This means that 320 million people - 40% of Europe's population - who could benefit from treatment with disease modifying drugs (DMARDs) would struggle to get access to them, say the researchers.
DMARDs are extremely effective for the treatment of rheumatoid arthritis, and the European League Against Rheumatism (EULAR) recommends the use of synthetic DMARDs immediately after diagnosis to halt progress of the disease. But they are expensive.
The authors therefore surveyed key experts in 49 countries during 2011 about the availability, affordability and acceptability of both synthetic DMARDs, such as methotrexate and leflunomide, and biological DMARDs, such as infliximab and etanercept.
In all, 46 countries took part in the survey, which included those in Eastern Europe, Scandinavia, and Western Europe, as well as Turkey and Uzbekistan.
The responses revealed wide disparities in access to DMARDs. Six countries did not reimburse use of any of the five synthetic DMARDs included in the survey, and 10 countries did not pay for any biological DMARDs.
The cost of one year's treatment with a synthetic DMARD did not exceed any country's per capita GDP). But the cost of one year's treatment with a biological DMARD was higher than the per capita GDP of 26 countries, by as much as 11 times, the findings indicated.
That means that almost 40% of the population of Europe - equivalent to 320 million people - would have severely restricted access to biological DMARDs, say the authors.
Access was especially poor in countries in Central and Eastern Europe and those least well off, economically and socially, the findings showed.
The number of days a person on an average income would need to work to pay fhe full drug price of 30 days' treatment with a biological DMARD ranged from 12 days in Luxembourg to 190 in Romania.
Although it's not possible to draw definitive conclusions on the impact on health of restricted access, higher drugs prices were associated with increased disease activity and poorer physical functioning.
"Assuming needs for treatment with DMARDs are similar across countries, differences in access to medical treatment are unfair and raise alarming issues of inequity," write the authors.
Wealthy Western countries continually debate the budgetary impact of expensive drugs, but unaffordability in low income countries is rarely discussed, they note.
The cheap cost of labour means that these expensive drugs are rarely going to be considered a return on investment, in terms of improved productivity, they add, and drug pricing in Europe should be revised, say the authors.