Patent Expiries Set To Drive Generics Boom

Retail sales of generic drugs in the world's top 10 markets will grow at a compound annual rate of 10% to $21 billion by the year 2000, forecasts IMS Pharma Strategy Group. This is double the 5% predicted annual retail growth rate during this period. Around 120 major branded drugs, with current sales of $20 billion, are expected to face generic competition by 2000, the study adds.

In 1993-95, a large number of original branded drugs faced patent expiry, notably Tagamet (cimetidine) and Naprosyn (naproxen sodium), which lost $150 million and $250 million respectively in brand sales in 1995. Within a year of patent expiry, 33% of cimetidine sales and 51% of naproxen sales were taken by generics. Selected forecasts by percentage of generic revenue are shown below:

% Generic Revenue ($) of Selected Molecules In 2000 Belgium Canada France Germany Italy Japan Neth Spain UK USA -------------------------------------------------------------------------- aciclovir 10 44 4 46 2 5 45 9 42 21 atenolol 0 69 2 36 5 17 56 5 21 48 captopril 5 57 2 20 2 22 24 3 27 32 cefaclor 0 51 7 73 4 34 12 4 3 25 diclofenac 20 37 10 62 3 15 66 4 27 30 diltiazem 0 10 6 55 4 2 20 3 65 23 fluoxetine 0 62 0 57 5 0 11 2 5 0 naproxen 14 23 0 37 4 11 63 2 52 80 omeprazole 0 24 0 32 0 0 0 4 10 13 piroxicam 0 66 10 56 5 22 37 3 22 48 ranitidine 19 85 2 83 2 1 31 4 25 31 -------------------------------------------------------------------------- Source: IMS Pharma Strategy Group