Shares of Rigel Pharmaceuticals (RIGL) have gained 53.5% over the past four weeks to close the last trading session at $22.74, but there could still be a solid upside left in the stock if short-term price targets of Wall Street analysts are any indication. Going by the price targets, the mean estimate of $29.17 indicates a potential upside of 28.3%.The mean estimate comprises six short-term price targets with a standard deviation of $18.89. While the lowest estimate of $14 indicates a 38.4% decline from the ...