panitumumab

High Alert

Wild-type RAS (wild type in KRAS and NRAS) metastatic colorectal cancer that has failed fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy (as monotherapy).
Wild-type RAS (wild type in KRAS and NRAS) metastatic colorectal cancer (as first-line therapy with FOLFOX).
KRAS G12C-mutated metastatic colorectal cancer in patients who have received prior treatment with fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy (in combination with sotorasib).

Action ⬆ ⬇

Binds to epidermal growth factor receptor, resulting in inactivation of kinases that regulate proliferation and transformation.

Therapeutic effects:

Decreased progression of colorectal cancer.

Pharmacokinetics ⬆ ⬇

Absorption: IV administration results in complete bioavailability.

Distribution: Unknown.

Metabolism/Excretion: Unknown.

Half-Life: 7.5 days.

Time/Action Profile ⬆ ⬇

(plasma concentrations)

ROUTE	ONSET	PEAK	DURATION
IV	unknown	end of infusion	unknown

Contraind./Precautions ⬆ ⬇

Contraindicated in:

Concurrent use of leucovorin;
RAS: mutant metastatic colorectal cancer or unknown RAS mutation status (↑ mortality and tumor progression);
OB: Pregnancy;
Lactation: Lactation.

Use Cautiously in:

Rep: Women of reproductive potential;
Pedi: Safety and effectiveness not established in children.

Adv. Reactions/Side Effects ⬆ ⬇

CV: edema

Derm: acneiform dermatitis, dry skin, erythema, paronychia, pruritus, rash, skin exfoliation, skin fissures, abscesses, NECROTIZING FASCIITIS, photosensitivity

EENT: corneal perforation, eyelash growth, keratitis, ulcerative keratitis

F and E: hypomagnesemia, hypocalcemia

GI: abdominal pain, constipation, diarrhea, nausea, vomiting, stomatitis

GU: acute renal failure

Neuro: fatigue

Resp: cough, INTERSTITIAL LUNG DISEASE (ILD), PULMONARY FIBROSIS

Misc: INFUSION REACTIONS

Interactions ⬆ ⬇

Drug-drug:

None reported.

Route/Dosage ⬆ ⬇

RAS Wild-Type Metastatic Colorectal Cancer

IV (Adults ): 6 mg/kg every 14 days; continue until disease progression or unacceptable toxicity.

KRAS G12C: Mutated Metastatic Colorectal Cancer

IV (Adults ): 6 mg/kg every 14 days; continue until disease progression, unacceptable toxicity, or until sotorasib is withheld or discontinued. Administer 1st sotorasib dose before 1st panitumumab infusion.

Availability ⬆ ⬇

Solution for injection: 20 mg/mL

Assessment ⬆ ⬇

Assess for dermatologic toxicity (dermatitis acneiform, pruritus, erythema, rash, skin exfoliation, paronychia, dry skin, skin fissures). If severe, may lead to infection (sepsis, septic death, abscesses requiring incision and drainage). Upon 1st occurrence of Grade 3 dermatologic toxicity, hold 1–2 doses; if skin improves to Grade <3, resume at original dose. For 2nd occurrence of Grade 3 dermatologic toxicity, hold 1–2 doses; if skin improves to Grade <3, resume at 80% of original dose. For 3rd occurrence of Grade 3 dermatologic toxicity, hold 1–2 doses; if skin improves to Grade <3, resume at 60% of original dose. For Grade 4 dermatologic toxicity or 4th occurrence of a Grade 3 dermatologic toxicity, permanently discontinue panitumumab.
Monitor for signs/symptoms of infusion-related reactions (fever, chills, hypotension, dizziness, nausea, vomiting, urticaria, pruritus, shortness of breath, bronchospasm, angioedema) during and within 24 hr of infusion. If mild to moderate infusion-related reaction occurs,↓ infusion rate by 50%. If severe infusion-related reaction occurs, stop panitumumab; may require permanent discontinuation.
Monitor for signs/symptoms of ILD or pulmonary fibrosis (dyspnea, cough, hypoxia, fever). CT scan or chest x-ray can confirm. If ILD or pulmonary fibrosis suspected, hold therapy. If ILD or pulmonary fibrosis confirmed, permanently discontinue panitumumab.
Monitor for diarrhea and dehydration during therapy. Provide supportive care including antiemetic or antidiarrheal as needed; hold panitumumab, if necessary.
Monitor for evidence of keratitis, ulcerative keratitis, or corneal perforation. If acute or worsening keratitis, ulcerative keratitis, or corneal perforation occur, interrupt or discontinue panitumumab.

