The certainly were tried. One of Diocletian's famous measures to counter inflation, the Edict on Maximum Prices, caused at least in part by pretty severe currency debasement, was price controls.

Unfortunately, he continued to debase the coinage. Price controls generally are hard to enforce even in modern times, and most economists would likely tell you they are only going to be effective in relatively closed markets for relatively short times of crisis. What survives of the edict suggests that they knew somewhat that inflation was related to the coinage debasement, but clearly not enough to stop it (or enough to make the sacrifices required to do so). In addition, the edict set the price of a huge number of goods, including luxury items. Prior to this, there were certainly other attempts to set prices, either through government subsidy/distribution, or other price controls, however they were attempts to fix the market in stone, and that is difficult even with modern understandings.

Here's a decent link with a short summary of Roman attempts to deal with inflation: http://mises.org/library/price-fixing-ancient-rome

In 301 The Emperor Diocletian enacted price controls in his attempt to stabilize the Empires economy. The results were what we would now expect. Even with the penalty of death a possibility, people still largely ignored them. This is a link to the actual Edict translated from the Latin. Its ponderous as most legal writings are, but you may find it interesting.http://orion.it.luc.edu/~jlong1/priceed.htm