Carboplatin was given as a 30-min infusion to 11 ovarian cancer patients at doses of 170-500 mg/m2. The ages, weights, and creatinine clearances (Clcr) ranged from 44 to 75 years, from 44 to 74 kg, ...and from 32 to 101 ml/min, respectively. Plasma, plasma ultrafiltrate (PU), and urine samples were obtained at appropriate times for 96 h and were analyzed for platinum. The PU and urine were also analyzed for the parent compound by HPLC. In patients with a Clcr of about 60 ml/min or greater, carboplatin decayed biexponentially with a mean t1/2 alpha of 1.6 h and a t1/2 beta of 3.0 h. The mean (+/- SD) residence time, total body clearance, and apparent volume of distribution were 3.5 +/- 0.4 h, 4.4 +/- 0.85 l/h, and 16 +/- 3 l, respectively. Cmax and AUCinf values increased linearly with dose, and the latter values correlated better with the dose in mg than in mg/m2. No significant quantities of free, ultrafilterable, platinum-containing species other than the parent compound were found in plasma, but platinum from carboplatin became protein-bound and was slowly eliminated with a minimal t1/2 of 5 days. The major route of elimination was excretion via the kidneys. Patients with a Clcr of 60 ml/min or greater excreted 70% of the dose as the parent compound in the urine, with most of this occurring within 12-16 h. All of the platinum in 24-h urine was carboplatin, and only 2%-3% of the dosed platinum was excreted from 48 to 96 h. Patients with a Clcr of less than about 60 ml/min exhibited dose-disproportional increases in AUCinf and MRT values. The latter were inversely related to Clcr (r = -0.98). Over a dose range of 300-500 mg/m2, carboplatin exhibited linear, dose-independent pharmacokinetics in patients with a Clcr of about 60 ml/min or greater, but dose reductions are necessary for patients with mild renal failure.
Response TUCK, DAVID P.; CANETTA, RENZO; FERRANTE, KAREN ...
JNCI : Journal of the National Cancer Institute,
04/1997, Letnik:
89, Številka:
8
Journal Article
The existing literature data base on carboplatin updated to June, 1985 has been reviewed. The compound seems to retain the same spectrum of activity as cisplatin, and a definite set of efficacy data ...is available for ovarian cancer of epithelial origin, small cell carcinoma of the lung and epidermoid carcinoma of the head and neck. A yet unpublished toxicity data base on carboplatin suggests that the compound has an improved therapeutic index over the parent compound, cisplatin, and that it does not seem inferior to another platinum coordination compound currently in clinical trials, iproplatin.
To determine (1) the impact of cyclophosphamide 600 mg/m2 on previously defined relationships between carboplatin area under the plasma concentration versus time curve (AUC) and indices of toxicity ...and response in women with advanced ovarian cancer; and (2) the relationships between indices of cumulative drug exposure and clinical outcomes.
Carboplatin AUC = dose/(creatinine clearance CCr + 25) and was calculated in 224 women who received carboplatin 300 mg/m2 and cyclophosphamide 600 mg/m2. The likelihood of grade 3 or greater myelotoxicity at any carboplatin AUC was compared with the likelihood of myelotoxicity at the same single-agent carboplatin AUC. The nadir count predicted using the University of Maryland single-agent carboplatin dosing formula was compared with the nadir count observed. Received and relative-received dose-intensity were calculated. Carboplatin exposure-intensity was defined by substituting cumulative carboplatin exposure for total dose. Relationships were sought between these indices and therapeutic outcomes.
The incidence of leukopenia and thrombocytopenia at any carboplatin AUC was greater for the two-drug combination than for single-agent carboplatin. The platelet nadir in 83% of patients was less than or equal to the nadir predicted for the same single-agent carboplatin AUC. Despite a narrow range of received dose-intensities, carboplatin exposure-intensity was distributed over a twofold range. There were no relationships between received and relative-received dose-intensity or carboplatin exposure-intensity and time to progression or survival.
Any carboplatin AUC when administered with cyclophosphamide 600 mg/m2 produces greater myelotoxicity than the same AUC of single-agent carboplatin. Received carboplatin dose-intensity underestimates the range of plasma drug exposure resulting from a fixed carboplatin dosing regimen. Whether higher carboplatin exposures can improve outcome requires prospective validation.
