Rigel Announces Oral Presentation of Phase 1b Data for R289 in Patients with Lower-Risk MDS at the 68th American Society of Hematology Annual Meeting and Exposition
Key Highlights
- ➤64 patients enrolled in ongoing Phase 1b R289 study as of July 16, 2026
- ➤R289 updated efficacy and safety data scheduled for ASH oral presentation
- ➤81.6% of measured ITP patients reached platelet counts ≥50 × 10³/µL during months 7-12
- ➤799-patient Japan surveillance found no new fostamatinib safety signals
- ➤Fostamatinib produced durable hemoglobin responses in >50% of 71 wAIHA patients through Week 104
Expert Statements
Alison L. Hannah, Chief medical officer of Rigel Pharmaceuticals
“Data from the dose escalation phase of the ongoing Phase 1b study of R289 in patients with relapsed or refractory lower-risk MDS was presented at an oral session at last year's ASH,”
Alison L. Hannah, Chief medical officer of Rigel Pharmaceuticals
“This year the data from our randomized dose expansion phase will also be presented at an oral session, providing an update on both efficacy, including the reduction of transfusion dependence, and safety.”
Alison L. Hannah, Chief medical officer of Rigel Pharmaceuticals
“We continue to be encouraged by our evolving data in this heavily pretreated patient population.”
Rigel Announces Oral Presentation of Phase 1b Data for R289 in Patients with Lower-Risk MDS at the 68th American Society of Hematology Annual Meeting and Exposition PR Newswire
* Oral presentation to feature updated data from the dose escalation and dose expansion phases of the ongoing Phase 1b study evaluating R289, Rigel's dual IRAK1/4 inhibitor, in patients with relapsed or refractory lower-risk MDS * Three poster presentations will highlight data for TAVALISSE(®) (fostamatinib disodium hexahydrate) in patients with chronic ITP and wAIHA SOUTH SAN FRANCISCO, Calif., Nov. 4, 2026 /PRNewswire/ -- Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL), a commercial stage biotechnology company focused on hematologic disorders and cancer, today announced that data from the ongoing Phase 1b clinical study of R289(1), a potent and selective inhibitor of interleukin receptor-associated kinases 1 and 4 (IRAK1/4), in patients with lower-risk myelodysplastic syndrome (MDS) who are relapsed or refractory (R/R) to prior therapies will be presented in an oral session at the 68(th) American Society of Hematology (ASH) Annual Meeting and Exposition on Saturday, December 12, 2026. In addition, the ASH Annual Meeting will feature three poster presentations for TAVALISSE(®) (fostamatinib disodium hexahydrate) in patients with immune thrombocytopenia (ITP) and warm autoimmune hemolytic anemia (wAIHA). The ASH Annual Meeting is taking place from December 12-15, 2026, in New Orleans, Louisiana and virtually.
Get started
Create a free account to read the full story.