No, and even if there was it's a UK resident tax law that makes them tax-free not the product themselves. For example even if he could open an account with say IG he'd still have to pay taxes on any profits.
The only option open to him is to get a trusted friend to open an account and then pass the profits on. Whoever does this for him should charge him at least 5% of profits. I would also not recommend wiring any profits to him in the US. He'd have to come and pick them up in cash. The IRS make the Inland Revenue look like your best friends.
Finspreads have an Italian site, which obviously is run under Italy's regulations. Or is it? Text is Italian but numbers are the same. Dear God, does that sound stupid? Yes. Anyway, not sure this helps, but it's: