High-dose folinic acid (FA) and fluorouracil (FU) plus or minus thymostimulin (TS) for treatment of metastatic colorectal cancer: results of a randomized multicenter clinical trial.

The purpose of this study was to ascertain the possible protective effect of thymostimulin (TS) on chemotherapy-induced leukopenia and related febrile episodes, beside the potential of improving therapeutic efficacy and tolerability of high-dose folinic acid (FA) plus fluorouracil (FU) in metastatic colorectal cancer. In 211 evaluable patients the objective responses were 19/105 (18%) in the FA-FU arm versus 32/106 (30%) obtained with the same regimen plus TS. The difference was statistically significant (p = 0.