What is the mechanism of action for crizotinib?
Mechanism of action Crizotinib is an inhibitor of receptor tyrosine kinases including ALK, Hepatocyte Growth Factor Receptor (HGFR, c-Met), and Recepteur d’Origine Nantais (RON). Translocations can affect the ALK gene resulting in the expression of oncogenic fusion proteins.
What percentage of crizotinib resistant cases harbor a ROS1 resistance mutation?
Analogous to findings in ALK-positive NSCLC, point mutations in ROS1 have been identified that drive resistance to crizotinib in patients with ROS1-positive disease; a retrospective study found ROS1 mutations in approximately 50% of crizotinib-resistant tumors.
What is ROS1 mutation?
The ROS1 gene mutation seen in NSCLC is really a fusion between ROS1 and another gene. This fusion produces a defective gene that acts as a chance driver, causing cancer cells to multiply excessively. Mutations like the ROS1 rearrangement are often acquired, which means that they are not inherited or present at birth.
What is ROS1 rearrangement?
ROS1 rearrangement defines a molecular subset of NSCLC with distinct clinical characteristics that are similar to those observed in patients with ALK-rearranged NSCLC. Crizotinib shows in vitro activity and early evidence of clinical activity in ROS1-rearranged NSCLC.
What type of drug is crizotinib?
Crizotinib is in a class of medications called kinase inhibitors. It works by blocking the action of a certain naturally occurring substance that may be needed to help cancer cells multiply.
What does ROS1 negative mean?
The false-negatives mean that patients with ROS1-positive lung cancer are less likely to receive indicated targeted therapy with crizotinib (Xalkori, Pfizer) or other investigational agents. ROS1-positive lung cancers are associated with nonsmokers and make up approximately 1% to 2% of NSCLC cases.
What does ROS1-positive mean?
The ROS1 gene can fuse with many different partners. The most common in lung cancer is the CD74 gene. When ROS1 fuses or joins with another gene and causes lung cancer, a patient is said to be ROS1-positive.
What does the ROS1 gene do?
The protein encoded by this gene is a type I integral membrane protein with tyrosine kinase activity. The protein may function as a growth or differentiation factor receptor.
Is crizotinib a pill?
Crizotinib is a pill, taken by mouth. It can be taken with or without food. Take Crizotinib exactly as prescribed. Swallow Crizotinib capsules whole.