Lab Test Considerations:

Patient selection is based on RAS or KRAS G12C status. Prior to administration, assess RAS and KRAS G12C mutational status in colorectal tumors and confirm the absence of a RAS mutation in exons 2, 3, and 4. Information on FDA-approved tests for the detection of RAS and KRAS G12Cmutations in patients with metastatic colorectal cancer is available at http://www.fda.gov/CompanionDiagnostics.
Monitor electrolytes regularly during and for 8 wk after therapy. May cause hypomagnesemia, hypocalcemia, and hypokalemia. Replace electrolytes as needed.

Implementation ⬆ ⬇

Intermittent Infusion: Diluent: Dilute dose in 100 mL of 0.9% NaCl; dilute doses >1000 mg with 150 mL. Concentration: 10 mg/mL. Mix by inverting gently; do not shake. Solution is colorless and may contain a small amount of visible translucent to white, amorphous, proteinaceous particles. Do not administer solutions that are discolored or contain particulate matter. Store in refrigerator; do not freeze. Use diluted solution within 6 hr of preparation if stored at room temperature or within 24 hr if refrigerated.
Rate: Administer over 60 min via infusion pump using a low-protein-binding 0.2-mcg or 0.22-mcg in-line filter. If 1st infusion is tolerated, subsequent infusions may be infused over 30–60 min. Administer doses >1000 mg over 90 min. Flush line before and after administration with 0.9% NaCl.
Y-Site Incompatibility: Do not administer other drugs through same IV line.

Patient/Family Teaching ⬆ ⬇

Explain purpose and side effects of panitumumab. If an appointment is missed, reschedule as soon as possible. Advise patient to read Patient Information before starting and with each Rx refill in case of changes.
Emphasize the importance of regular follow-ups and eye exams to monitor for side effects and periodic blood tests to monitor electrolyte levels.
May cause photosensitivity. Caution patient to wear sunscreen and hats and to limit sun exposure. Advise patient to avoid tanning beds during treatment and for 2 mo following therapy, as sunlight may ↑ risk of dermatologic reactions.
Instruct patient to report symptoms of hypomagnesemia, hypocalcemia, or hypokalemia (muscle twitches, spasms, weakness, or cramps; heart palpitations).
Advise patient to notify health care provider if signs and symptoms of dermatologic toxicity, infusion reactions, pulmonary fibrosis, or ocular changes occur.
Advise patient to notify health care provider of all Rx or OTC medications, vitamins, or herbal products being taken and to consult with health care provider before taking other medications.
Rep: May cause fetal harm. Advise women of reproductive potential to notify health care provider if pregnancy is planned or suspected or if breastfeeding. Advise women of reproductive potential to use effective contraception and to avoid breastfeeding during therapy and for 2 mo after last dose. May impair fertility in women.

Evaluation/Desired Outcomes ⬆ ⬇

Decreased progression of colorectal cancer.

US Brand Names ⬆ ⬇

Code ⬆

NDC Code

55513- Amgen Inc
- 55513-954- Vectibix
  - 55513-954-01- 1 VIAL, SINGLE-DOSE in 1 CARTON (55513-954-01) / 5 mL in 1 VIAL, SINGLE-DOSE

55513- Amgen Inc
- 55513-954- Vectibix
  - 55513-954-21- 1 VIAL, SINGLE-DOSE in 1 CARTON (55513-954-21) / 5 mL in 1 VIAL, SINGLE-DOSE

55513- Amgen Inc
- 55513-956- Vectibix
  - 55513-956-01- 1 VIAL, SINGLE-DOSE in 1 CARTON (55513-956-01) / 20 mL in 1 VIAL, SINGLE-DOSE

55513- Amgen Inc
- 55513-956- Vectibix
  - 55513-956-21- 1 VIAL, SINGLE-DOSE in 1 CARTON (55513-956-21) / 20 mL in 1 VIAL, SINGLE-DOSE

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Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