary outcome time point of 24 weeks after randomization in this study, ASC01 (NCT01086540). * Any condition or treatment, which in the opinion of the investigator, places the subject at unacceptable risk as a participant in the trial.

Design outcomes

Primary

MeasureTime frameDescription
Change From Baseline in Distance Walked During a Six Minute Walk TestBaseline (Pre Treatment Initiation) to Week 24The six minute walk test measures the distance a participant is able to walk over a total of six minutes on a hard, flat surface. The goal is for the participant to walk as far as possible in six minutes. The participant is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The total distance walked, in meters, was recorded for each participant. Longer distances indicate better outcomes.

Secondary

MeasureTime frameDescription
Change From Baseline in Distance Walked During a Six Minute Walk Test at Week 24 and Week 48Baseline (Pre Treatment Initiation) to Week 24 and Week 48The six minute walk test measures the distance a participant is able to walk over a total of six minutes on a hard, flat surface. The goal is for the participant to walk as far as possible in six minutes. The participant is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The total distance walked, in meters, was recorded for each participant. Longer distances indicate better outcomes.
Time to Clinical WorseningBaseline (Pre Treatment Initiation) to Week 48Assessment of time to clinical worsening, censored at Week 48, defined as the first occurrence of any of the following: * death, * hospitalization for Systemic Sclerosis-Associated Pulmonary Arterial Hypertension (SSc-PAH), * lung transplantation, * atrial septostomy, * addition of other Pulmonary Arterial Hypertension (PAH) therapeutic agents, or * worsening of the six minute walk distance by \> 20% and an increase in New York Heart Association functional class. Time to clinical worsening was defined as the first date that met any of the above criteria and was calculated in study days as: date of first event minus (-) date of treatment randomization. If a participant did not experience any of the referenced events by Week 48 or, if the date of death was after the 48 week follow-up period, time to clinical worsening was equal to the participant's duration of follow-up in the study.
Time to the Change or Addition of New Pulmonary Arterial Hypertension (PAH) Therapeutic MedicationsBaseline (Pre Treatment Initiation) to Week 48Per protocol, from the time of study entry, participants were to remain on background PAH medical therapy with either a single agent or a combination of prostanoid, endothelin receptor antagonist, PDE-5 inhibitor, and/or guanylate cyclase stimulators as per the entry criteria. Doses should have remained stable through the Week 24 primary outcome/endpoint visit. If a dose of a background PAH medication was changed or a new PAH medication was added during the course of the trial, the date of the first dose change or additional medication was recorded. Time to the addition or modification of PAH medications was defined in study days as: date of the first time a PAH medication was modified or added minus (-) date of randomization.
Change From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Mental Component Summary ScoreBaseline (Pre Treatment Initiation) to Week 24 and Week 48The SF-36 measures health-related quality of life. It has 36 items and 2 component scores, the Physical Component Score and the Mental Component Score. The SF-36 Mental Health component summary score is comprised of the Vitality Scale, the Social Functioning Scale, the Role-Emotional Scale, and the Mental Health Scale. It is scaled from 0 to 100 with a score of 0 equivalent to maximum disability and a score of 100 is equivalent to no disability. A negative value indicates a decrease in quality of life from Baseline.
Change From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Physical Component Summary ScoreBaseline (Pre Treatment Initiation) to Week 48The SF-36 measures health-related quality of life. It has 36 items and 2 component scores, the Physical Component Score and the Mental Component Score. The SF-36 Physical component summary score is comprised of the Physical Functioning Scale, the Role-Physical Scale, the Bodily Pain Scale, and the General Health Scale. It is scaled from 0 to 100 with a score of 0 equivalent to maximum disability and a score of 100 is equivalent to no disability. A negative value indicates a decrease in quality of life from Baseline.
Change in Quality of Life as Measured by the Disability Index of the Scleroderma Health Assessment Questionnaire (HAQ-DI)Baseline (Pre Treatment Initiation) to Week 24 and Week 48The HAQ-DI is a self-reported questionnaire of functionality that includes questions in 8 domains (dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities) and addresses scleroderma related manifestations that contribute to disability. The final score ranges from 0 to 3, where a higher HAQ-DI score indicates a worse outcome.
