Folinic acid does improve 5-fluorouracil activity in vivo. Results of a phase III study comparing 5-fluorouracil to 5-fluorouracil and folinic acid in advanced colon cancer patients.

We report the results of a phase III trial in which we compared 5-fluorouracil (5-FU) to 5-FU and folinic acid (FA) in 150 previously untreated metastatic colon cancer patients. Patients were randomized in the ratio of 1:2 to receive 5-FU (370 mg/m2, i.v., for 5 days) in arm A or equidose 5-FU plus FA (200 mg/m2, i.v., for 5 days) for arm B, each cycle being repeated every 4 weeks. Five of 49 evaluable arm A patients (10.2%) and 31 of 97 arm B (31.9%) achieved a complete or partial response (p < or = 0.01). Median survival time of arm A patients was 6 months (mean: 6.18), while it was 8 months (mean: 9.01) for arm B cases (p < or = 0.05). In conclusion, our data indicate that FA can enhance 5-FU activity and that this combination is an effective palliative treatment for metastatic colon cancer patients.