Mitoxantrone as first line cytotoxic therapy in advanced breast cancer: preliminary results of a phase II study

Application of neoadjuvant chemoendocrine therapy for operable breast carcinomas

The use of neoadjuvant chemotherapy in primary breast cancer is based on sound theoretical, experimental and clinical principles. Higher objective response rates have been seen in patients with locally advanced breast carcinoma. Furthermore, when used in patients with operable breast carcinomas, sufficient downstaging has been achieved to allow for breast conservation surgery in patients who would otherwise require a mastectomy. This has been achieved without an increase in local recurrence. The anthracenedione mitoxantrone was used as part of the 3M/2M regimen in the neoadjuvant trial at the Royal Marsden Hospital, which was the first to establish within the setting of a clinical trial, the reduction in mastectomy requirements. This regimen combined high objective response rate with low symptomatic toxicity. An important benefit of neoadjuvant therapy is the opportunity to study in vivo the effects of treatment in primary breast carcinomas. The use of the primary tumour as a marker of response prior to surgery may, in the future, allow for the optimization of therapy for individual patients.

Phase II evaluation of mitoxantrone plus cis-platinum in patients with advanced breast cancer. A Southwest Oncology Group study

The Southwest Oncology Group studied the response rate and toxicity of mitoxantrone (7.5 or 10 mg/m2 to 12.0 mg/m2) and cis-platinum (100 mg/m2) in 30 patients with advanced breast cancer as second-line therapy. There were 2 partial responses in 29 eligible patients. Toxicity was considerable, with 27 patients having grade 3 or 4 toxicity. Grade 3-4 toxicity included vomiting, thrombocytopenia, granulocytopenia, leukopenia and anemia. The combination of mitoxantrone plus cis-platinum has minimal activity as second-line therapy in metastatic breast cancer.

Early assessment of a new anticancer drug analogue--are the historical comparisons obsolete? The French experience with pirarubicin

Data of all phase II studies of pirarubicin (THP-doxorubicin) have been analysed for toxicity or activity in breast cancer and compared with published reports on doxorubicin, epirubicin or mitoxantrone used as single drugs. A graph of the 95% confidence intervals for each event was used. The results suggest that pirarubicin is as effective as other intercalating drugs in breast cancer and grossly better tolerated than doxorubicin, especially alopecia and cumulative cardiotoxicity. The equimyelotoxic doses of each drug were also estimated. The methodology and the validity of such historical comparisons is discussed: they cannot replace prospective randomised phase III studies, and do not allow definitive conclusions. However, most comparative trials of anticancer drug analogues cannot answer the right questions because their objectives are not adequate (especially for equiefficacy). But early evaluation by historical comparisons can help the conception of phase III studies.

Mitoxantrone. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in the chemotherapy of cancer

Mitoxantrone is a dihydroxyanthracenedione derivative which as intravenous mono- and combination therapy has demonstrated therapeutic efficacy similar to that of standard induction and salvage treatment regimens in advanced breast cancer, non-Hodgkin's lymphoma, acute nonlymphoblastic leukaemia and chronic myelogenous leukaemia in blast crisis; it appears to be an effective alternative to the anthracycline component of standard treatment regimens in these indications. Mitoxantrone is also effective as a component of predominantly palliative treatment regimens for hepatic and advanced ovarian carcinoma. Limited studies suggest useful therapeutic activity in multiple myeloma and acute lymphoblastic leukaemia. Regional therapy of malignant effusions, hepatic and ovarian carcinomas has also been very effective, with a reduction in systemic adverse effects. Mitoxantrone inhibits DNA synthesis by intercalating DNA, inducing DNA strand breaks, and causing DNA aggregation and compaction, and delays cell cycle progression, particularly in late S phase. In vitro antitumour activity is concentration- and exposure time-proportional, and synergy with other antineoplastic drugs has been demonstrated in murine tumour models. Leucopenia may be dose-limiting in patients with solid tumours, whereas stomatitis may be dose-limiting in patients with leukaemia. Other adverse effects are usually of mild or moderate severity although cardiac effects, particularly congestive heart failure, may be of concern, especially in patients with a history of anthracycline therapy, mediastinal irradiation or cardiovascular disease. Mitoxantrone displays an improved tolerability profile compared with doxorubicin and other anthracyclines, although myelosuppression may occur more frequently. Thus, mitoxantrone is an effective and better tolerated alternative to the anthracyclines in most haematological malignancies, in breast cancer and in advanced hepatic or ovarian carcinoma. Further studies may consolidate its role in the treatment of these and other malignancies.