Number of New Digital UlcersBaseline (Pre Treatment Initiation) to Week 24 and Week 48The total number of digital ulcers present on the dorsal and palmar surfaces for both the left and right fingers were captured at the Baseline study visit. The number of new digital ulcers since the last study visit (including any ulcers that had appeared and healed since the last study visit) on the dorsal and palmar surfaces for both the left and right fingers were captured at the post-Baseline study visits. The total number of digital ulcers on both hands was summed from the number present on the dorsal and palmar surfaces for both the left and right fingers.
Change in Severity of Raynaud's PhenomenonBaseline (Pre Treatment Initiation) to Week 24 and Week 48Severity of Raynaud's phenomenon was measured by a Visual Analog Scale (VAS) of the Scleroderma Health Assessment Questionnaire (SHAQ). The SHAQ VAS includes a question asking, In the past week, how much has your Raynaud's Phenomenon interfered with your activities? Participants were asked to place a mark on a 15 cm line, scaled from 0 (does not interfere) to 100 (very severe limitation), to describe the severity of their Raynaud's phenomenon in the past week. The distance from the left edge of the line to the vertical line placed by the participant was measured in centimeters; VAS scores were converted to a 0 to 100 scale.
Change From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization at Week 24Baseline (Pre Treatment Initiation) to Week 24During a right heart catheterization, a catheter is guided to the right side of the heart and then into the pulmonary artery; blood flow through the heart is observed and is used to measure pressures in a participant's heart and lungs. The calculation of Pulmonary Vascular Resistance (PVR) is measured in Woods Units. Change is derived by measuring the difference between Baseline and Week 24 PVR (Week 24 minus Baseline). Higher PVR values indicate worse disease status.
Oxygen Saturation Levels at Week 24 and Week 48Week 24 , Week 48Oxygen saturation is the amount of oxygen that is in your bloodstream and is measured as the percentage of blood hemoglobin that is carrying oxygen. Normal oxygen saturation levels are considered to be 95-100 percent; low oxygen saturation values indicate worse disease. Room air oxygen saturation by pulse oximetry and/or amount of supplemental oxygen used, if saturation \<90%, were recorded.
Percent Change From Baseline in Pulmonary Vascular Resistance Measured by Right Heart CatheterizationBaseline (Pre Treatment Initiation) to Week 24During a right heart catheterization, a catheter is guided to the right side of the heart and then into the pulmonary artery; blood flow through the heart is observed and is used to measure pressures in a participant's heart and lungs. Pulmonary vascular resistance (PVR) is measured in Woods Units. Higher PVR values indicate worse disease status. Change in PVR is determined by Baseline value minus (-) Week 24 value.
Number of Infusion-Related ToxicitiesDay 0 (Treatment Randomization) to Week 48The number of Grade 3, 4, and 5 Adverse Events (AEs), which were defined as possibly, probably, or definitely related to rituximab or placebo infusion. This study graded the severity of adverse events according to the National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE), Version 4.0.
Number of Grade 3 or Higher Adverse Events (AEs) Through Week 48Baseline (Pre Treatment Initiation) to Week 48Total number of Grade 3, 4, and 5 AEs. Ref: National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE), Version 4.0.
Number of Infection-Related Adverse Events (AEs) Through Week 48Day 0 (Treatment Randomization) to Week 48Number of adverse events classified as infections. Reference: National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE), Version 4.0.
Treatment-Related Mortality: From Treatment Initiation to Week 48Day 0 (Treatment Randomization) to Week 48Death occurring after randomization and ≤ Week 48, and possibly, probably, or definitely resulting from assigned study treatment.
All-Cause Mortality: From Treatment Initiation to Week 48Day 0 (Treatment Randomization) to Week 48Death from any cause occurring after randomization and ≤ Week 48.
All-Cause Mortality: From Treatment Initiation to Week 104Day 0 (Treatment Randomization) to Week 104Death from any cause occurring after randomization and ≤ Week 104.
Change in Carbon Monoxide Diffusing Capacity (DLCO)Baseline (Pre Treatment Initiation) to Week 24 and Week 48Carbon Monoxide Diffusing Capacity (DLCO) is a measure of lung function. Predicted values for DLCO were computed according to the Global Lung Function Initiative (GLI) all-age reference values and corrected for hemoglobin. Lower DLCO values indicate worse disease activity. DLCO (Diffusing Capacity of the Lungs for Carbon Monoxide)

