Zolbetuximab

Zolbetuximab is a prescription medication indicated in combination with fluoropyrimidine-and platinum-containing chemotherapy for first-line treatment of locally advanced unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma in claudin (CLDN) 18.2-positive tumors.

• Zolbetuximab is available under the following different brand names: Vyloy, zolbetuximab-clzb.

Common side effects of Zolbetuximab include:

• tiredness
• decreased appetite
• diarrhea
• tingling or numbness of the arms or legs
• stomach (abdominal) pain
• constipation
• decreased weight
• fever
• decreased white blood cells, red blood cells and
• platelets
• decreased protein (albumin) in the blood
• changes in kidney function tests
• changes in blood sugar (glucose)
• changes in liver function tests
• changes in body salts (electrolytes) in your blood

Serious side effects of Zolbetuximab include:

• allergic reactions, including anaphylaxis and infusion-related reactions, symptoms include itchy, raised bumps on the skin (hives), breathing problems such as wheezing, coughing that does not go away, throat tightness or change in voice, nausea or vomiting, fever, stomach (abdominal) pain, chest discomfort, increased saliva, chills or shaking back pain 
• severe nausea and vomiting

Rare side effects of Zolbetuximab include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, coordination loss, unsteady, very stiff muscles, high fever, profuse sweating, or tremors.
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult dosage

Lyophilized powder injection

• 100 mg single-dose vial

Gastric or gastroesophageal junction cancer

Adult dosage

• First dose
  • 800 mg/m2 IV
• Subsequent doses
  • 600 mg/m2 IV every 3 weeks, or
  • 400 mg/m2 IV every 2 weeks
  • Continue until disease progression or unacceptable toxicity

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Zolbetuximab has no noted severe interactions with any other drugs
• Zolbetuximab has no noted serious interactions with any other drugs
• Zolbetuximab has no noted moderate interactions with any other drugs
• Zolbetuximab has no noted minor interactions with any other drugs

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, health questions, or concerns.

Contraindications

• None

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Zolbetuximab?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Zolbetuximab?”

Cautions

• Hypersensitivity reactions
  • Can cause hypersensitivity reactions (e.g., anaphylaxis reactions, infusion-related reactions [IRR]); fatal IRRs reported
  • Monitor for signs and symptoms of anaphylaxis (e.g., urticaria, repetitive cough, wheezing, throat tightness/voice changes) during infusion and for at least 2 hours after the infusion is complete
  • Monitor for signs and symptoms of IRRs (e.g., nausea, vomiting, abdominal pain, salivary hypersecretion, pyrexia, chest discomfort, chills, back pain, cough, hypertension)
  • Interrupt infusion and resume at a reduced rate orpermanently discontinue depending on severity
  • Treat severe symptoms according to standard medical practice; monitor until symptoms resolve
  • If moderate hypersensitivity reactions or IRR develop
• Premedicate with antihistamines for subsequent infusions
  • Administer per recommended infusion rates; infusion rate may be gradually increased as tolerated
  • Closely monitor
• Nausea and vomiting
  • Can cause severe nausea and vomiting, especially during the first treatment cycle
  • Pretreat with antiemetics before each infusion
  • Manage patients during and after infusion with antiemetics or fluid replacement per standard guidelines
  • Interrupt infusion or permanently discontinue depending on the severity

Pregnancy and Lactation

• No data available on pregnant patients to inform drug-associated risks
• No embryo-fetal toxicity was observed in animal studies in pregnant mice
• Administer during pregnancy only if the benefit of therapy outweighs the potential risk to the fetus
• Refer to Prescribing Information of fluoropyrimidine- and platinum-containing chemotherapy products for pregnancy testing, contraception, and infertility information
• Lactation
  • No data is available on the presence of zolbetuximab in human milk, its effects on breastfed children, or milk production
  • Advise lactating patients to avoid breastfeeding during treatment and for 8 months after the last dose due to the risk of antibodies excreted in human milk and the potential for adverse reactions in breastfed children