Generics markets are gearing up for the expiry of patents on some of the first targeted cancer drugs. Its good news for greater access, but patients want reassurance that switching to generics wont put them at risk.
by Marc Beishon
Generic drugs are a huge and complex part of the healthcare market. Each year, dozens more become available as the patents that protect exclusive marketing rights for the originator drugs expire or are circumvented, and as developing countries gear up their pharmaceutical sectors.
Cancer drugs are no exception. According to recent figures, in a total global oncology drugs market approaching $100 billion, revenues from generics are growing at twice the rate of the market as a whole, and will reach more than $20 billion by 2018. The vast majority of all drug prescriptions are already for generics – more than 80% in the US, for example.
The market is complex for several reasons. One is that rules for marketing exclusivity for medicines, e.g. for orphan drugs (for rare diseases), vary across countries, giving rise to a patchwork of opportunities for generics. Indeed in India there has been a direct challenge to drug patents, the notable case being for imatinib (Glivec). Then there is the economics of producing generics. With prices for some reduced to just a few cents a dose, incentives to remain in production can disappear, which is one of the contributors to well-publicised shortages of cancer drugs in recent years.
And there are concerns about the quality of generic drugs. While most of the small-molecule cancer agents are straightforward to produce, they may be produced in facilities that differ from those of the originator company in levels of quality control and also in the amount of active and other substances used to make up a pill or an injectable dose.
A clear distinction can be made between small-molecule drugs, such as tyrosine kinase inhibitors (TKIs) like imatinib and chemotherapies like cisplatin on the one hand, and large-molecule ‘biologics’, such as monoclonal antibodies, on the other. The latter cannot be copied in the same way as small-molecule agents, and are part of a growing interest and market in ‘biosimilars’, which have more demanding regulatory requirements.
Full article here:
http://www.cancerworld.org/pdf/7816_pagina_28_34_Systems_Services_final.pdf