An improvement in survival has been demonstrated for patients with advanced non-small cell lung cancer treated with Merck KGaA’s EGFR-targeting monoclonal antibody therapy Erbitux in addition to chemotherapy.

Patients on Erbitux (cetuximab), in a study reported at the joint European Cancer Organisation/ European Society of Medical Oncology (ECCO-ESMO) meeting in Berlin, were 13% less likely to die than those receiving chemotherapy alone, regardless of which chemotherapy drug cocktail was used. They also experienced slower disease progression and an increased chance of tumour shrinkage.

The finding came from a meta-analysis of four trials investigating first-line cetuximab added to various platinum-based chemotherapies, which included a total of 2,018 patients. “We found that patients who got cetuximab had a 13% lower chance of dying within the three years of follow-up compared with those who got chemotherapy alone,” said Professor Jean-Louis Pujol, chair of thoracic oncology at Montpelier Academic Hospital and professor of medicine at Montpelier University in France.

“For lung cancer, considering that this disease is very resistant to treatment and that the prognosis is very poor, an improvement of that magnitude is meaningful," he added. "It’s about the same as what you get from giving chemotherapy after surgery and that’s accepted as standard treatment.”

Median survival was 9.4 months in the chemotherapy alone group and 10.3 months in the chemotherapy plus cetuximab group. The meta-analysis also revealed a 10% improvement in progression free survival and found that patients who received Erbitux along with their chemotherapy were 48% more likely to experience tumour shrinkage. Quoted in a news release issued by ECCO-ESMO, Prof Pujol said that fewer than 30% of patients with advanced NSCLC respond to chemotherapy. Adding Erbitux pushes the response rate up to about 45%. Benefits were seen across all subtypes of the disease.

Lung cancer is the leading cause of cancer death worldwide, killing an estimated 1.31 million people a year. NSCLC, which usually expresses EGFR, the target for Erbitux, accounts for about 80% of cases. Patients with advanced disease have had few treatment options and about 70% die within a year of diagnosis and fewer than 2% survive five years. Platinum-based chemotherapy is the current standard treatment.

Studies of other EGFR blockers which act differently to Erbitux have not shown benefit when combined with chemotherapy in first-line treatment of advanced NSCLC, although they have done in second-line treatment. Erbitux may have an advantage because it blocks the EGF receptor in a different location.

“We now have enough evidence to recommend cetuximab for patients with advanced NSCLC and we have confirmation that it doesn’t matter what kind of chemotherapy it is used with,” Prof Pujol said. “What we now need to investigate is whether this drug could also help at early stages of the disease.”

Erbitux will also feature at ECCO-ESMO in the UK Medical Research Council’s COIN trial, involving 1,630 patients, investigating whether adding the drug to oxaliplatin chemotherapy improves overall survival in metastatic colorectal cancer (mCRC) patients with when given as first-line therapy. Results, to be disclosed by Professor Tim Maughan of Cardiff University, will be available Wednesday. Further data are also expected from the CRYSTAL and OPUS trials of first-line Erbitux treatment plus chemotherapy in mCRC.

An update will show the impact of Erbitux on overall survival in patients with and without KRAS wild type tumours. KRAS status is now a recognised predictive biomarker for response to EGFR targeting therapies like Erbitux and Vectibix (panitumumab) in colon cancer. Prior KRAS testing is increasingly regarded as a mandatory prerequisite before prescribing EGFR inhibitors for mCRC. By Olwen Glynn Owen in Berlin