Fred- Those prescription numbers you posted also include the standard Seroquel prescription as well as the XR. The standard prescriptions still far exceed the XR ones.
I suppose it has only XR:
"According to Symphony Health Solutions, sales of Seroquel XR
® were approximately US$1.1 billion
for the 12 months ending January 2017 (TRx MBS Dollars)." http://www.intellipharmaceutics.com/product-detail.cfm?productID=118884
300k weekly prescriptions would make some US$1.5 billion sales if one prescription made US$100 sales.
I think there is really enough room for MNK sales, but do they take it seriously?