From the article, which cites CGD's procurement work:
"Across low- and middle-income countries, the prices of essential medicines, such as cancer treatments, HIV antiretrovirals, and antibiotics, display substantial variations, with the locally observed prices sometimes being many times higher than the lowest international reference level for generic equivalents. Chalkidou et al. (2020) show that some purchasers in low- and middle-income countries pay up to 30 times the minimum international reference price for basic generic medicines, such as paracetamol, insulin, and omeprazole. High prices, in turn, deplete already-limited public health budgets and generate shortfalls in access, especially for the poorest and neediest members of society."
"Existing economic research has addressed the issue of affordable access to drugs in developing countries mostly from a patent protection angle. Several authors have analysed the trade-off between the potential costs of restrictive patent policies (due to the higher prices resulting from monopolistic pricing policies) and the potential benefits related to the faster diffusion of new drugs to markets enjoying stronger patent protection (Chaudhuri et al. 2006, Kyle and Qian 2014, Cockburn et al. 2016)."