FDA Approval: Acalabrutinib (Calquence) for Leukemia

One disease with two names

CLL and SLL are the same illness seen in two places.

Abnormal B cells, a kind of white blood cell, build up and refuse to die off. When they collect mainly in the blood and bone marrow, it is called chronic lymphocytic leukemia. When they collect mainly in lymph nodes, it is called small lymphocytic lymphoma. The cells are the same.

Those cells stay alive because of a signal carried by a protein called Bruton's tyrosine kinase, shortened to BTK. Acalabrutinib latches onto BTK and shuts the signal down. Without it, the cells stop being told to survive and multiply.

That makes it a targeted therapy, aimed at one protein rather than at dividing cells generally.

What the FDA approved

On November 21, 2019, the FDA approved acalabrutinib, sold as Calquence, for adults with CLL or SLL.

The wording is unusually short. It does not require that anything be tried first. So the drug can be used as a first treatment or after other treatments have stopped working.

This was a regular approval, not an accelerated one. The FDA had full trial evidence rather than an early signal. The drug had first reached the market in 2017, under accelerated approval, for a different disease: mantle cell lymphoma.

The two trials

ELEVATE-TN enrolled 535 people who had never been treated. It compared three groups: acalabrutinib with obinutuzumab, acalabrutinib alone, and chlorambucil with obinutuzumab.

After a median follow-up of 28.3 months, median progression-free survival had not been reached in the acalabrutinib-plus-obinutuzumab group. In the chlorambucil-plus-obinutuzumab group it was 22.6 months, with a 95% confidence interval of 20 to 28 months.

ASCEND enrolled 310 people whose CLL had come back or had never responded. They were split evenly between acalabrutinib and the investigator's choice of treatment. Median progression-free survival had not been reached with acalabrutinib. With the comparison treatments it was 16.5 months, with an interval of 14.0 to 17.1 months.

Two phrases worth pausing on

"Not reached" means that when the analysis was done, more than half of that group was still doing well. So no midpoint could be calculated. It reads as encouraging and it is not a final number.

"Progression-free survival" means how long the leukemia stayed under control. It is a real benefit. It is not the same thing as living longer, and these figures do not show that overall survival improved.

Our explainer on clinical trial phases covers why the endpoint a trial picks limits what it can prove.

What taking it involves

The label recommends 100 mg by mouth about every 12 hours. Capsules are swallowed whole with water, with or without food. That is the label figure; your haematologist's prescription is what to go by.

Use the schedule your own team gave you. Other medicines, especially stomach acid drugs, change how acalabrutinib is taken, so the label figure is only a starting point.

There is no set number of cycles. Treatment continues for as long as it works and is tolerated, which makes it an ongoing commitment rather than a course you finish.

Reactions reported in 30% or more of people were anemia, low neutrophils, upper respiratory infection, low platelets, headache, diarrhea, and musculoskeletal pain. Low blood counts and infections dominate that list, which is why blood counts get checked regularly.

The label's serious warnings cover serious and opportunistic infections, bleeding, low blood counts, second cancers including skin cancers, and atrial fibrillation or flutter. That last one is an irregular heart rhythm, and it is something to report rather than wait out.

When to get checked

CLL usually announces itself quietly. NCI notes that in the beginning it causes no signs or symptoms at all and is often found during a routine blood test.

When symptoms do appear, NCI says to check with a doctor about:

• Painless swelling of lymph nodes in the neck, underarm, stomach, or groin.
• Weakness or feeling tired.
• Pain or a feeling of fullness below the ribs.
• Fever and infection.
• Easy bruising or bleeding.
• Petechiae, meaning flat pinpoint dark-red spots under the skin caused by bleeding.
• Weight loss for no known cause.
• Drenching night sweats.

For anyone already taking acalabrutinib, three things need attention the moment they happen. A fever during treatment that lowers blood counts is a medical emergency — call the care team immediately, at any hour, and say you are on cancer treatment. Bleeding that will not stop, and a heart that starts racing or fluttering, are also reasons to be seen straight away rather than to wait for the next appointment.

The wider picture

The American Cancer Society projects 22,760 new chronic lymphocytic leukemia diagnoses and 4,350 deaths in the United States in 2026, and SEER carries that projection on its own page. SEER itself counted an estimated 235,781 people living with the disease in 2023.

Five-year relative survival in CLL is among the higher figures in the registry, at 90.2 percent for people diagnosed from 2016 through 2022, and it reflects a disease that is often slow. Any such figure is still a population average built from thousands of people over several years, and it describes no individual.

Our overview of leukemia covers how the types differ.

What this does not mean

An approval describes a group, not a person. Whether acalabrutinib fits someone depends on their disease features, their other medicines, their heart and bleeding history, and their own priorities. That is a conversation for a hematologist or oncologist.

Approval is also not a promise of benefit. It means the evidence met the FDA's bar for this use.

And the existence of a drug does not settle whether to start one. Many people with early CLL are monitored rather than treated, and that remains a separate decision from what is available.

Sources

• FDA approval package, CALQUENCE supplements s006/s007 (CLL/SLL), November 21, 2019
• FDA prescribing information: CALQUENCE (acalabrutinib) capsules
• NCI drug information: Acalabrutinib
• NCI PDQ: Chronic Lymphocytic Leukemia Treatment (Patient Version)
• NCI SEER Cancer Stat Facts: Chronic Lymphocytic Leukemia

How this article was prepared

An AI-assisted editorial system helped prepare this page. No named medical reviewer has reviewed it unless one is listed.

See an error, old source, or unclear wording? Tell us.