Capecitabine/Taxane Combination Therapy: Evolving Clinical Utility in Breast Cancer

KSP siRNA/paclitaxel-loaded PEGylated cationic liposomes for overcoming resistance to KSP inhibitors: Synergistic antitumor effects in drug-resistant ovarian cancer

Despite the promising anticancer effects of kinesin spindle protein (KSP) inhibition, functional plasticity of kinesins induced resistance against KSP inhibitors in a variety of cancers, leading to clinical failure. Additionally, paclitaxel is a widely used anticancer agent, but drug resistance has limited its use in the recurrent cancers. To overcome resistance against KSP inhibitors, we paired KSP inhibition with microtubule stabilization using KSP siRNA and paclitaxel. To enable temporal co-localization of both drugs in tumor cells in vivo, we exploited PEGylated cationic liposomes carrying both simultaneously. Drug synergism study shows that resistance against KSP inhibition can be suppressed by the action of microtubule-stabilizing paclitaxel, because microtubule stabilization prevents a different kinesin Kif15 from replacing all essential functions of KSP when KSP is inhibited. Our combination therapy showed more effective antiproliferative activity in vitro and in vivo than either paclitaxel or KSP siRNA alone. Ultimately, we could observe significantly improved therapeutic effects in the drug-resistant in vivo models, including cell line and patient-derived xenografts. Taken together, our combination therapy provides a potential anticancer strategy to overcome resistance against KSP inhibitors. Particularly, this strategy also provides an efficient approach to improve the therapeutic effects of paclitaxel in the drug-resistant cancers.

Genotypes of CYP2C8 and FGD4 and their association with peripheral neuropathy or early dose reduction in paclitaxel-treated breast cancer patients

Background:

The purpose of this study was to evaluate single-nucleotide polymorphisms (SNPs) in genes encoding key metabolising enzymes or involved in pharmacodynamics for possible associations with paclitaxel-induced peripheral neuropathy.

Methods:

The study population consists of 188 women from the multicenter, randomised, phase II ATX trial (BOOG2006-06; EudraCT number 2006-006058-83) that received paclitaxel and bevacizumab without or with capecitabine as first-line palliative therapy of HER2-negative metastatic breast cancer. Genotyping of CYP2C8*3 (c.416G>A), CYP3A4*22 (c.522-191C>T), TUBB2A (c.-101T>C), FGD4 (c.2044-236G>A) and EPHA5 (c.2895G>A) was performed by real-time PCR. Toxicity endpoints were cumulative dose (1) until first onset of grade ⩾1 peripheral neuropathy and (2) until first paclitaxel dose reduction from related toxicity (NCI-CTCAE version 3.0). SNPs were evaluated using the Kaplan–Meier method, the Gehan–Breslow–Wilcoxon test and the multivariate Cox regression analysis.

Results:

The rate of grade ⩾1 peripheral neuropathy was 67% (n=126). The rate of dose reduction was 46% (n=87). Age ⩾65 years was a risk factor for peripheral neuropathy (HR=1.87, P<0.008), but not for dose reduction. When adjusted for age, body surface area and total cumulative paclitaxel dose, CYP2C8*3 carriers had an increased risk of peripheral neuropathy (HR=1.59, P=0.045). FGD4 c.2044-236 A-allele carriers had an increased risk of paclitaxel dose reduction (HR per A-allele=1.38, P=0.036) when adjusted for total cumulative paclitaxel dose.

Conclusions:

These findings may point towards clinically useful indicators of early toxicity, but warrant further investigation.

Taxane modulation of anesthetic sensitivity in surgery for nonmetastatic breast cancer

STUDY OBJECTIVE AND DESIGN

The mechanism of action of commonly used general anesthetics is largely unknown. One hypothesized mechanism is through modulation of microtubule stability. Taxanes, a subset of chemotherapeutic drugs known to alter microtubule stability and commonly used to treat breast cancer, offer a natural experiment to test our hypothesis that patients exposed to taxanes prior to surgery, as compared to after surgery, would have a partial resistance to general anesthetics.

