In this study, researchers are comparing two medicines to help people with advanced cancer who are losing their appetite. The medicines are olanzapine and megestrol acetate. Olanzapine is usually used to treat mental health issues, but it might also help with appetite. Megestrol acetate is currently a common treatment for appetite loss in cancer patients.

Researchers want to see if olanzapine is better than megestrol acetate at improving appetite and helping patients gain weight. Patients will be randomly assigned to take either olanzapine or megestrol acetate once a day for up to 4 weeks. To join, you must be at least 18 years old, have advanced cancer, and be experiencing appetite or weight loss. You also need to be able to take medications by mouth and speak English or Spanish.

• The study lasts for up to 4 weeks with daily medication.
• Participants must use birth control due to potential risks to unborn babies.
• No compensation is mentioned, but participation may help improve appetite treatment.