TyrosinkinaseHemmer

Tyrosinkinasehemmer (TKIs) are a class of drugs that inhibit the activity of tyrosine kinases, enzymes that transfer a phosphate group to tyrosine residues on proteins. By blocking the phosphorylation of key signaling proteins, TKIs interfere with cell proliferation, survival, angiogenesis and inflammation pathways. The drugs are often used in oncology as they target kinases that are abnormally active in cancer cells, but they are also applied in treating chronic inflammatory diseases and certain rare conditions.

The first generation of TKIs was developed against the epidermal growth factor receptor (EGFR), but the field has expanded rapidly. Examples include imatinib (BCR‑ABL inhibitor), gefitinib and erlotinib (EGFR inhibitors), sorafenib (multikinase inhibitor), vemurafenib and dabrafenib (BRAF inhibitors), and sunitinib (VEGFR/PDGFR inhibitor). Each agent is usually chosen according to the specific genetic mutation or pathway involved in a patient’s disease.

Clinical benefits of TKIs depend on the presence of targetable mutations; however, resistance can develop through secondary mutations, activation of alternative pathways or pharmacokinetic changes. Side effects vary but commonly include skin rash, diarrhoea, fatigue, hypertension, and cardiac or liver toxicity. Management typically involves dose adjustment or supportive care.

Ongoing research focuses on improving selectivity, reducing off‑target effects, and combining TKIs with immunotherapies or other targeted agents to overcome resistance and broaden therapeutic efficacy.