Mean Dose Intensity Research Articles

Phase I study of phosphonacetyl-l-aspartate, 5-fluorouracil, and leucovorin in patients with advanced cancer

Low-dose phosphonacetyl-L-aspartate (PALA) may potentiate both 5-fluorouracil (5-FU) incorporation into RNA and thymidylate synthase inhibition by 5-fluorodeoxyuridylate (5-FdUMP). The gastrointestinal toxicity of 5-FU is not increased by PALA administration. Exogenous leucovorin, on the other hand, which enhances thymidylate synthase inhibition, appears to increase the clinical toxicity of 5-FU in a dose-dependent manner. As a result, the clinical use of high-dose leucovorin requires a marked dose reduction of 5-FU. Extracellular leucovorin levels of 1 microM suffice to maximize the enhancement of thymidylate synthase inhibition in several models. We conducted a trial to add leucovorin to the PALA/5-FU regimen. We chose a leucovorin dose that was predicted to yield end-infusion total reduced folate concentrations of 1 microM. The major endpoint was to determine the maximum tolerated dose of 5-FU in this combination. The regimen consisted of 250 mg/m2 PALA given on day 1 and, 24 h later, escalating 5-FU doses ranging from 1,850 to 2,600 mg/m2 admixed with 50 mg/m2 leucovorin and given by 24-h infusion. Courses were repeated weekly. A total of 24 patients with a median performance status of 1 were entered at three dose levels. Diarrhea was dose-limiting; 6/13 patients had grade II or worse diarrhea at 2,600 mg/m2. Dose modification resulted in a mean dose intensity of 2,300 mg/m2 at both the 2,600- and 2,300-mg/m2 dose levels. The 2,300-mg/m2 dose is suitable for phase II testing of this regimen. Three patients (two with breast cancer and 1 with sarcoma) had a partial remission. We measured steady-state concentrations (Css) of 5-FU in 23 patients. The mean Css increased with dose from 0.738 to 1.03 micrograms/ml. Total body clearance did not vary with dose in this range. Patients with grade II or worse diarrhea had a higher mean Css (1.10 +/- 0.19) than those with grade O or I toxicity (0.835 +/- 0.25, P < 0.02). Total bioactive folates (bound and free) were measured using a biological assay. Pretreatment values ranged from 2 to 52 nM and were not predictive of toxicity. End-infusion (23-h) values were somewhat lower than predicted and ranged from 400 to 950 nM. The risk of diarrhea was positively correlated with end-infusion total folate values. In a logistic regression analysis, total folate values obtained at 23 h were a more powerful predictor of diarrhea than were 5-FU Css values.(ABSTRACT TRUNCATED AT 400 WORDS)

Neurotoxicity is not enhanced by increased dose intensities of cisplatin administration

It is uncertain whether intensive dosing schedules of cisplatin, intended to attain a higher anti-tumour efficacy, alter the severity of cisplatin-induced neuropathy. We assessed the development of neuropathy in three groups of patients treated with cisplatin in different dosing schedules. The severity of neuropathy was determined by measurement of the vibration perception threshold (VPT) before treatment and during follow-up for 2-12 months after the last cycle. 66 patients were treated with an intensive weekly regimen of doses varying from 70 to 85 mg/m2 in 1 day (trial A), 21 patients with a 3-weekly combination chemotherapy containing cisplatin 75 mg/m2 in 1 day (trial B) and 20 patients with a 3-weekly regimen containing cisplatin 20 mg/m2 for 5 consecutive days (trial C). The mean dose intensity achieved was 59 mg/m2/week in trial A, 21 mg/m2/week in trial B and 33 mg/m2/week in trial C. The maximum post-treatment VPT correlated significantly with pretreatment VPT (P < 0.001) and with the cumulative dose of cisplatin (P < 0.001). Following correction for these two variables, the maximum posttreatment VPT did not show a statistically significant association with dose intensity. These results suggest that neuropathy is not related to dose intensity of cisplatin. This implies that treatment with more intensive dosing schedules, employing equal cumulative doses of cisplatin, does not result in a concomitant increase in neurotoxicity within a cumulative dose range of 280-675 mg/m2.

