High efficacy and low toxicity of weekly docetaxel given as first-line treatment for metastatic breast cancer

Optimisation of steroid prophylaxis schedules in breast cancer patients receiving docetaxel chemotherapy-a survey of health care providers and patients

PURPOSE

Despite the widespread use of steroid prophylaxis schedules for breast cancer patients receiving docetaxel chemotherapy, questions still exist regarding their optimal use. We surveyed health care providers and patients about their experiences with steroid prophylaxis.

METHODS

Two questionnaires were developed and circulated. One was presented to health care providers (chemotherapy nurses, pharmacists and medical oncologists) involved in the treatment of breast cancer and the second to patients who had received docetaxel chemotherapy for early stage breast cancer.

RESULTS

The health care providers' questionnaire was completed by 184 of 698 invitees: 92/171 (53.8 %) chemotherapy nurses, 56/284 (19.7 %) pharmacists and 36/243 (14.8 %) medical oncologists (overall response rate 26.4 %). Two steroid schedules were found to be the most commonly used: dexamethasone 8 mg BID for 6 doses, with either 3 (79 %) or 2 (11 %) doses taken before docetaxel administration. Suboptimal adherence to steroid premedication had been experienced by 98 % (177/181) of practitioners. Despite the presence of local treatment protocols in 65 % (119/183) of practitioners' institutions, 10 different strategies were commonly used when steroid premedication was taken incorrectly. The patients' questionnaire was completed by 72/87 (82.3 %) invitees. Respondents reported correctly taking their premedication 99 % (70/71) of the time. Patients felt steroids frequently caused side effects, the most common being sleep disturbance (35/72 = 49 %) and skin toxicity (16/72 = 22 %).

CONCLUSION

Suboptimal adherence to steroid premedication prior to docetaxel administration is a common clinical challenge. There appears to be discordance between the practitioner and the patient experience. A single, universally accepted and used protocol for both pre- and post-medication and management when premedication is not taken as prescribed could improve adherence.

Managing ixabepilone adverse events with dose reduction

Ixabepilone is a synthetic analogue of epothilone B approved for the treatment of patients with metastatic or locally advanced breast cancer in combination with capecitabine for cancer resistant to an anthracycline and a taxane, and as monotherapy for cancer resistant or refractory to anthracyclines, taxanes, and capecitabine. The principal dose-limiting adverse events (AEs) of ixabepilone's standard dose (40 mg/m(2) administered by 3-hour infusion once every 3 weeks) are peripheral neuropathy, neutropenia, and fatigue. An effective strategy to manage ixabepilone-related AEs is dose reduction by 20% (from 40 to 32 to 25 mg/m(2)); this does not appear to affect treatment efficacy and enables continuation of treatment after recovery (grade 1 or resolved). When appropriate, treatment can be restarted with a 20% dose reduction (to 32 mg/m(2)). For heavily pretreated patients, especially those with a low performance status, 32 mg/m(2) is an appropriate initial dose; the dose of capecitabine should also be lowered by 20%. Weekly ixabepilone (15-20 mg/m(2) on days 1, 8, and 15 every 28 days) may have an improved tolerability profile, but prospective studies with a large number of patients are required to determine whether it has therapeutic benefit comparable with the current approved regimen. More information is required on dosage and scheduling of ixabepilone in combination with other agents, including novel targeted therapies.

Weekly docetaxel in the treatment of metastatic breast cancer

Breast cancer is the most frequent tumor among women worldwide and is the second cause of cancer-related mortality in the US. Metastatic breast cancer (MBC) accounts for less than 10% of newly diagnosed breast cancer patients and about 30% of early breast cancer patients will develop recurrent, advanced, or metastatic disease. It remains an incurable illness and the primary goal of its management is palliative. Several agents are active for the first-line treatment of MBC. The taxanes, paclitaxel and docetaxel, represent the standard of care for the treatment of these patients. Among the various schedules, docetaxel can be administered weekly, achieving similar efficacy results with lower toxicity compared with conventional schedules. Weekly docetaxel (25–40 mg/m²) has been widely tested in several phase I and II studies both as a single agent and in multichemotherapy regimens, reaching overall response rates ranging from 26% and 86% or 20% and 73% with docetaxel alone or in combination, respectively, depending on doses, associations, and line of treatment. Overall, published data support the administration of weekly docetaxel for the treatment of MBC patients even if data from phase III randomized trials are still lacking.

