Fifty-six patients are randomized to one of four treatment arms, as follows: high-dose megestrol acetate alone; dronabinol alone; high-dose megestrol acetate combined with dronabinol; or low-dose megestrol acetate combined with dronabinol. Treatment continues for 12 weeks. Patients are evaluated for toxicity, preliminary evidence of response (e.g., weight gain), and steady-state pharmacokinetics of drug therapies.