Countries

United States

Participant flow

Recruitment details

Twenty-six study sites in the US were activated. Of these, 19 sites screened a total of 108 participants. Fifty-seven participants were randomized and study results summarized.

Participants by arm

ArmCount
Rituximab
Rituximab (a monoclonal antibody to CD20) was administered as two IV infusions, 1000 mg each, given two weeks apart at Day 0 and Week 2. Participants were pre-treated with corticosteroids, diphenhydramine, and acetaminophen. The appearance of the packaging and solutions used to administer rituximab/placebo was identical in both study arms.
29
Placebo
Placebo was administered as two IV infusions, given two weeks apart at Day 0 and Week 2. Participants were pre-treated with corticosteroids, diphenhydramine, and acetaminophen. The appearance of the packaging and solutions used to administer rituximab/placebo was identical in both study arms.
28
Total57

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyAddition of new therapy for PAH10
Overall StudyDeath31
Overall StudyPhysician Decision21

Baseline characteristics

CharacteristicRituximabTotalPlacebo
Age, Continuous57.3 years
STANDARD_DEVIATION 8.9
58.2 years
STANDARD_DEVIATION 9.1
59.1 years
STANDARD_DEVIATION 9.4
Ethnicity (NIH/OMB)
Hispanic or Latino
3 Participants5 Participants2 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
26 Participants52 Participants26 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants1 Participants1 Participants
Race (NIH/OMB)
Black or African American
4 Participants5 Participants1 Participants
Race (NIH/OMB)
More than one race
0 Participants2 Participants2 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants1 Participants0 Participants
Race (NIH/OMB)
White
24 Participants48 Participants24 Participants
Region of Enrollment
United States
29 Participants57 Participants28 Participants
Sex: Female, Male
Female
25 Participants52 Participants27 Participants
Sex: Female, Male
Male
4 Participants5 Participants1 Participants
Six Minute Walk Test Distance (Meters)338.7 Meters
STANDARD_DEVIATION 103.3
331.2 Meters
STANDARD_DEVIATION 99.7
323.4 Meters
STANDARD_DEVIATION 97.1

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
8 / 295 / 28
other
Total, other adverse events
28 / 2924 / 28
serious
Total, serious adverse events
14 / 299 / 28

Outcome results

Primary

Change From Baseline in Distance Walked During a Six Minute Walk Test

The six minute walk test measures the distance a participant is able to walk over a total of six minutes on a hard, flat surface. The goal is for the participant to walk as far as possible in six minutes. The participant is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The total distance walked, in meters, was recorded for each participant. Longer distances indicate better outcomes.

Time frame: Baseline (Pre Treatment Initiation) to Week 24

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange From Baseline in Distance Walked During a Six Minute Walk Test23.6 MetersStandard Error 11.1
PlaceboChange From Baseline in Distance Walked During a Six Minute Walk Test0.5 MetersStandard Error 9.7
Comparison: The null hypothesis was that the mean change in 6MWD between baseline and Week 24 does not differ between rituximab and placebo. A repeated measures random effect model was fit to model the distance walked as a function of treatment, visit week, a treatment by visit week interaction, and a quadratic visit term. A random slope and intercept were fit for each participant using a separate unstructured covariance matrix for each treatment group. The model included all available data up to Week 24.p-value: 0.12Mixed Models Analysis
Secondary

All-Cause Mortality: From Treatment Initiation to Week 104

Death from any cause occurring after randomization and ≤ Week 104.

