Metreleptin is a once daily subcutaneously administered leptin analogue approved by the FDA in 2014 for use in people with leptin deficiency or congenital/acquired lipodystrophy, with good clinical results in these conditions [86]
If you want to train well enough to keep muscle, your nutrition has to help you do that
NSL literature pointer PMID 26863380 L-Carnitine laboratory index [PMID: 26863380] National Science Labs indexing note for PMID 26863380: review the PubMed methods, models, and limitations before citing
Either way, they're support, not a substitute
Though with similar effects as some pre-existing drugs (semaglutide, liraglutide, exenatide, etc.) targeting diabetes and obesity, tirzepatide is considered a first-in-class medication for demonstrating action on both the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors