Rigel Announces Oral and Poster Presentations at the 2026 ASCO Annual Meeting and EHA2026 Congress
SOUTH SAN FRANCISCO, Calif., May 21, 2026 /PRNewswire/ -- Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL), a commercial stage biotechnology company focused on hematologic disorders and cancer, today announced the final data from the Phase 3 AcceleRET-Lung clinical trial of GAVRETO ® (pralsetinib) as first-line treatment of rearranged during transfection (RET) fusion-positive non-small cell lung cancer (NSCLC) will be presented in an oral session at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting on Friday, May 29, 2026.
In addition, the ASCO Annual Meeting and European Hematology Association (EHA) 2026 Congress will feature poster presentations that include additional data for pralsetinib and data for REZLIDHIA ® (olutasidenib) for the treatment of relapsed or refractory (R/R) isocitrate dehydrogenase-1 (mIDH1)-mutated acute myeloid leukemia (AML). The ASCO Annual Meeting is being held in Chicago, Illinois and virtually from May 29 to June 2, 2026 and the EHA2026 Congress is being held in Stockholm, Sweden and virtually from June 11 to June 14, 2026.
"Having an oral presentation at ASCO as well as multiple additional data presentations at both upcoming medical conferences underscores the continued clinical relevance of our oncology portfolio. We're pleased that data from the AcceleRET-Lung clinical study will be presented for the first time and the real-world outcome data for olutasidenib will be presented for patients with relapsed/refractory mIDH1 AML previously treated with venetoclax, further validating its role as a treatment option for these patients," said Raul Rodriguez, Rigel's president and CEO. "Together, these data reinforce our ability to deliver targeted therapies that significantly improve the lives of patients with difficult-to-treat cancers. We look forward to sharing these data with the medical community."
Key highlights from the presentations at ASCO and EHA include:
ASCO Annual Meeting abstracts may be accessed online via https://www.asco.org/abstracts. EHA2026 Congress abstracts may be accessed online via the EHA Library.
ASCO Presentations
Abstract Title
Lead Author / Presenter
Presentation Type / Abstract #
Session Title
Session Date / Time (CT)
GAVRETO (pralsetinib)
Efficacy and safety of pralsetinib as first-line treatment of RET fusion-positive advanced or metastatic non-small cell lung cancer (NSCLC): The phase 3 AcceleRET-Lung study
Sanjay Popat, MBBS, FRCP, PhD
Oral presentation #8504
Lung Cancer—Non-Small Cell Metastatic
Friday, May 29, 2026 1:00pm – 4:00pm
Efficacy and safety of pralsetinib in advanced or metastatic RET-altered thyroid cancer (TC): Final analysis of the phase 1/2 ARROW study
Vivek Subbiah, MD
Poster presentation #6028
Head and Neck Cancer
Saturday, May 30, 2026
1:30pm – 4:30pm
Efficacy and Safety of Pralsetinib in RET Fusion-Positive Solid Tumors: Data From the TAPISTRY Trial
Chia-Chi Lin, MD, PhD
Poster presentation #3144
Developmental Therapeutics—Molecularly Targeted Agents and Tumor Biology
Saturday, May 30, 2026
1:30pm – 4:30pm
Clinical factors driving use of RET inhibitor pralsetinib and associated real-world outcomes in RET fusion–positive NSCLC: A retrospective chart review
Makenzi Evangelist, MD
Publication #e20731
Lung Cancer—Non-Small Cell Metastatic
REZLIDHIA (olutasidenib)
Acute myeloid leukemia (AML) patient, disease, and molecular characteristics associated with a long-term (LT) response to olutasidenib
Justin M. Watts, MD
Poster presentation #6523
Hematologic Malignancies—Leukemia, Myelodysplastic Syndromes, and Allotransplant
Monday, June 1, 2026
9:00am – 12:00pm
Real-World Treatment Patterns and Outcomes with Olutasidenib After Venetoclax in IDH1-Mutated AML Using EHR Data
