FGF21 and metabolic disease: Based on the longer half-life of FGF21 compared to FGF19, and the metabolic effects of FGF21, FGF21 and more stable analogs have gained attention of several pharmaceutical and biotechnological companies like Lilly Research Laboratories (LY2405319), Pfizer (PF05231023), and Bristol-Myers Squibb [(PEG-)cFGF-21] to interfere in metabolic diseases.