I don't think the movie is a comedy, but it does have unintentional comedy in it as a result of the hammer you over the head with the message seriousness that tells the audience how to feel vs it happening genuinely. But that's part of it's charm in my opinion.
[Show spoiler]It's similar to Christian movies(like Pure Flix stuff) that over preach to the audience and beat the message into you vs allowing the viewers to come to their own conclusions. If only it were that simple in reality. But sometimes these simple black and white stories are a nice escape from reality if only real life worked that way.
And with the way the world is going today, with idiots not believing in global warming despite the evidence("Nothing to see here") and idiots trying to do good, but wind up causing more harm to nature like in the link below. I think it's ripe for a modern take on the story-line, and make it really disturbing, depressing/bleak and darkly amusing in an ironic way.
Oh and Prophecy does have some serious scares in it though. The opening sequence is very atmospheric, numerous bits throughout pack a punch, and the last half of the film has some terrifying suspenseful and well done set pieces.
But like I said, there is some unintentional humor in it mostly from the main actors William Shatner/Charlton Heston type of acting. He gives it his all, but some of his dialogue is too on the nose preachy as the screenwriter was trying to hammer home the message.
I can't wait for the release though! Since I do like the movie and can take it mostly seriously, but there are bits that just amuse me for reasons stated previously.
Oh, there was an It's Alive remake in the early/mid 2000's that was direct to video. I haven't seen it, but it was probably nothing special.
I haven't seen the 'It's Alive' remake either, but from what I gather they up'ed the gore and went with an R-rating. The original in PG form was nightmare inducing.