Yasmin Abaza, MD
Publication #e18514
Hematologic Malignancies—Leukemia, Myelodysplastic Syndromes, and Allotransplant
Treatment Patterns and Outcomes with Olutasidenib After Venetoclax in IDH1-Mutated AML Using Real-World Data from Chart Review
Pinkal Desai, MD, MPH
Publication #e18527
Hematologic Malignancies—Leukemia, Myelodysplastic Syndromes, and Allotransplant
Evaluating the cost per month of response for olutasidenib (OLU) versus ivosidenib (IVO) for patients with relapsed/refractory (R/R) mutant IDH1 (mIDH1) acute myeloid leukaemia (AML)
Yasmin Abaza, MD
Publication #e18504
Hematologic Malignancies—Leukemia, Myelodysplastic Syndromes, and Allotransplant
EHA Presentations
Abstract Title
Lead Author / Presenter
Presentation Type / Abstract #
Session Date / Time (CEST)
REZLIDHIA (olutasidenib)
Treatment Patterns and Outcomes with Olutasidenib After Venetoclax in IDH1-Mutated AML Using Real-World Data from Chart Review
Pinkal Desai, MD, MPH
Poster presentation #PS1502
Saturday, June 13, 2026 (18:45 - 19:45 CEST)
Acute myeloid leukemia (AML) patient, disease, and molecular characteristics associated with a long-term (LT) response to olutasidenib
Stéphane de Botton, MD, PhD
Poster presentation #PS1625
Saturday, June 13, 2026 (18:45 - 19:45 CEST)
Delphi Consensus on Optimal Treatment Strategies Using IDH1 Inhibitors in Patients with R/R mIDH1 AML
Justin M. Watts, MD
Publication #PB2795
Real-World Treatment Patterns and Outcomes with Olutasidenib After Venetoclax in IDH1-Mutated AML Using EHR Data
Yasmin Abaza, MD
Publication #PB2610
TAVALISSE (fostamatinib disodium hexahydrate)
Health-Related Quality of Life (HRQoL) Among Patients With Immune Thrombocytopenia (ITP) Treated With Fostamatinib in the FORTE Study
Amber Afzal, MD, MSCI
Publication #PB4295
About NSCLC
It is estimated that over 229,000 adults in the U.S. will be diagnosed with lung cancer in 2026. Lung cancer is the leading cause of cancer death in the U.S., with non-small cell lung cancer (NSCLC) being the most common type accounting for 77% of all lung cancer diagnoses. 1 RET fusions are implicated in approximately 1-2% of patients with NSCLC. 2
About AML
Acute myeloid leukemia (AML) is a rapidly progressing cancer of the blood and bone marrow that affects myeloid cells, which normally develop into various types of mature blood cells. AML occurs primarily in adults and accounts for about 1 percent of all adult cancers. The American Cancer Society estimates that there will be about 22,720 new cases in the United States, most in adults, in 2026. 3
Relapsed AML affects about half of all patients who, following treatment and remission, experience a return of leukemia cells in the bone marrow. 4,5 Refractory AML, which affects between 10 and 40 percent of newly diagnosed patients, occurs when a patient fails to achieve remission even after intensive treatment. 6 Quality of life declines for patients with each successive line of treatment for AML, and well-tolerated treatments in relapsed or refractory disease remain an unmet need.
About ITP
In patients with immune thrombocytopenia (ITP), the immune system attacks and destroys the body's own blood platelets, which play an active role in blood clotting and healing. Common symptoms of ITP are excessive bruising and bleeding. Patients suffering with chronic ITP may live with an increased risk of severe bleeding events that can result in serious medical complications or even death. Current therapies for ITP include steroids, blood platelet production boosters (TPO-RAs), and splenectomy. However, not all patients respond to existing therapies. As a result, there remains a significant medical need for additional treatment options for patients with ITP.
