A Study to Assess the Effectiveness and Safety of Pacritinib in Patients With VEXAS Syndrome (PAXIS)

Exclusion Criteria25

• Prior allogenic hematopoietic stem cell transplant (allo-HSCT) or solid organ transplant (other than corneal).
• Current use of systemic GCs for conditions other than VEXAS syndrome, which, in the opinion of the Investigator, would interfere with adherence to a GC taper regimen and/or assessment of efficacy.
• More than one prior admission to an intensive care unit due to a VEXAS Syndrome flare within the prior 6 months.
• Received ≥9 units of intensive red blood cell (RBC) transfusions in the 90 days prior to enrollment.
• Known concurrent myelodysplastic syndrome (MDS) requiring antineoplastic treatment, or allo-HSCT, or known high-risk or very high-risk MDS based on the Revised International Prognostic Scoring System (IPSS-R). Participants with MDS who do not meet these criteria may enroll.
• Malignancy within 1 year prior to enrollment with the exception of MDS (per exclusion criterion), curatively treated non-melanoma skin cancer, or curatively treated carcinoma in situ. Participants with pre-malignant hematologic conditions (e.g., monoclonal gammopathy of unknown significance \[MGUS\], clonal cytopenia of unknown significance) may enroll.
• Exposure to hypomethylating agents (HMA) within 6 months prior to enrollment, or exposure to more than 6 cycles of HMAs at any time.
• Exposure to non-GC anti-inflammatory therapy or hematologic support therapy within protocol defined timeframes prior to enrollment
• Exposure to anti-platelet therapy with the exception of low-dose aspirin (≤100 mg daily) within 28 days prior to enrollment.
• Known concomitant multiple myeloma, or serum M-protein ≥3 g/dL, involved-to uninvolved free light chain (FLC) ratio ≥100, or involved FLC level ≥100 mg/dL. Participants with MGUS may enroll.
• Systemic treatment with a strong cytochrome P450 3A4 (CYP3A4) inhibitor or inducer within 5 half-lives prior to enrollment.
• Significant recent bleeding history defined as National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) grade ≥2 within 3 months prior to enrollment, unless precipitated by an inciting event.
• History of clinically significant cardiovascular disease, or clinically significant abnormalities in rhythm or conduction during Screening ECG, including:
• QT corrected by the Fridericia method (QTcF) \> 480 msec within 30 days prior to enrollment; if QTcF is thought to be prolonged due to a modifiable factor (e.g., medication / electrolyte abnormality), QTcF may be re-evaluated
• Severe cardiac event (CTCAE grade ≥3) within 3 months prior to enrollment
• Heart failure resulting in limitations during ordinary activity.
• Arterial or venous thrombotic or embolic events, including deep vein thrombosis, pulmonary embolism, and cerebrovascular accident (including transient ischemic attacks), within 60 days prior to enrollment.
• Moderate or severe hepatic impairment that meets criteria for Child-Pugh Class B or C, or active viral hepatitis.
• Uncontrolled human immunodeficiency virus (HIV) off antiretrovirals, or on antiretrovirals with detectable viral load.
• Positive Quantiferon (or other interferon gamma release assay) during Screening.
• Known history of disseminated mycobacterial infection.
• Concurrent enrollment in another interventional trial, or treatment with an experimental therapy within 28 days or five half-lives prior to enrollment, whichever is longer.
• Pregnant, intending to become pregnant during the trial, or currently breastfeeding/lactating.
• Participants with any acute, active infection requiring systemic antimicrobial treatment at the time of enrollment. Exceptions are made for prophylactic antibiotics or chronic antibiotic therapy for non-acute conditions.
• Known hypersensitivity to pacritinib or any of the following inactive ingredients: microcrystalline cellulose, polyethylene glycol, and magnesium stearate.