Eli Lilly stock can be a smart addition to a diversified long-term investment portfolio.Eli Lilly (LLY 1.78%) recently announced stellar results from a phase 3 clinical trial, Triumph-4, which evaluated efficacy and safety for the two highest doses of its next-generation anti-obesity candidate, retatrutide.The trial showed that a 12 mg weekly injection of retatrutide (the highest evaluated dose) delivered an average of 28.7% reduction in body weight over 68 weeks, along with a decrease in pain from knee art ...