Primary chemotherapy with mitoxantrone and prednisone in advanced breast carcinoma. A phase II study

Thirty-seven evaluable patients with progressive disseminated breast carcinoma were treated with a combination of mitoxantrone 14 mg/m2 i.v. every 3 weeks plus prednisone 20 mg/m2 p.o. daily with a reducing dose over several weeks. Thirteen of 37 patients (35%) achieved an objective response with two complete regressions. The median duration of response was 7 months and the median duration of survival 14 months. The cardiac function of all patients was monitored by serial left ventricular ejection fraction, at rest and after stress, and 3-monthly thereafter. Ten patients showed a deterioration in the ejection fraction after a minimum cumulative dose of 86 mg/m2 (six cycles), but only four developed clinical cardiac failure which was easily reversible after stopping mitoxantrone. Leucopenia was the dose-limiting toxicity. Nausea and/or vomiting were generally mild and transient. Alopecia was minimal. These results confirmed that this combination is effective and well tolerated in the treatment of disseminated breast carcinoma, and cardiotoxicity can be avoided with adequate monitoring of the left ventricular ejection fraction after six cycles of therapy (86 mg/m2).

The use of mitoxantrone plus cyclophosphamide as first-line treatment of metastatic breast cancer

Thirty-two patients with metastatic breast cancer who had not received prior chemotherapy for metastatic disease were entered into a trial of mitoxantrone 12 mg/m2 plus cyclophosphamide 600 mg/m2 given at three weekly intervals. Thirty-one patients are eligible for assessment. Response was seen in 65% (4/31 complete regression; 16/31 partial regression). Median duration of response was 6 months and median duration of survival was 10 months. Mitoxantrone + cyclophosphamide appears to be an active combination in treatment of metastatic breast cancer.

Phase I and II agents in cancer therapy: I. Anthracyclines and related compounds

Anthracycline antibiotics remain among the most potent anticancer drugs, but their efficacy is limited by the development of a dose-dependent irreversible cardiomyopathy and by the emergence of clones of tumor cells resistant to the effects of the drug. Modifications of the basic anthracycline structure have resulted in molecules that may share the activity of the parent compound, with amelioration of some toxicities, absence of cross-resistance, or activity against tumors insensitive to the parent drug. Epirubicin has a unique metabolic pathway, glucuronidation, that may result in more rapid plasma clearance and reduced toxicity as compared with doxorubicin. Epirubicin has demonstrated comparable activity to doxorubicin in breast cancer, with possibly reduced toxicity. Idarubicin is of interest because of its cytotoxic activity when given orally. Idarubicin has prolonged retention in the plasma and has equal cytotoxic activity to the parent compound. Idarubicin has demonstrated activity against acute leukemia and breast cancer; in the latter tumor category, some doxorubicin-resistant tumors have responded. Esorubicin is of interest because of its nearly absent cardiac toxicity. This agent has some activity against solid tumors and is currently being clinically tested. Aclacinomycin A is an anthracycline in which a trisaccharide is substituted for the aminosugar. Aclacinomycin A and the related compound marcellomycin are of interest as both cytotoxic and differentiating agents. Menogaril is an anthracycline with the aminosugar on the D ring; it does not exhibit cross-resistance with doxorubicin or cardiotoxicity. Mitoxantrone is a compound that is related to the anthracyclines but has a different mechanism of action. This agent has significant activity against acute leukemia and breast cancer and is currently being compared with doxorubicin. Amsacrine is another compound related to the anthracyclines that possesses major activity against acute leukemias. Minor modifications of the anthracycline molecule have had major impact on the biologic activity of these drugs. New anthracycline analogues with up to 100 times the potency of currently available anthracyclines are being developed for clinical testing, and these complex molecules retain a nearly unlimited potential for structural modification.

Mitoxantrone

Mitoxantrone is an anthraquinone antineoplastic agent with structural similarities to doxorubicin. It has a mechanism of action similar to the anthracyclines. Its primary elimination route is hepatic metabolism (only seven percent renal excretion) and it has a terminal half-life of approximately 40 hours. Mitoxantrone has significant activity in the treatment of metastatic breast cancer, acute leukemias, and non-Hodgkin's lymphoma. Some activity is reported in head and neck cancer, Hodgkin's, myeloma, bladder cancer, prostate cancer, non-small-cell lung cancer, and liver cancer. There is a suggestion of incomplete cross-resistance between mitoxantrone and the anthracyclines in certain neoplasms. Some activity is reported with mitoxantrone in patients refractory to the anthracyclines in breast cancer, acute leukemias, and non-Hodgkin's lymphomas. The usual doses used in solid tumors and in lymphomas are mitoxantrone 12-14 mg/m2 iv q3-4wk and in leukemias is mitoxantrone 12 mg/m2/d X 5 d iv for initial induction.

Mitoxantrone, methotrexate, and 5-fluorouracil combination chemotherapy as first-line treatment in stage IV breast cancer

Fifty patients with Stage IV breast cancer were entered into a prospective Phase II trial of combination chemotherapy that consisted of mitoxantrone (10 mg/m2), methotrexate (40 mg/m2), and 5-fluorouracil (600 mg/m2) given in a 3-weekly schedule. Objective response to treatment was seen in 18 of 48 assessable patients (38%). Responses were seen predominantly in the lung and pleura and the node and soft tissue sites of disease. The median duration of response was 7 months. Toxicity from treatment consisted predominantly of reversible leukopenia. Other toxicities such as nausea and alopecia occurred in less than one half of the patients in the study group. The combination was well-tolerated, and appears to be moderately effective.