GLP-1 weight-loss medication bottle and capsules on a desk with glasses and notebook, illustrating the expanding obesity drug market. Key Points Three companies to watch in the fast-growing GLP-1 space include firms with market capitalizations ranging from about $4 billion to nearly $1 trillion. Eli Lilly's size and dominant position allow it to develop multiple GLP-1 medicines and to expand rapidly into many corners of the world. Viking Therapeutics and Structure Therapeutics are much smaller, but eac ...