There is research on this, however the research has been done on another form of Carnitine, called L-Carnitine-L-Tartrate
In a new study, more than 900 adults with obesity and diabetes took the drug for a year and five months, and those on the highest dose lost an average of 34 pounds, or nearly 16% of their starting weight
5.7 Hypersensitivity Reactions There have been postmarketing reports of serious hypersensitivity reactions in patients treated with sitagliptin, one of the components of JANUMET
Similar to other peptide-bound GLP-1R structures 13,16 , exendin-4 and oxyntomodulin adopted a continuous alpha helix, with their C-terminus bound within the ECD and their N-terminus bound deep within the TMD forming extensive interactions with residues within TM1, TM2, TM3 TM5, TM6, TM7 and ECL2 (Figs