Table of Contents
- What is Crizotinib?
- How Crizotinib Works
- Conditions Treated by Crizotinib
- How Crizotinib is Administered
- Efficacy of Crizotinib
- Side Effects and Safety
- Ongoing Research and Combination Therapies
- Important Considerations for Patients
What is Crizotinib?
Crizotinib, also known by its brand name XALKORI, is a targeted cancer therapy drug used primarily in the treatment of certain types of non-small cell lung cancer (NSCLC)[1]. It belongs to a class of medications called kinase inhibitors, which work by blocking specific proteins that contribute to cancer growth[2].
How Crizotinib Works
Crizotinib specifically targets cancers that have a genetic alteration involving the anaplastic lymphoma kinase (ALK) gene. This gene produces a protein that, when altered, can lead to uncontrolled cell growth and cancer. By inhibiting the ALK protein, crizotinib can help slow or stop the growth of cancer cells[3].
In addition to targeting ALK, crizotinib also inhibits other proteins that may be involved in cancer growth, such as the ROS1 and MET proteins. This makes it potentially effective against cancers with different genetic alterations[2].
Conditions Treated by Crizotinib
Crizotinib is primarily used to treat:
- Non-small cell lung cancer (NSCLC): Specifically, NSCLC that is ALK-positive or ROS1-positive[1]
- Anaplastic large cell lymphoma (ALCL): A rare type of blood cancer[2]
- Inflammatory myofibroblastic tumors (IMT): A rare type of soft tissue tumor[2]
Research is ongoing to explore its potential in treating other types of cancers with specific genetic alterations[2].
How Crizotinib is Administered
Crizotinib is typically taken orally in the form of capsules. The standard dose for adults is usually 250 mg twice daily, taken continuously[1]. However, the exact dosage may vary depending on the patient’s condition, response to treatment, and any side effects experienced.
For patients who have difficulty swallowing capsules, such as some pediatric patients, alternative formulations are being developed. These include an oral solution and an encapsulated microsphere (eMS) formulation, which is being studied to improve palatability and ease of administration[4].
Efficacy of Crizotinib
Clinical trials have shown that crizotinib can be highly effective in treating ALK-positive NSCLC. In a study comparing crizotinib to standard chemotherapy in previously untreated East Asian patients with ALK-positive NSCLC, crizotinib demonstrated superior efficacy in several key areas[1]:
- Progression-free survival (PFS): Crizotinib significantly prolonged the time before the cancer progressed compared to chemotherapy.
- Objective response rate (ORR): A higher percentage of patients treated with crizotinib showed a significant reduction in tumor size.
- Quality of life: Patients on crizotinib reported better overall quality of life and improvement in lung cancer symptoms compared to those on chemotherapy.
Side Effects and Safety
Like all medications, crizotinib can cause side effects. Some of the most common side effects reported in clinical trials include[1][5]:
- Visual disturbances: Such as blurred vision or seeing flashes of light
- Gastrointestinal issues: Including nausea, vomiting, diarrhea, and constipation
- Fatigue
- Edema: Swelling, particularly in the legs and feet
- Liver enzyme abnormalities: Which may require regular blood tests to monitor
More serious but less common side effects can include lung inflammation (pneumonitis) and heart rhythm changes. It’s important for patients to report any side effects to their healthcare provider promptly[5].
Ongoing Research and Combination Therapies
Researchers are continually studying crizotinib to understand its full potential and to explore ways to enhance its effectiveness. Some areas of ongoing research include:
- Combination therapies: Studies are investigating the use of crizotinib in combination with other cancer treatments. For example, a study is looking at combining crizotinib with pembrolizumab, an immunotherapy drug, in ALK-positive NSCLC patients[5].
- Expanded use: Researchers are exploring the use of crizotinib in other types of cancers that have ALK, ROS1, or MET alterations[2].
- Improved formulations: Work is being done to develop new formulations of crizotinib that may be easier to take, especially for patients who have difficulty swallowing capsules[4].
Important Considerations for Patients
If you’re considering or currently taking crizotinib, here are some important points to keep in mind:
- Genetic testing: Crizotinib is most effective in cancers with specific genetic alterations. Your doctor will likely recommend genetic testing of your tumor to determine if crizotinib is appropriate for you[1].
- Regular monitoring: While on crizotinib, you’ll need regular check-ups and tests to monitor your response to the treatment and watch for any side effects[5].
- Drug interactions: Crizotinib can interact with other medications. Always inform your healthcare provider about all medications, supplements, and herbal products you’re taking[5].
- Pregnancy and breastfeeding: Crizotinib may harm an unborn baby. If you’re pregnant, planning to become pregnant, or breastfeeding, discuss this with your doctor before starting treatment.
- Clinical trials: If standard treatments aren’t working for you, you might be eligible for a clinical trial studying new ways to use crizotinib or combining it with other treatments[5].
Remember, while this information provides a general overview, your healthcare team is the best source of information about how crizotinib relates to your specific situation. Don’t hesitate to ask questions and discuss any concerns you may have with your doctor.




