This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Phase 2 Study: An Open-Label, Randomized, Phase 2 Dose-Finding Study of Pacritinib in Patients With Primary Myelofibrosis, Post-Polycythemia Vera Myelofibrosis, or Post- Essential Thrombocythemia Myelofibrosis Previously Treated With Ruxolitinib (NCT04884191), a randomized phase 2 study. The primary outcome is Spleen Volume Reduction Response (≥ 35%).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04884191 |
| Phase | Phase 2 |
| Condition | Primary Myelofibrosis, Post-Polycythemia Vera Myelofibrosis, Post- Essential Thrombocythemia Myelofibrosis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 165 |
| Arms in the primary outcome | n/a |
| Lead sponsor | CTI BioPharma |
| Results posted | Yes |
2. Clinical Question
The study asks whether spleen-volume reduction responses differ across three pacritinib dose regimens in people with primary or secondary myelofibrosis who had previously received ruxolitinib. The registry describes the population as having a Dynamic International Prognostic Scoring System risk score from Intermediate-1 to High-Risk. The listed conditions are primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis.
Population
People with primary or secondary myelofibrosis previously treated with ruxolitinib, with the stated risk-score range and listed myelofibrosis conditions.
Intervention
Pacritinib at 100 mg once daily, 100 mg twice daily, or 200 mg twice daily.
Comparator
The other randomized pacritinib dose regimens. The registry record does not list a placebo or non-pacritinib comparator.
Primary question
How many participants achieve at least 35% spleen-volume reduction, measured by MRI or CT, from baseline to weeks 12 and 24 in the dose groups?
The endpoint is a participant count rather than a continuous measure of average spleen-volume change. The registry record does not report the response counts by dose or a statistical comparison among the regimens. It therefore establishes the question and the outcome definition, but does not allow a conclusion about which regimen had a higher response rate or how precisely the groups differed.
3. Trial Design
This was a randomized, open-label, parallel-group phase 2 dose-finding study sponsored by CTI BioPharma. The record describes three pacritinib regimens: 100 mg once daily, 100 mg twice daily, and 200 mg twice daily. Randomization assigns participants to treatment groups by chance; in general, this can help make groups comparable at the start, though it does not ensure that every characteristic is balanced. The record does not describe the randomization procedure or allocation concealment.
Open-label means the study was not masked: the masking entry is none. In general, awareness of treatment assignment can affect participant experience, clinical decisions, and outcome assessment. The primary outcome was based on imaging, but the record does not describe whether image readers were blinded to dose assignment or how imaging assessments were centrally reviewed.
The registry lists enrollment of 165. The recorded start date is 2017-07-31, the primary completion date is 2019-09-04, and the study status is completed. Its stated purpose was to support a pacritinib dosage selection decision by evaluating three dosages. This describes a dose-finding objective; it does not establish that a particular dose was selected or that any dose was superior.
The primary outcome concerns spleen-volume response from baseline to weeks 12 and 24. Secondary outcomes listed in the record include spleen length reduction, frequency of red blood cell or platelet transfusions, Eastern Cooperative Oncology Group performance status, and participants with adverse events. The record lists eight outcome measures overall, but does not report the details of all measures in the registry record for this analysis. Further details of eligibility criteria, treatment duration, dose modifications, concomitant care, and follow-up are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Pacritinib 100 mg QD | Pacritinib 100 mg BID | Pacritinib 200 mg BID |
|---|---|---|---|
| STARTED | 55 | 55 | 55 |
| COMPLETED | 52 | 55 | 54 |
| NOT COMPLETED | 3 | 0 | 1 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Pacritinib 100 mg QD | Pacritinib 100 mg BID | Pacritinib 200 mg BID | Total |
|---|---|---|---|---|---|
| Participants analysed | 52 | 55 | 54 | 161 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 16 | 11 | 16 | 43 |
| Age, Categorical: >=65 years | Participants | 36 | 44 | 38 | 118 |
| Age, Continuous | years | 69 (SD 8.8) | 68.9 (SD 6.9) | 68.1 (SD 8.76) | 68.7 (SD 8.14) |
| Sex: Female, Male: Female | Participants | 21 | 26 | 22 | 69 |
| Sex: Female, Male: Male | Participants | 31 | 29 | 32 | 92 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 1 | 1 |
| Race (NIH/OMB): Asian | Participants | 2 | 1 | 1 | 4 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 0 | 4 | 5 |
| Race (NIH/OMB): White | Participants | 44 | 47 | 48 | 139 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 5 | 7 | 0 | 12 |
| BMI | kg/m^2 | 25.1 (SD 3.79) | 27.2 (SD 4.11) | 26.4 (SD 5) | 26.3 (SD 4.4) |
| ECOG PS: 0 | participants | 11 | 14 | 17 | 42 |
| ECOG PS: 1 | participants | 32 | 29 | 29 | 90 |
| ECOG PS: 2 | participants | 9 | 12 | 8 | 29 |
6. Primary Endpoint
The registry lists the primary outcome as Spleen Volume Reduction Response (≥ 35%), measured over From Baseline to Weeks 12 and 24.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with at least 35% spleen-volume reduction from baseline, assessed at weeks 12 and 24. The description specifies measurement using magnetic resonance imaging, preferred, or computed tomography. It is a binary response definition at each assessment: a participant either meets the stated reduction threshold or does not. The outcome is reported as a count of participants, rather than as the amount of volume change for every participant.
