<a href="http:&#x2F;&#x2F;theconversation.com&#x2F;explainer-evergreening-and-how-big-pharma-keeps-drug-prices-high-33623" rel="nofollow">http:&#x2F;&#x2F;theconversation.com&#x2F;explainer-evergreening-and-how-bi...</a><p>I&#x27;m not an expert and I can&#x27;t comment on specifics. But I&#x27;m of the opinion that a small enhancement is not the same as an invention of a drug and it doesn&#x27;t come anywhere close to extending the life of the patent - <i>unless</i> that tiny change actually makes a big different in effectiveness.<p>Any good patent system should find a good balance between the two seemingly conflicting goals of incentivizing companies to innovate and keeping the price down for patients.