Global spending on cancer drugs reached $91 billion in 2013, and has been growing at an annual average of 5.4% over the last five years compared with around 14.2% a year during 2003-08, according to new research.

The recent lower growth rate reflects fewer breakthrough therapies for very large patient populations, as well as patent expiries, reductions in the use of supportive-care medicines and stronger payer management, says the study, from the IMS Institute for Healthcare Informatics.

However, targeted therapies have dramatically increased their share of global oncology sales, from 11% a decade ago to 46% last year. And while payers have intensified their scrutiny of these medicines’ value relative to their incremental benefits over existing treatments, the average cost per month for a branded oncology drug in the US is now around $10,000, up from an average of $5,000 a decade ago.

Concentrated or single-payer health systems, and those utilising health technology assessment (HTA) processes, tend to pay less than US prices for medicines – the pricing discount mechanisms used in major European markets typically drive net prices down by some 20%-40% compared with US list prices, the study finds.

While biologic drugs now represent under half of the oncology market, the impact of non-original biologics (those based on an original molecule not introduced by its manufacturer in a particular market) and of biosimilars is growing. The introduction of regulatory pathways for biosimilars and increased production capacity around the world are driving a new competitive dynamic in the $40 billion-plus biologics portion of the oncology market, says IMS. 

However, it forecasts the potential role of biosimilars in developed countries to be limited by the expected flow of patent-protected innovations that will displace older, off-patent products subject to biosimilar competition. These agents already play a role in the supportive-care segment of European oncology market, and are likely to do the same in the US in the near term.

And in low- and middle-income countries, non-original biologics will play a significant role in oncology; they already account for 60% or more of certain recombinant and synthesised biologics, the study says.

It also forecasts that, globally, biosimilars should generate $6-$12 billion in oncology sales by 2020, increasing the level of competition but accounting for less than 5% of the total biologics market by that time.

- IMS says its $91 billion figure for 2013’s market is measured at ex-manufacturer prices and does not reflect off-invoice discounts and rebates.