acalabrutinib
Calquence (acalabrutinib) is a selective Bruton tyrosine kinase (BTK) inhibitor from AstraZeneca. By locking BTK, it cuts the survival and multiplication signal that malignant B cells rely on, and is used in chronic lymphocytic leukaemia and mantle cell lymphoma, alone or with antibody-based combinations.
This page is based on the EMA product information for Calquence, cross-checked against MedlinePlus; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
A malignant B cell is like a workshop that only runs when an order slip is stamped. BTK is the stamping clerk. Acalabrutinib handcuffs the clerk, so slips go unstamped and the workshop, the cancer cell, stops production and winds down, while cells that do not depend on that clerk keep working.
In simple terms
Acalabrutinib is a targeted medicine called a BTK inhibitor. In CLL and mantle cell lymphoma, the cancerous B cells keep receiving stay-alive and multiply signals through a protein called Bruton tyrosine kinase. Acalabrutinib binds to that protein and switches it off, so the cancer cells stop dividing and gradually die. Because it targets a pathway B cells use, it spares many other cell types.
In depth
Acalabrutinib is a second-generation covalent BTK inhibitor that forms an irreversible bond with the C481 residue in the BTK active site. Blocking BTK prevents phosphorylation of PLCg2 and halts downstream B-cell receptor signalling, suppressing proliferation and survival of malignant B cells and redistributing CLL cells from protective tissue niche into circulation. Its greater selectivity over related kinases such as EGFR, ITK and TEC reduces off-target toxicity.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How acalabrutinib works
- In CLL and mantle cell lymphoma, the cancerous B cells keep receiving stay-alive and multiply signals through a protein called Bruton tyrosine kinase.
- Acalabrutinib is a second-generation covalent BTK inhibitor that forms an irreversible bond with the C481 residue in the BTK active site.
- Blocking BTK prevents phosphorylation of PLCg2 and halts downstream B-cell receptor signalling, suppressing proliferation and survival of malignant B cells and redistributing CLL cells from protective tissue niche into circulation.
- Its greater selectivity over related kinases such as EGFR, ITK and TEC reduces off-target toxicity.
Target: Bruton tyrosine kinase (BTK)
A signalling kinase that B cells need to survive and multiply; malignant B cells in CLL and MCL become dependent on this pathway, so blocking BTK selectively starves the cancer cells.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in European Union
EMA- As monotherapy or with obinutuzumab, for adults with previously untreated chronic lymphocytic leukaemia (CLL)
- With venetoclax, with or without obinutuzumab, for adults with previously untreated CLL
- As monotherapy, for adults with CLL who have received at least one prior therapy
- With bendamustine and rituximab, for adults with previously untreated mantle cell lymphoma (MCL) who are not eligible for autologous stem cell transplant
- As monotherapy, for adults with relapsed or refractory MCL who have not previously received a BTK inhibitor
Official sources
The statements on this page trace back to these records.
- Calquence (acalabrutinib) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- MedlinePlus: acalabrutinib
MedlinePlus, U.S. National Library of Medicine
- Emc SmPC: Acalabrutinib (UK licensed product)
Medicines and Healthcare products Regulatory Agency (EMC)
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.