A phase I and pharmacokinetic study of exisulind and docetaxel in patients with advanced solid tumors.

PURPOSE: Exisulind (sulindac sulfone, FGN-1, Aptosyn) is a sulindac metabolite that induces apoptosis via inhibition of cyclic GMP-phosphodiesterase. This agent demonstrated tumor growth inhibition in rodent models of colon, breast, prostate, and lung carcinogenesis. In an orthotopic model of human non-small-cell lung cancer, the combination of exisulind and docetaxel prolonged survival in athymic nude rats, forming the basis of this phase I combination study. EXPERIMENTAL DESIGN: This study evaluated the toxicity and pharmacokinetics of combining exisulind (150-250 mg) given orally twice daily and docetaxel (30-36 mg/m2) administered intravenously on days 1, 8, and 15 of a 4-week cycle. RESULTS: Twenty patients with a range of advanced solid tumors (median age, 59 years; age range, 35-77 years; median performance status, 1) received a total of 70 courses. Observed adverse events were mild to moderate, and there was no dose-limiting toxicity at any level. Grade 3 gastrointestinal toxicities were present in 10 of the 70 cycles (10%) and included nausea, vomiting, dyspepsia, and elevated alkaline phosphatase. Neutropenia was present in four cycles in patients treated with a docetaxel dose of 36 mg/m2. Pharmacokinetic analysis did not demonstrate a clear effect of exisulind on docetaxel pharmacokinetics and vice versa. Relationships were evident between the plasma concentration of exisulind and the development of grade 2 or greater toxicities. One third of patients maintained stable disease for 3 to 12 cycles, but no objective responses were observed. CONCLUSIONS: The combination of docetaxel (36 mg/m2, weekly) and exisulind (500 mg/d) was reasonably well tolerated, and it is undergoing phase II testing in patients with non-small-cell lung cancer.

Angiogenesis inhibitors in clinical development for lung cancer.

The use of tumor angiogenesis as a therapeutic target is based on extensive literature showing the dependence of tumors on the process of angiogenesis for growth, invasion, and metastasis. Seminal work performed by Folkman three decades ago determined that tumors beyond the size of approximately 2 mm require angiogenesis for subsequent growth and development. This basic hypothesis stimulated research in the field of angiogenesis and has resulted in the identification of factors that both enhance and inhibit this "angiogenic switch." The intent of this article is to present data on several angiogenesis inhibitors that are currently undergoing clinical evaluation in cancer patients. These agents may be particularly useful in the treatment of lung cancer, both as adjunctive therapy in early-stage or locally advanced disease, as well as in combination strategies with platinum-based therapy in metastatic disease. Although angiogenesis inhibitors have been in clinical trials for the past decade, there has been a shift in recent years towards the development of more mechanism-based and receptor-targeted agents. Interestingly, no antiangiogenic agent has been approved as such for use in cancer, perhaps because of the challenges involved in the clinical development of these novel agents. These include the potential requirement for long-term administration, difficulties in deriving biologically efficacious doses in early clinical trials, and the inability to use tumor regression as a primary endpoint in phase II trials.

Analysis of docetaxel pharmacokinetics in humans with the inclusion of later sampling time-points afforded by the use of a sensitive tandem LCMS assay.

