John McCain is over 80 if I recall. His therapy might require a combination due to a very likely depleted immune system from GBM and age. After chemoradiation, he might be looking at something individual and highly experimental.
If I were in his shoes and had his resources, I'd personally try intradermal DCVax-L + low dose regionally administered Opdivo or Keytruda + oral PLX-3397. (Probably starting a couple days early with oral PLX-3397 then adding DCVax-L then a few days later starting Opdivo or Keytruda as well.) One of the major tricks will be managing initial and possible latent swelling. This is all just my opinion.
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