An economist says government buyers need more transparency.

(Bloomberg) — Even among countries with curbs on drug prices, the costs of cancer treatments vary widely, researchers wrote in the Lancet Oncology journal.

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New Zealanders pay almost five times what Australians do for Eli Lilly & Co.’s Gemzar, used to treat breast, lung, pancreatic and ovarian cancers, according to the study of publicly available pricing information from 18 countries. In Germany, Merck & Co.’s Intron A for skin and blood cancers costs triple what it does in Greece, the researchers found.

That variation is likely to continue as some countries cut their own confidential deals with drugmakers. Australia, the United Kingdom, the Netherlands and Italy have gotten discounts on cancer medicines through such agreements. Those discounts aren’t disclosed, so countries that set reimbursements based on what their neighbors pay — a practice called price referencing — may be missing out, the researchers said.

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“Although these agreements ensure patient access to new drugs, other countries risk overpaying when setting drug pricing,” said Sabine Vogler, the economist who oversaw the study and leads the World Health Organization’s Collaborating Centre for Pharmaceutical Pricing and Reimbursement Policies in Vienna. “There needs to be far more transparency.”

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The researchers looked at information for 31 cancer drugs in 16 European countries, Australia and New Zealand as of June 2013. Data on what countries actually pay for medicines is scarce, they said.

The study found:

  • Gemzar, also known as gemcitabine, cost 209 euros ($228) per vial in New Zealand and 43 euros in Australia.
  • In general, Sweden, Switzerland and Germany pay the most for the cancer treatments in the study, while the U.K., Spain, Portugal and Greece pay the least.

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