educated guess is the company doesn't want any bad outcomes in their trials,
2 things here:
1) this girl isn't in the trial, because the drug isn't actually designed for her situation (this is why she doesn't meet the requirements for the trial).
2) maybe you're saying she doesn't fit the trial, and that's wrong because she is sick. Let's look at this a little more objectively from the drug maker's point of view:
You have a drug for low back pain. It works outstanding for low back pain that's neurological in nature. This person wants your drug to work for their headache- lots of headaches are neurological in nature too (though not all). Would you want to include the person with headaches and no low back pain in your low back pain trial? The way medicines work, you really wouldn't want to. If, during the process, they find out that headaches happen to be relieved too, by a similar mechanism, then doctors will look at the way the drug works and decide to use it 'off-label' for headaches as well, because it would cost millions of dollars for the drug company to do a trial specifically for headaches after.
Similarly, in this case, this woman doesn't qualify based on the kind and staging of her cancer, so she does not qualify for the trial. Is it sad that she doesn't qualify? Sure. Anytime someone dies before they accept and are comfortable with the fact that death is the inevitable end to life, it saddens me greatly. But in this case, the outroar is because she is pretty. The FDA and drug company are both in the right in their decisions in this sad, sad case.