The original Retain was licensed from ALRI so naturally a newer version had to come out when the license expired.
The original contained tyramine, b-triol, and clary sage.
Retain2 contained 7-oxo, b-triol, and Relora.
As GITRDONE, mentioned, the original was designed for use in PCT as cortisol control. After the license was over, new research came out on things to lower cortisol with (i.e. relora), and such were used to make the new Retain2.