US-based Center for Global Development (CDG) says that lower to middle-income countries are losing out when purchasing what it calls branded generic drugs.

Report author Amanda Glassman told BBC Newsday that one of the problems is that many countries are buying these branded drugs when it would be cheaper to acquire what she described as "unbranded quality-assured drugs" - guaranteed medicines which do not have a internationally recognised drug company name associated with them.

She also said that many countries do not have a coordinated drugs purchasing policy meaning that they are unable to negotiate a lower price.

The kinds of medicines affected range from basic pain killers, to statins to treat blood pressure and herceptin for breast cancer treatment.

The CDG says affordable drugs are necessary and in their absence "lasting health gains will remain elusive".