The role of vitamin B6 in the prevention of haematological toxic effects of linezolid in patients with cancer.

BACKGROUND: Linezolid is the first approved synthetic oxazolidinone with activity against multidrug-resistant gram-positive pathogens. However, haematological toxic effects of linezolid frequently limit its prolonged use, especially in patients with poor marrow reserves such as those with cancer receiving chemotherapy. Previous authors have reported that administration of vitamin B6 with linezolid reversed pancytopenia in two patients. METHODS: This is an open-label study of 31 patients with cancer who received linezolid at 600 mg twice daily and vitamin B6 at 50 mg/day for at least 2 weeks mean therapy duration and they were matched to 62 control patients who received linezolid without vitamin B6 to determine whether the concomitant use of vitamin B6 attenuates the haematological toxicity of linezolid in patients with cancer. RESULTS: Patients were matched according to age, underlying disease, duration of therapy, creatinine level and use of chemotherapy. We found no significant differences in the rate of haematological toxic effects between the two patient groups. The rate of thrombocytopenia was 13% in the vitamin B6 group and 15% in the control group (P = 0.82). Also, the rate of leucopenia was 7% versus 5%, respectively (P = 0.75). None of the patients in the vitamin B6 group had anaemia compared with 5% in the control group. CONCLUSIONS: Vitamin B6 given at 50 mg/day may have an impact on anaemia but did not prevent linezolid-induced thrombocytopenia or leucopenia in cancer patients.