You could try using the Convert to new Sampler Track function. This will get you half way there. You will have the different slices of the loop mapped out across your keyboard, and you can sequence them in any way you like. But it won't remove the kick drum from your original loop. So, depending on how you want to alter the kick drum part; it'll work successfully to varying degrees.
If you want to add to the kick drum part that is already there you'll probably be fine. But if you really want to change ti up significantly; you'll have to deal with those original kick drum hits in the loop somehow.