About GAVRETO ® (pralsetinib)
INDICATIONS
GAVRETO (pralsetinib) is indicated for the treatment of:
*This indication is approved under accelerated approval based on overall response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trial(s).
IMPORTANT SAFETY INFORMATION
WARNING: SERIOUS INFECTIONS, INCLUDING OPPPORTUNISTIC INFECTIONS
GAVRETO may increase the risk for serious infections, including bacterial, fungal, viral and opportunistic infections, which can lead to hospitalization or death. Withhold, reduce the dose or permanently discontinue GAVRETO based on severity.
WARNINGS AND PRECAUTIONS
ADVERSE REACTIONS
DRUG INTERACTIONS
Lactation: Advise women not to breastfeed during treatment with GAVRETO and for 1 week after the last dose.
Pediatric Use: Monitor open growth plates in adolescent patients. Consider interrupting or discontinuing GAVRETO if abnormalities occur.
Click here for Important Safety Information and Full Prescribing Information, including Boxed WARNING.
About REZLIDHIA ®
INDICATION
REZLIDHIA is indicated for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with a susceptible isocitrate dehydrogenase-1 (IDH1) mutation as detected by an FDA-approved test.
IMPORTANT SAFETY INFORMATION
WARNING: DIFFERENTIATION SYNDROME
Differentiation syndrome, which can be fatal, can occur with REZLIDHIA treatment. Symptoms may include dyspnea, pulmonary infiltrates/pleuropericardial effusion, kidney injury, hypotension, fever, and weight gain. If differentiation syndrome is suspected, withhold REZLIDHIA and initiate treatment with corticosteroids and hemodynamic monitoring until symptom resolution.
WARNINGS AND PRECAUTIONS
Differentiation Syndrome
REZLIDHIA can cause differentiation syndrome. In the clinical trial of REZLIDHIA in patients with relapsed or refractory AML, differentiation syndrome occurred in 16% of patients, with grade 3 or 4 differentiation syndrome occurring in 8% of patients treated, and fatalities in 1% of patients. Differentiation syndrome is associated with rapid proliferation and differentiation of myeloid cells and may be life-threatening or fatal. Symptoms of differentiation syndrome in patients treated with REZLIDHIA included leukocytosis, dyspnea, pulmonary infiltrates/pleuropericardial effusion, kidney injury, fever, edema, pyrexia, and weight gain. Of the 25 patients who experienced differentiation syndrome, 19 (76%) recovered after treatment or after dose interruption of REZLIDHIA. Differentiation syndrome occurred as early as 1 day and up to 18 months after REZLIDHIA initiation and has been observed with or without concomitant leukocytosis.
If differentiation syndrome is suspected, temporarily withhold REZLIDHIA and initiate systemic corticosteroids (e.g., dexamethasone 10 mg IV every 12 hours) for a minimum of 3 days and until resolution of signs and symptoms. If concomitant leukocytosis is observed, initiate treatment with hydroxyurea, as clinically indicated. Taper corticosteroids and hydroxyurea after resolution of symptoms. Differentiation syndrome may recur with premature discontinuation of corticosteroids and/or hydroxyurea treatment. Institute supportive measures and hemodynamic monitoring until improvement; withhold dose of REZLIDHIA and consider dose reduction based on recurrence.
Hepatotoxicity
REZLIDHIA can cause hepatotoxicity, presenting as increased alanine aminotransferase (ALT), increased aspartate aminotransferase (AST), increased blood alkaline phosphatase, and/or elevated bilirubin. Of 153 patients with relapsed or refractory AML who received REZLIDHIA, hepatotoxicity occurred in 23% of patients; 13% experienced grade 3 or 4 hepatotoxicity. One patient treated with REZLIDHIA in combination with azacitidine in the clinical trial, a combination for which REZLIDHIA is not indicated, died from complications of drug-induced liver injury. The median time to onset of hepatotoxicity in patients with relapsed or refractory AML treated with REZLIDHIA was 1.2 months (range: 1 day to 17.5 months) after REZLIDHIA initiation, and the median time to resolution was 12 days (range: 1 day to 17 months). The most common hepatotoxicities were elevations of ALT, AST, blood alkaline phosphatase, and blood bilirubin.
