Indication: Selpercatinib is approved for treating advanced or metastatic rearranged during transfection (RET)-mutant medullary thyroid cancer (MTC) in adults and pediatric patients aged 12 and older requiring systemic therapy. It is also indicated for advanced or metastatic RET fusion-positive thyroid cancer, especially in cases refractory to radioactive iodine when appropriate, and advanced or metastatic RET fusion-positive non-small cell lung cancer (NSCLC) necessitating systemic therapy.

Pharmacology: Functioning as a kinase inhibitor, selpercatinib selectively targets RET kinase and other receptor tyrosine kinases, thereby disrupting cellular signaling pathways crucial for cancer cell proliferation and halting tumor growth.

Dosage and Administration: The recommended dose of selpercatinib is 120 mg taken orally twice daily, with or without food. It comes in capsule form for oral use, and dosage adjustments may be warranted based on individual patient factors and tolerance levels.

Interactions: Selpercatinib’s metabolism primarily involves cytochrome P450 (CYP) 3A enzymes, and caution is advised when co-administering with strong CYP3A inhibitors or inducers, as they may respectively increase or decrease selpercatinib concentrations.

Side Effects: Common side effects of selpercatinib encompass hypertension, elevated liver enzymes, fatigue, constipation, musculoskeletal pain, diarrhea, decreased white blood cell count, increased creatinine, among others. Serious adverse reactions may include hepatotoxicity, hypertension, hemorrhagic events, QT interval prolongation, risk of impaired wound healing, and embryo-fetal toxicity.

Precautions and Warnings: Patients undergoing selpercatinib treatment necessitate regular monitoring for hypertension, hepatotoxicity, bleeding events, QT interval prolongation, and other adverse reactions. Pregnancy is contraindicated unless the potential benefits outweigh the risks, and women of reproductive potential should employ effective contraception during treatment and for at least one week post-treatment.

Overdose Effect: In instances of overdose, patients may experience exacerbated adverse reactions such as hypertension and hepatotoxicity. Management typically involves supportive care and symptomatic treatment, with no specific antidote available. Immediate medical attention should be sought if overdose is suspected.

For comprehensive and up-to-date guidance on selpercatinib usage, including dosing, administration, interactions, side effects, precautions, and warnings, consultation with a healthcare professional or reference to the prescribing information is essential, as details may vary or update over time.