US Drug Pricing Order Is Upending Health Care in Switzerland

For the past few years, Swiss oncologist Christoph Renner has treated blood cancer patients with Lunsumio, a new drug that helps the immune system recognize and destroy malignant cells. Then, last summer, Renner got an email from Roche Holding AG, Lunsumio’s manufacturer, informing him the treatment would no longer be available in Switzerland because health insurers there wouldn’t pay for the infusions. “You see what’s possible,” says Renner, a professor at the University of Basel, “and then you’re told you can’t use it.”

The move was a response to rules President Donald Trump introduced that force drugmakers to reduce ...