Science and medicine are getting very close to big and meaningful breakthroughs on diseases and maladies that were once only somewhat treatable with very expensive routines of medications. Gene therapy breakthroughs have been a big part of this, with the FDA approving promising gene therapy trials, and even more exciting results coming in from around the world.

But, it is interesting to see information about how some of the health care industry thinks about all this. How they think can be a predictor on what they will eventually do.

In an April 10 report for biotech clients, Goldman Sachs delved into a pretty awkward subject – cures. Analysts noted that one-shot cures for diseases are not great for business as they’re bad for longterm profits.

The investment banks’ report, titled “The Genome Revolution,” asks clients: “Is curing patients a sustainable business model?” The answer may be “no,” according to follow-up information.

Analyst Salveen Richter and colleagues laid it out: “The potential to deliver ‘one shot cures’ is one of the most attractive aspects of gene therapy, genetically engineered cell therapy, and gene editing.

However, such treatments offer a very different outlook with regard to recurring revenue versus chronic therapies… While this proposition carries tremendous value for patients and society, it could represent a challenge for genome medicine developers looking for sustained cash flow.”

They pointed to Gilead Sciences, which markets treatments for hepatitis C that have cure rates exceeding 90 percent.

In 2015, the company’s hepatitis C treatment sales peaked at $12.5 billion.

But as more people were cured and there were fewer infected individuals to spread the disease, sales began to languish. Goldman Sachs analysts estimate that the treatments will bring in less than $4 billion this year.

Gilead’s rapid rise and fall of its hepatitis C franchise highlights one of the dynamics of an effective drug that permanently cures a disease, resulting in a gradual exhaustion of the prevalent pool of patients,” the analysts wrote.

The report noted that diseases such as common cancers — where the “incident pool remains stable” — are less risky for business.