Phase II trial of fludarabine phosphate in lymphoma: an effective new agent in low-grade lymphoma.

PURPOSE: In a phase II trial we investigated fludarabine phosphate (FAMP) as therapy for patients with relapsed lymphoma to determine its effectiveness and toxicity in this disease. PATIENTS AND METHODS: The 67 assessable patients had a median age of 56 years and had received a median of three chemotherapy regimens before treatment with FAMP. The starting dose was 25 mg/m2 administered intravenously over 30 minutes daily for 5 days every 3 to 4 weeks. RESULTS: High response rates were observed for follicular small cleaved-cell lymphoma (FSCCL) (62%), follicular mixed small- and large-cell lymphoma (80%), and follicular large-cell lymphoma (FLCL) (100%). Responses also occurred in small lymphocytic lymphoma (SLL) (33%), transformed lymphoma (33%), mycosis fungoides (40%), and Hodgkin's disease (25%). No responses were observed in other intermediate- or high-grade lymphomas (N = 20). Overall, there were five patients with a complete response, 23 patients with a partial response, and an overall response rate of 37%. Toxicity was primarily hematologic and infectious. No significant gastrointestinal, hepatic, renal, or neurologic toxicity occurred. CONCLUSIONS: We conclude that FAMP has major activity in follicular lymphoma. Fundamental research is needed to understand this differential efficacy in low-grade lymphoma yet lack of efficacy in intermediate- and high-grade lymphoma. Clinical investigations should be done using FAMP in varying dose schedules and in combination regimens.

Effect of intra-peritoneal fludarabine on rat spinal cord tolerance to fractionated irradiation.

The effect of fludarabine (9-beta-D-arabinosyl-2-fluoroadenine-5'- monophosphate), an adenine nucleoside analogue, on the tolerance of the spinal cord to fractionated irradiation was studied in a rat model. Anesthetized female Fisher 344 rats received irradiation to 2 cm of the cervical spine with a telecobalt unit (dose rate 1.14 Gy/min). Radiation was administered in two, four or eight fractions spread over a 48-h period with or without fludarabine. Animals assigned to combined therapy received two daily intraperitoneal injections of fludarabine (150 mg/kg) given 3 h prior to the first daily radiation fraction. It was found that fludarabine reduced the iso-effect dose required to induce leg paresis at 9 months after irradiation for all fractionation schedules. Dose modification factors of 1.23, 1.29 and greater than 1.27 were obtained for two, four and eight fractions, respectively. Fitting the data with the direct analysis method of Thames et al. with an incomplete repair model [18] showed that the potentiating effect of fludarabine may be mediated through reduction in the number of 'tissue-rescuing units' (InK). Alpha and beta values were slightly but not significantly decreased, whereas the alpha/beta ratio was unchanged. These features suggest that fludarabine did not significantly inhibit cellular repair processes but rather reduced the spinal cord tolerance by a fixed additive toxic effect on the same target cells. In rodent models, the combination of fludarabine and fractionated radiation has previously been found to yield a therapeutic gain, i.e., the drug enhanced tumor response to a greater extent than it reduced normal tissue tolerance.(ABSTRACT TRUNCATED AT 250 WORDS)

Gemcitabine modulation of alkylator therapy: a phase I trial of escalating gemcitabine added to fixed doses of ifosfamide and doxorubicin.

BACKGROUND: The authors investigated the maximum tolerated dose (MTD) and dose limiting toxicity (DLT) associated with the addition of a biomodulating dose of gemcitabine to an established regimen of ifosfamide and doxorubicin as part of a program to explore the potential of low-dose gemcitabine to modulate the activity of alkylating agents. METHODS: A Phase I trial was carried out in a population of patients with bladder or pelvic carcinoma for whom no standard therapy was available. Doses of ifosfamide and doxorubicin were held fixed at 2 g/m(2) for 4 days and 20 mg/m(2) for 3 days, respectively. Gemcitabine was given on Day 2 and Day 4 at doses of 90 mg/m(2), 150 mg/m(2), and 200 mg/m(2) per dose. RESULTS: A total of 18 patients received 53 courses of therapy. Myelosuppression was dose limiting. Nonhematologic toxicity also was significant, with 10 of 18 patients experiencing toxicity of Grade 3 or greater. For previously untreated patients with an intact performance status, the MTD for gemcitabine in this context was at least 150 mg/m(2) per dose. According to an intent-to-treat analysis, 11 of 18 patients demonstrated a clinically significant response to this regimen. CONCLUSIONS: The regimen of ifosfamide and doxorubicin with the addition of gemcitabine was significantly toxic but has promising activity. Based on the observed activity and the generally reversible nature of the toxicity, the authors have initiated a Phase II trial of this regimen in patients with untreated, metastatic urothelial carcinoma.

Mitoxantrone and high-dose cytosine arabinoside in refractory acute myelogenous leukemia.

Forty-four patients with a diagnosis of refractory or relapsed acute myelogenous leukemia received salvage chemotherapy with high-dose cytosine arabinosine 3 g/m2 intravenously over 2 hours every 12 hours for six doses and mitoxantrone 5 mg/m2 intravenously daily for 5 days. Overall 16 patients (36%) had a complete remission; 16 patients (36%) had resistant disease; and 12 (27%) died during induction therapy. The most significant predictive factor for remission was the duration of first remission: the response rate was 17% for patients whose first remission duration was shorter than 12 months (including those who did not achieve a first remission), 45% for those with a first remission lasting between 12 to 18 months, and 69% for those with longer remission durations (P = 0.008). Other predictive factors for higher response rates were a younger age group, a good performance status, and a favorable or diploid karyotype. The median survival from start of therapy was 4 months for the total population and 10 months for patients with remission. Serious side effects including pulmonary toxicity and neurotoxicity occurred in less than 10% of patients. This incidence was significantly lower than previous high-dose cytosine arabinoside schedules of 3 g/m2 for nine to 12 doses (total dose, 27 to 36 g per course). Significant granulocytopenia and thrombocytopenia were universal resulting in fever or documented infections in 98% of patients. We conclude that the combination of high-dose cytosine arabinoside and mitoxantrone is an effective antileukemic regimen with acceptable toxicity. Future studies should incorporate it as part of the frontline induction or maintenance strategies in newly diagnosed patients with acute myelogenous leukemia.