My husband is on cpt-11/avastin for his gbm. Our insurance did approve it to pay for it, but we were told that even if the insurance didn't, the pharmaceutical companies would probably agree to pay for the drugs, because they are wanting to get more gbm patients on it in order to see if it could be approved to treat this kind of cancer. Talk to your doctors and see if they can contact the pharm. companies to see about getting you the drug for free or at reduced cost.
I think there is also a clinical trial of these drugs that started at Duke University in May. Have been hearing lots of good results from it, and my husband's first check-up after having gone on it was great! Hope it works out well for you. Keep us posted.
Amanda