The option does not exist in Italy because the tax is a property tax, not a road tax. You have to pay it even if the car is off the road for the whole year. However historic vehicles (over 20years) are exempt and only pay a road tax of €30.
The cost of insurance of historic vehicles is also much reduced. For newer vehicles it is possible to insure them for only 6 months or to suspend the insurance for up to 6 months. Many motorcyclists take that option.