Panitumumab
Pronunciation: (pa-ni-TOO-mu-mab).
- Generic name
- panitumumab
- Brand names
- Panimab, Vectibix, Panitumab
- Drug class
- Monoclonal Antibody; Epidermal Growth Factor Receptor (EGFR) Inhibitor; Antineoplastic Agent
Availability and supply rules vary by country
Trade names by country: United States · Canada
Australia: · Full directory
What panitumumab is and how it works
Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.
Mechanism of action: how panitumumab works
Panitumumab is a fully human IgG2 monoclonal antibody that binds specifically to the extracellular domain of the epidermal growth factor receptor (EGFR). By blocking ligand-induced activation of EGFR, panitumumab inhibits downstream signaling pathways involved in cell proliferation, survival, angiogenesis, and metastasis. This leads to inhibition of tumor growth in cancers that are dependent on EGFR signaling, particularly in RAS wild-type colorectal cancer. (1)
What panitumumab is used for
Metastatic colorectal cancer (mCRC) with wild-type RAS
Metastatic colorectal cancer (mCRC) with wild-type RAS (1)
First-line treatment of mCRC in combination with FOLFOX
First-line treatment of mCRC in combination with FOLFOX (1)
Second-line treatment of mCRC in combination with FOLFIRI
Second-line treatment of mCRC in combination with FOLFIRI (1)
Monotherapy for mCRC after failure of fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy
Monotherapy for mCRC after failure of fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy (1)
Before taking panitumumab
Do not take / not appropriate for
- Contraindicated in patients with known hypersensitivity to panitumumab or any excipients. (Contraindication) (1)
- Not recommended in patients with RAS-mutant colorectal cancer, as efficacy is lacking. (Contraindication) (1)
Tell your clinician about
(1)How to take panitumumab
- General Instructions: Panitumumab is administered by a healthcare professional as an intravenous infusion, usually every 2 weeks. The dose and schedule depend on your body weight and treatment plan.. Adult Dosing: Recommended dose is 6 mg/kg given as an intravenous infusion over 60 minutes every 2 weeks. Dose adjustments may be required based on side effects.. Pediatric Dosing: Safety and efficacy in children have not been established; use in pediatric patients is not routinely recommended.. Administration: Given as an IV infusion in a clinic or hospital setting. Do not self-administer.. When To Stop: Treatment may be stopped if you develop severe or life-threatening side effects, or if your doctor determines the medication is no longer effective.. Storage: Store unopened vials in a refrigerator at 2°C to 8°C (36°F to 46°F). Do not freeze. Protect from light. Prepared solutions should be used promptly or stored as directed by the healthcare provider.
- This page does not provide a dose calculator. Dosing must follow the prescriber, pharmacist, or product label.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1)
Missed dose
If you miss an infusion appointment, contact your healthcare provider as soon as possible to reschedule. Do not attempt to make up a missed dose on your own.
Overdose
In case of suspected overdose, seek immediate medical attention. Overdose may increase the risk of severe side effects such as skin toxicity, electrolyte disturbances, and infusion reactions. Supportive care and monitoring are recommended. (1)
Side effects
Side effects and their urgency vary; report severe, persistent, or concerning symptoms to a healthcare professional.
