rkrw, I don't have the data to determine how much sales need to occur before a valid statistical analysis could be performed.
The more rare the event, the larger the data population would need to be to glean any statistical differences between the two products.
And it is most likely a ocmplicated analysis, because outcomes are not going to be black and white. This is the sort of analysis I would do only if I worked for one of the companies and had access to the detailed patient outcomes. But I am sure analysts in both companies will be pouring over data from sales.
The more sales MNTA has, the more confidence the market will have that the products are identical.
take care