THE ENDURING LEGACY OF VECTIBIX®

Progress in the treatment of metastatic colorectal cancer, or mCRC, has been a journey of incremental gains.³

For more than two decades, the Vectibix® story has evolved alongside advances in biomarker science and a growing understanding of the clinical relevance of tumor sidedness.^4-6

Up until the early 2000s, treatment for mCRC relied predominantly on cytotoxic chemotherapy.⁷

VEGF- and EGFR-directed biologics expanded mCRC care beyond chemotherapy alone, establishing targeted therapy as part of systemic treatment.^8,9

The introduction of targeted biologics marked the beginning of this approach in clinical practice.^7,9,11

Vectibix® entered the treatment landscape in 2006 as one of the first anti-EGFR monoclonal antibody treatments¹⁰…

…approved for mCRC, offering another targeted option for patients who had progressed after prior treatment with fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy.¹⁰

In just a few years, the pace of precision accelerated.

Pivotal data from the PRIME trial, published in 2010, established KRAS biomarker testing as essential for informing first-line treatment selection for Vectibix®¹²…

…and was followed by extended RAS analysis in 2013 that further characterized comprehensive RAS status, including KRAS and NRAS.¹³

These findings contributed to the evolving understanding of comprehensive RAS biomarker assessment in metastatic colorectal cancer.¹³

By 2014, evidence supported the first approval for Vectibix® in combination with FOLFOX in the first-line setting for patients with wild-type KRAS mCRC.¹⁴

In 2017, the Vectibix® label was updated to include wild-type RAS, aligning the indication with extended molecular evidence.¹⁵

Together, these approvals signified the importance of patient biomarker testing at diagnosis to inform appropriate treatment selection.¹⁵

In 2019, NCCN Guidelines further refined 1L anti-EGFR therapy recommendations by adding BRAF wild-type status to existing biomarker and tumor sidedness criteria, reinforcing a biomarker-driven approach to patient selection in mCRC, one that continued to be reflected across major oncology guidelines.^16-18

In 2022, the PARADIGM study provided the first prospective evidence evaluating primary tumor sidedness in combination with RAS status in first-line anti-EGFR therapy for metastatic colorectal cancer.¹⁹

That same year, ASCO referenced the PARADIGM data in support of its recommendation of first-line anti-EGFR therapy plus doublet chemotherapy for patients with left-sided, wild-type RAS metastatic colorectal cancer.¹⁷

Precision medicine continued to hit its stride with multigene testing and targeted combination strategies.

A 2024 post hoc analysis of PARADIGM looked at the impact of BRAF, MSI-H, and tumor sidedness on first-line WT RAS treatment.⁴

This evolution toward hyperselection has expanded the understanding of the molecular landscape of metastatic colorectal cancer.⁴

In 2025, Vectibix® expanded into a new biomarker-defined population with its FDA approval in combination with a KRAS G12C inhibitor for adult patients with previously treated KRAS G12C-mutated mCRC.²⁰

This evolution in the understanding of mCRC, including tumor sidedness and biomarker assessment, marks an important milestone in the scientific understanding of the disease.

2026 marks 20 years of Vectibix®, with over 600,000 patients served worldwide.^1,2

At Amgen, we are committed to targeted treatment research. With Vectibix, we continue to build on more than two decades of research in metastatic colorectal cancer. With it comes the resolve to support patients with mCRC today and into the future.

Vectibix® can cause dermatologic toxicity, which may be severe.  Clinical manifestations included, but were  not limited to, acneiform dermatitis, pruritus, erythema, rash, skin exfoliation, paronychia, dry skin, and skin fissures.

Among 229 patients who received Vectibix® as monotherapy, dermatologic toxicity occurred in 90% including Grade 3 (15%). Among 585 patients who received Vectibix® in combination with FOLFOX, dermatologic toxicity occurred in 96% including Grade 4 (1%) and Grade 3 (32%). In 126 patients receiving Vectibix® in combination with sotorasib across clinical studies, dermatologic toxicities occurred in 94%, including Grade 3 (16%) of patients.

