Jacobio doses first patient in Phase IIa China trial of JAB-8263 for rheumatoid arthritis

• Jacobio completed first patient dosing in a Phase IIa China trial of oral BET inhibitor JAB-8263 for rheumatoid arthritis.
• The study will assess safety, tolerability, pharmacokinetics, and early signs of benefit, marking an expansion beyond oncology.
• Preliminary oncology results were already presented in 2024 at the American Society of Hematology meeting in myelofibrosis.
• Management described the program as well tolerated to date, with early efficacy signals in oncology that supported the move into autoimmune disease.

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