It would make sense that Erbitux not be given a 2nd time if it didn't work the first time. I have heard of patients having Erbitux be given it as adjunctive treatment, after definitive treatment, for an extensive period of time, 6 months, a year as maintenance treatment or as inductive treatment in a cocktail before definitive treatment, possibly with Erbitux. Many other chemo's are usually not given again due to the possibility of one becoming chemo resistant to it, so a different or similar one is given.

Erbitux, initially a colorectal drug, I believe was initially approved for metastic head and neck cancer after prior treatment with and failure with a platinum based therapy. It was later it was approved as first line definitive treatment. .

They say about 5% of head and neck cancer patients have a mutated KRAS gene whereby Erbitux does not work, but there is no assay for this unlike there is for colorectal cancer, which mutation is as high as 40%.

I had Erbitux once, along with Taxotere, radiation, and it did not work in the long run, so I wasn't given it again.

Good luck