In general, a threshold-based endpoint can make a clinical outcome easier to interpret as a responder count, while discarding information about changes that fall short of or exceed the threshold. Imaging provides a way to quantify spleen size, and spleen-volume response is used in myelofibrosis studies as an indicator of change in disease burden. That general rationale does not make the endpoint a complete measure of how a participant feels or functions.
The registry specifies two assessment times, weeks 12 and 24, so the endpoint is not one single time-point result. Its description does not state how missing or unevaluable scans were handled, whether a response had to be confirmed, or what analysis population was used. Most importantly for interpretation, response counts and a dose-group comparison are not reported in the registry record. The endpoint definition alone cannot establish the observed frequency of response.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a randomized comparison of three pacritinib dosing regimens, with spleen-volume reduction of at least 35% at weeks 12 and 24 as the primary outcome. It does not report the outcome counts by dose, an effect estimate comparing the groups, a confidence interval, or a significance test for the primary endpoint. The record lists zero analyses, and the primary outcome has several categories or time points and is not reduced to one comparison in the posted results. Consequently, no estimate of the relative or absolute difference in response can be interpreted from this record.
This distinction is important: an endpoint definition tells the reader what the investigators intended to measure, while a result requires observed data and an analysis. Without response counts or an estimate of uncertainty, it is not possible to say which regimen produced more responses, whether the groups were similar, or how precise any difference would be. No conclusion about efficacy follows from the design, enrollment, or planned assessment times alone.
The trial's dose-finding purpose also affects how its question should be read. It evaluates three active dose regimens to inform dose selection, rather than comparing pacritinib with no treatment or a different therapy. The registry record does not state a formal dose-selection rule or report a selected regimen. Even if response results were available, a decision about dose would ordinarily need to consider safety and other outcomes as well as the primary endpoint; this record does not report a formal combined decision analysis.
The safety information is presented separately as counts of participants affected by serious or other adverse events and as a list of serious event terms with percentages. These summaries describe events recorded in the groups, not proof that an event was caused by pacritinib. The registry record does not report the methods used to assess causality, exposure-adjusted event rates, or comparative safety estimates. Death counts are listed, but the record does not specify causes or attribute deaths to treatment.
Overall, the record supports a description of the study question, design, endpoint, and selected safety summaries. It does not provide a reported primary-outcome result from which to judge the size, direction, or precision of a dose-group difference. Any planning illustration based on an observed effect should be understood as a hypothetical design calculation, not as evidence of observed power or as a substitute for the unreported endpoint analysis.
9. Statistical Methods Explained
What does randomization contribute? In general, randomization allocates participants by chance rather than by a clinician's or participant's choice. It can reduce systematic differences in prognostic characteristics between groups on average, supporting a more credible comparison. It does not guarantee balance in a particular trial, especially across every characteristic, and it does not correct problems caused by missing outcomes or departures from assigned treatment. The registry record identifies the study as randomized and parallel, but the randomization sequence, stratification factors, and allocation concealment are not reported in the registry record.
What does an open-label design mean? The record lists masking as none. In general, participants and study personnel knowing the assigned dose can influence reporting, care, treatment changes, or outcome assessment. Imaging-based measurement may limit some forms of subjective assessment, but the record does not say whether image assessors were masked, how scans were read, or how disagreements were resolved. Randomization and masking address different sources of bias: randomization concerns assignment, while masking concerns knowledge of assignment after allocation.
How should a binary endpoint be understood? The primary measure counts participants who meet the response threshold of at least 35% spleen-volume reduction at the stated visits. A binary response endpoint places each assessed participant into a response category. In general, this is straightforward to communicate, but it does not show the full distribution of volume changes. Participants just below the threshold and participants with no reduction may be grouped together as nonresponders, while different response magnitudes above the threshold count alike. The registry record does not report participant-level changes or response counts by group.
