International price comparisons of Alzheimer's drugs: a way to close the affordability gap

Background: Alzheimer's drugs are believed to have limited availability and to be unaffordable in low- and middle-income countries compared to high-income countries. The price, availability and affordability of Alzheimer's drugs have not been reported before. Methods: During 2007 an international survey was conducted in 21 countries in six continents (Argentina, Australia, Brazil, the Dominican Republic, France, India, Japan, Macedonia, Mexico, New Zealand, Nigeria, the Philippines, Portugal, Serbia, South Korea, Switzerland, Taiwan, Thailand, Uganda, the U.K. and the U.S.A.). Prices of Alzheimer's drugs were compared using the affordability index (the total number of units purchasable with one's daily income) derived from purchasing power parity (PPP) converted prices as well as raw prices. Results: Donepezil is available in all 21 countries, whereas the newer drugs are less available. A 5 mg tablet of branded originator donepezil costs just US$0.26 in India and US$0.31 in Mexico, whereas it costs US$6.64 in the U.S.A. Pricing conditions of rivastigmine, galantamine and memantine appear to be similar to that of donepezil. The cheapest branded originators are from India and Mexico. However, in terms of PPP, Alzheimer's drugs in other low- and middle-income countries are much more expensive than in high-income countries. Most people in low- and middle-income countries cannot afford Alzheimer's drugs. Conclusions: Alzheimer's drugs, albeit available, are often unaffordable for those who need them most. It is hoped that equitable differential pricing will be applied to Alzheimer's drugs.