Vectibix Non-Inferior in Overall Survival with Colorectal Cancer

Amgen announced results from the Phase 3 ASPECCT (‘763) trial comparing Vectibix (panitumumab) to Erbitux (cetuximab; Bristol-Myers Squibb) for the treatment of wild-type KRAS metastatic colorectal cancer in patients who have not responded to chemotherapy.

ASPECCT is a global, randomized, multicenter, open-label, Phase 3 non-inferiority trial designed to compare the effect of panitumumab vs. cetuximab on overall survival for monotherapy treatment of chemorefractory metastatic colorectal cancer (mCRC) in 999 patients with wild-type KRAS tumors.

Patients were randomized in a 1:1 ratio to receive 6mg/kg of intravenous panitumumab every 14 days or 400mg/m2 of an initial dose of intravenous cetuximab, followed by 250mg/m2 of intravenous cetuximab every seven days.

The study met its primary endpoint, demonstrating that panitumumab was non-inferior to cetuximab for overall survival. The prospective study showed that the median overall survival for patients treated with panitumumab was 10.4 months (Range: 9.4–11.6 months) compared to 10 months (Range: 9.3–11.0 months) for patients treated with cetuximab (95% CI, 0.84–1.11, P=0.0007).

In the study, progression-free survival was a median of 4.1 months in patients treated with panitumumab vs. 4.4 months in patients treated with cetuximab (HR=1.00, 95% CI, 0.88, 1.14). Objective response rate, which is the percentage of patients who experienced tumor size reduction, was 22% for patients treated with panitumumab compared to 19.8% for patients in the cetuximab arm (Odds Ratio 1.15, 95%CI, 0.83, 1.58).

Vectibix is the first fully human anti-EGFR antibody already approved as a monotherapy for the treatment of patients with EGFR-expressing mCRC after disease progression on or following fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy regimens.

For more information call (800) 77-AMGEN or visit