Understanding these potential adverse reactions of Vepdegestrant and their management strategies is key to ensuring safe and smooth treatment.

I. Cardiac‑Related Risks: Focused Monitoring and Active Surveillance

1. QTc Interval Prolongation:

(1) This is a cardiac adverse reaction that requires special attention with Vepdegestrant.

(2) It may affect cardiac electrical activity and increase the risk of serious arrhythmias (e.g., torsades de pointes).

(3) Before and during treatment, physicians will closely monitor this parameter via electrocardiogram (ECG).

2. Association with Electrolyte Disturbances:

(1) Hypokalemia or hypomagnesemia further increase the risk of QTc interval prolongation.

(2) Therefore, it is essential to ensure that serum potassium and magnesium levels remain within the normal range before and during treatment, with regular testing and timely supplementation as directed by the physician.

3. Proactive Recognition of Warning Signs:

(1) Patients at home should seek immediate medical attention if they experience dizziness, palpitations, a sensation of rapid or irregular heartbeat, unexplained syncope, or chest tightness and shortness of breath.

(2) These symptoms may indicate arrhythmias and require urgent medical intervention.

4. Avoiding Additive Risks:

(1) During treatment, avoid using other medications that may prolong the QTc interval.

(2) If such medications are necessary, be sure to inform your physician and increase the frequency of ECG monitoring under medical guidance.

II. Common Systemic Reactions: Active Management to Improve Experience

1. Gastrointestinal Reactions:

(1) Nausea and constipation are relatively common issues during treatment.

(2) To alleviate nausea, try eating smaller, more frequent meals and choose light, easily digestible foods.

(3) For constipation, increasing fluid intake and dietary fiber (e.g., fruits, vegetables, whole grains) may help; if needed, consult your physician about using mild laxatives.

2. General Fatigue and Pain:

(1) Fatigue and musculoskeletal pain are relatively common and may affect daily life.

(2) Patients are advised to plan daily activities according to their energy levels, alternating rest with light activities (such as walking) to conserve energy and reduce pain.

(3) Persistent pain should be reported promptly to the physician for effective symptomatic management.

3. Decreased Appetite:

(1) Loss of appetite may lead to inadequate nutritional intake.

(2) It is recommended to prioritize high‑protein and adequate‑calorie foods, schedule main meals during times of the day when appetite is relatively better, and consider smaller, more frequent meals to meet basic nutritional needs.

III. Laboratory Abnormalities: Regular Monitoring and Timely Adjustment

1. Changes in Blood Cell Counts:

(1) Treatment may cause decreases in white blood cells, red blood cells (hemoglobin), and platelet counts.

(2) This increases the risk of infection, anemia, and bleeding.

(3) Therefore, regular complete blood count monitoring is required. If fever, unusual pallor, or unexplained bruising or bleeding occurs, contact the medical team immediately.

2. Elevated Liver Function Tests:

(1) Vepdegestrant may cause elevations in liver enzymes such as AST, ALT, and alkaline phosphatase.

(2) These are usually reversible but require regular blood monitoring.

3. Renal Function and Metabolic Effects:

(1) Some patients may experience elevated serum creatinine or decreased serum potassium.

(2) Regular monitoring of renal function and electrolyte levels is necessary.

(3) In daily diet, consider including potassium‑rich foods (e.g., bananas, potatoes) to prevent hypokalemia, and ensure adequate fluid intake.