From August 1985 to November 1989 we conducted a trial of intraperitoneal (IP) carboplatin including a dose-escalation design in 25 women with advanced gynecologic malignancies. All had extensive ...prior therapy with cisplatin (median cumulative dose, 525 mg/m2). Carboplatin was administered IP in 2 L of 1.5% dextrose with a 4-hour dwell time every 4 weeks for six cycles at a starting dose of 200 mg/m2. Patients with reduced creatinine clearance (30 to 60 cc/min) were escalated more slowly than those with high (greater than 60 cc/min) clearance. Thrombocytopenia was dose-limiting and often more severe in patients with compromised renal function; there was no local drug toxicity. The median time of follow-up is 25 months. Complete responses (CRs) were documented in six of 23 assessable patients (26%) by repeat laparotomy, and an additional 11 patients (48%) had no disease evident by noninvasive restaging. Five of the CRs and six of the patients with no clinically evident disease have relapsed from 3 to 40 months after therapy. Six patients (26%) are alive and free of disease 8 to 47 (median, 20) months after therapy. IP carboplatin is effective against relapsed ovarian cancer, even after prior cisplatin therapy.
To evaluate the safety and hematologic tolerance of 2'-3'-dideoxyinosine (didanosine, ddI) in subjects with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex and prior hematologic ...intolerance to zidovudine.
A Phase I trial with two dose groups at a single-center, university-affiliated hospital ambulatory care center. Of 30 subjects enrolled, 21 had AIDS and nine had AIDS-related complex. All had CD4 lymphocyte counts less than 0.2 x 10(9)/L at entry. Didanosine was administered orally twice daily at a total daily dose of 750 mg or 1,500 mg for 12 weeks. Subjects who completed the 12-week study continued to receive ddI at the lower dose. All subjects were monitored for toxicity. Virologic and immunologic response markers were also measured.
For the group as a whole, there was no significant decrease in mean hemoglobin level or leukocyte or platelet counts. The dose-limiting toxicity was peripheral neuropathy. Other significant toxicities included pancreatitis and hypocalcemia. Uric acid elevations were common but were without clinical consequence. A sustained decrease in serum p24 antigen of at least 50% was noted in 42% of subjects who were p24 antigen-positive at entry. The mean CD4 lymphocyte count showed an initial increase that was not sustained over the 12-week study. All subjects remained anergic to skin testing.
Didanosine is well tolerated hematologically in some patients with prior significant hematologic intolerance to zidovudine. The toxicity profile for ddI differs from that of zidovudine and includes peripheral neuropathy and pancreatitis. Changes in CD4 lymphocyte number and HIV p24 antigen levels in some patients suggest antiviral activity of ddI in this population.
Ninety-two adult patients with AIDS or severe AIDS-related complex were treated with 2',3'-dideoxyinosine (didanosine; ddI) at dosages ranging from 0.8 to 66.0 mg/(kg·d) for at least 6 weeks in phase ...I trials. Potentially beneficial changes in weight (40% of patients), clinical signs or symptoms (40% of patients), CD4⁺ cell counts (25% of patients), and serum levels of HIV p24 antigen (50% of antigen-positive patients) were reported. Response rates tended to be higher among patients with AIDS-related complex and among those who had not received prior zidovudine therapy. A major response (improvement in at least one clinical parameter and in at least one laboratory marker) occurred in 29% of patients, and rates of major response tended to be higher in patients receiving higher dosages. The primary dose-limiting toxicity observed was peripheral neuropathy, which was observed with increasing frequency in patients receiving >20 mg/(kg·d). Of the other adverse effects, pancreatitis was possibly dose-dependent and hyperuricemia (without clinical gout) occurred only at high doses. Dosages of 250 mg and 375 mg of ddI twice daily will be used in extended phase II/III studies.
When used as first-line treatment for advanced ovarian cancer in phase III trials, single-agent carboplatin has produced clinical complete response rates comparable with or exceeding those of ...single-agent cisplatin. Phase I/II trials of combination chemotherapy have yielded overall objective response rates of 44% to 75% when carboplatin was combined with either cyclophosphamide or chlorambucil. In randomized phase III trials of carboplatin combination chemotherapy, response rates similar to those of cisplatin combinations have been achieved but with greatly reduced toxicities. The data from these phase I, II, and III trials show that carboplatin is as active as cisplatin in patients with advanced ovarian cancer and is associated with a significantly lower incidence and is associated with a significantly lower incidence of emesis, ototoxicity, peripheral neuropathy, and renal dysfunction. Thus, carboplatin should be considered the platinum compound of choice in the firstline treatment of advanced ovarian cancer.