PURPOSE: Docetaxel is a semisynthetic taxane derived from the needles of the European yew ( Taxus baccata) and it is an important chemotherapeutic agent in the treatment of recurrent ovarian, breast and non-small-cell lung cancers. Traditional dosing regimens with docetaxel involve doses of 60-100 mg/m(2) by infusion every 3 weeks. Now weekly low-dose (30-36 mg/m(2)) regimens are being evaluated in phase I trials. Such low-dose studies require a more sensitive, specific and rapid assay of docetaxel in biological fluids for the determination of pharmacokinetic parameters. Because docetaxel is primarily metabolized by CYP3A4 and is highly protein-bound in the plasma, there is potential for drug-drug interactions and high interpatient variability in pharmacokinetics. Therefore, pharmacokinetic studies are an important component to understanding the therapeutic variability of docetaxel-containing chemotherapeutic regimens. METHODS: To this end, we developed an analytical assay for docetaxel based upon tandem LCMS and paclitaxel as an internal standard. The sensitivity of the new assay allowed us to monitor plasma levels of docetaxel out to 48 h after the end of the infusion in patients enrolled in a phase I trial of exisulind (orally, twice daily) receiving weekly docetaxel doses of 30 or 36 mg/m(2) where plasma docetaxel levels are below the lower limit of quantitation for traditional HPLC/UV-based assays at later time-points. RESULTS: The inclusion of the 48-h time-point had significant effects on the calculated pharmacokinetic parameters when using either a three-compartment or non-compartmental analysis. The terminal half-life was significantly increased when the 48-h time-point was included in the pharmacokinetic analysis, and the use of model parameters derived with the inclusion of the 48-h time-point were able to more accurately predict plasma levels at later times. CONCLUSIONS: The results reflect the importance of accurate and sensitive analytical methods for the determination of pharmacokinetic parameters and the effect of this later time-point on docetaxel pharmacokinetic modeling. Further, with the increased use of weekly docetaxel in combination with other agents, the inclusion of these later sampling time-points and sensitive methods for drug level determinations are important components in the description of pharmacokinetic drug interactions.

A phase I study of bortezomib, etoposide and carboplatin in patients with advanced solid tumors refractory to standard therapy.

PURPOSE: To evaluate the toxicity, pharmacological, and biological properties of the combination of bortezomib, etoposide, and carboplatin in adults with advanced solid malignancies. PATIENTS AND METHODS: Patients received escalating doses of bortezomib, etoposide, and carboplatin every 21 days. Surrogate markers of angiogenesis were evaluated. RESULTS: Twenty-four patients received 64 courses of therapy. The most common treatment-related adverse events were myelosuppression. Dose-limiting grade 3 and 4 neutropenia and thrombocytopenia were observed when bortezomib was given on days 1, 4, 8, 11. With revised dosing, the maximum tolerated dose (MTD) of bortezomib 0.75 mg/m(2) (days 1, 8), etoposide 75 mg/m(2) (days 1-3), and carboplatin AUC 5 (day 1) was well tolerated, and are the recommended doses for further studies with this combination. No objective responses were observed, however stable disease was noted for greater or equal to four cycles in nine highly refractory patients.

A phase I and pharmacokinetic study of silybin-phytosome in prostate cancer patients.

Silibinin is a polyphenolic flavonoid isolated from milk thistle with anti-neoplastic activity in several in vitro and in vivo models of cancer, including prostate cancer. Silybin-phytosome is a commercially available formulation containing silibinin. This trial was designed to assess the toxicity of high-dose silybin-phytosome and recommend a phase II dose. Silybin-phytosome was administered orally to prostate cancer patients, giving 2.5-20 g daily, in three divided doses. Each course was 4 weeks in duration. Thirteen patients received a total of 91 courses of silybin-phytosome. Baseline patient characteristics included: median age of 70 years, median baseline prostate specific antigen (PSA) of 4.3 ng/ml, and a median ECOG performance status of 0. The most prominent adverse event was hyperbilirubinemia, with grade 1-2 bilirubin elevations in 9 of the 13 patients. The only grade 3 toxicity observed was elevation of alanine aminotransferase (ALT) in one patient; no grade 4 toxicity was noted. No objective PSA responses were observed. We conclude that 13 g of oral silybin-phytosome daily, in 3 divided doses, appears to be well tolerated in patients with advanced prostate cancer and is the recommended phase II dose. Asymptomatic liver toxicity is the most commonly seen adverse event.

A phase II study of Irofulven (MGI 114) in patients with stage IV melanoma.

Sixteen patients with stage IV melanoma, who were heavily pretreated, received 11 mg/m2/day of intravenous Irofulven for five consecutive days every 28 days. There were no objective tumor responses, although one patient exhibited stable disease after 4 cycles. The most common toxicities were grade 1/2 nausea, vomiting, fatigue, anemia, and thrombocytopenia. One patient required a dose reduction for an elevated creatinine while another patient required cessation of treatment because of acute ataxia that may have been related to Irofulven. Based upon these data, Irofulven does not demonstrate significant antitumor activity to warrant further investigation in advanced melanoma.