Italian to English Medical Medical: Pharmaceuticals

No context here. It's just from a list of pharmaceutical ingredients. Solfato sodico (or sulfato sodico) is obviously sodium sulfate, but I can't quite figure out where the T3 fits in. I get quite a few hits for T3 sulfate and even more for T3 sodium. Only one hit (from a Korean patent) for "T3 sodium sulfate", two questionable hits for "T3 sodium sulphate", none for "T3 sulphate sodium" six somewhat better hits for "T3 sulfate sodium", etc. Is this substance really that rare?

One of the articles from the search makes reference to "the thyroid hormone analogue O-[3-iodo-4-(sulfooxy)phenyl]-3,5-diiodo-l-tyrosine sodium salt (T3-sulfate, 1)" which gives us a clue as to what the T3 stands for, but the final solution remains out of my grasp. Any biochemists or pharmacists out there?