Last reviewed 2026-04-23 · How we verify

LOXO-305

Selective Bruton's tyrosine kinase (BTK) inhibitor

Selective Bruton's tyrosine kinase (BTK) inhibitor Used for Relapsed or refractory mantle cell lymphoma, Relapsed or refractory marginal zone lymphoma.

At a glance

Mechanism of action

LOXO-305 is a selective inhibitor of Bruton's tyrosine kinase (BTK), a key component of the B-cell receptor signaling complex. Inhibition of BTK has been shown to be effective in treating certain types of non-Hodgkin lymphoma.

Approved indications

• Relapsed or refractory mantle cell lymphoma
• Relapsed or refractory marginal zone lymphoma

Common side effects

• Neutropenia
• Thrombocytopenia
• Anemia
• Fatigue
• Diarrhea

Key clinical trials

• Phase II Study of Pirtobrutinib With Venetoclax In Relapsed-Refractory MCL (Mantle Cell Lymphoma) Patients (PHASE2)
• A Study of Pirtobrutinib (LOXO-305) Versus Ibrutinib in Participants With Chronic Lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL) (PHASE3)
• Study of Oral LOXO-338 in Patients With Advanced Blood Cancers (PHASE1)
• A Study of (LY3527727) Pirtobrutinib in Participants With Previously Treated Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma or Non-Hodgkin Lymphoma (PHASE4)
• A Master Protocol to Evaluate the Long-Term Safety of (LY3527727) Pirtobrutinib (PHASE4)
• LV20.19 CAR T-Cells in Combination With Pirtobrutinib for Relapsed, Refractory B-cell Malignancies (PHASE1)
• Pirtobrutinib (LOXO-305) and Venetoclax for the Treatment of Patients With CLL or SLL Resistant to Covalent BTKi (PHASE2)
• Pirtobrutinib and Venetoclax With MRD Detection for Previously Untreated Chronic Lymphocytic Leukemia (PHASE2)

Primary sources

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