alectinib
Alectinib (Alecensa) is an oral kinase inhibitor used as adjuvant treatment following tumor resection and for the treatment of adults with ALK-positive metastatic non-small cell lung cancer (NSCLC). It blocks the abnormal ALK protein that drives cancer cell growth in ALK-positive tumors, helping to slow or stop the spread of cancer. It is taken by mouth as monotherapy.
This page is based on the European Medicines Agency assessment report for Alecensa and FDA prescribing information, cross-checked with DailyMed and 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
In some lung cancers, a broken switch called ALK gets stuck in the 'on' position, telling cancer cells to keep growing and dividing. Alectinib is like a key that jams that switch in the 'off' position. With the switch blocked, the cancer cells lose their main growth signal and slow down or stop.
In simple terms
Alectinib is a kinase inhibitor that targets a protein called ALK (anaplastic lymphoma kinase). In some lung cancers, changes in the ALK gene create an abnormal protein that is always switched on, sending constant growth signals to cancer cells. Alectinib blocks this abnormal ALK protein, turning off the growth signal. This helps slow or stop the spread of cancer cells. Alectinib is used in adults with ALK-positive non-small cell lung cancer, both as adjuvant treatment after surgery and for metastatic disease.
In depth
Alectinib is a highly selective inhibitor of the anaplastic lymphoma kinase (ALK) tyrosine kinase, including oncogenic ALK fusion variants. It binds to the kinase domain of ALK and inhibits its autophosphorylation and downstream signaling through pathways including STAT3, PI3K/AKT, and MAPK/ERK. Alectinib also inhibits RET at higher concentrations. It is indicated as adjuvant treatment following tumor resection of ALK-positive NSCLC (tumors ≥ 4 cm or node positive) and for treatment of adult patients with ALK-positive metastatic NSCLC, as detected by an FDA-approved test. Alectinib is a substrate of P-glycoprotein and achieves clinically meaningful central nervous system penetration, making it active against CNS metastases common in ALK-positive NSCLC.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How ALK inhibitors switch off a stuck growth signal
- Alectinib is a kinase inhibitor that targets a protein called ALK (anaplastic lymphoma kinase).
- In some lung cancers, a broken switch called ALK gets stuck in the 'on' position, telling cancer cells to keep growing and dividing.
- Alectinib is like a key that jams that switch in the 'off' position.
- With the switch blocked, the cancer cells lose their main growth signal and slow down or stop.
Target: Anaplastic lymphoma kinase (ALK)
Alectinib inhibits the tyrosine kinase activity of ALK and its oncogenic variants (including ALK fusion proteins), blocking downstream signaling pathways that drive proliferation and survival of ALK-positive tumor cells.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in European Union
EMA- Adjuvant treatment following complete tumour resection for adult patients with ALK-positive NSCLC at high risk of recurrence
- First-line treatment of adult patients with ALK-positive advanced NSCLC
- Treatment of adult patients with ALK-positive advanced NSCLC previously treated with crizotinib
Approved uses in United States
FDA- Adjuvant treatment in adult patients following tumor resection of ALK-positive NSCLC (tumors ≥ 4 cm or node positive) as detected by an FDA-approved test
- Treatment of adult patients with ALK-positive metastatic NSCLC as detected by an FDA-approved test
Approved uses in United States
DailyMed- Adjuvant treatment in adult patients following tumor resection of ALK-positive NSCLC (tumors ≥ 4 cm or node positive)
- Treatment of adult patients with ALK-positive metastatic NSCLC
Approved uses in United States
MedlinePlus- Treatment of non-small-cell lung cancer (NSCLC) that has spread to other parts of the body
Official sources
The statements on this page trace back to these records.
- Alecensa (alectinib) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- U.S. Food and Drug Administration: Alecensa prescribing information
U.S. Food and Drug Administration
- DailyMed: ALECENSA capsules label
DailyMed, U.S. National Library of Medicine
- MedlinePlus: alectinib
MedlinePlus, U.S. National Library of Medicine
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.