In March, the Food and Drug Administration issued a complete response letter -- the agency's euphemism for a rejection letter -- to Sanofi (NASDAQ: SNY) and Lexicon Pharmaceuticals (NASDAQ: LXRX) for their application to approve Zynquista as a treatment for type 1 diabetes.
A few months later, AstraZeneca got the same notice for using Farxiga as a treatment for type 1 diabetes.
Zynquista and Farxiga are both sodium-glucose cotransporter (SGLT) inhibitors. As the name implies, SGLT proteins -- there are two main ones, SGLT-1 and SGLT-2 -- transport sodium and glucose (sugar) from the kidneys back into the bloodstream. By inhibiting the proteins, more sugar ends up being excreted in the patient's urine instead of causing damage circulating through the bloodstream.