Monitor patients who develop dermatologic or soft tissue toxicities while receiving Vectibix® for the development of inflammatory or infectious sequelae. Life-threatening and fatal infectious complications including necrotizing fasciitis, abscesses, and sepsis have been observed in patients treated with Vectibix®. Life-threatening and fatal bullous mucocutaneous disease with blisters, erosions, and skin sloughing has also been observed in patients treated with Vectibix®. It could not be determined whether these mucocutaneous adverse reactions were directly related to EGFR inhibition or to idiosyncratic immune-related effects (eg, Stevens Johnson syndrome or toxic epidermal necrolysis). Withhold or discontinue Vectibix® for dermatologic or soft tissue toxicity associated with severe or life-threatening inflammatory or infectious complications. Dose modifications for Vectibix® concerning dermatologic toxicity are provided [see Dosage and Administration (2.3)].

Vectibix® monotherapy or in combination with oxaliplatin-based chemotherapy is not indicated for the treatment of patients with colorectal cancer that harbor somatic RAS mutations in exon 2 (codons 12 and 13), exon 3 (codons 59 and 61), and exon 4 (codons 117 and 146) of either KRAS or NRAS and hereafter is referred to as “RAS.”

Retrospective subset analyses across several randomized clinical trials were conducted to investigate the role of mutations on the clinical effects of anti-EGFR-directed monoclonal antibodies (panitumumab or cetuximab). Anti- EGFR antibodies in patients with tumors containing RAS mutations resulted in exposing those patients to anti-EGFR related adverse reactions without clinical benefit from these agents. Additionally, in Study 20050203, 272 patients with RAS-mutant mCRC tumors received Vectibix® in combination with FOLFOX and 276 patients received FOLFOX alone. In an exploratory subgroup analysis, OS was shorter (HR = 1.21,95% CI: 1.01-1.45) in patients with RAS-mutant mCRC who received Vectibix® and FOLFOX versus FOLFOX alone.

Vectibix® can cause progressively decreasing serum magnesium levels leading to severe (Grade 3 or 4) hypomagnesemia. Among 229 patients who received Vectibix® as monotherapy, hypomagnesemia occurred in 38% including Grade 4 (1.3%) and Grade 3 (2.6%). Among 585 patients who received Vectibix® in combination with FOLFOX, hypomagnesemia occurred in 51% including Grade 4 (5%) and Grade 3 (6%). In 126 patients receiving Vectibix® in combination with sotorasib across clinical studies, decreased magnesium occurred in 69%, including Grade 4 (2.4%) and Grade 3 (14%).

Monitor patients for hypomagnesemia and hypocalcemia prior to initiating Vectibix® treatment, periodically during Vectibix® treatment, and for up to 8 weeks after the completion of treatment. Other electrolyte disturbances, including hypokalemia, have also been observed. Replete magnesium and other electrolytes as appropriate.

In Study 20020408, 4% of patients experienced infusion reactions and 1% of patients experienced severe infusion reactions (NCI-CTC Grade 3-4). Infusion reactions, manifesting as fever, chills, dyspnea, bronchospasm, and hypotension, can occur following Vectibix® administration. Fatal infusion reactions occurred in postmarketing experience. Terminate the infusion for severe infusion reactions.

Severe diarrhea and dehydration, leading to acute renal failure and other complications, have been observed in patients treated with Vectibix®. Among 229 patients who received Vectibix® as monotherapy, acute renal failure occurred in 2% including Grades 3 or 4 (2%). Among 585 patients who received Vectibix® in combination with FOLFOX, acute renal failure occurred in 2% including Grade 3 or 4 (2%). In 126 patients receiving Vectibix® in combination with sotorasib across clinical studies, acute renal failure occurred in 3.2%, including Grade 3 (0.8%). Monitor patients for diarrhea and dehydration, provide supportive care (including anti-emetic or anti-diarrheal therapy) as needed, and withhold Vectibix® if necessary.