Tumor, tissue, and plasma pharmacokinetic studies and antitumor response studies of docetaxel in combination with 9-nitrocamptothecin in mice bearing SKOV-3 human ovarian xenografts

PURPOSE

We evaluated the antitumor activity of two different schedules of docetaxel and 9-nitrocamptothecin (9NC) in mice bearing human SKOV-3 ovarian carcinoma xenografts and evaluated the plasma, tissue, and tumor disposition of each agent alone and in combination.

EXPERIMENTAL DESIGN

The following treatment groups were evaluated: (1) docetaxel 10 mg/kg IV on days 0 and 7; (2) 9NC 0.67 mg/kg PO qdx5dx2wk; (3) 9NC 0.67 mg/kg PO qdx5dx2wk in combination with docetaxel 10 mg/kg IV on days 0 and 7; and (4) 9NC 0.67 mg/kg PO qdx5dx2wk in combination with docetaxel 10 mg/kg IV on days 4 and 11; (5) vehicle controls for each agent; and (6) no treatment controls.

RESULTS

All treatment regimens produced significant antitumor activity as compared with control groups (P < 0.05). Docetaxel administered on days 0 and 7 or on days 4 and 11 in combination with 9NC resulted in similar antitumor activity (P > 0.05). High docetaxel concentrations in tumor were maintained at late time points as compared with plasma and tissues with the retention of docetaxel at 24 h being 132-fold and 15-fold higher in tumor than in plasma and liver, respectively. After administration of 9NC alone, the ratio of the 9-aminocamptothecin (9AC) area under the concentration versus time curve (AUC) to 9NC AUC in plasma and tumor was 0.15 and 1.34, respectively.

CONCLUSIONS

The combination of docetaxel and 9NC was effective against SKOV-3 xenografts. The lack of a difference in sequence-dependent antitumor activity may reflect the sensitivity of the SKOV-3 xenograft to 9NC. The factors associated with tumor-specific retention of docetaxel and the ratio of 9NC to 9AC in tumors is unknown.

Improvement of Safety Profile of Docetaxel by Weekly Administration in Patients with Metastatic Breast Cancer

BACKGROUND

This is a retrospective cohort study on the safety and efficacy profiles of weekly docetaxel at varying doses in patients with pretreated metastatic breast cancer.

PATIENTS AND METHODS

Twenty-five anthracycline-pretreated patients received docetaxel administered on a weekly basis, as a one-hour infusion, at various dosage levels (25, 30, 35, 40 mg/m2) depending on their baseline Karnofsky index. Each 8-week cycle consisted of 6 weeks of drug infusion, followed by a 2-week rest period.

RESULTS

Of the 25 patients investigated, none achieved complete response (CR), while 9 patients showed partial response (PR), which corresponds to an overall response rate of 36%. Five patients (20%) maintained stable disease (SD), whereas 11 patients (44%) suffered tumor progression (PD) during treatment. Clinical response (defined as PR+SD) was achieved in 14 patients (56%). Median time to progression was 231 days (95% CI, 187-275). The baseline Karnofsky index was 87% +/- 9% (range: 70-100). Patients pretreated with anthracyclines only tended to have a better response than anthracycline/paclitaxel-pretreated patients (n = 6, p = 0.054). Higher dosages were associated with neurotoxicity, skin/nail toxicity, leukopenia, nausea/vomiting, fatigue/asthenia, peripheral edema, but not with diarrhea and alopecia. The cumulative dose per patient was largest for a weekly docetaxel dosage of 35 mg/m2 and almost as large for 30 mg/m2.

