What does crestor (rosuvastatin) do for lpa?

Not much. Treatment of elevated lp(a) is a bit tough. Potent statins can mitigate the risk by lowering the ldl-cholesterol level as much as possible (below 70 mg/dl), since that particle is tied to the ldl-c molecule. Estrogen therapy in women, Niacin in both sexes, and in the future, cholesterol ester transfer protein inhibitors (if they come to market) may lower lp(a) levels.