Time frame: Day 0 (Treatment Randomization) to Week 104

Population: The Safety population included all participants for whom study treatment was initiated.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
RituximabAll-Cause Mortality: From Treatment Initiation to Week 1048 Participants
PlaceboAll-Cause Mortality: From Treatment Initiation to Week 1045 Participants
Comparison: Kaplan-Meier curves for time to all-cause mortality were compared using a log-rank test.p-value: 0.35Log Rank
Secondary

All-Cause Mortality: From Treatment Initiation to Week 48

Death from any cause occurring after randomization and ≤ Week 48.

Time frame: Day 0 (Treatment Randomization) to Week 48

Population: The Safety population included all participants for whom study treatment was initiated.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
RituximabAll-Cause Mortality: From Treatment Initiation to Week 484 Participants
PlaceboAll-Cause Mortality: From Treatment Initiation to Week 481 Participants
Comparison: Kaplan-Meier curves for time to all-cause mortality were compared using a log-rank test.p-value: 0.17Log Rank
Secondary

Change From Baseline in Distance Walked During a Six Minute Walk Test at Week 24 and Week 48

The six minute walk test measures the distance a participant is able to walk over a total of six minutes on a hard, flat surface. The goal is for the participant to walk as far as possible in six minutes. The participant is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The total distance walked, in meters, was recorded for each participant. Longer distances indicate better outcomes.

Time frame: Baseline (Pre Treatment Initiation) to Week 24 and Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange From Baseline in Distance Walked During a Six Minute Walk Test at Week 24 and Week 48Change from Baseline to Week 2425.5 MetersStandard Error 8.8
RituximabChange From Baseline in Distance Walked During a Six Minute Walk Test at Week 24 and Week 48Change from Baseline to Week 489.5 MetersStandard Error 12.4
PlaceboChange From Baseline in Distance Walked During a Six Minute Walk Test at Week 24 and Week 48Change from Baseline to Week 240.4 MetersStandard Error 7.4
PlaceboChange From Baseline in Distance Walked During a Six Minute Walk Test at Week 24 and Week 48Change from Baseline to Week 48-7.0 MetersStandard Error 8.6
Comparison: A repeated measures random effect model was fit to model the distance walked as a function of treatment, visit week, a treatment by visit week interaction, and a quadratic visit term. A random slope and intercept were fit for each participant using a separate unstructured covariance matrix for each treatment group. The model included all available data up to Week 48.p-value: 0.28Mixed Models Analysis
Comparison: A repeated measures random effect model was fit to model the distance walked as a function of treatment, visit week, a treatment by visit week interaction, and a quadratic visit term. A random slope and intercept were fit for each participant using a separate unstructured covariance matrix for each treatment group. The model included all available data up to Week 48.p-value: 0.031Mixed Models Analysis
Secondary

Change From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization at Week 24

During a right heart catheterization, a catheter is guided to the right side of the heart and then into the pulmonary artery; blood flow through the heart is observed and is used to measure pressures in a participant's heart and lungs. The calculation of Pulmonary Vascular Resistance (PVR) is measured in Woods Units. Change is derived by measuring the difference between Baseline and Week 24 PVR (Week 24 minus Baseline). Higher PVR values indicate worse disease status.

Time frame: Baseline (Pre Treatment Initiation) to Week 24

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization at Week 24-0.5 Woods UnitsStandard Error 0.36
PlaceboChange From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization at Week 240.1 Woods UnitsStandard Error 0.61
Comparison: A repeated measures mixed model was fit with PVR as the outcome and treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.42Mixed Models Analysis
Secondary

Change From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Mental Component Summary Score

The SF-36 measures health-related quality of life. It has 36 items and 2 component scores, the Physical Component Score and the Mental Component Score. The SF-36 Mental Health component summary score is comprised of the Vitality Scale, the Social Functioning Scale, the Role-Emotional Scale, and the Mental Health Scale. It is scaled from 0 to 100 with a score of 0 equivalent to maximum disability and a score of 100 is equivalent to no disability. A negative value indicates a decrease in quality of life from Baseline.

