secwatch.observer — SEC 8-K summary
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Issuer:     RIGEL PHARMACEUTICALS INC (RIGL)
CIK:        0001034842
Form:       8-K
Filed at:   2025-12-10T23:59:59+00:00
Accession:  0001104659-25-119976
Event type: other_material
Sentiment:  positive
Materiality: 0.65
Item codes: 8.01, 9.01
LLM model:  deepseek-v4-flash:cloud@v2

Rigel reports R289 Phase 1b data: 33% RBC-TI in evaluable lower-risk MDS patients
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- 33 patients enrolled (median age 75, median 3 prior therapies); 61% high transfusion burden at baseline.
- 6/18 evaluable transfusion-dependent patients at doses ≥500 mg QD achieved RBC-TI >8 weeks; median duration 22.9 weeks.
- R289 generally well tolerated; most common Grade 3/4 AEs: anemia (18%), neutropenia and pneumonia (each 15%).
- Dose expansion phase ongoing; RP2D selection expected H2 2026.
- R289 granted FDA Orphan Drug and Fast Track designations for MDS.

Source:
  EDGAR index:    https://www.sec.gov/Archives/edgar/data/1034842/000110465925119976/0001104659-25-119976-index.htm
  Primary doc:    https://www.sec.gov/Archives/edgar/data/1034842/000110465925119976/tm2533140d1_8k.htm
  HTML page:      https://secwatch.observer/filing/0001104659-25-119976

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