CONCLUSION

Balancing toxicity vs. efficacy/cumulative dosage delivered, our results support weekly administration of docetaxel at dosages of 30-35 mg/m2 in metastatic breast cancer. Response in patients pretreated with anthracyclines and taxanes may be poorer than in those pretreated with anthracyclines only.

A phase II study of weekly docetaxel in patients with anthracycline pretreated metastatic breast cancer

BACKGROUND

Docetaxel has significant activity in metastatic breast cancer and weekly schedules are associated with less myelosuppression than 3-weekly schedules. We evaluated the toxicity and the activity of weekly docetaxel in anthracycline-pretreated patients.

PATIENTS AND METHODS

A total of 42 patients were studied. Treatment consisted of docetaxel 35 mg/m2 weekly as a 30-min infusion for 6 weeks followed by a 2-week rest, with dexamethasone 8 mg i.v. pre-medication and 4 mg orally 12-hourly for 48 h following treatment.

RESULTS

The median age of the patients was 53 years (range 34-74). Twenty-six (62%) patients had received prior chemotherapy for advanced disease. Patients received a median 10 weeks of treatment (range 1-24). 11 had a partial response (ORR 26%; 95% CI 13-39%), five of whom had relapsed <12 months since the end of previous anthracycline-based chemotherapy. In addition six patients (14%) had stable disease for >16 weeks. Myelosuppression was rare with only 2 patients (5%) experiencing grade 3 neutropenia (no grade 4 neutropenia). Non-haematological grade III toxicities were as follows: fatigue 17%, neuropathy 0%, hyperlacrimation 5%, stomatitis 7%, diarrhoea 14%, and cutaneous toxicity 19%. Skin toxicity consisted of limb/palmar-plantar erythematous reactions, or fixed-plaque erythrodysaesthesia.

CONCLUSIONS

Weekly docetaxel has moderate activity in women with anthracycline pre-treated breast cancer. Although the level of myelosuppression is lower than 3-weekly regimens, this weekly regimen cannot be recommended due to the significant non-haematological toxicities associated with the treatment.

Docetaxel: a review of its use in metastatic breast cancer

Docetaxel (Taxotere), a cytotoxic taxane, is an antimicrotubule agent effective in the treatment of patients with breast cancer. The clinical profile of docetaxel as an effective cytotoxic agent in the treatment of metastatic breast cancer is well established. As yet, no single standard regimen has been identified as optimal for the treatment of patients with metastatic breast cancer after failure of prior chemotherapy. However, the efficacy of docetaxel monotherapy administered every 3 weeks as a 1-hour infusion is similar to or better than that of doxorubicin, paclitaxel and fluorouracil plus vinorelbine, and better than that of methotrexate plus fluorouracil or mitomycin plus vinblastine. Although docetaxel is associated with neutropenia and other adverse events, its overall tolerability profile is generally acceptable in the majority of patients. Docetaxel, therefore, is an effective option in the treatment of patients with metastatic breast cancer after failure of prior chemotherapy.

Docetaxel in the treatment of breast cancer: current experience and future prospects

It has become clear over the past 10 years that docetaxel, a semisynthetic taxoid antineoplastic agent, is among the most promising compounds to have been developed in the 1990s for the treatment of breast cancer. Data indicate that this drug became standard therapy in the treatment of patients with metastatic disease who have failed anthracycline treatment, and secondarily showed very encouraging results in the first-line metastatic setting either in monochemotherapy or when docetaxel was combined with an anthracycline. More recently, docetaxel also became one of the standard therapies in the adjuvant and neoadjuvant settings, and a promising partner for novel biologic therapies. Current research is further exploring the effect of docetaxel on outcome of early breast cancer in order to fully determine the extent that this chemotherapeutic agent will change the natural history of breast cancer.