Larotrectinib Overview and Detailed Medication Guide

Larotrectinib (Larotrectinib), also known as Vitrakvi or Vitrakvi, is an advanced oral small molecule drug jointly developed by Loxo Oncology and Bayer Pharmaceuticals. The drug was approved by the FDA on November 26, 2018, and will successfully enter the Chinese market in 2022. Larotrectinib is known for its highly selective inhibitory effect on tropomyosin receptor kinase (TRK). It is mainly used to treat patients with advanced or metastatic solid tumors with neurotrophic tyrosine receptor kinase (NTRK) gene fusion. It is suitable for adults and children.

1. Drug action mechanism

Larotrectinib's mechanism of action targetsNTRK gene fusion, which is a carcinogen for a variety of adult and childhood cancers. When chromosomal variation leads to NTRK gene fusion, signaling downstream of TRK kinase is activated, leading to disordered cell proliferation and tumor growth. As a TRK inhibitor, larotinib can precisely block the function of NTRK fusion genes, thereby effectively inhibiting the development of tumors.

2. Scope of indications

Larotrectinib is widely applicable to a variety of tumor types carryingNTRK gene fusions, including at least 17 types of tumors including breast cancer, colorectal cancer, lung cancer, thyroid cancer, melanoma, gastrointestinal cancer, soft tissue sarcoma, salivary gland tumors and infantile fibrosarcoma. This drug does not target a specific cancer type, but targets NTRK gene fusion for targeted treatment, providing a new treatment option for many patients who have failed traditional treatments.

3. Medication Guidelines

1. Medication dosage and method

1) Adult patients: If the body surface area≥1 square meter, it is recommended to take 100 mg orally twice a day, on an empty stomach or with food.

2) Pediatric patients: If the body surface area is <1 square meter, it is recommended to take it orally twice a day, and the dose is calculated as 100 mg/square meter each time; if the body surface area is ≥ 1 square meter, the dose is the same as for adults.

2. Medication precautions

1) Taking the capsule: Swallow the capsule whole and drink it with water to avoid chewing or damaging the capsule.

2) Storage of oral liquid: Oral liquid needs to be stored in the refrigerator (2°C to 8°C). It should be used within 90 days after opening for the first time. It must be discarded after expiration.

3)Treatment of adverse reactions: Common adverse reactions include fatigue, nausea, dizziness, vomiting, etc. If you encounter serious adverse reactions (such as grade 3 or 4), you should seek medical treatment immediately and consider suspending the medication or adjusting the dose.

4) Liver function and neurological monitoring: Liver function and nervous system status need to be monitored regularly during treatment. If there are any abnormalities, the treatment plan should be adjusted under the guidance of a doctor.

5) Contraceptive advice: Animal experiments show that larotrectinib is harmful to the fetus, so patients and partners should take effective contraceptive measures while taking the drug and within one week after stopping the drug.

In short, larotrectinib, as an innovative anti-cancer drug, provides a new treatment approach for tumor patients carryingNTRK gene fusions. When using larotrectinib, patients should strictly follow medical instructions, pay attention to the management of adverse reactions and regular monitoring to ensure the safety and effectiveness of treatment.