Viking Therapeutics' highly anticipated weight-loss pill topped Wall Street's expectations — and a rival pill from Novo Nordisk — after just four weeks of treatment. Patients who took the highest dose of Viking's pill, 100 milligrams, lost 8.2% of their body weight. The 6.8% difference is far better than investors' expectations the obesity pill to outperform the placebo by 5% to 6%, William Blair analyst Andy Hsieh said.