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Susan Goodin

Publications and source records attributed to Susan Goodin.

22 records · Page 2Linked to original sources

Pharmacokinetics and pharmacodynamics of zoledronic acid in cancer patients with bone metastases.

The pharmacokinetics, pharmacodynamics, and safety of zoledronic acid (Zometa), a new-generation bisphosphonate, were evaluated in 36 patients with cancer and bone metastases. Zoledronic acid (by specific radioimmunoassay) and markers of bone turnover were determined in plasma and urine after three consecutive infusions (qx28 days) of 4 mg/5 min (n = 5),4 mg/l5 min (n = 7),8 mg/15 min (n = 12), or 16 mg/15 min (n = 12). Zoledronic plasma disposition was multiphasic, with half-lives of 0.2 and 1.4 hours representing an early, rapid decline of concentrations from the end-of-infusion C(max) to < 1% of C(max) at 24 hours postdose and half-lives of 39 and 4526 hours describing subsequent phases of very low concentrations between days 2 and 28 postdose. AUC0-24 h and C(max) were dose proportional and showed little accumulation (AUC0-24 h ratio between the third and first dose was 1.28). Prolonging the infusion from 5 to 15 minutes lowered C(max) by 34%, with no effect on AUC0-24 h. Urinary excretion of zoledronic acid was independent of infusion duration, dose, or number of doses, showing average Ae0-24 h of 38% +/- 13%, 41% +/- 14%, and 37% +/- 17%, respectively, after 4, 8, and 16 mg. Only trace amounts of drug were detectable in post 24-hour urines. Renal clearance (Ae0-24 h)/(AUC0-24 h) was on average 69 +/- 28,81 +/- 40, and 54 +/- 34 ml/min after 4,8, and 16 mg, respectively, and showed a moderate correlation (r = 0.5; p < 0.001) with creatinine clearance, which was 84 +/- 23, 82 +/- 25, and 80 +/- 40 ml/min for the dose groups at baseline. Adverse events and changes from baseline in vital signs and clinical laboratory variables showed no relationship in terms of type, frequency, or severity with zoledronic acid dose or pharmacokinetic parameters. Zoledronic acid produced significant declines from baseline in serum and/or creatinine-corrected urine C-telopeptide (by 74%), N-telopeptide (69%), pyridinium cross-links [19-33%), and calcium (62%), with an increasing trend (by 12%) in bone alkalinephosphatase. There was no relationship of the magnitude and duration of these changes with zoledronic acid dose, Ae0-24 h, AUC0-24 h or C(max). The antiresorptive effects were evident within 1 day postdose and were maintained over 28 days across all dose levels, supporting monthly dosing with 4 mg zoledronic acid.

Adult↗

State-of-the-art treatment of metastatic hormone-refractory prostate cancer.

Initial therapy for advanced prostate cancer includes androgen ablation by surgical or medical castration. Still, nearly all men with metastases will progress to hormone-refractory prostate cancer (HRPC). Current U.S. Food and Drug Administration-approved agents for the treatment of HRPC include mitoxantrone and estramustine, although the vinca alkaloids and the taxanes have shown promising activity in single-agent phase II trials. Combinations of these agents induce a biochemical response in greater than 50% of patients, but the median duration of response is approximately 6 months. Overall survival of patients treated with these combinations is approximately 18-24 months. Studies are ongoing to develop novel therapies that target specific molecular pathways or mechanisms of chemotherapy resistance. Novel agents under development include growth factor receptor inhibitors, antisense oligonucleotides, bisphosphonates, and cell differentiating agents. Evaluation and incorporation of these agents into existing treatment regimens will guide us in the development of more active regimens in the treatment of HRPC.

Antineoplastic Agents, Hormonal↗

5-HT(3)-receptor antagonists for the treatment of nausea and vomiting: a reappraisal of their side-effect profile.

Nausea and vomiting can cause considerable distress and discomfort to patients undergoing chemotherapy, radiotherapy, or surgery. Several classes of antiemetic agents exist to combat these side effects, though the 5-HT(3)-receptor antagonists have become the first-line treatment choice for many cancer patients and are considered the "gold standard" in antiemetic therapy. Compared with the older generation antiemetic drugs, 5-HT(3)-receptor antagonists are effective, well tolerated, and associated with few side effects. However, emerging differences among these agents suggest that the incidence and/or intensity of adverse events should not be regarded as a class effect. The side-effect profile of any supportive care therapy is particularly important in certain subgroups of patients, including pediatric patients and the elderly, as well as those suffering comorbid conditions, such as cardiovascular disease and renal or hepatic impairment. Indeed, dolasetron is associated with cardiovascular effects, and thus, should be used with extreme caution in patients who suffer from or may develop prolongation of cardiac conduction intervals. Ondansetron, on the other hand, is associated with a greater incidence of central nervous system side effects than either dolasetron or ondansetron, and pharmacokinetic parameters are affected in patients with hepatic impairment, thereby requiring dose adjustments. Clinicians are encouraged to evaluate patients on an individual basis when choosing which 5-HT(3)-receptor antagonist to prescribe.

Antiemetics↗