Fatal and nonfatal cases of interstitial lung disease (ILD) (1%) and pulmonary fibrosis have been observed in patients treated with Vectibix®. Pulmonary fibrosis occurred in less than 1% (2/1467) of patients enrolled in clinical studies of Vectibix®. Grade 1 ILD/pneumonitis occurred in 0.8% (1/126) of patients enrolled in clinical studies of Vectibix® in combination with sotorasib. In the event of acute onset or worsening of pulmonary symptoms interrupt Vectibix® therapy. Discontinue Vectibix® therapy if ILD is confirmed.

In patients with a history of interstitial pneumonitis or pulmonary fibrosis, or evidence of interstitial pneumonitis or pulmonary fibrosis, the benefits of therapy with Vectibix® versus the risk of pulmonary complications must be carefully considered.

Exposure to sunlight can exacerbate dermatologic toxicity. Advise patients to wear sunscreen and hats and limit sun exposure while receiving Vectibix®.

Serious cases of keratitis, ulcerative keratitis, and corneal perforation have occurred with Vectibix® use. Among 585 patients who received Vectibix® in combination with FOLFOX, keratitis occurred in 0.3%. In 126 patients receiving Vectibix® in combination with sotorasib across clinical studies, keratitis occurred in 1.6%, ulcerative keratitis occurred in 0.8%, and vernal keratoconjunctivitis in 0.8% (all were Grade 1-2). Monitor for evidence of keratitis, ulcerative keratitis, or corneal perforation. Interrupt or discontinue Vectibix® therapy for acute or worsening keratitis, ulcerative keratitis, or corneal perforation.

In an interim analysis of an open-label, multicenter, randomized clinical trial in the first-line setting in patients with mCRC, the addition of Vectibix® to the combination of bevacizumab and chemotherapy resulted in decreased OS and increased incidence of NCI-CTC Grade 3-5 (87% vs 72%) adverse reactions. NCI-CTC Grade 3-4 adverse reactions occurring at a higher rate in Vectibix-treated patients included rash/acneiform dermatitis (26% vs 1%), diarrhea (23% vs 12%), dehydration (16% vs 5%), primarily occurring in patients with diarrhea, hypokalemia (10% vs 4%), stomatitis/mucositis (4% vs <1%), and hypomagnesemia (4% vs 0%). NCI-CTC Grade 3-5 pulmonary embolism occurred at a higher rate in Vectibix-treated patients (7% vs 3%) and included fatal events in three (<1%) Vectibix-treated patients.

As a result of the toxicities experienced, patients randomized to Vectibix®, bevacizumab, and chemotherapy received a lower mean relative dose intensity of each chemotherapeutic agent (oxaliplatin, irinotecan, bolus 5-FU, and/or infusional 5-FU) over the first 24 weeks on study compared with those randomized to bevacizumab and chemotherapy.

Based on data from animal studies and its mechanism of action, Vectibix® can cause fetal harm when administered to a pregnant woman.  When given during organogenesis, panitumumab administration resulted in embryolethality in cynomolgus monkeys at exposures approximately 1.25 to 5 times the recommended human dose.  Advise pregnant women and females of reproductive potential of the potential risk to the fetus.  Advise females of reproductive potential to use effective contraception during treatment, and for at least 2 months after the last dose of Vectibix®.

In monotherapy, the most commonly reported adverse reactions (≥ 20%) in patients with Vectibix® were skin rash with variable presentations, paronychia, fatigue, nausea, and diarrhea.

The most commonly reported adverse reactions (≥ 20%) with Vectibix® + FOLFOX were diarrhea, stomatitis, mucosal inflammation, asthenia, paronychia, anorexia, hypomagnesemia, hypokalemia, rash, acneiform dermatitis, pruritus, and dry skin. Serious adverse reactions (≥ 2% difference between treatment arms) were diarrhea and dehydration.

Please see Vectibix® full Prescribing Information, including Boxed WARNING, at vectibixHCP.com.