Time frame: Baseline (Pre Treatment Initiation) to Week 24 and Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Mental Component Summary ScoreChange from Baseline to Week 240.1 Units on a ScaleStandard Error 0.9
RituximabChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Mental Component Summary ScoreChange from Baseline to Week 480.2 Units on a ScaleStandard Error 1.8
PlaceboChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Mental Component Summary ScoreChange from Baseline to Week 240.4 Units on a ScaleStandard Error 1
PlaceboChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Mental Component Summary ScoreChange from Baseline to Week 480.9 Units on a ScaleStandard Error 1.9
Comparison: A repeated measures random effect model was fit with the mental component score as the outcome, and treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.81Mixed Models Analysis
Secondary

Change From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Physical Component Summary Score

The SF-36 measures health-related quality of life. It has 36 items and 2 component scores, the Physical Component Score and the Mental Component Score. The SF-36 Physical component summary score is comprised of the Physical Functioning Scale, the Role-Physical Scale, the Bodily Pain Scale, and the General Health Scale. It is scaled from 0 to 100 with a score of 0 equivalent to maximum disability and a score of 100 is equivalent to no disability. A negative value indicates a decrease in quality of life from Baseline.

Time frame: Baseline (Pre Treatment Initiation) to Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Physical Component Summary ScoreChange from Baseline to Week 240.6 Units on a ScaleStandard Error 0.8
RituximabChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Physical Component Summary ScoreChange from Baseline to Week 481.3 Units on a ScaleStandard Error 1.5
PlaceboChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Physical Component Summary ScoreChange from Baseline to Week 241.7 Units on a ScaleStandard Error 0.7
PlaceboChange From Baseline in Quality of Life as Measured by the Short Form Health Survey (SF-36): Physical Component Summary ScoreChange from Baseline to Week 483.5 Units on a ScaleStandard Error 1.5
Comparison: A repeated measures random effect model was fit with the physical component score as the outcome, and treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.3Mixed Models Analysis
Secondary

Change in Carbon Monoxide Diffusing Capacity (DLCO)

Carbon Monoxide Diffusing Capacity (DLCO) is a measure of lung function. Predicted values for DLCO were computed according to the Global Lung Function Initiative (GLI) all-age reference values and corrected for hemoglobin. Lower DLCO values indicate worse disease activity. DLCO (Diffusing Capacity of the Lungs for Carbon Monoxide)

Time frame: Baseline (Pre Treatment Initiation) to Week 24 and Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange in Carbon Monoxide Diffusing Capacity (DLCO)Change from Baseline to Week 24-0.3 Percent Predicted ValueStandard Error 1.03
RituximabChange in Carbon Monoxide Diffusing Capacity (DLCO)Change from Baseline to Week 48-0.5 Percent Predicted ValueStandard Error 2.06
PlaceboChange in Carbon Monoxide Diffusing Capacity (DLCO)Change from Baseline to Week 240.4 Percent Predicted ValueStandard Error 0.95
PlaceboChange in Carbon Monoxide Diffusing Capacity (DLCO)Change from Baseline to Week 480.7 Percent Predicted ValueStandard Error 1.89
Comparison: A repeated measures random effect model was fit with DLCO as the outcome, and treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.65Mixed Models Analysis
Secondary

Change in Quality of Life as Measured by the Disability Index of the Scleroderma Health Assessment Questionnaire (HAQ-DI)

The HAQ-DI is a self-reported questionnaire of functionality that includes questions in 8 domains (dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities) and addresses scleroderma related manifestations that contribute to disability. The final score ranges from 0 to 3, where a higher HAQ-DI score indicates a worse outcome.

