CMS has posted the first quarter 2010 Medicare Part B drug Average Sales Price (ASP) amounts. CMS notes that average drug prices for the first quarter of 2010 generally remain stable compared to fourth quarter 2009 prices. In fact, prices for the top Part B drugs decreased by an average of 1.1 percent, with prices for the majority of the higher-volume drugs changing 2 percent or less. CMS attributes the decreases in the top drugs to a number of competitive market factors, such as multiple manufacturers, alternative therapies, new products, recent generic entrants, or market shifts to lower-priced products.