Abstract BACKGROUND: Previous work has demonstrated that smokers have higher white blood cell counts than nonsmokers, but the effect of biochemically-confirmed smoking cessation on peripheral leukocyte counts has not been demonstrated in a large prospective study. METHODS: Subjects were healthy smokers enrolled in a trial of sustained-release bupropion for relapse prevention after smoking cessation. White blood cell (WBC) counts and absolute neutrophil counts (ANC) were measured at baseline, week 7 and week 52. Smoking status was assessed at weeks 7 and 52 by self-report and biochemically confirmed with expired air carbon monoxide levels. Multivariate analyses compared changes in WBC count and ANC between smokers who did and did not stop smoking, adjusting for treatment group, age, sex, and body mass index. RESULTS: Of 784 smokers enrolled, 461 had biochemically-confirmed tobacco abstinence after 7 weeks of bupropion; 429 were randomly assigned to receive continued bupropion or placebo until week 52. At baseline, the mean WBC count was 8.4 x 109/L (SD ±2.3) and the mean ANC was 5.3 x 109/L (SD ±1.9). The baseline WBC count and ANC were higher in smokers with greater tobacco exposure, measured by daily cigarette consumption and serum cotinine level. Between baseline and week 7, there was a significantly larger decrease in WBC count in continuously abstinent subjects compared with continuing smokers (adjusted p =.031). At 52 weeks, biochemically-confirmed continuously abstinent subjects, as compared with continuing smokers, had a greater decline from baseline in WBC count (1.2 x 109/L versus 0.1 x 109/L, p<0.001) and ANC (0.1 x 109/L versus 0.2 x 109/L, p<0.001). CONCLUSION: The WBC count and ANC of healthy smokers increase with increasing tobacco exposure. Biochemically-confirmed tobacco abstinence leads to a rapid and sustained decrease in WBC count and ANC, possibly reflecting a decrease in an underlying state of tobacco-induced inflammation.
A phase II study of ABT-510 for the treatment of metastatic melanoma
8041 Background: ABT-510 is a synthetic peptide analog of thrombospondin-1 demonstrating inhibition of VEGF/bFGF mediated human endothelial cell migration, proliferation, tube formation, cornea-neovascularization as well as inhibition of tumor growth in vivo (B16F10 melanoma). Having been found to be safe in phase I testing, ABT-510 has entered phase II trials. Presented are the results of a phase II study using ABT-510 for the treatment of stage IV melanoma. Methods: A two stage phase II clinical trial was conducted to assess the anti-tumor activity, safety profile and pharmacodynamics of ABT510 in patients with stage IV melanoma. Patients self-administered 100mg of ABT-510 subcutaneously twice/day. Therapy was continued in the absence of excessive toxicity or tumor progression. Primary endpoint was 18 week progression free survival rate. Enrolled were patients at least 18 years of age with measurable (RECIST) metastatic melanoma, ECOG performance status of 0–2 and normal pre-registration blood tests. Exclusion criteria included: cancer therapy less than 4 weeks prior to registration; failure to recover from prior therapy; brain metastases; significant recent bleeding; uncontrolled hypertension; and ongoing anti-coagulation. Pregnant or nursing women were not eligible. Results: Twenty-one patients (67% male) were enrolled with a median age of 55 years. Most patients had M1c disease (80%) and 62% had prior chemotherapy for stage IV melanoma. None of the patients were ineligible/canceled participation. After the first stage of the trial was complete, only 3 of the first 20 patients enrolled were progression-free at 18 weeks. Having not met the minimal clinical efficacy requirement (at least 7 of the first 20 patients progression-free at 18 weeks) the trial was closed to further accrual. Correlative laboratory studies suggested decreases in some of the measured parameters of angiogenesis (VEGFC, circulating endothelial cells) with no impact on immune homeostasis. Conclusions: Single agent ABT-510 therapy administered at 100mg twice/day to patients with previously treated metastatic melanoma did not demonstrate significant clinical efficacy. However, changes in measured parameters of angiogenesis suggest possible clinical efficacy with higher dosing or in combination with cytotoxic therapy. [Table: see text]
ABX-EGF monotherapy in patients (pts) with metastatic colorectal cancer (mCRC): An updated analysis
A phase I trial of the farnesyltransferase (FT) inhibitor, BMS-214662 (B) in combination with paclitaxel (P) and carboplatin (C) in patients with advanced cancer
Pharmacokinetics (PK) and pharmacodynamics (PD) of PD 0325901, a second generation MEK inhibitor after multiple oral doses of PD 0325901 to advanced cancer patients