New cancer drugs launched each year increased from 0.5 in the 1990s to over eight in 2022 among high-income countries, whereas they increased from 0.1 to 1.5 a year among upper-middle-income countries, according to a global analysis revealing "significant" and "widening" disparities.

New drug launches remained minimal in lower-middle-income and low-income countries, it found.

Published in the British Medical Journal (BMJ) Global Health, the analysis highlighted significant disparities in both availability and timeliness of these medicines worldwide, according to researchers.

The inequities could explain the poor cancer outcomes across many countries, especially the low- and middle-income ones, where mortality-to-incidence ratios have been studied to be higher, despite overall cases being lower, the researchers, including those from The Pennsylvania State University, US, said.

The measure 'mortality-to-incidence ratio' is used to compare inequities in cancer outcomes. It is calculated by dividing the deaths due to cancer by the case count in a given year.

The disparities are likely to worsen with low- and middle-income countries expected to bear the major brunt of the projected surge in global cancer cases in the years to come, the researchers added.

Over the study period, from 1990 to 2022, 568 new anti-cancer drugs were found to have been launched. The researchers included nearly 4,200 drug launches and regulatory approvals from across 111 countries in their analysis.

The data was taken from Pharmaprojects, a commercial database tracking global pharmaceutical research and development (R & D) activities in over 150 countries. Data from World Bank and Global Cancer Observatory was also used in the study.

Of the 568 new cancer drugs, the US saw the most launches at 345, followed by Japan and Canada at 224 and 221, respectively, the researchers found.

Over 190 of the new drugs were launched in the UK and 169 in China during 1990-2022.

Most of the new drugs were launched in the world's high-income regions such as North America, Western Europe, East Asia, and Australia, while the fewest were launched in low- and middle-income regions, including Africa and Southeast Asia, the researchers found.

Further, while over half of the new drugs became available in the past decade, 35 per cent of the 568 were available in only one country, 22 per cent in two to five countries and 43 per cent in over five countries, the team found.

"The average number of new cancer drug launches per country each year increased from 0.5 per year in the early 1990s to 8.7 per year in 2022 in high-income countries, from 0.1 to 1.5 per year in upper-middle-income countries, while remaining minimal among lower-middle-income and low-income countries," the authors wrote.

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