Here's a comment with at least a summary of the novel better than I could manage (once, twice):
A trailer aired on the website for the film does look quite spectacular, but then French sci-fi has always tended to look flashy, "le cinéma du look", as it's called, without caring too much about the details of plot or plausibility.
But it could work out. La possibilité d'une île, described in the TLS as "a bracing mix of visionary Aldous Huxley, Evelyn Waugh at his cruellest, and ranting John Osborne", is about cloning as a way of cheating death, and is audacious in the way that it seeks to modify the author's extraordinary misanthropy by linking itself, apparently unironically, with a loopy cult who recall, but for legal reasons are not to be identified with, the Raëlians.
I, for one, can't wait.