A randomized phase II and pharmacokinetic study of dacarbazine in patients with recurrent glioma

Chemotherapy regimen for recurrent uterine leiomyosarcoma

INTRODUCTION

Uterine leiomyosarcoma is a rare gynecological malignancy, the limited literature indicated that doxorubicin alone or gemcitabine/docetaxel combination is the preferred chemotherapy regimen. Given the rarity of the disease and the lack of high-level clinical evidence, there is no consensus on the best treatment.

CASE REPORT

We report a case of a patient with uterine leiomyosarcoma who recurred after adjustment treatment with doxorubicin, gemcitabine, docetaxel, and anlotinib; and required a new chemotherapy regimen.

MANAGEMENT AND OUTCOMES

The follow-up chemotherapy regimen was doxorubicin-liposome 40 mg/m2 on one day in combination with dacarbazine 250 mg/m2 on one to five days of intravenous infusion every 21 days. We monitored adverse effects during chemotherapy and the process was smooth.

DISCUSSION

It is important to comprehensively consider the patient's condition, and fully consider the efficacy, dosage, and adverse reactions of the chemotherapy regimen to determine the appropriate plan, in order to achieve the best therapeutic benefits for patients.

Quantifying plasma dacarbazine levels in advanced melanoma patients: a liquid chromatography-tandem mass spectrometry performance analysis

The aim of this study was to develop a robust liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying dacarbazine levels in the plasma of advanced melanoma patients, followed by an assessment of its analytical capabilities. The research encompassed the design of a high-performance liquid chromatography (HPLC) system, with the quantitative analysis performed using the multiple reaction monitoring (MRM) techniques and specific ion transition: 181.0 > 152.5 for dacarbazine and 187.1 > 158.6 for the internal standard (IS), dacarbazine-D6. The validation of the method involved an evaluation of parameters including linearity, detection limit, precision, and accuracy. Notably, the linear range extended from 10 to 1,000 µg/L for dacarbazine, and the method exhibited a detection limit of 10 µg/L. The method's precision, indicated by within-run and between-run coefficients of variation (CV), both being ≤4.2% and ≤8.3%, respectively. Furthermore, the accuracy of measurements, ranging from 86.1% to 99.4%, underscored the method's reliability. In clinical application, the dacarbazine levels of healthy control (n = 20) were 0.6 ± 0.02 μg/L; 770.9 ± 203.2 μg/mL in early-stage-melanoma patients (n = 22), and 588.7 ± 153.2 μg/mL in advanced melanoma patients (n = 25). The results serve as clinical evidence showing that long-term dacarbazine treatment affects the metabolism of dacarbazine.

Dacarbazine

Dacarbazine is a cell cycle nonspecific antineoplastic alkylating agent used in the treatment of metastatic malignant melanoma. This chapter contains the descriptions of the drug: nomenclature, formulae, chemical structure, elemental composition, and appearance. The uses and applications of dacarbazine and the methods that were used for its preparation are reported. The methods which were used for the physical characterization of the drug are ionization constant, solubility, X-ray powder diffraction pattern, crystal structure, melting point, and differential scanning calorimetry. The profile contains the spectra of the drug: ultraviolet spectrum, vibrational spectrum, nuclear magnetic resonance spectra, and mass spectrum. The compendial methods of analysis for dacarbazine include the United States Pharmacopeia methods, British Pharmacopeia methods, and International Pharmacopeia methods. Other reported methods that are used for the analysis of the drug are high-performance liquid chromatography, high-performance liquid chromatography-mass spectrometry, and polarography. Metabolism, pharmacokinetics, and stability studies on dacarbazine are also included. Reviews of some analytical methods and physicochemical properties of the drug as well as the most important enzymes that are involved in the prodrug activation are provided. Sixty-four references are listed at the end of this monograph.

A phase 1-2 study of imexon plus dacarbazine in patients with unresectable metastatic melanoma

BACKGROUND

Imexon (Amplimexon) is an aziridine compound that increases reactive oxygen species, disrupts mitochondrial membranes, and induces apoptosis. Preclinical studies showed activity against melanoma cell lines and models in mice, and synergy with dacarbazine. The authors evaluated standard doses of dacarbazine combined with increasing doses of imexon to determine the maximal tolerated dose (MTD), toxicities, pharmacokinetics, and efficacy.

