My Herceptin is ordered 6 weeks at a time as that is when i see the onc. I call the pharmacy when I am on my way to Chicago...a 1 1/2 - 3 hour drive depending on traffic, and mine is ready for infusion when I get there...I know that they keep it in a drawer, light affects many chemo drugs,
I think the price has more to do with mixing it up ahead of time as it is so person specific and mixed according to weight.

I get my herceptin mixed once I'm at the hospital in the treatment room already hooked up in the chair. We usually have to wait for the on-site pharamcist to mix it.