Monitor patients frequently for clinical symptoms of hepatic dysfunction such as fatigue, anorexia, right upper abdominal discomfort, dark urine, or jaundice. Obtain baseline liver function tests prior to initiation of REZLIDHIA, at least once weekly for the first two months, once every other week for the third month, once in the fourth month, and once every other month for the duration of therapy. If hepatic dysfunction occurs, withhold, reduce, or permanently discontinue REZLIDHIA based on recurrence/severity.
ADVERSE REACTIONS
The most common (≥20%) adverse reactions, including laboratory abnormalities, were aspartate aminotransferase increased, alanine aminotransferase increased, potassium decreased, sodium decreased, alkaline phosphatase increased, nausea, creatinine increased, fatigue/malaise, arthralgia, constipation, lymphocytes increased, bilirubin increased, leukocytosis, uric acid increased, dyspnea, pyrexia, rash, lipase increased, mucositis, diarrhea and transaminitis.
DRUG INTERACTIONS
LACTATION
Advise women not to breastfeed during treatment with REZLIDHIA and for 2 weeks after the last dose.
GERIATRIC USE
No overall differences in effectiveness were observed between patients 65 years and older and younger patients. Compared to patients younger than 65 years of age, an increase in incidence of hepatotoxicity and hypertension was observed in patients ≥65 years of age.
HEPATIC IMPAIRMENT
In patients with mild or moderate hepatic impairment, closely monitor for increased probability of differentiation syndrome.
Click here for Important Safety Information and Full Prescribing Information, including Boxed WARNING.
About TAVALISSE ®
Indication
TAVALISSE (fostamatinib disodium hexahydrate) tablets is indicated for the treatment of thrombocytopenia in adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment.
Important Safety Information
Warnings and Precautions
Drug Interactions
Adverse Reactions
Click here for Important Safety Information and Full Prescribing Information.
To report side effects of prescription drugs to the FDA, visit www.fda.gov/medwatch or call 1-800-FDA-1088 (800-332-1088).
GAVRETO, REZLIDHIA and TAVALISSE are registered trademarks of Rigel Pharmaceuticals, Inc.
About Rigel
Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL) is a biotechnology company dedicated to discovering, developing and providing novel therapies that significantly improve the lives of patients with hematologic disorders and cancer. Founded in 1996, Rigel is based in South San Francisco, California. For more information on Rigel, the Company's marketed products and pipeline of potential products, visit www.rigel.com.
Forward Looking Statements
This press release contains forward-looking statements relating to, among other things, the presentation of data at the 2026 ASCO Annual Meeting and EHA2026 Congress, the potential therapeutic benefit and clinical utility of pralsetinib and olutasidenib, including the potential impact of treatment sequencing, and Rigel's expectations regarding the development and commercialization of its products and product candidates. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. Words such as "look forward," "suggest," "may," "potential," "expect," and similar expressions are intended to identify such forward-looking statements. Forward-looking statements are based on Rigel's current expectations and assumptions and are subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. These risks and uncertainties include, without limitation, risks that clinical trial or real-world data may not be predictive of future clinical outcomes or results in broader patient populations; risks that further data, analyses or experience may alter current understanding of the safety, efficacy or therapeutic utility of pralsetinib or olutasidenib; risks associated with the timing, conduct and availability of data analyses and scientific presentations; risks associated with the commercialization and market acceptance of Rigel's products; and other risks described from time to time in Rigel's filings with the Securities and Exchange Commission, including its Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 and subsequent filings. Any forward-looking statement contained in this press release speaks only as of the date on which it was made. Rigel undertakes no obligation to update any forward-looking statements contained herein, except as required by law.
Contact for Investors & Media:
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[email protected]
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646.461.6387
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SOURCE Rigel Pharmaceuticals, Inc.