METHODS

Sixty-eight chemotherapy-naive melanoma patients (1 inoperable stage III and 67 stage IV) were treated with dacarbazine (250 mg/m2) and imexon (570-1300 mg/m2), both daily for 5 days every 3 weeks.

RESULTS

There were 18 patients in the phase 1, and 50 in the phase 2 component of the study. The MTD of imexon with dacarbazine was 1000 mg/m2. Dose-limiting toxicities were pulmonary edema and hepatorenal failure. At the MTD, therapy was well tolerated. The most common toxicities (any grade) were vomiting, diarrhea, anemia, thrombocytopenia, anorexia, fever, and constipation. Among 68 patients, there were 7 treatment-related serious adverse events. Partial response and stable disease rates were 5.9% and 25% for all subjects and 2% and 30% for the phase 2 patients, respectively. Median progression-free and overall survival of all patients were 2.0 and 11.7 months and 2 and 7.5 months for the phase 2 patients, respectively. Overall survival of the 31 patients with normal lactate dehydrogenase levels was >22.5 months. Pharmacokinetics of both drugs were similar to previous reports.

CONCLUSIONS

Imexon plus dacarbazine was well tolerated. The survival data suggest further evaluation in a randomized phase 2 study.

The relationship between six-month progression-free survival and 12-month overall survival end points for phase II trials in patients with glioblastoma multiforme

Common end points for phase II trials in patients with glioblastoma multiforme (GBM) are six-month progression-free survival (PFS6) and 12-month overall survival (OS12). OS12 can be accurately measured but may be confounded with subsequent therapies upon progression, whereas the converse is true for PFS6. Our goal was to assess the relationship between these end points separately for phase II trials in patients with newly diagnosed GBM and patients with recurrent GBM. Data were pooled from 11 North Central Cancer Treatment Group trials for patients with newly diagnosed GBM (n = 1348). All patients received radiotherapy and pharmaceutical therapy (before, during, or after radiotherapy). Data were pooled from 16 trials that used various pharmaceuticals in treating patients for recurrent GBM (n = 345). All trial regimens were declared nonefficacious by predefined criteria. Overall per-patient concordance was estimated with a kappa statistic. The relationship between OS12 and PFS6 across study arms was assessed by weighted linear regression and Pearson's correlation. Simulation was used to determine the agreement of study outcomes when using PFS6 versus OS12 end points. Cox models with progression status as a time-dependent variable and Kaplan-Meier estimators were used to ascertain the association between progression-free survival status and overall survival. At present, 97% of the patients with newly diagnosed GBM and 95% of those with recurrent GBM have died. The PFS6 and OS12 were 43% and 41%, respectively, for patients with newly diagnosed disease and 9% and 14% for patients with recurrent disease. There was only moderate concordance between the end points on both the patient level and the study level. For the simulation studies, we established phase II efficacy criteria for each end point by using the pooled estimates of OS12 (PFS6) as historical controls. The study decisions made using PFS6 and OS12 were in agreement 88% and 90% of the time for the trials of newly diagnosed and recurrent disease, respectively. Finally, there was a strong association between progression-free survival status and overall survival. PFS6 seems to be a reasonable end point for phase II trials in patients with recurrent glioblastoma.

Therapeutic options for recurrent high-grade glioma in adult patients: Recent advances

Despite of postoperative radiotherapy plus temozolomide for newly diagnosed glioblastoma multiforme (GBM) and improvements in the molecular characterization of high-grade glioma, these tumors continue to relapse. We reviewed all clinical studies of re-treatment published between May 2000 and September 2005. In groups of highly selected patients with re-treatment for GBM, median survival reaches 26-27 months. Re-treatment was stereotactic radiotherapy (mostly with additional chemotherapy) or re-resection plus either photodynamic treatment, radioimmunotherapy and temozolomide, or systemic and local chemotherapy. Thus, intense local treatment was always a component of more successful strategies. Additional data suggest that chemotherapy is more efficacious when minimal residual disease is present, although the recent trials have not uncovered a clear regimen of choice. Early trials of immunotherapy and toxin-delivery demonstrate the feasibility of these approaches and encouraging median survival times. Response to erlotinib was more common if tumors had epidermal growth factor receptor gene amplification, protein overexpression and low levels of phosphorylated PKB/Akt. Individual tailoring of such strategies based on molecular profiling is hoped to improve the outcome.