Obesity Drug Tests Upended by Placebo Patients Leaving Early (1)

The companies developing new weight-loss medicines have a problem: the balance of power has shifted, and patients are bailing out of their clinical trials.

People who don’t lose weight can quickly figure out that they were assigned to take a placebo instead of the real drug. And with highly effective obesity medications on the market — Eli Lilly & Co.’s Zepbound and Novo Nordisk A/S’s Wegovy shot and pill — that are getting cheaper, there’s little reason to stay in a study that doesn’t yield the intended benefits.

The new reality upends one fundamental assumption of clinical trials ...