The disposition of paclitaxel in humans is nonlinear. Paclitaxel metabolism to 6 alpha-hydroxylpaclitaxel is likely an important detoxification pathway. Myelosuppression is related to the duration that plasma paclitaxel concentrations are > or = 0.05 mumol/L. Trials of new doses and schedules of paclitaxel should take into account its nonlinear disposition to rule out adverse clinical consequences, especially if the drug is administered by short infusion. Our pharmacokinetic model should prove to be a powerful tool in predicting paclitaxel disposition, regardless of dose and schedule, and should facilitate further pharmacodynamic investigations.
PURPOSE To define the maximum-tolerated dose (MTD) and better tolerated sequence of paclitaxel by 3-hour infusion plus bolus doxorubicin (DOX) and to evaluate antitumor efficacy. PATIENTS AND METHODS Thirty-five women with metastatic breast cancer (dominant visceral metastases in 56%, and involvement of > or = three sites in 67%) who never received chemotherapy of any type were studied. Paclitaxel every 3 weeks (125 mg/m2 starting dose) was increased by 25-mg/m2 steps in subsequent cohorts of patients. DOX (60 mg/m2 fixed dose) was administered 15 minutes before the start of or after the end of paclitaxel for a maximum of eight cycles. Subsequently, patients in continuous response could receive single-agent paclitaxel (175 to 200 mg/m2 every 3 weeks). The drug sequence was alternated in consecutive patients and in the first two cycles. RESULTS Severe neutropenia that lasted greater than 7 days (n = 4), febrile neutropenia (n = 7) and grade III oral mucositis (n = 6) defined the MTD of paclitaxel at 200 mg/m2 in 34 assessable patients. Grade II peripheral neuropathy occurred in 33% of patients. Six women (18%) developed clinically reversible congestive heart failure (CHF) after a median of 480 mg/m2 total DOX. Drug sequence had no effect on toxicities. High efficacy on all metastatic sites in 32 assessable patients accounted for a 41% complete response (CR) rate (95% confidence interval [CI], 24% to 59%) and 94% overall-response rate (95% CI, 79% to 99%). After a median follow-up of 12 months (range 3 to 18), the median response duration is 8 months (range, 2+ to 18+) for complete responders and 11 months (range 1+ to 15+) for partial responders. CONCLUSION The rate of CR and incidence of CHF may be an expression of therapeutic and toxic enhancement due to the schedule used in this trial. Until clarification of this possibility, this promising combination should be used in investigational trials.
PTX, as clinically formulated in CEL, is responsible for a nonlinear disposition of DOX and DOL. Nonlinearity is PTX- and DOX-dependent, and possibly caused by competition for biliary excretion of taxanes and anthracyclines mediated by P-gp. Nonlinearity indicates that even minor modifications of dose and infusion duration of DOX and PTX may lead to unpredictable pharmacodynamic consequences. The postulated role of P-gp suggests that CEL is clinically active, and advises caution in designing combinations of PTX with other drugs that are substrate for P-gp.
In tumor-bearing mice, cyclic fasting or fasting-mimicking diets (FMD) enhance the activity of antineoplastic treatments by modulating systemic metabolism and boosting antitumor immunity. Here we conducted a clinical trial to investigate the safety and biological effects of cyclic, five-day FMD in combination with standard antitumor therapies. In 101 patients, the FMD was safe, feasible, and resulted in a consistent decrease of blood glucose and growth factor concentration, thus recapitulating metabolic changes that mediate fasting/FMD anticancer effects in preclinical experiments. Integrated transcriptomic and deep-phenotyping analyses revealed that FMD profoundly reshapes anticancer immunity by inducing the contraction of peripheral blood immunosuppressive myeloid and regulatory T-cell compartments, paralleled by enhanced intratumor Th1/cytotoxic responses and an enrichment of IFNγ and other immune signatures associated with better clinical outcomes in patients with cancer. Our findings lay the foundations for phase II/III clinical trials aimed at investigating FMD antitumor efficacy in combination with standard antineoplastic treatments.
Significance:
Cyclic FMD is well tolerated and causes remarkable systemic metabolic changes in patients with different tumor types and treated with concomitant antitumor therapies. In addition, the FMD reshapes systemic and intratumor immunity, finally activating several antitumor immune programs. Phase II/III clinical trials are needed to investigate FMD antitumor activity/efficacy.
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The higher than expected incidence of neutropenia and GI toxicity might be related to the prolonged half-life and accumulation of total and free Pt after daily administrations. Lack of nephrotoxicity and the low urinary excretion support the use of the drug without hydration. The single intermittent schedule has been selected for clinical development.
Different peripheral blood parameters have emerged as prognostic biomarkers in breast cancer (BC), but their predictive role in Human Epidermal growth factor Receptor 2 positive (HER2+) advanced BC (aBC) patients receiving dual anti-HER2 blockade remains unclear. We evaluated the impact of the Pan-Immune-Inflammatory Value (PIV), defined as the product of peripheral blood neutrophil, platelet, and monocyte counts divided by lymphocyte counts, on the prognosis of HER2+ aBC patients treated with first line trastuzumab-pertuzumab-based biochemotherapy. We also evaluated the association between the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), and the monocyte to lymphocyte ratio (MLR) and clinical outcomes. Cox regression models were used to estimate the impact of these variables, as well as of other clinically relevant covariates, on patient survival. We included 57 HER2+ aBC patients treated with taxane-trastuzumab-pertuzumab in our Institution. High baseline MLR, PLR, and PIV were similarly predictive of worse PFS at univariate analysis, but only high PIV was associated with a trend toward worse PFS at multivariable analysis. Regarding OS, both high PIV and MLR were associated with significantly worse patient survival at univariate analysis, but only the PIV was statistically significantly associated with worse overall survival at multivariable analysis (HR 7.96; 95% CI: 2.18–29.09). Our study reveals the PIV as a new and potent predictor of OS in HER2+ aBC patients treated with first line trastuzumab-pertuzumab-containing biochemotherapy. Prospective studies are needed to validate this new prognostic parameter in HER2+ aBC.
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