A 10,000 year old alien takes human form and becomes a super powerful paraplegic in his attempt to save the Earth from destruction.

Ok try this version:

Visiting Earth to save it from destruction an Alien has a near fatal accident after which he develops super human powers as a paraplegic.
cheers
GG

Good idea to leave out the bio-spiritual disease part.
As the logline reads at present the alien chooses to be paraplegic. I have to ask this, why choose to be paraplegic? I'm mentally and physically disabled and understanding why anyone (or any alien) would choose to become disabled is beyond me.
So, could that part be reworded?
Is there any need to state how old the alien is?
Who causes the bio-spiritual disease in the first place, is there a reason for causing it?
Mention the word spiritual and folk will think of the church, rightly or wrongly.
They are not questions to be answered, merely points to consider when thinking of a logline, making it appeal to the few (producers) who want lots of money, bums on seats, box office receipts.
Mention paraplegic, coupled with saving the earth and an X-Men type scenario comes to mind.
I have no problems with that, but some folk may.

Point taken - from self destruction through the spread of bio-spiritual diseases.