Influence of proton pump inhibitors and H2-receptor antagonists on the efficacy and safety of dasatinib in chronic myeloid leukemia patients.

We evaluated the effect of proton pump inhibitors (PPIs) and H2-receptor antagonists (H2RAs) on the efficacy and safety of dasatinib for chronic-phase chronic myeloid leukemia (CP-CML). Retrospective analyses were performed for patients with CP-CML who received dasatinib at seven hospitals between April 2009 and December 2016. Seventy-three patients were identified, 16 of whom received PPIs or H2RAs concurrently with dasatinib. Major molecular response at 12 months was observed in 13 of 13 patients (100%) with concurrent PPIs or H2RAs (combination group), and in 23 of 51 patients (45.1%) who received only dasatinib (dasatinib-alone group; P < 0.001). Deep molecular response at 12 months was observed in four of six patients (66.7%) in the combination group, and seven of 38 patients (18.4%) in the dasatinib-alone group (P = 0.027). Dasatinib chemotherapy was stopped after 18 months for 25 patients (43.9%) from the dasatinib-alone group, but for none from the combination group. Combination treatment with PPIs or H2RAs did not reduce the efficacy of dasatinib. PPIs and H2RAs reduce the incidence of dasatinib discontinuation due to adverse events and increase the efficacy of dasatinib chemotherapy for patients.

Elevations of urinary pH may lower vancomycin serum concentration.

OBJECTIVE: This study investigated endogenous factors that may increase the elimination of vancomycin (VCM) in adult methicillin-resistant Staphylococcus aureus (MRSA) patients with pneumonia. METHODS: 48 patients (32 men and 16 women) admitted to the National Hospital Organization Kumamoto Medical Center for pneumonia due to MRSA were evaluated. VCM (500 - 2,000 mg/dose) was administered intravenously for 60 - 120 min at 8- - 12-h intervals. The dose of VCM prescribed was determined based on the treatment guidelines of the Infectious Diseases Society of America and was dependent on a patient's creatinine clearance. RESULTS: Univariate analysis identified that potassium value (K) (p = 0.081) and urinary pH (p = 0.026) were possibly associated with decreased VCM concentration. Multivariate analysis confirmed that urinary pH was an independent risk factor for VCM clearance (p = 0.029). VCM clearance in patients with a urine pH of 8 was significantly higher (p = 0.032) than in patients with a urinary pH of 5. As urinary pH increased in alkalinity, a greater decrease in VCM concentrations was observed. CONCLUSIONS: Elevation of urinary pH promotes the urinary excretion of VCM, likely by promoting the dissociation of the carboxyl group of VCM. Thus, in the clinical setting, urinary pH should be measured and considered when determining dosage, as it may affect the VCM blood concentration.