Sotorasib is an oral targeted cancer therapy drug that received U.S. FDA approval in May 2021 (marketed under the brand name Lumakras). It is indicated for the treatment of adult patients with non-small cell lung cancer (NSCLC) or colorectal cancer (CRC) harboring the KRAS G12C mutation.
FDA-Approved Indications for Sotorasib
1. KRAS G12C-Mutated Locally Advanced or Metastatic Non-Small Cell Lung Cancer (NSCLC)
Indicated for adult patients with locally advanced or metastatic NSCLC harboring the KRAS G12C mutation who have received at least one prior systemic therapy.
2. KRAS G12C-Mutated Metastatic Colorectal Cancer (mCRC)
Used in combination with panitumumab for adult patients who have previously received chemotherapy regimens containing fluoropyrimidine, oxaliplatin, and irinotecan.
Sotorasib should be administered under the guidance of a medical specialist only after the presence of the KRAS G12C mutation has been confirmed through diagnostic testing. Currently, the safety and efficacy of Sotorasib in pediatric populations have not been established.
Mechanism of Action of Sotorasib
Sotorasib functions by specifically targeting the KRAS G12C mutation—a key driver of tumor growth. It irreversibly binds to this mutated protein, locking it in an "off" state; this action blocks the signaling pathways that drive cancer cell proliferation, thereby leading to the arrest of tumor growth and cancer cell death.
Sotorasib is classified as a RAS GTPase inhibitor; it acts exclusively on cells harboring this specific mutation and has no effect on normal cells. In the treatment of colorectal cancer, the combination of Sotorasib with agents that block the EGFR pathway has demonstrated superior efficacy compared to monotherapy.
Side Effects of Sotorasib
1. Common Side Effects in NSCLC Monotherapy
Diarrhea, musculoskeletal pain, nausea, fatigue, cough, and abnormalities in certain blood test parameters. 2. Common Side Effects of Panitumumab Combination Therapy for CRC
Rash, dry skin, diarrhea, mouth sores, fatigue, musculoskeletal pain, and abnormalities in certain blood test results.
3. Serious Side Effects and Warnings:
Liver Injury: Abnormal liver function is common and may be severe; liver function must be monitored prior to starting treatment and throughout the course of therapy. Signs typically include: jaundice (yellowing of the skin or whites of the eyes), dark urine, pale stools, fatigue, nausea/vomiting, bleeding or bruising, loss of appetite, or pain/tenderness in the upper right abdomen.
Lung or Breathing Problems: May cause fatal lung inflammation. Seek immediate medical attention if you experience new or worsening shortness of breath, coughing, or fever. Your doctor may adjust the dosage, temporarily suspend treatment, or permanently discontinue the medication.
Sotorasib Administration Guide
1. Precautions Before Use
Inform your doctor of any history of liver disease, lung disease (other than lung cancer), or plans regarding pregnancy/breastfeeding: During pregnancy, use only if the potential benefit outweighs the potential risk, as the medication may be harmful to the fetus; during breastfeeding, it is not recommended to breastfeed while taking the medication or for at least one week after the final dose.
2. Administration Instructions
Dosage and Timing: Take 960 mg of Sotorasib orally once daily at a fixed time each day. It may be taken with or without food.
Method of Administration: Swallow the tablets whole; do not chew, crush, or split the tablets.
For Patients with Swallowing Difficulties: Disperse the tablets in 120 mL of non-carbonated, room-temperature water. Stir until the tablets break down into small particles (the tablets will not dissolve completely). Drink the mixture immediately or within 2 hours. Rinse the container with another 120 mL of water and drink the rinse. If the mixture is not consumed immediately, stir it again before drinking.
Combination Therapy Regimen: When treating colorectal cancer, take Sotorasib first, followed by the intravenous infusion of Panitumumab. If Sotorasib treatment is temporarily suspended or permanently discontinued, the Panitumumab treatment schedule will be adjusted accordingly.
Missed Doses: If a dose is missed by more than 6 hours, skip the missed dose and take the next scheduled dose at the usual time the following day; do not take a double dose to make up for a missed dose. Drug Interactions: Inform your doctor about all medications you are currently taking, including prescription drugs, over-the-counter medications, herbal remedies, and dietary supplements.
Antacids: If antacids are required, Sotorasib should be taken at least 4 hours before or 10 hours after the administration of the antacid.
Use in Specific Populations
Pregnant Women: Animal studies have shown maternal toxicity but no embryo-fetal lethality; human data are lacking, and the potential benefits must be weighed against the potential risks.
Breastfeeding Women: The drug may be excreted into breast milk; it is recommended to discontinue breastfeeding.
Pediatric Patients: The safety and efficacy of this drug in children have not been established.
Drug Interactions and Storage
Interaction Checker: Use a drug interaction checker tool by entering the medication names to obtain a detailed report.
Storage Conditions: Store at room temperature (20°C–25°C) and keep out of the reach of children.
Drug Ingredients
Active Ingredient: Sotorasib
Excipients: Microcrystalline cellulose, lactose monohydrate, croscarmellose sodium, magnesium stearate.
Coating Materials: Polyvinyl alcohol, titanium dioxide, polyethylene glycol, talc, yellow iron oxide (red iron oxide is included only in the 320 mg tablets).
