Amgen has presented data for Vectibix and the investigational compound denosumab at the joint European Cancer Organisation/European Society of Medical Oncology (ECCO-ESMO) meeting in Berlin.

Starting with Vectibix (panitumumab), the company presented data from the Phase III '181' trial evaluating the drug in combination with FOLFIRI (an irinotecan based chemotherapy), as a second-line treatment for metastatic colorectal cancer (mCRC). The findings revealed that the combo significantly improved progression-free survival in patients with KRAS wild-type mCRC by two months to 5.9 months compared to 3.9 months for those on FOLFIRI alone.

However the study also revealed that there was no significant difference in median overall survival but there was a “greater than a three-fold improvement” in the tumour response rate in patients on Vectibix/FOLFIRI combination (35% versus 10%).

Marc Peeters of the University Hospital Ghent in Belgium and the study's principal investigator, said the trial showed that Vectibix can be safely administered in combination with FOLFIRI and delayed disease progression by more than half compared to chemotherapy alone in patients with previously-treated KRAS wild-type colorectal cancer. Furthermore, “the response rate seen in this trial is among the highest ever reported in the second-line mCRC setting,” he added.

Amgen is hoping that Vectibix can make serious inroads into the anti-EGFR market which is dominated by Merck KGaA/Bristol-Myers Squibb/Eli Lilly’s Erbitux (cetuximab).

Denosumab/Zometa trial
The company also presented data on denosumab which showed that the much-touted experimental drug delayed skeletal-related events (SREs) in advanced cancer patients with bone metastases.

Specifically, the 1,776-patient trial revealed that the median time to the first SRE, ie fracture, radiation to bone, surgery to bone, or spinal cord compression, was 20.6 months for those patients on denosumab and 16.3 months for those on Novartis’ Zometa (zoledronic acid), enough to establish non-inferiority. Amgen noted, however, that although numerically greater, the delay in the time to first or first-to-subsequent SRE associated with denosumab was not statistically superior compared to Zometa.

Amgen quoted David Henry, clinical professor of medicine at the Pennsylvania Hospital, as saying that “it is encouraging to see denosumab's efficacy in this broad cancer population [and] there is no need for renal monitoring or dose adjustments due to renal impairment". He added that the results of the trial, “combined with the convenience of a monthly subcutaneous injection and without the flu-like symptoms associated with Zometa administration, make this an exciting potential treatment option for advanced cancer patients”.