It cannot be regulated and that's the whole point of Bitcoin, to be free from government regulation and manipulation. The value of Bitcoin has surged this high based on this one selling point alone.
Actually bitcoin is under regulation in other big countries now, but most of the countries are still just planning to do it but I think it will take some time to happen but there is a possibility it will happen soon.
I think this is a big advantages for people who invested on bitcoin and other cryptocurrency if happens that the government will regulate no more huge fluctuation that market may encounter.