Time frame: Baseline (Pre Treatment Initiation) to Week 24 and Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange in Quality of Life as Measured by the Disability Index of the Scleroderma Health Assessment Questionnaire (HAQ-DI)Change from Baseline to Week 240.0 Units on a ScaleStandard Error 0.05
RituximabChange in Quality of Life as Measured by the Disability Index of the Scleroderma Health Assessment Questionnaire (HAQ-DI)Change from Baseline to Week 480.0 Units on a ScaleStandard Error 0.09
PlaceboChange in Quality of Life as Measured by the Disability Index of the Scleroderma Health Assessment Questionnaire (HAQ-DI)Change from Baseline to Week 240.0 Units on a ScaleStandard Error 0.02
PlaceboChange in Quality of Life as Measured by the Disability Index of the Scleroderma Health Assessment Questionnaire (HAQ-DI)Change from Baseline to Week 480.0 Units on a ScaleStandard Error 0.05
Comparison: A repeated measures random effect model was fit with HAQ-DI as the outcome, and treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.58Mixed Models Analysis
Secondary

Change in Severity of Raynaud's Phenomenon

Severity of Raynaud's phenomenon was measured by a Visual Analog Scale (VAS) of the Scleroderma Health Assessment Questionnaire (SHAQ). The SHAQ VAS includes a question asking, In the past week, how much has your Raynaud's Phenomenon interfered with your activities? Participants were asked to place a mark on a 15 cm line, scaled from 0 (does not interfere) to 100 (very severe limitation), to describe the severity of their Raynaud's phenomenon in the past week. The distance from the left edge of the line to the vertical line placed by the participant was measured in centimeters; VAS scores were converted to a 0 to 100 scale.

Time frame: Baseline (Pre Treatment Initiation) to Week 24 and Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
RituximabChange in Severity of Raynaud's PhenomenonChange from Baseline to Week 24-2.2 Score on a ScaleStandard Error 1.8
RituximabChange in Severity of Raynaud's PhenomenonChange from Baseline to Week 48-4.4 Score on a ScaleStandard Error 3.6
PlaceboChange in Severity of Raynaud's PhenomenonChange from Baseline to Week 480.1 Score on a ScaleStandard Error 4.4
PlaceboChange in Severity of Raynaud's PhenomenonChange from Baseline to Week 240.1 Score on a ScaleStandard Error 2.2
Comparison: A repeated measures random effect model was fit with severity of Raynaud's (0 to 100) as the outcome, and treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.43Mixed Models Analysis
Secondary

Number of Grade 3 or Higher Adverse Events (AEs) Through Week 48

Total number of Grade 3, 4, and 5 AEs. Ref: National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE), Version 4.0.

Time frame: Baseline (Pre Treatment Initiation) to Week 48

Population: The Safety population included all participants for whom study treatment was initiated.

ArmMeasureGroupValue (NUMBER)
RituximabNumber of Grade 3 or Higher Adverse Events (AEs) Through Week 48Grade 3 AEs28 Events
RituximabNumber of Grade 3 or Higher Adverse Events (AEs) Through Week 48Grade 4 AEs6 Events
RituximabNumber of Grade 3 or Higher Adverse Events (AEs) Through Week 48Grade 5 AEs3 Events
PlaceboNumber of Grade 3 or Higher Adverse Events (AEs) Through Week 48Grade 3 AEs19 Events
PlaceboNumber of Grade 3 or Higher Adverse Events (AEs) Through Week 48Grade 4 AEs2 Events
PlaceboNumber of Grade 3 or Higher Adverse Events (AEs) Through Week 48Grade 5 AEs1 Events
Secondary

Number of Infection-Related Adverse Events (AEs) Through Week 48

Number of adverse events classified as infections. Reference: National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE), Version 4.0.

Time frame: Day 0 (Treatment Randomization) to Week 48

Population: The Safety population included all participants for whom study treatment was initiated.

ArmMeasureValue (NUMBER)
RituximabNumber of Infection-Related Adverse Events (AEs) Through Week 4848 Events
PlaceboNumber of Infection-Related Adverse Events (AEs) Through Week 4844 Events
Secondary

Number of Infusion-Related Toxicities

The number of Grade 3, 4, and 5 Adverse Events (AEs), which were defined as possibly, probably, or definitely related to rituximab or placebo infusion. This study graded the severity of adverse events according to the National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE), Version 4.0.

