A Better FIT! Use of Medication to Improve Weight Loss in Suboptimal Early Responders to Behavioral Treatment

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Study Overview

A 28-week research study is being conducted that is designed to help all participants lose weight. All participants will receive lifestyle modification (diet, exercise, and behavioral treatment). Participants who do not lose weight with lifestyle modification alone also will be prescribed an FDA-approved weight loss medication (phentermine) or placebo. This study requires at total of 4 in-person screening and assessment visits at the University of Pennsylvania during the 7-month study. All lifestyle counseling visits are conducted remotely via telehealth.

Study Description

All participants will receive the same lifestyle modification program of diet, physical activity, and behavior therapy, which is currently recommended as the first-line treatment for weight loss. After completing 4 weeks of this treatment, they will attend a progress assessment visit in which they will review their weight loss with the research team. 

Most participants (2 out of 3) are expected to successfully lose weight with lifestyle modification alone. Because early weight loss predicts later success, individuals whose weight loss is on target are not likely to need additional tools to help them to succeed. These individuals will continue to receive an additional 24 weeks of lifestyle modification to help them to achieve their goals. 

For the minority of participants who lose minimal weight with lifestyle modification, we will evaluate whether adding the weight loss medication phentermine helps them to achieve greater weight loss, as compared with being prescribed placebo. To do this, participants with slow early weight loss after 4 weeks of treatment will be randomly assigned to either phentermine or placebo in addition to continued participation in the lifestyle modification program for 24 more weeks. 

To see if you may be eligible for this study, please complete the prescreening questions below. You may be asked some personal health questions. You do not have to answer any questions you do not wish to answer, and you may stop at any time. Answering these questions is voluntary. This means that, no matter what you decide to do, your decision will not affect your relationship with or care provided by the University of Pennsylvania. 
The screening questions below do not send any information directly to the research team.  None of your answers will be saved by the research team. If you appear to meet criteria, you can choose to notify the research team of your interest in the study through the iConnect system or by phone. 

  • Study Identifier: 832077

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