ROS1 (c-ROS receptor tyrosine kinase proto-oncogene 1) is a gene found in cells that is important for cell growth and survival.

In some people, the ROS1 gene begins to mutate or change and may fuse or join with another gene. This is called a ROS1 fusion or ROS1 rearrangement and can be a driving cause of cancer. When changes in the ROS1 gene cause lung cancer, it’s called ROS1-positive or ROS1+ lung cancer.

ROS1-positive lung cancer can be found through biomarker testing. Biomarker testing tells your healthcare team what mutations or changes cancer cells have, and your results can help guide your healthcare team to the best treatment for you. People with stages 1B through 4B (IB through IVB) non-small cell lung cancer (NSCLC) should ask for comprehensive biomarker testing because it looks for all known biomarkers instead of just a few.

Scientists have found many different types of changes in ROS1 in lung cancer. The most common change in ROS1 found in people with lung cancer is when ROS1 fuses with another gene called CD74. Currently, all ROS-1 positive lung cancers are treated with the same targeted therapy drug options, regardless of the specific type of change in ROS1.

• It occurs in about 2 out of every 100 cases (2%) of lung cancer.
• It most often occurs in a type of NSCLC called adenocarcinoma.
• It's most commonly found in people who are under 60 years old, women, and people who don't have a smoking history.

In some people, the ROS1 gene joins or fuses with a different gene, causing the cells to begin growing out of control. ROS1 fusions can occur in the tissues of many organs, but its most commonly found in the lung. When this happens, it’s called ROS1-positive or ROS1+ lung cancer.

Most targeted therapy treatments come in the form of a pill, but a few are given through an IV or a port (a small tube inserted in a vein). The drug names that end in -ib are pills and can be taken at home. The drug names that end in -mab are given through an IV at a cancer center.

Below is a list of targeted therapy drugs that are approved by the Food and Drug Administration (FDA) for use with ROS1-positive NSCLC. The FDA approves each drug for use in NSCLC at specific stages of the disease.

Everyone is different, and the side effects you may have while receiving treatment can vary. Some people experience side effects, while others don’t. Ask a member of your healthcare team about the possible side effects of your treatment and when to seek medical attention.