Time frame: Day 0 (Treatment Randomization) to Week 48

Population: The Safety population included all participants for whom study treatment was initiated.

ArmMeasureGroupValue (NUMBER)
RituximabNumber of Infusion-Related ToxicitiesGrade 3 AEs15 Events
RituximabNumber of Infusion-Related ToxicitiesGrade 4 AEs3 Events
RituximabNumber of Infusion-Related ToxicitiesGrade 5 AEs0 Events
PlaceboNumber of Infusion-Related ToxicitiesGrade 3 AEs7 Events
PlaceboNumber of Infusion-Related ToxicitiesGrade 4 AEs0 Events
PlaceboNumber of Infusion-Related ToxicitiesGrade 5 AEs0 Events
Secondary

Number of New Digital Ulcers

The total number of digital ulcers present on the dorsal and palmar surfaces for both the left and right fingers were captured at the Baseline study visit. The number of new digital ulcers since the last study visit (including any ulcers that had appeared and healed since the last study visit) on the dorsal and palmar surfaces for both the left and right fingers were captured at the post-Baseline study visits. The total number of digital ulcers on both hands was summed from the number present on the dorsal and palmar surfaces for both the left and right fingers.

Time frame: Baseline (Pre Treatment Initiation) to Week 24 and Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (MEAN)Dispersion
RituximabNumber of New Digital UlcersNew Ulcers at Week 480.1 New UlcersStandard Deviation 0.29
RituximabNumber of New Digital UlcersTotal Ulcer Count at Baseline0.6 New UlcersStandard Deviation 2.04
RituximabNumber of New Digital UlcersNew Ulcers at Week 240.0 New UlcersStandard Deviation 0
PlaceboNumber of New Digital UlcersNew Ulcers at Week 240.1 New UlcersStandard Deviation 0.59
PlaceboNumber of New Digital UlcersNew Ulcers at Week 480.2 New UlcersStandard Deviation 0.63
PlaceboNumber of New Digital UlcersTotal Ulcer Count at Baseline0.4 New UlcersStandard Deviation 1.58
Comparison: A Poisson model was used to describe the rate of new digital ulcers (per week) as the outcome with treatment, number of digital ulcers at Baseline, and if the measurement was affected by changed or new PAH therapeutic agents as covariates.p-value: 0.47Regression, Linear
Secondary

Oxygen Saturation Levels at Week 24 and Week 48

Oxygen saturation is the amount of oxygen that is in your bloodstream and is measured as the percentage of blood hemoglobin that is carrying oxygen. Normal oxygen saturation levels are considered to be 95-100 percent; low oxygen saturation values indicate worse disease. Room air oxygen saturation by pulse oximetry and/or amount of supplemental oxygen used, if saturation \<90%, were recorded.

Time frame: Week 24 , Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated treatment. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureGroupValue (MEAN)Dispersion
RituximabOxygen Saturation Levels at Week 24 and Week 48O2 Sat Level: Week 2496.5 Percent Oxygen SaturationStandard Deviation 3.4
RituximabOxygen Saturation Levels at Week 24 and Week 48O2 Sat Level: Week 4897.7 Percent Oxygen SaturationStandard Deviation 2.5
PlaceboOxygen Saturation Levels at Week 24 and Week 48O2 Sat Level: Week 2496.1 Percent Oxygen SaturationStandard Deviation 3.9
PlaceboOxygen Saturation Levels at Week 24 and Week 48O2 Sat Level: Week 4896.2 Percent Oxygen SaturationStandard Deviation 4.6
Secondary

Percent Change From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization

During a right heart catheterization, a catheter is guided to the right side of the heart and then into the pulmonary artery; blood flow through the heart is observed and is used to measure pressures in a participant's heart and lungs. Pulmonary vascular resistance (PVR) is measured in Woods Units. Higher PVR values indicate worse disease status. Change in PVR is determined by Baseline value minus (-) Week 24 value.

