Cost-benefit analyses are crucial to inform treatment policies, particularly when the cost of patented drugs is very high. The cost of patented drugs is the limiting factor in hepatitis C treatment. However, hepatitis C drug costs are expected to fall following patent expiration, due to generic drug introduction.

An existing mathematical model by Shih et al was extended to consider lower-cost future generics in health economic models of hepatitis C. The model compared the cost-effectiveness of treating patients now with patented drugs vs postponing treatment until after patent expiration.

For ledipasvir-sofosbuvir, this study finds that it is almost always more cost effective to treat hepatitis C with high-cost patented drugs immediately rather than waiting for patent expiry. For ledipasvir-sofosbuvir, a generic would need to enter the market at <16.40% of the patented price for delayed treatment to be cost effective. The further that patent expiry is in the future, the more cost effective delayed treatment becomes; however, uncertainty about generic pricing and market entry times are also higher if patent expiry is in the distant future.

It is more cost effective to treat hepatitis C sooner rather than later, regardless of the stage of the disease, and despite the high cost of patented drugs. However, patented drugs are being produced globally for prices much lower than those seen in the UK. Therefore, negotiation of patented drug prices with pharmaceutical companies may be a crucial step in cost effective treatment of hepatitis C.