If the currently-available treatments mean I'm going to die, "try something that might kill me or cure me" is absolutely a thing I would consider "to save my life".
The clinical trial might very well shorten your life and/or make your quality of life worse. It might not only not save your life, but it might be the case that not joining the clinical trial saves your life (at least for a little while longer).
Yeah, but unfortunately rhat makes you a really bad clinical subject in any trial.
Unfortunately, by the time most people reach the "no hope" stage, the disease has processed to the point where no intervention would help.
Conversely most interventions work best at the "early detection" phase. Which (ironically) is when you're best off with proven stuff, not new experimental stuff.
This catch-22 is precisely why its so hard to get improvements in this field.