Novo Nordisk’s American depositary receipts tumbled almost 6% Friday after the drugmaker reported mixed results from a study of an experimental weight-loss pill. The pill, monlunabant, helped people lose weight in the mid-stage study, but Leerink Partners called the magnitude “underwhelming,” and analysts noted that some patients had anxiety and other neuropsychiatric side effects. Its stock-price decline underscores just how closely investors are following the industry race to develop a weight-loss pill that may be less expensive and easier to manufacture than injected drugs like Wegovy and Eli Lilly’s Zepbound.