Would I take Tasigna (nilotinib) on an off-label basis?

Good question.

No. The weakness of the clinical trial results and the high price of nilotinib would stop me from using it.

Price affects me in two ways: the direct effect, I can't afford it, and an indirect effect, I have less confidence in results that come from trials of therapies which have a large profit potential.

The phase 1 clinical trial described by PDF [1] was small (12 participants). It may be just bad luck, but one participant had a heart attack, which PDF describes as "a known potential side effect of the drug". The results were not outstanding:
"... seven of the 12 did show some benefit. When all study participants were considered, the average improvement was between three to four points on a commonly used rating scale (approximately an eight percent improvement), while a five point change is generally viewed as the minimal improvement to make a difference in PD."

Reference:

[1] "Cancer Drug Shows Evidence of Safety for Parkinson’s"
Parkinson's Disease Foundation- Jul 11 2016
Cancer Drug Shows Evidence of Safety for Parkinson’s - Parkinson's Disease Foundation (PDF)

John