Acneiform rash
Incidence: Reported in the clinician-authored database; frequency not established
Diarrhea
Incidence: Reported in the clinician-authored database; frequency not established
Hypomagnesemia
Incidence: Reported in the clinician-authored database; frequency not established
Fatigue
Incidence: Reported in the clinician-authored database; frequency not established
Nausea
Incidence: Reported in the clinician-authored database; frequency not established
Abdominal pain
Incidence: Reported in the clinician-authored database; frequency not established
Pulmonary fibrosis
Incidence: Reported in the clinician-authored database; frequency not established
Infusion-related reactions
Incidence: Reported in the clinician-authored database; frequency not established
Serious warnings
US FDA BOXED WARNING — Dermatologic toxicity — serious
Symptoms: US FDA BOXED WARNING — Dermatologic toxicity: severe dermatologic toxicity occurred in the majority of patients receiving panitumumab, and can be complicated by serious infection, including sepsis, septic death, and abscesses requiring incisions and drainage. Your oncology team will withhold panitumumab for severe or life-threatening dermatologic toxicity, and will permanently stop it if the reaction does not improve or worsens with a dose pause — this is a decision made and carried out by your care team, not something to self-manage. They will monitor for and treat dermatologic and soft-tissue toxicities, and watch for inflammatory or infectious complications.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1)
Infusion-related reactions may occur, especially during the first administration, and can be severe — serious
Symptoms: Infusion-related reactions may occur, especially during the first administration, and can be severe; monitor patients during and after infusion for signs of a reaction. Electrolyte disturbances (hypomagnesemia, hypokalemia, hypocalcemia) are common with prolonged use and require periodic monitoring during and for up to 8 weeks after the last dose. Ocular toxicities, including keratitis and ulcerative keratitis, have been reported and require prompt ophthalmologic evaluation for acute or worsening eye symptoms. Not effective — and not recommended — for tumors with RAS mutations (KRAS or NRAS) or unknown RAS status; RAS mutation testing is required before starting therapy.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1)
Contraindications recorded in the clinician database — serious
Symptoms: Contraindications recorded in the clinician database: Contraindicated in patients with known hypersensitivity to panitumumab or any excipients. Use with caution in patients with a history of severe skin disorders, electrolyte imbalances, or pre-existing ocular conditions. Not recommended in patients with RAS-mutant colorectal cancer, as efficacy is lacking. Monitor for infusion reactions, dermatologic toxicity, and electrolyte disturbances.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Recorded interactions | Panitumumab may interact with other cancer therapies and medications that affect electrolyte balance. Caution is advised when used with nephrotoxic agents or drugs that prolong QT interval. Always inform your healthcare provider about all medicines and supplements you are taking. | (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
Based on its mechanism (EGFR blockade) and animal data, panitumumab can cause fetal harm; the FDA label reviewed for this page advises females of reproductive potential to use effective contraception during treatment and for 2 months after the last dose. Panitumumab is not recommended during pregnancy; discuss any pregnancy or plan for pregnancy with the oncology team before starting or continuing treatment. (1)
Breastfeeding
The FDA label reviewed for this page states there is no data on the presence of panitumumab in human milk or its effects on a breastfed infant, but because human IgG is known to be present in milk, a risk to the infant cannot be excluded. Because of the potential for serious adverse reactions in a breastfed child, breastfeeding is not recommended during treatment and for 2 months after the final dose. (1)
Children
Frequency: Not applicable.. Weight Based: Not recommended for pediatric use.. Max Daily Dose: Not applicable.. Max Single Dose: Not applicable.. Age Restrictions: Safety not established in children. (1)
Renal_impairment
Per the FDA label reviewed for this page, no clinically significant differences in panitumumab pharmacokinetics were observed with mild or moderate renal impairment (creatinine clearance 30-89 mL/min) or mild or moderate hepatic impairment (total bilirubin up to 3x the upper limit of normal, any AST level); no dose adjustment is required in these groups. Panitumumab has not been studied in severe renal or hepatic impairment, so no dosing recommendation exists for those groups — use requires individualized oncology-team judgment. (1)
Hepatic_impairment
Per the FDA label reviewed for this page, no clinically significant differences in panitumumab pharmacokinetics were observed with mild or moderate renal impairment (creatinine clearance 30-89 mL/min) or mild or moderate hepatic impairment (total bilirubin up to 3x the upper limit of normal, any AST level); no dose adjustment is required in these groups. Panitumumab has not been studied in severe renal or hepatic impairment, so no dosing recommendation exists for those groups — use requires individualized oncology-team judgment. (1)
Monitoring
(1)Storage
Per the FDA label, store unopened vials in a refrigerator at 2-8 degrees C (36-46 degrees F) in the original carton to protect from light; do not freeze, and do not shake. Prepared infusion solutions should be used promptly or stored/handled per the healthcare facility's own stability protocol, consistent with the product label.
