Abstract
BACKGROUND: The use of meal replacement products (MRPs) to obtain a caloric deficit while maintaining micro- and macronutrient requirements, has a long tradition in obesity medicine. Limitations include low compliance, variability in efficacy, adverse events (related to acute changes in nutrient intake), and risk of weight regain when discontinued, and their popularity has declined after the emergence of potent GLP-1 receptor analogues (GLP1-RAs). However, GLP-1RAs have limitations, including dose-dependent risk for adverse events (AEs), high cost, as well as weight regain when discontinued. Although concomitant use of MRPs and GLP-1RAs could address some of the limitations, there is a scarcity of data reported on this. Herein we report real world clinical experience of such combined use. METHODS: This retrospective case evaluation involved people with obesity that concomitantly used MRPs (Optifast) and a GLP-1RA and were followed at one of three weight management centers in Australia or South Africa. Parameters collected were gender, age, co-morbidities, height, weight, frequency/amount of MRPs used, dose/type of GLP-1RA used, duration of combined use, and occurrence of AEs. Written informed consent for use of data was obtained from each individual, and the data were managed in an anonymized form and summarized descriptively. RESULT: A total of seven (5 females) individuals (mean [min, max] age 49 [30,66] years, BMI 44.8 [30.7, 57.9] kg/m(2)) initiated either semaglutide (n=4) or liraglutide (n=3) concomitantly with daily MRPs (starting number of servings/day 2.7 [1,6]) for a duration of 12 [4, 25] months. Change in weight/BMI/% TBW was -32.0 (-9.6, -77.8) kg/-10.3 (-3.4, -24.5) kg/m(2)/-24.2 %. Five individuals experienced ≥1 GLP-1RA related AE (nausea, reflux, burping, diarrhea, constipation). One individual discontinued GLP-1RA, whereas two persons discontinued the use of MRPs. CONCLUSIONS: MRPs can be initiated concomitantly with a GLP-1 RA for weight management. This might enhance weight-loss effectiveness, with potential additional benefits that should be elucidated in further and larger studies.