Evaluate Ofirnoflast in Adults With Very Low- to Intermediate-risk Myelodysplastic Syndromes Requiring Transfusions

• Ofirnoflast (HT-6184) is a first-in-class, orally administered small-molecule allosteric inhibitor of the NIMA-related protein kinase 7 (NEK7)-NLRP3 inflammasome, developed to address the inflammatory mechanisms implicated in ineffective hematopoiesis in myelodysplastic syndromes (MDS). Chronic activation of the NLRP3 inflammasome in MDS triggers pyroptosis, driving the ineffective hematopoiesis and cytopenias that define the disease. By selectively targeting NEK7, an essential mediator of NLRP3 assembly, ofirnoflast disrupts this inflammatory cascade without broadly suppressing innate immunity, with the goal of restoring hematopoiesis.
• Participants with very low- to intermediate-risk MDS who have failed one or more prior lines of therapy face limited treatment options and often develop chronic, symptomatic cytopenias requiring ongoing red blood cell (RBC) transfusions, which are associated with iron overload, reduced quality of life, and increased healthcare utilization. This study is designed to evaluate ofirnoflast in this defined, multiply-relapsed population and to identify the optimal dose to advance into a Phase 3 study.
• Enrollment will proceed in two sequential phases. Phase A (Safety Lead-in) will open with five participants administered ofirnoflast, observed for a minimum of 4 weeks. Following this observation period, the Safety Review Committee (SRC) will conduct a formal safety review; if no more than 1 of the 5 participants experiences a dose-limiting toxicity (DLT), enrollment will proceed to Phase B. Phase B (Randomized Enrollment) will dose arms concurrently with an additional formal safety review conducted by the SRC after the first 10 participants randomized.
• For all participants, the study consists of four periods. A Screening Period of up to 28 days prior to first dose will be used to confirm eligibility. A 24-Week Initial Treatment Period begins on Day 1 with administration of the first dose and continues for 24 weeks; all participants receive study intervention for a minimum of 24 weeks to allow complete assessment of hematologic response, with the primary endpoint evaluated during Weeks 1-24 using a landmark assessment at Week 24 to ensure comparability across the population. An Extension Period begins after Week 24 for participants who demonstrate clinical benefit as determined by the investigator; these participants may continue ofirnoflast at their established dose until disease progression.
• The SRC will conduct a dose-selection analysis after enrollment is complete and the last enrolled participant has completed 8 weeks of dosing, with final analysis following completion of the 24-week Initial Treatment Period. Dose selection will be based on a pre-specified composite assessment incorporating RBC transfusion-independence and hematologic improvement response rates by arm, incidence and severity of treatment-emergent adverse events, dose modifications and discontinuations due to toxicity, and pharmacokinetic exposure parameters.
• The SRC will monitor participant safety, including safety signal detection, throughout the study, with the frequency of routine safety reviews subject to adjustment based on observed enrollment rate. All participants will receive best supportive care throughout the study.

Inclusion criteria

• At least 18 years of age at the time of signing informed consent.
• Capable of giving signed informed consent
• Documented diagnosis of very low-, low-, or intermediate-risk MDS
• Documented diagnosis of anemia
• Relapsed or refractory disease after 1 to 3 prior lines of therapy for lower-risk MDS
• Willing to provide a bone marrow aspirate at Screening.
• Life expectancy of more than 6 months at screening.
• Participants of childbearing potential must have a negative pregnancy test at screening (serum) and Day 1 (urine).
• Participants and partners must use contraception consistent with local regulations and protocol-defined criteria during the intervention period and for at least 30 days after the last dose; periodic abstinence and withdrawal are not acceptable methods.

Exclusion criteria

• Anemia due to other causes (e.g., iron deficiency).
• Known clinically significant anemia due to iron, vitamin B12, or folate deficiency; autoimmune or hereditary hemolytic anemia; or gastrointestinal bleeding.
• History of hemoglobinopathies, intrinsic RBC membrane/enzyme defects, or hemolytic anemia.
• Prior history of AML, secondary MDS, or other malignancy (except non-melanoma skin cancer or in situ cervical/breast carcinoma) unless disease-free for >1 year.
• Diagnosis of MPN, CMML, or overlap MDS/MPN per WHO classification.
• Any condition or concomitant treatment that may impair absorption of orally administered study intervention.
• Uncontrolled infection or severe organ dysfunction.
• Concomitant intercurrent illness or condition that, per investigator judgment, would compromise safe participation (e.g., uncontrolled hypertension, uncontrolled seizure, unstable angina, new-onset/exacerbated cardiac arrhythmia).
• Prior treatment with disease-modifying agents (e.g., hypomethylating agents) or immunosuppressive therapy, except prior lenalidomide (permitted).
• Treatment with cytotoxic chemotherapy or experimental agents within 4 weeks prior to first dose.
• History of stem cell, bone marrow, or solid organ transplant.
• Known hypersensitivity to ofirnoflast or its excipients.
• Severe renal or hepatic impairment
• Inability to swallow tablets.
• Participation in another interventional clinical study within 90 days prior to first dose.
• QTcF >480 ms.
• Prior treatment with ofirnoflast.