Does adding Erbitux to chemotherapy help people whose colorectal cancer has spread beyond the colon or rectum to distant body sites?
The answer is yes, according to a pooled analysis of two large randomized clinical trials comparing chemotherapy alone to chemotherapy plus Erbitux® (cetuximab). However, benefits depend on whether or not patient tumors have mutations of two genes, KRAS and BRAF.
Previous studies have shown that only patients with normal or wild type KRAS get any benefit from EGFR inhibitors Erbitux or Vectibix™ (panitumumab) so a combined analysis of the CRYSTAL and OPUS studies looked only a outcomes in KRAS wild type tumors. In addition, the research team studied the effect of mutations to BRAF.
They found that adding Erbitux to initial chemotherapy improved overall survival time, time until cancers got worse (progression-free survival), the percent of tumors that shrank with treatment (overall response rate) for tumors with wild-type KRAS. The best outcomes were in patients who had both wild-type KRAS and wild-type BRAF. Read the rest of this entry »