Panitumumab (Vectibix): serious hypersensitivity reactions

New reports of serious hypersensitivity reactions (including anaphylaxis) in patients receiving panitumumab, some of which were fatal.

Article date: May 2010

Panitumumab (Vectibix) is indicated as monotherapy for the treatment of patients with EGFR (epidermal growth factor receptor)-expressing metastatic colorectal carcinoma with non-mutated (wild type) KRAS after failure of chemotherapy regimens.

There have been new reports of serious hypersensitivity reactions (including anaphylaxis) in patients receiving panitumumab, some of which were fatal.

A clinical trial report has been received of a fatal case of angioedema occurring 2 days after exposure following a prior episode of angioedema which occurred 6 days after exposure. Recently, two case reports of fatal hypersensitivity reactions during and immediately following panitumumab infusion have been received; these patients had previously experienced hypersensitivity reactions to cetuximab and oxaliplatin, respectively.

Advice for healthcare professionals

Panitumumab is contraindicated in patients with a history of severe or life-threatening hypersensitivity reactions to this medicine.
Serious infusion-related reactions are unpredictable and can occur suddenly. Panitumumab should be permanently discontinued if a severe or life-threatening reaction occurs.
In patients with a mild or moderate infusion-related reaction, the infusion rate should be reduced for the duration of the infusion; it is recommended to maintain this lower infusion rate in all subsequent infusions.
Hypersensitivity reactions occurring more than 24 hours after infusion have also been reported. Patients should be warned of a possible late-onset reaction and instructed to contact their physician if symptoms of hypersensitivity occur.

A letter has been sent to relevant healthcare professionals to inform of these risks.

Article citation: Drug Safety Update May 2010, vol 3 issue 10: 8.

Published 11 December 2014