Why do confidence intervals matter? In general, a confidence interval expresses the uncertainty around an estimated effect under the assumptions of the analysis. A narrow interval indicates more precise estimation than a wide interval; an interval alone does not resolve questions about clinical importance or bias. The registry record does not report a primary-outcome estimate or confidence interval, so precision cannot be assessed for the dose comparison. It also does not report a test statistic or p-value for this endpoint.
What is the role of a significance test? In general, a significance test evaluates how compatible observed data are with a specified null hypothesis, conditional on the test's assumptions. A p-value is not the probability that the null hypothesis is true, nor does a small p-value by itself describe the size or importance of an effect. No primary-endpoint significance test is reported in the registry record. The record also does not report whether any testing was adjusted for multiple endpoints or time points.
What is over-dispersion? General statistical explanation: over-dispersion occurs when outcome variability exceeds what a chosen statistical model assumes. It matters because a model that understates variability can produce overly narrow uncertainty intervals or misleading significance tests. For a binary responder outcome, appropriate modeling depends on the outcome structure, group comparison, and analysis population. The registry record does not identify a primary-endpoint model, so there is no basis to say whether over-dispersion was assessed or relevant to the sponsor's analysis.
What can planning illustrations tell readers? General explanation: sample-size calculations describe how many participants a future study might need under stated assumptions; they are not a measure of the probability that the completed study detected an effect. Any planning illustrations associated with this record are based on a fraction of an observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For non-time-to-event outcomes, such calculations are expressed as participants per arm. They are planning illustrations, not observed power and not a report of the trial's original design rationale. The registry record does not report the trial's own sample-size justification or establish that the illustration assumptions were used when the study was designed.
How should the event counts be read? General explanation: counts depend on the population and observation period in which events are collected. A count alone does not adjust for differences in time exposed to treatment, does not describe recurrent events unless that is explicitly stated, and does not establish causation. The registry provides group counts and at-risk counts for adverse-event summaries, but it does not report exposure-adjusted comparisons or a causal assessment method. These figures therefore support descriptive reading rather than a definitive comparative safety claim.
10. Multiplicity, Missing Data and Analysis Populations
The primary endpoint includes assessments at weeks 12 and 24. Considering more than one assessment time can create a multiplicity issue if each time point is tested separately: in general, repeated testing can increase the chance of at least one false-positive finding unless the analysis plan accounts for it. The registry record does not report whether the time points were tested separately, whether one was designated as more important, or whether any multiplicity adjustment or testing hierarchy was used. No primary-outcome analysis is reported, so the effect of any such approach cannot be evaluated.
The record lists eight outcome measures, including secondary outcomes concerning spleen length, transfusion frequency, performance status, and adverse events. In general, examining several outcomes can also raise multiplicity concerns, particularly if inferential tests are used to support claims. The registry record does not report a statistical analysis plan or describe whether secondary outcomes were treated as descriptive, confirmatory, or exploratory. It does not report adjusted or unadjusted results for these outcomes.
Missing-data handling is also not reported in the registry record. For an imaging endpoint, relevant details could include how missing scans, scans outside the assessment window, or unevaluable scans were classified. The record does not specify whether participants were analyzed according to randomized assignment, treatment received, or another analysis population. It also does not describe how withdrawals, treatment discontinuation, or protocol deviations were handled.
