Phase II study of weekly docetaxel and capecitabine in patients with metastatic breast cancer

A multicenter phase II trial of docetaxel and capecitabine as salvage treatment in anthracycline- and taxane-pretreated patients with metastatic breast cancer

OBJECTIVE

To evaluate the efficacy and safety of docetaxel plus capecitabine (DC) combination as salvage treatment in anthracycline- and taxane-pretreated patients with metastatic breast cancer (MBC).

PATIENTS AND TREATMENT

Patients with MBC who had disease progression after initial chemotherapy with anthracyclines (n = 29; 100 %) and taxanes (n = 11; 37.9 %) were treated with oral capecitabine 950 mg/m(2) twice daily on days 1-14 and docetaxel 75 mg/m(2) on day 1 every 3 weeks. Nineteen (65.5 %) patients received this regimen as second line and 10 (34.5 %) as ≥3rd line of therapy. All patients were evaluable for response and toxicity.

RESULTS

Complete response occurred in two (6.9 %) patients and partial response in eleven (37.9 %) for an overall response rate of 44.8 % (95 % CI 26.7-62.9 %). Eleven women (37.9 %) had stable disease and five (17.2 %) progressive disease. Of the eleven patients previously treated with anthracyclines and taxanes, five (45.5 %) responded to DC combination. The median duration of response was 5.7 months (range 3.4-64.2), the median time to disease progression 9.3 months (range 1.2-58), and the median overall survival 25.5 months. No toxic death occurred. Neutropenia grade 4 occurred in 58.6 % of patients and three of them (10.3 %) developed neutropenic fever. Non-hematological toxicities were manageable with grade 3 hand-foot syndrome occurring in 6.9 % of the patients, fatigue in 3.4 %, and neurotoxicity in 3.4 %.

CONCLUSION

The DC combination is a valuable regimen as salvage treatment in anthracycline- or anthracycline and taxane-pretreated patients with MBC.

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.

Randomised, non-comparative phase II study of weekly docetaxel with cisplatin and 5-fluorouracil or with capecitabine in oesophagogastric cancer: the AGITG ATTAX trial

BACKGROUND

Docetaxel administered 3-weekly with cisplatin and 5-fluorouracil leads to better survival than does standard therapy in patients with oesophagogastric cancer, but leads to high rates of haematological toxicity. Weekly docetaxel is associated with less haematological toxicity. This randomised phase II study tested weekly docetaxel-based combination chemotherapy regimens, with the aim of maintaining their activity while reducing toxicity.

METHODS

Patients with histologically confirmed metastatic oesophageal or gastric carcinoma were randomised to receive weekly docetaxel (30 mg m(-2)) on days 1 and 8, cisplatin (60 mg m(-2)) on day 1, and 5-fluorouracil (200 mg m(-2) per day) continuously, every 3 weeks (weekly TCF, wTCF); or docetaxel (30 mg m(-2)) on days 1 and 8 and capecitabine (1600 mg m(-2) per day) on days 1-14, every 3 weeks (weekly TX, wTX).

RESULTS

A total of 106 patients were enrolled (wTCF, n=50; wTX, n=56). Response rates, the primary end point, were 47% with wTCF and 26% with wTX. Rates of febrile neutropenia were low in each arm. Median progression-free and overall survival times were 5.9 and 11.2 months for wTCF and 4.6 and 10.1 months for wTX, respectively.

CONCLUSION

Weekly TCF and TX have encouraging activity and less haematological toxicity than TCF administered 3-weekly. Weekly docetaxel-based combination regimens warrant further evaluation in this disease.

North Central Cancer Treatment Group (NCCTG) N0432: phase II trial of docetaxel with capecitabine and bevacizumab as first-line chemotherapy for patients with metastatic breast cancer

BACKGROUND

Docetaxel (T; Taxotere) with capecitabine (X) is active against metastatic breast cancer (MBC); bevacizumab (BV) has demonstrated efficacy with taxanes in the first-line setting. This study was conducted to assess the safety and efficacy of TX-BV in patients with MBC.

PATIENTS AND METHODS

In this single-arm, multicenter phase II study, patients received first-line bevacizumab 15 mg/kg and docetaxel 75 mg/m(2) on day 1 and capecitabine 825 mg/m(2) twice per day on days 1-14 every 21 days. Primary and secondary end points were tumor response rate (RR), overall survival (OS), progression-free survival (PFS), and toxicity.

RESULTS

A total of 45 assessable patients received TX-BV for a median of seven cycles. Two complete and 20 partial responses were observed (overall RR 49%); nine patients had stable disease >6 months, for a clinical benefit rate of 69%. Median response duration was 11.8 months. Median OS and PFS were 28.4 and 11.1 months, respectively. Grade 3/4 adverse events included hand-foot syndrome (29%), fatigue (20%), febrile neutropenia (18%), and diarrhea (18%). In cycles 3-10, median dose levels of docetaxel and capecitabine were 60 mg/m(2) and 660 mg/m(2), respectively.

CONCLUSION

TX-BV demonstrated significant activity; dose modifications were required to manage drug-related toxic effects.

