IMS data for generic drugs is not as useful for computing net sales as it is for brand drugs. IMS only shows gross sales dollars so a brand usually has the same discount percent for their entire customer base so you can figure net sales easy. With generics you have different net prices with your customers based on the contracts you struck to get them to write your product over the brands or another generic (not case since we are sole generic but may have not been able to adjust price upward once AG removed from market. MNTA does not know what deals sandoz gave it customers to write its product So MNTA needs to wait to get the net sales data from sandoz.
IMS really just shows unit trends. One other big difference is what IMS shows it is Units dispensed by a pharmacy not units sold to a pharmacy. So Sandoz records a sale in a quarter when they sell product to lets say CVS, IMS will reflect the sale when CVS sells the product to their customer the patient. So if CVS has a change in their inventory levels during a quarter then IMS units sold would be different then the units sandoz says they sold.