Vinorelbine (Navelbine) as a salvage treatment for advanced breast cancer

Vinorelbine (Navelbine), a new vinca alkaloid, is an effective drug in breast cancer. Our study was undertaken to assess the efficacy and tolerance of Navelbine in refractory advanced and/or metastatic breast cancer (AMBC). One hundred heavily pretreated patients with AMBC entered the study and were scheduled to receive 30 mg/m2 of Navelbine weekly by a 20 min i.v. infusion with dose adjustments according to tolerance. All patients had previously received at least one chemotherapy regimen including an anthracycline for advanced disease. Sixteen of the 100 assessable patients responded (1 complete response and 15 partial responses), for an overall response rate of 16% (IC 95: 8%-23%). The median duration of response was 5 months (3-18). Responses were seen in lymph nodes (13/27), breast (11/34), soft tissue and skin (13/36), lung (3/14) and liver (2/25), but not in bone metastases. The main toxicities (WHO grade > or = 3) were granulocytopenia and anemia in, respectively, 51% and 9% of all 100 eligible patients. Thrombocytopenia and other non-haematological toxicities consisting of peripheral neuropathy, constipation, nausea/vomiting, alopecia and phlebitis were rare and mild. Vinorelbine is an active drug in AMBC, particularly in breast, lymph nodes and skin/soft tissue sites, with an excellent tolerance. Since the mean dose intensity was 19.7 mg/m2/week, a dose of 20 mg/m2/week is recommended for heavily pretreated patients (radiotherapy and chemotherapy).

Carboplatin and α-2b interferon intraperitoneal combination as first-line treatment of minimal residual ovarian cancer. A pilot study

21 untreated ovarian cancer patients with stage III and minimal tumour size, were given weekly intraperitoneal (i.p.) carboplatin (150 mg/m 2) and α-2b interferon (IFN) (30 million U/m 2) for a total of 12 courses, from June 1989 to February 1993. To date, a total of 248 courses have been administered. Toxicity was seldom severe, although fever (179 courses), fatigue (141 courses) and other IFN-related side-effects were very frequent. No patient refused to continue treatment, but in 5 patients IFN dose had to be reduced, and in 1 it was discontinued. The IFN mean delivered dose intensity was 19.8 million U/m 2 week. Grade 3–4 myelotoxicity occurred in 7 patients (39 courses), but no deaths related to treatment occurred. The actual mean dose intensity of carboplatin was 121.5 mg/m 2 week. To date, 20 patients have completed treatment and are evaluable for response. Of 11 patients with tumour size ⩽ 5 mm, 10 (91%) achieved a pathological complete response (pCR) as did 4 9 (44%) of those with tumour > 5 mm at entry, for a 70% (95% confidence interval 50–90) overall pCR rate. At a median follow-up of 21 months (range 4–46), only one death occurred. The probability of being alive at almost 4 years was 91% in the entire group (100% in those with tumour size less than 5 mm). Only 1 of 14 patients who achieved a pCR relapsed. This i.p. combination seems a feasible approach to previously untreated ovarian cancer patients with minimal tumour burden. IFN dosage should be reduced to improve tolerance. In view of the very high pCR rate achieved in the group of patients with smaller tumours, a randomised trial is warranted to compare this approach to standard treatment in these patients.

A phase II study of days 1 and 8 cisplatin and recombinant alpha-2B interferon in advanced non-small cell lung cancer

Preclinical data from studies of human lung cancer xenografts suggest that the cytotoxic effects of cisplatin are enhanced by alpha-interferon. To verify the above observations, the authors initiated a Phase II trial in advanced non-small cell lung cancer (NSCLC). Cisplatin was given at 100 mg/m2 during a 28-day cycle in a divided day 1 and day 8 schedule. Starting on day 1, alpha-2B interferon was administered intramuscularly at a dose of 5 million units three times a week continuously for a minimum of 2 months. Between January 1989 and September 1989, 30 patients were evaluated for response and toxicity. According to the staging system proposed by Mountain, 20 patients had Stage IV disease, 7 had Stage IIIB disease, and 3 had Stage IIIA disease. Expression of neuron-specific enolase (NSE) and Leu-7 was immunohistochemically investigated to evaluate possible relationship to treatment response. The response rate was 13.3% (95% confidence interval [CI]: 1.2% to 25%). The four responders showed positivity for NSE, and two of them were positive for Leu-7. An average of three cycles was given. The mean dose intensity administered was 83% of the projected dose for cisplatin and 92% of the projected dose for alpha-2B interferon. A standard scale was used to assess interferon toxicity. Hematologic, renal, and systemic side effects were not significant. In advanced NSCLC the addition of alpha-2B interferon did not increase the cisplatin-induced response rate. Further studies should be performed to determine the real value of chemotherapy response in tumors showing positive immunoreactivity for neural markers such as NSE and Leu-7.

Chemotherapy of advanced ovarian cancer with 4'-O-tetrahydropyranyl doxorubicin and cisplatin: a randomized phase II trial with an evaluation of circadian timing and dose-intensity.

