Repotrectinib, a novel kinase inhibitor, offers a new treatment option for certain lung cancer patients. Understanding its indications, contraindications, and use in special populations is crucial for rational clinical drug use.
Repotrectinib Indications
1. ROS1-positive Non-Small Cell Lung Cancer
Repotrectinib is indicated for the treatment of adult patients with locally advanced or metastatic ROS1-positive non-small cell lung cancer (NSCLC).
Repotrectinib Contraindications and Precautions
1. Drug Contraindications
(1) Potent and intermediate-potency CYP3A inhibitors should be discontinued for 3-5 elimination half-lives before starting repotrectinib treatment.
(2) Concomitant use with P-gp inhibitors, potent and intermediate-potency CYP3A inducers, certain CYP3A substrates, and hormonal contraceptives should be avoided.
(3) Grapefruit juice may increase blood drug concentrations and should be avoided.
2. Central Nervous System Reactions
(1) 75% of patients may experience central nervous system adverse reactions such as dizziness, ataxia, and cognitive impairment, with grade 3-4 events accounting for 4%.
(2) 64% of patients experience dizziness (including vertigo), with 2.8% experiencing grade 3 dizziness.
(3) Patients are advised not to drive or operate machinery during the occurrence of central nervous system adverse reactions.
3. Other Important Warnings
(1) The incidence of interstitial lung disease/pneumonia is 2.9%, with 1.1% experiencing grade 3.
(2) New or worsening lung symptoms should be monitored. Suspected cases should be discontinued immediately, and confirmed cases should be permanently discontinued.
Special Population Use of Repotrectinib
1. Pregnant Women
(1) Based on its mechanism of action, repotrectinib may harm the fetus.
(2) In animal studies, administration of repotrectinib to pregnant rats during organogenesis has led to fetal malformations.
(3) Women of childbearing potential are advised to use effective non-hormonal contraception during treatment and for two months after the last dose.
2. Breastfeeding Women:
There is no data on whether ripretinib enters human breast milk. It is recommended to avoid breastfeeding during treatment and for 10 days after the last dose.
3. Patients with Hepatic Impairment:
(1) Mild hepatic impairment (total bilirubin >1-1.5 times the upper limit of normal or AST > the upper limit of normal) requires no dose adjustment.
(2) The recommended dose for patients with moderate to severe hepatic impairment has not been determined.
4. Pediatric Patients:
The safety and efficacy of ripretinib in pediatric patients with ROS1-positive non-small cell lung cancer have not been established.
Repotrectinib Adverse Reaction Management
1. Common Adverse Reactions
(1) The most common (≥20%) adverse reactions include dizziness (64%), taste disturbance (50%), peripheral neuropathy (47%), constipation (37%), dyspnea (30%), ataxia (29%), fatigue (29%), cognitive impairment (23%), and muscle weakness (21%).
(2) Hepatotoxicity manifests as elevated ALT (35%) and elevated AST (40%).
2. Dosage Adjustment Strategies
(1) Depending on the severity of the adverse reaction, measures such as suspending administration, reducing the dose, or permanently discontinuing the drug may be taken.
(2) Recommended dose reduction regimens include reducing from 160 mg twice daily to 120 mg twice daily, or further to 80 mg twice daily.
