MannKind (NASDAQ:56400P706) is developing a revolutionary new insulin called Afrezza, which could compete directly with Novo Nordisk's (NYSE:NVO) NovaLog and Eli Lilly's (NYSE:LLY) Humalog. Afrezza is inhalable and rapid-acting, which could change the way diabetes is treated.

The market opportunity for diabetes care is massive, but there are a few things investors should know about MannKind before moving forward. Motley Fool Rule Breakers analyst Simon Erickson and analyst Max Macaluso look at some of the challenges that face MannKind, as well as keys for the company to succeed.