A 2013 study found that ‘diseases of relevance to high-income countries were investigated in clinical trials seven to eight times more often than were diseases whose burden lies mainly in low-income and middle-income countries.’ The NEJM reported in 2009 that pharmaceutical companies were conducting more clinical trials in developing countries, yet ‘among the ongoing phase 3 clinical trials that we examined that were sponsored by US-based companies in developing countries, none were trials of diseases such as tuberculosis that disproportionately affect the populations of these countries.’ Of more than 1500 new drugs produced between 1975 and 2004, only 21 targeted malaria, tuberculosis and other neglected diseases that are most common in low-income countries.