able to achieve tremendous sales and profits from these drugs. For instance, Burroughs-Welcome successfully obtained a patent on AZT in 1988 and consequently gained exclusive rights to AZT as a treatment for HIV/AIDS until 2005.30 Burroughs-Welcome, which had been marketing AZT before the patent was ultimately approved, enjoyed sales of $158 million from AZT in 1988, with a one-year supply of AZT for one person selling in the range of $10,000 to $12,000.3' The price has been reduced somewhat since then, with a one-year supply of AZT falling to a price range of $4,000 to $6,000 and with the total sales of AZT increasing from $158 million to $540 million.32 AZT sells for one and a half dollars per dose even though the cost of production is estimated at forty cents per dose.33 Prices of HIV/AIDS drugs are not uniform across all markets. Pharmaceutical companies have segmented the global market for HIV/AIDS drugs into a number of sub-markets and have set different prices within these sub-markets. Pharmaceutical companies charge a great deal more for their drugs within the United States domestic market than they do within foreign markets.34 Glaxo-Welcome, the present holder of the AZT patent, has offered AZT to South Africa's public health service at 70% below the world average price.35