Erlotinib
Erlotinib, marketed under the brand name Tarceva, is a medication used in the treatment of various types of cancer. It belongs to a class of drugs known as tyrosine kinase inhibitors (TKIs), which work by blocking the action of a protein called epidermal growth factor receptor (EGFR). This inhibition slows down or stops the growth and spread of cancer cells in the body. Erlotinib is commonly prescribed for non-small cell lung cancer (NSCLC) and pancreatic cancer, among other malignancies.
Impact of Gene Variant
Gene variants can significantly impact the effectiveness of erlotinib treatment. One of the most studied genetic alterations associated with response to erlotinib is the presence of mutations in the EGFR gene. Patients with certain EGFR mutations, such as exon 19 deletions or exon 21 L858R substitutions, tend to derive greater benefit from erlotinib therapy compared to those without these mutations. These mutations make the cancer cells more dependent on EGFR signaling for their growth and survival, making them more susceptible to EGFR inhibitors like erlotinib.
Additionally, other genetic factors, such as variations in drug metabolism enzymes or drug transporters, can influence the metabolism and distribution of erlotinib in the body, affecting its efficacy and toxicity profile.