The efficacy and toxicity of the new anthracycline, 4'-0-tetrahydropyranyl doxorubicin (THP) (50 mg/m2 intravenous [IV] bolus) in association with cisplatin (100 mg/m2 IV as a 4-hour infusion) was assessed in 31 patients with advanced ovarian carcinoma. Twenty-eight patients were assessable for toxicity among whom 25 were assessable for response (International Federation of Gynecology and Obstetrics [FIGO] stage IIIa, four patients; IIIb, 15 patients; IV, six patients). Nine patients had received prior treatment. Patients were randomized to receive schedule (sch) A (THP at 6 hours, then cisplatin from 16 to 20 hours) or sch B (THP at 18 hours, then cisplatin from 4 to 8 hours). Sch A was hypothesized as less toxic since THP was best tolerated in the late rest span and cisplatin near the middle of the activity span in experimental studies. The rate of clinical complete response (CR) was 52%, that of partial response (PR) was 12%, and the overall clinical response rate (CR plus PR) was 64% (sch A, 73%; sch B, 57%). Median progression-free survival and survival times were, respectively, 10 and 19 months. Of 12 patients in clinical CR evaluated at second-look laparotomy, four had a pathological CR (33%), and three had microscopic residual disease (MD). The overall rate of pathological CR was 16%. Sch A was associated with less neutropenia (P = .10), thrombocytopenia (P less than .01), anemia (P less than .01), and renal toxicity (P less than .05) than sch B. Of four patients withdrawn for toxicity, three were on sch B (one death). Mean dose intensities (DIs) of THP and cisplatin, respectively, decreased by 30% and 47% over the five initial courses. Such decrease was significantly more pronounced for sch B than for sch A in previously untreated patients (P from 2-way analysis of variance [ANOVA] less than .01). THP-cisplatin is active against advanced ovarian cancer, and its toxicities can be significantly decreased by dosing THP in the early morning and cisplatin in the late afternoon as compared with THP in the evening and cisplatin the next morning.

Dose-intense weekly cyclophosphamide, methotrexate, 5-fluorouracil, vincristine and prednisolone (CMFP) in advanced breast cancer

Weekly chemotherapy with cyclophosphamide 80 mg m-2 day-1 p.o. continuously, methotrexate 35 mg m-2 week-1 i.v., 5-fluorouracil 500 mg m-2 week-1 i.v., vincristine 1.4 mg m-2 i.v. every two weeks and prednisolone 20 mg m-2 day-1 p.o. continuously (CMFVP) was prospectively studied in 45 previously untreated outpatients with advanced breast cancer to determine the feasibility of delivering a dose-intense regimen. Of 40 evaluable patients, complete response (CR) occurred in one patient, partial response (PR) in 20 (CR + PR 53%), stable in eight, progression in 11 and five were unevaluable for response. The median relapse-free survival for responders was 25 weeks and median survival for all patients was 31 weeks. The mean dose intensity relative to the Cooper regimen fell from 1.02 to 0.6 within the first 4 weeks of treatment and the median dose intensity achieved for all patients on study was only 0.52. Eighty-seven per cent of patients had treatment delays with a mean of 3.9 delays per patient and 71% had dose reductions. Neutropenia was the major toxicity with WHO grade 3 or 4 neutropenia (less than 1.0 x 10(9) l-1) in 62% of patients and three septic deaths while neutropenic. Dose-intense weekly CMFVP in this schedule cannot be delivered to previously untreated outpatients with advanced breast cancer.

Cisplatin Dose Intensity in Non-Small Cell Lung Cancer: Phase II Results of a Day 1 and Day 8 High-Dose Regimen

Between October 1985 and March 1987, 92 patients were registered on a phase II study of the Northern California Oncology Group investigating the importance of dose intensity in the treatment of advanced non-small cell lung cancer (NSCLC). Treatment consisted of high-dose cisplatin in hypertonic saline (200 mg/m2 on a 28-day cycle) given in a divided day 1 and day 8 schedule. The response rate among 76 assessable patients was 36% (27/76), with complete response (CR) in 8% (6/76) and partial response (PR) in 28% (21/76). If all patients receiving any drug therapy were considered, the overall response rate was 31% (27/87), with CR in 7% (6/87) and PR in 24% (21/87). Median survival times for all assessable patients and all patients receiving any therapy were 37 and 35 weeks, respectively. With the use of a protocol design specifying dose delays rather than dose reduction for toxicity, the mean dose intensity delivered was 47.2 mg/m2 per week, or 94% of projected. Compared with other dose-intensive regimens of cisplatin, this day 1 and day 8 schedule was relatively well tolerated, with peripheral neuropathy as the dose-limiting toxicity. The data on response and median survival times among patients receiving this single-agent therapy are encouraging. They support the potential importance of cisplatin dose intensity in the treatment of NSCLC. Whether these results represent a positive dose-response effect in NSCLC will be tested in a randomized comparative trial of high-dose versus standard-dose cisplatin therapy.