Pharmacology and therapeutic efficacy of capecitabine: focus on breast and colorectal cancer

Capecitabine (N -pentyloxycarbonyl-5-deoxy-5-fluorocytidine), an oral prodrug of 5-fluorouracil, has provided compelling efficacy data for the treatment of metastatic breast cancer and stage III or IV colorectal cancer, both as monotherapy and in combination regimens. The preferential conversion of capecitabine to 5-fluorouracil in neoplastic tissues renders this fluoropyrimidine particularly appealing for clinical use. The enzyme thymidine phosphorylase, which mediates the final step of the capecitabine activation pathway, is expressed in higher concentration in neoplastic than in healthy tissues. This makes capecitabine more tumor specific than other chemotherapeutic agents. Accordingly, capecitabine is generally well tolerated. In particular, the incidence of myelosuppression and alopecia is low, and the most common side effects, hand-foot syndrome and diarrhea, are usually manageable. Given its good toxicity profile, capecitabine was assessed in combination with several chemotherapeutic or biologic agents. In addition, the observation that thymidine phosphorylase is upregulated after treatment with other anticancer drugs, namely taxanes, provided a rationale for the prominent antitumor activity recently observed for the combination of capecitabine with these agents. This review provides an evidence-based update of clinical trials investigating the role of capecitabine in the treatment of breast and colorectal cancer, with special emphasis on pharmacological and safety issues that form the basis of currently used schedules.

Synergistic interaction between trifluorothymidine and docetaxel is sequence dependent

Docetaxel is a microtubule inhibitor that has actions in the S and G(2)-M phase of the cell cycle. The pyrimidine trifluorothymidine (TFT) induces DNA damage and an arrest in the G(2)-M phase. TFT, as part of TAS-102, has been clinically evaluated as an oral chemotherapeutic agent in colon and gastric cancer. The aim of the present study was to determine the optimal administration sequence of TFT and docetaxel and to investigate the underlying mechanism of cytotoxicity. Drug interactions were examined by sulforhodamine B assays and subsequent combination index analyses, and for long-term effects the clonogenic assay was used. A preincubation with docetaxel was synergistic in sulforhodamine B (combination index 0.6-0.8) and clonogenic assays, and was accompanied by a time-dependent cell death induction (17-36%), the occurrence of polynucleation (22%), and mitotic spindle inhibition as determined by flow cytometry and immunostaining. Interestingly, administration of TFT followed by the combination displayed strong antagonistic activity, and was accompanied by less polynucleation and cell death induction than the synergistic combinations. Western blotting showed that the G(2)-M-phase arrest (25-50%) was accompanied by phosphorylation of Chk2 and dephosphorylation of cdc25c in the synergistic combinations. Together, this indicates that synergistic activity requires docetaxel to initiate mitotic failure prior to the activation of TFT damage signaling, whereas antagonism is a result of TFT cell cycle-arrested cells being less susceptible to docetaxel. Caspase 3 activation was low after docetaxel, suggestive of caspase-independent mechanisms of cell death. Taken together, our models indicate that combination treatment with docetaxel and TFT displays strong synergy when docetaxel is given first, thus providing clues for possible clinical studies.

Thymidine phosphorylase expression is associated with time to progression in patients receiving low-dose, docetaxel-modulated capecitabine for metastatic breast cancer

BACKGROUND

Preclinical data have indicated a synergistic interaction between docetaxel and capecitabine by means of taxane-induced up-regulation of thymidine phosphorylase (TP). On the basis of such premises, we conducted a phase II trial to determine the activity and tolerability of weekly docetaxel plus capecitabine in patients with metastatic breast cancer (MBC). Furthermore, we explored the relationship between TP tumor expression and benefit from this regimen.

PATIENTS AND METHODS

Patients received docetaxel 36 mg/m(2) i.v. on days 1, 8, and 15 and capecitabine orally 625 mg/m(2) b.i.d. from days 8 to 21. Cycles were repeated every 4 weeks. In the correlative study, we evaluated the TP expression by immunohistochemistry and the TP messenger RNA expression by real-time RT-PCR in the primary tumor.

RESULTS

Forty-seven women were enrolled. In the intention-to-treat analysis, objective responses were achieved in 24 patients (51%). Fourteen additional patients (30%) had stable disease. The median time to progression (TTP) was 6 months (range 1-44 months). Median survival was 17 months (range 1-48 months). Overall, the treatment was well tolerated. The most common clinical adverse events (all grades) were alopecia (55%), nail changes (53%), fatigue/asthenia (51%), nausea/vomiting (51%), neutropenia (49%), and neuropathy (49%). A significantly higher TTP was observed in patients with TP-positive tumors (log-rank test, P = 0.009). Interestingly, a subgroup analysis confirmed this TTP benefit in patients with TP-positive tumors obtaining a tumor response (log-rank test, P = 0.03), whereas the statistical significance was lost in nonresponders (log-rank test, P = 0.3).

CONCLUSIONS

This study indicates that a regimen with low doses of capecitabine plus weekly docetaxel is active against MBC. The correlative analysis provides preliminary evidence that TP expression may be a predictive marker for therapeutic benefit.