These omissions limit interpretation of any outcome comparisons. The registry record does not report the analysis population, the missing-data method, a multiplicity strategy, or a sponsor statistical analysis for the primary endpoint. Those details should not be inferred from the fact that the study was randomized or that it listed multiple outcomes.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Pacritinib 100 mg QD | 19 | 52 | 36.5% |
| Pacritinib 100 mg BID | 20 | 55 | 36.4% |
| Pacritinib 200 mg BID | 25 | 54 | 46.3% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Pacritinib 100 mg QD | 6 of 52 |
| Pacritinib 100 mg BID | 4 of 55 |
| Pacritinib 200 mg BID | 5 of 54 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Pacritinib 100 mg QD | 24 of 52 |
| Pacritinib 100 mg BID | 34 of 55 |
| Pacritinib 200 mg BID | 36 of 54 |
Most frequent serious adverse event terms
| Event term | Organ system | Pacritinib 100 mg QD | Pacritinib 100 mg BID | Pacritinib 200 mg BID |
|---|---|---|---|---|
| Pneumonia | Infections and infestations | 2 of 52 | 2 of 55 | 5 of 54 |
| Pyrexia | General disorders | 3 of 52 | 2 of 55 | 3 of 54 |
| Dehydration | Metabolism and nutrition disorders | 0 of 52 | 3 of 55 | 2 of 54 |
| Sepsis | Infections and infestations | 1 of 52 | 1 of 55 | 2 of 54 |
| Urinary tract infection | Infections and infestations | 1 of 52 | 2 of 55 | 1 of 54 |
| Clostridium difficile colitis | Infections and infestations | 0 of 52 | 1 of 55 | 2 of 54 |
| Gastroenteritis | Infections and infestations | 0 of 52 | 1 of 55 | 2 of 54 |
| Renal failure acute | Renal and urinary disorders | 1 of 52 | 0 of 55 | 2 of 54 |
| Anaemia | Blood and lymphatic system disorders | 0 of 52 | 1 of 55 | 1 of 54 |
| Cardiac failure | Cardiac disorders | 0 of 52 | 1 of 55 | 1 of 54 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Pacritinib 100 mg QD | Pacritinib 100 mg BID | Pacritinib 200 mg BID |
|---|---|---|---|---|
| Diarrhoea | Gastrointestinal disorders | 6 of 52 | 8 of 55 | 14 of 54 |
| Nausea | Gastrointestinal disorders | 7 of 52 | 7 of 55 | 3 of 54 |
| Thrombocytopenia | Blood and lymphatic system disorders | 3 of 52 | 5 of 55 | 9 of 54 |
| Fatigue | General disorders | 1 of 52 | 7 of 55 | 5 of 54 |
| Anaemia | Blood and lymphatic system disorders | 1 of 52 | 3 of 55 | 6 of 54 |
| Decreased appetite | Metabolism and nutrition disorders | 3 of 52 | 2 of 55 | 3 of 54 |
| Ejection fraction decreased | Investigations | 1 of 52 | 3 of 55 | 2 of 54 |
| Epistaxis | Respiratory, thoracic and mediastinal disorders | 2 of 52 | 1 of 55 | 3 of 54 |
| Bronchitis | Infections and infestations | 3 of 52 | 1 of 55 | 1 of 54 |
| Pyrexia | General disorders | 1 of 52 | 3 of 55 | 1 of 54 |
Serious events with the highest arm-level rate: pneumonia (9.3%), pyrexia (5.8%), dehydration (5.5%), general physical health deterioration (3.8%), epistaxis (3.8%).
The serious adverse-event summary lists the number of participants at risk and the number affected in each dose group. For pacritinib 100 mg once daily, the record lists 52 at risk and 19 affected; for 100 mg twice daily, 55 at risk and 20 affected; for 200 mg twice daily, 54 at risk and 25 affected. These are counts, not adjusted rates. The registry record also lists deaths as 6, 4, and 5, respectively, for the same dose groups. It does not report causes of death or attribute deaths to treatment.
For other adverse events, the record lists the at-risk and affected counts as 52 and 24 for 100 mg once daily, 55 and 34 for 100 mg twice daily, and 54 and 36 for 200 mg twice daily. The listed leading serious-event terms and percentages are pneumonia, 9.3%; pyrexia, 5.8%; dehydration, 5.5%; general physical health deterioration, 3.8%; epistaxis, 3.8%; and gastrointestinal haemorrhage, 3.7%.
In general, adverse-event summaries describe events observed during the study and do not establish that treatment caused them. The registry record does not report exposure-adjusted rates, event severity breakdowns beyond the serious-event designation, or a statistical comparison among groups. The percentages for event terms should not be interpreted as dose-specific comparative risks because the record does not identify their denominators in the registry record for this analysis.
12. What the Result Does, and Does Not, Mean
The record establishes that this was a randomized phase 2 dose-finding study of three pacritinib regimens in people with myelofibrosis previously treated with ruxolitinib. It defines a primary imaging endpoint based on at least 35% spleen-volume reduction at weeks 12 and 24. It also records selected adverse-event counts and other outcomes of interest. These details explain what the study was designed to examine, but design intent is distinct from observed evidence.
The registry record does not report the primary response counts or a comparison across the dose groups. It therefore cannot show the direction or magnitude of a difference, or how precisely such a difference was estimated. The absence of a reported comparison is not evidence that the regimens had the same results; it also is not evidence that one regimen performed better. The appropriate interpretation is that this registry record does not provide the primary-outcome result needed to answer that question.
