You clearly don't work in medicine, healthcare, the pharma industry, or even understand how drugs work. I also suspect that you've had very basic instruction in biology. I get tired of hearing "pharma companies only make drugs that address symptoms so they can keep selling you drugs." I think you are conflating "disease treatment" and "cure". Most drugs are disease treatments, since permanent cures are not possible (at this time) for the vast majority of diseases. But, e.g., there were recent market approvals of 3 actual cures for hepatitis C.
Drugs are developed to have a mechanism of action that directly addresses underlying disease. When it costs in excess of $1 billion and 10 years to bring a drug to market, you don't waste time on something that you have no idea how it works. Never mind that FDA and every other health regulatory agency in the world frowns upon pharma companies saying "we have no idea how it works, but it does, so just approve it." You make sure you are targeting the molecular and cellular causes of the disease. The drugs drastically reduce the severity of the disease. This manifests in a reduction in symptoms. The average person sees it as "the drugs only treat symptoms, I still have the disease", but what is actually happening is the drug is treating the disease and reducing its severity and a reduction or disappearance of symptoms is really just a side effect of treating the disease.
TL;DR: "Treatment" and "cure" are not the same, and "cure" is often not possible at this time. So should pharma companies not bother?