Xalkori (Crizotinib): What It Is and What to Expect

Xalkori is the brand name. Crizotinib is the generic name. It comes as capsules, and as oral pellets for children, and it blocks two faulty proteins, ALK and ROS1. Neither is a normal part of adult lung tissue. They appear when a gene breaks and joins to a neighbour, and the joined gene then drives the cancer.

This matters for who it helps. Without one of those changes, crizotinib has nothing to block. An FDA-approved test on tumor tissue, or sometimes on blood, is what decides. Ask which change was found in your tumor, because the two are not the same and treatment choices differ.

• Non-small cell lung cancer that has spread, in adults, when the tumor is ALK-positive or ROS1-positive.
• Anaplastic large cell lymphoma that is ALK-positive and has come back or not responded, in children from age 1 and in young adults. The label notes that it has not been shown to work in older adults with this lymphoma.
• Inflammatory myofibroblastic tumor that is ALK-positive and cannot be removed by surgery, or has come back, in adults and children from age 1.

For adults the label's usual amount is 250 mg twice a day, though what your own prescription says is what you take — kidney function, liver function and interacting medicines all change it. Children with lymphoma are dosed by body size, calculated by the oncology pharmacy.

That is the label's adult amount. Your own thoracic oncology team decides what you take, and they often reduce it for eye, liver or heart-rhythm side effects.

Vision problems are among the most common effects, and they usually begin within a week of starting. Most people describe flashes, trailing lights, or blurring, often worst when moving between light and dark. Serious loss of sight is rare: a grade 4 visual field defect with vision loss occurred in 0.2% of 1,719 people in lung cancer trials.

Visual symptoms are reviewed at every visit, and children on this drug get full eye examinations on a fixed calendar the team sets — early, then repeating. Report any new visual symptom rather than waiting to see if it settles.

Liver blood tests are checked frequently in the first two months and regularly after that, and blood counts on their own schedule — your team calendars both, and the appointments are how trouble gets caught early. Crizotinib can also slow the heart, so pulse and blood pressure are monitored, and other medicines that slow the heart may need reviewing. It can lengthen the QT interval on an ECG.

Lung inflammation is the rarest of these but the most urgent. New breathlessness, a new cough, or a fever needs assessing quickly, because it can look like a chest infection and be something else.

Swallow whole, twice a day, with or without food. Do not adjust the dose yourself. Many medicines and grapefruit change how much crizotinib reaches your blood, so check before adding anything, including over-the-counter products and herbal remedies.

ALK-positive and ROS1-positive cancers often respond well at first and then start growing again. Several newer drugs aimed at the same targets are now approved. If scans change, that is a conversation about the next option, not the end of the road.

• Call 911 or go to an emergency department if you become suddenly breathless at rest, your chest hurts, or you faint or feel about to faint with a very slow pulse.
• Call your care team the same day if a cough or breathlessness is new or getting worse, especially with a temperature of 100.4°F (38°C) or higher, or if part of your sight disappears.
• Call your care team within a day or two if you start seeing flashes, trailing lights or blurring, or if your skin or eyes look yellow, your urine turns dark, or your stomach aches under the right ribs.

https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2a51b0de-47d6-455e-a94c-d2c737b04ff7

https://www.cancer.gov/about-cancer/treatment/drugs/crizotinib