The safety counts can describe participants recorded as affected, but they do not, on their own, establish that pacritinib caused an event or that one dose is safer than another. Differences in counts cannot be interpreted without the relevant analysis, context about exposure and follow-up, and clarity about how events were collected and attributed. The listed deaths likewise have no reported causes or treatment attribution in this record.
More broadly, a spleen-volume response is one outcome and does not by itself summarize symptoms, function, transfusion needs, or overall health. The registry lists some of these as secondary outcomes, but their results are not reported in the record as summarized. This account consequently supports a bounded conclusion about the trial's design and reported safety summaries, not a clinical recommendation or a judgment that a treatment works or does not work.
13. Why This Trial Matters Statistically
This trial is statistically notable as a randomized dose-finding study rather than a single-dose efficacy comparison. Evaluating three regimens can inform a choice among doses, but sound dose selection depends on interpreting benefit and safety together and on understanding the uncertainty around each estimate. The registry states that dosage selection was the study's purpose, while the primary comparison and formal selection method are not reported in the registry record.
The endpoint also illustrates a common analytical trade-off. A threshold-defined imaging response gives a recognizable responder outcome, but it reduces a range of continuous volume changes to categories. The assessments at weeks 12 and 24 create more than one time-specific view of response. General statistical practice requires clarity about which assessment is primary and how multiple comparisons are handled; these details are not reported in the registry record.
The open-label design is relevant to interpretation even with an imaging-based endpoint. Randomization addresses how treatment groups are formed, whereas masking can limit influences after assignment. The record indicates that masking was none and does not say whether imaging assessment was blinded. This distinction helps readers identify possible sources of bias without assuming that bias necessarily occurred.
Finally, the record demonstrates the difference between registering a study and reporting an analyzable result. It gives a study purpose, population, arms, outcome definition, and selected safety summaries, but no primary-outcome analysis. Without group response counts and estimates of uncertainty, readers cannot evaluate the dose-response pattern or the precision of a comparison. The statistical importance of the trial's question is clear; the posted registry record leaves the central efficacy comparison unanswered.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
Several trial-specific limitations of interpretation arise from what the registry record reports and omits. The primary endpoint is assessed at weeks 12 and 24, but response results at either time are not reported. No group-level effect estimate, uncertainty interval, or hypothesis test is available in the registry record. The record therefore does not support a quantitative comparison of the three doses on the stated primary outcome.
The study was open-label, and the record does not say whether imaging assessors were blinded. It also does not describe scan review procedures, confirmation of responses, or handling of unevaluable imaging. These details matter when a threshold-based endpoint depends on measurement at follow-up visits.
The registry does not report the analysis population, missing-data rules, treatment discontinuation handling, or protocol-deviation approach. It does not describe the statistical analysis plan, multiplicity control across assessment times or outcomes, or the trial's own sample-size justification. These gaps prevent assessment of whether the planned and reported analyses align or how missing observations could affect interpretation.
The safety summaries are descriptive. Exposure-adjusted comparisons, event attribution methods, and causes of death are not reported in the registry record. The listed serious-event percentages lack a stated denominator in the registry record for this analysis, so they should not be treated as dose-specific comparative rates.
Finally, the registry lists selected secondary outcomes but does not report their findings in the record. Details such as participant characteristics, follow-up beyond the stated primary assessment period, dose modifications, and concomitant treatment are also not reported in the registry record. These limits do not establish that the study itself lacked such information; they limit what can be concluded from this registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Phase 2 Study: An Open-Label, Randomized, Phase 2 Dose-Finding Study of Pacritinib in Patients With Primary Myelofibrosis, Post-Polycythemia Vera Myelofibrosis, or Post- Essential Thrombocythemia Myelofibrosis Previously Treated With Ruxolitinib — NCT04884191.
- Registry record last updated 2022-06-01; status last verified 2022-05.
- Results first posted 2022-06-01.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT04884191 is a completed, randomized, open-label, parallel-group phase 2 dose-finding study sponsored by CTI BioPharma. It enrolled 165 people with primary or secondary myelofibrosis previously treated with ruxolitinib and evaluated pacritinib 100 mg once daily, 100 mg twice daily, and 200 mg twice daily. The recorded start date is 2017-07-31, and the primary completion date is 2019-09-04.
The primary endpoint was the count of participants with at least 35% spleen-volume reduction on MRI or CT from baseline to weeks 12 and 24. Secondary outcomes listed include spleen length reduction, transfusion frequency, performance status, and adverse events. Selected safety counts and serious-event terms are reported, but primary response counts and a dose-group analysis are not reported in the registry record. The registry therefore describes the trial question and design without supplying the primary result needed to compare the regimens.