Time frame: Baseline (Pre Treatment Initiation) to Week 24

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated treatment. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
RituximabPercent Change From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization-4.6 Percent ChangeStandard Error 5.5
PlaceboPercent Change From Baseline in Pulmonary Vascular Resistance Measured by Right Heart Catheterization3.2 Percent ChangeStandard Error 7.9
Comparison: A repeated measures mixed model was fit with percent change in PVR as the outcome and baseline PVR, treatment, visit week (actual observed week), and their interaction as predictors. Random intercepts and slopes were fit for each participant using an unstructured covariance structure for each treatment group.p-value: 0.42Mixed Models Analysis
Secondary

Time to Clinical Worsening

Assessment of time to clinical worsening, censored at Week 48, defined as the first occurrence of any of the following: * death, * hospitalization for Systemic Sclerosis-Associated Pulmonary Arterial Hypertension (SSc-PAH), * lung transplantation, * atrial septostomy, * addition of other Pulmonary Arterial Hypertension (PAH) therapeutic agents, or * worsening of the six minute walk distance by \> 20% and an increase in New York Heart Association functional class. Time to clinical worsening was defined as the first date that met any of the above criteria and was calculated in study days as: date of first event minus (-) date of treatment randomization. If a participant did not experience any of the referenced events by Week 48 or, if the date of death was after the 48 week follow-up period, time to clinical worsening was equal to the participant's duration of follow-up in the study.

Time frame: Baseline (Pre Treatment Initiation) to Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were included in the ITT population in the groups to which they were randomized.

ArmMeasureValue (MEAN)Dispersion
RituximabTime to Clinical Worsening21.2 WeeksStandard Deviation 14.2
PlaceboTime to Clinical Worsening26.2 WeeksStandard Deviation 4
Comparison: Kaplan-Meier curves for time to clinical worsening were compared using a log-rank test.p-value: 0.92Log Rank
Secondary

Time to the Change or Addition of New Pulmonary Arterial Hypertension (PAH) Therapeutic Medications

Per protocol, from the time of study entry, participants were to remain on background PAH medical therapy with either a single agent or a combination of prostanoid, endothelin receptor antagonist, PDE-5 inhibitor, and/or guanylate cyclase stimulators as per the entry criteria. Doses should have remained stable through the Week 24 primary outcome/endpoint visit. If a dose of a background PAH medication was changed or a new PAH medication was added during the course of the trial, the date of the first dose change or additional medication was recorded. Time to the addition or modification of PAH medications was defined in study days as: date of the first time a PAH medication was modified or added minus (-) date of randomization.

Time frame: Baseline (Pre Treatment Initiation) to Week 48

Population: The Modified Intent-to-Treat (ITT) population included all randomized participants who met entry criteria and initiated therapy. Participants who, for whatever reason, did not complete their assigned therapy were be included in the ITT population in the groups to which they were randomized.

ArmMeasureValue (MEAN)Dispersion
RituximabTime to the Change or Addition of New Pulmonary Arterial Hypertension (PAH) Therapeutic Medications21.2 WeeksStandard Deviation 14.4
PlaceboTime to the Change or Addition of New Pulmonary Arterial Hypertension (PAH) Therapeutic Medications26.7 WeeksStandard Deviation 3.9
Comparison: Kaplan-Meier curves for time to change or addition of PAH medications were compared using a log-rank test.p-value: 0.36Log Rank
Secondary

Treatment-Related Mortality: From Treatment Initiation to Week 48

Death occurring after randomization and ≤ Week 48, and possibly, probably, or definitely resulting from assigned study treatment.

Time frame: Day 0 (Treatment Randomization) to Week 48

Population: The Safety population included all participants for whom study treatment was initiated.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
RituximabTreatment-Related Mortality: From Treatment Initiation to Week 480 Participants
PlaceboTreatment-Related Mortality: From Treatment Initiation to Week 480 Participants

Source: ClinicalTrials.gov · Data processed: Feb 15, 2026