The primary AEs highlighted in the tucatinib prescribing information all appeared as significant PT signals, including: diarrhea, nausea, vomiting, stomatitis, decreased appetite, rash, palmar-plantar erythrodysaesthesia syndrome, hepatotoxicity (markedly elevated alanine aminotransferase [ALT] or AST, jaundice), anemia, and peripheral neuropathy. This evidence concerns the gene GPT and peripheral neuropathy.