I have no idea what type of cancer King Charles III has, and I have no clue if DCVax-l will play a role in his treatment, but the BNN article on King Charles III with the picture of DCVax-l reminds of another former King of sorts that highlighted the effectiveness of Keytruda for metastatic melanoma.
About a decade ago, former President Jimmy Carter started the melanoma therapy Keytruda less than a year after it was approved. He was the unintended poster (grandpa) child that eventually helped launch Keytruda to the stratosphere.