Professional information
Clinician-facing context only. This section does not replace current product labeling.
General
Indication: Metastatic colorectal cancer (mCRC) with wild-type RAS
Dose summary: 6 mg/kg administered as an intravenous infusion over 60 minutes every 14 days (subsequent infusions may be given over 30-60 minutes if the first is tolerated); doses of 1000 mg or lower are infused over 60 minutes per the FDA label.
Renal context: Per the FDA label, no dose adjustment is required for mild or moderate renal impairment (creatinine clearance 30-89 mL/min) — pharmacokinetics were not significantly different from patients with normal renal function. Panitumumab has not been studied in severe renal impairment. (1)
Frequently asked questions
What is panitumumab used for?
Panitumumab is used to treat metastatic colorectal cancer in adults whose tumors do not have RAS gene mutations. It is often used when other treatments have not worked or in combination with chemotherapy.
How does panitumumab work?
Panitumumab is a monoclonal antibody that blocks the epidermal growth factor receptor (EGFR) on cancer cells, slowing their growth and spread.
What are the most common side effects?
The most common side effects are skin rash, itching, dry skin, nail changes, diarrhea, and mild infusion reactions.
Can panitumumab be used in children?
Panitumumab is not routinely recommended for use in children, as safety and effectiveness have not been established in pediatric patients.
What should I do if I miss a dose?
Contact your healthcare provider as soon as possible to reschedule your infusion. Do not try to make up a missed dose on your own.
Are there any foods or activities I should avoid?
Avoid excessive sun exposure and use sunscreen, as panitumumab can make your skin more sensitive to sunlight. Also, avoid live vaccines during treatment.
Is genetic testing required before starting panitumumab?
Yes, genetic testing for RAS mutations is required. Panitumumab is only effective in patients with wild-type (non-mutated) RAS tumors.
What happens if I take too much Panitumumab?
If an overdose of Panitumumab is suspected, it is crucial to seek immediate emergency medical attention. While specific overdose symptoms may vary, potential adverse effects could be exacerbated. Healthcare providers will manage symptoms and provide supportive care to ensure patient safety and mitigate any severe reactions.
Can I drink alcohol while taking Panitumumab?
There is no direct contraindication for alcohol consumption with Panitumumab. However, as an antineoplastic agent, Panitumumab can cause side effects such as fatigue or gastrointestinal issues, which alcohol might worsen. It is always best to discuss alcohol intake with your healthcare provider to understand potential interactions and ensure your safety during treatment.
Is Panitumumab safe during pregnancy?
Panitumumab's pregnancy category requires careful consideration. It is generally not recommended during pregnancy due to potential risks to the fetus. Women of childbearing potential should use effective contraception during treatment and for a period after. Always consult your doctor to discuss the risks and benefits if you are pregnant or planning to become pregnant.
What is the mechanism of action of panitumumab?
Panitumumab is a fully human IgG2 monoclonal antibody that binds specifically to the extracellular domain of the epidermal growth factor receptor (EGFR). By blocking ligand-induced activation of EGFR, panitumumab inhibits downstream signaling pathways involved in cell proliferation, survival, angiogenesis, and metastasis. This leads to inhibition of tumor growth in cancers that are dependent on EGFR signaling, particularly in RAS wild-type colorectal cancer. (1)
What is the generic name of Panitumumab?
The generic name is panitumumab. It is sold under brand names including Panimab, Vectibix, Panitumab.
What class of drug is panitumumab?
Panitumumab is classed as: Monoclonal Antibody; Epidermal Growth Factor Receptor (EGFR) Inhibitor; Antineoplastic Agent.
References
- Vectibix (panitumumab) — prescribing informationU.S. Food and Drug Administration · United States · accessed 2026-08-07 · source 1
- Panitumumab Injection — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 2
- Vectibix — FDA approval record (Drugs@FDA BLA125147)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 3
- panitumumab — RxNorm normalized drug concept (RXCUI 263034)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 4
Brand names by country
Single-ingredient panitumumab names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Vectibix400 mg/20mL, 100 mg/5mL · amgen, inc
Canada
- VECTIBIX