What is Entrectinib (Rozlytrek)? How it Works, Side Effects and More
Updated: Feb 2
Entrectinib (brand name Rozlytrek) is an oral targeted therapy medication prescribed to many patients with ROS1+ cancer. It can be a very effective treatment and relatively tolerable, as cancer treatments go. The following describes the history of entrectinib, its designation as a first-line ROS1+ NSCLC, side effects and more.
What is Entrectinib (Rozlytrek)?
According to the Rozlytrek website, Entrectinib “is a prescription medicine used to treat adults with non-small cell lung cancer (NSCLC) that has spread to other parts of the body and is caused by an abnormal ROS1 gene.” It is also used to “treat solid tumors (cancer) that are caused by certain abnormal NTRK genes.
Entrectinib was studied in 92 people with ROS1+ metastatic NSCLC across 3 clinical trials. 74% of people who were treated with Entrectinib saw their tumors shrink. The FDA approved Rozlytrek in 2020 and it is emerging as the preferred first line targeted therapy for ROS1+ NSCLC.
How does it treat ROS1+ NSCLC?
Entrectinib targets abnormal ROS1 proteins, binding to them inside cancer cells. This blocks the ROS1 proteins from sending signals. Blocking these signals helps to slow or stop the cancer from growing.
Entrectinib effectively treats the brain, which is important because nearly half of ROS1+ cancer patients will eventually develop brain metastases. However, it does have neurologic side effects that may require a dose reduction or switch to a different oral targeted therapy for some patients.
Entrectinib cannot kill 100% of the cancer cells. While entrectinib therapy may control and shrink the cancer, it cannot cure cancer.
How to take Entrectinib (Rozlytrek)?
Entrectinib is taken once a day, by mouth. It can be taken with or without food, but it should be taken about the same time every day.
An informal survey of patients currently active in our ROS1der community shows that around 20% are currently taking Entrectinib. Of those patients, around 6% have been on the drug for more than three years.
Among the current patients in our community who stopped taking Entrectinib, around 17% stopped taking it because of progression in the brain; around 40% stopped taking it because of progression in the body. A third of those who stopped taking Entrectinib had to change because of tolerability or side effects.
What are the Side Effects of Entrectinib (Rozlytrek)?
Entrectinib may cause serious side effects, including:
Congestive heart failure (manifested by persistent coughing or wheezing, trouble breathing when lying down, sudden weight gain, increasing shortness of breath, tiredness, weakness, fatigue, or swelling in ankles, feet, or legs)
Central nervous system (CNS) effects (e.g., dizziness, changes in your mood, or may affect how you think and cause confusion, hallucinations, and problems with concentration, attention, memory, and sleep).
Bone fractures (increased risk for bone fractures which may happen with or without a fall or other injury).
Liver problems (hepatotoxicity). Blood tests to check your liver function during treatment will be conducted.
Increased uric acid level in your blood (hyperuricemia). Tests may be done before and during your treatment to check the uric acid level in your blood. You may be prescribed medications if you have high blood uric acid levels.
Changes in the electrical activity of your heart called QT prolongation, which is manifested by feeling faint, lightheaded, dizzy, or the heart beating irregularly or fast.
Vision problems. This is manifested by any loss of vision or any change in vision including: double vision, blurry vision, new or increased floaters, seeing flashes of light, or light hurting your eyes.
Additionally, the Rozlytrek website lists the most common side effects:
change in taste
abnormal touch sensation
shortness of breath
confusion, mental status changes, memory problems, and hallucinations
Patients in the “ROS1 Positive (ROS1+) Cancer” group on Facebook have reported other side effects, including: low heart rate, skin rash, and elevated creatinine levels.