SETTING, PATIENTS, AND MEASUREMENTS

The anesthetic record of adult women with nonmetastatic breast cancer was used to obtain changes in heart rate and blood pressure surrounding incision, and the amount of inhaled anesthetic agent, induction, and rescue drugs administered.

MAIN RESULTS

Change in blood pressure in response to incision was significantly higher in the neoadjuvant group (P = .03), whereas change in heart rate was not (P = .53). A greater amount of morphine was administered in the neoadjuvant group (26.3 vs 15.5 mg, P = .02), although not a higher concentration of inhaled anesthetics (P = .15).

CONCLUSION

These results suggest that the alteration of microtubule stability is one of a number of mechanisms of inhaled anesthetics.

A phase II study of capecitabine plus docetaxel in gemcitabine-pretreated metastatic pancreatic cancer patients: CapTere

PURPOSE

Docetaxel and capecitabine combination is synergistic in preclinical models. We investigated the efficacy and toxicity of this combination as second-line chemotherapy in patients with metastatic pancreatic adenocarcinoma (mPC), pretreated with gemcitabine-based chemotherapy.

METHODS

Eligible patients were treated with capecitabine 800 mg/m(2) orally PO bid on days 1-14 in combination with intravenous docetaxel 30 mg/m(2) on days 1 and 8 of each 21-day cycle. The primary end point was overall response rate. Using a three-stage sequential design, two interim analyses for early stopping due to lack of efficacy were planned and conducted after 13 and 26 patients were accrued. Secondary end points included time to treatment failure, progression-free survival (PFS), overall survival (OS) and 50 % drop in CA19-9 levels.

RESULTS

Forty-three patients were evaluable for toxicity and 42 evaluable for response, at a median age of 64 years. The majority of patients (74 %) had ECOG PS 0-1. Six patients (14 %) achieved a partial tumor response, and stable disease for ≥2 cycles was observed in 59 % of patients (n = 25). Thirty-five percent (n = 11/31) of patients had a ≥50 % decrease in CA19-9 levels. The median PFS was 3.7 months (95 % CI 2.1-4.3 months), and the median OS was 5.3 months (95 % CI 4.3-8.6 months). Treatment was generally well tolerated. Grade 3 toxicity and grade 4 toxicity were seen in 45 and 5 % of patients, respectively. One patient had a potential treatment-related mortality.

CONCLUSIONS

The combination of capecitabine and docetaxel is active and well tolerated in mPC patients pretreated with gemcitabine-based therapy.

Neo-adjuvant capecitabine chemotherapy in women with newly diagnosed locally advanced breast cancer in a resource-poor setting (Nigeria): efficacy and safety in a phase II feasibility study

The majority of clinical trials of neo-adjuvant therapy for breast cancer have been conducted in resource-rich countries. We chose Nigeria, a resource-poor country, as the major site for a phase II feasibility open-label multicenter clinical trial designed to evaluate the efficacy, safety, and tolerability of neo-adjuvant capecitabine in locally advanced breast cancer (LABC). Planned treatment consisted of 24 weeks of capecitabine at a dose of 1,000 mg/m(2) twice daily (2,000 mg/m(2) total per day). The primary endpoints were overall, partial, complete clinical response rate (OCR, PCR, CCR) and complete pathologic response (cPR). A total of 16 patients were recruited from August 2007 to April 2010. The study was terminated early as a result of slow accrual. After the first three cycles of therapy, PCR were seen in five of 16 patients (31%; 95% CI 11-59%). Of the remaining 11 patients, eight had no response (NR) or stable disease (SD), and three had progressive disease (PD). Seven patients proceeded with further therapy of which had SD. OCR at the end of eight cycles was 44% (95% CI 20-70%). Clinical response and radiologic response by ultrasonomammography were highly concordant (spearman correlation 0.70). The most common adverse effect was Grade 1 hand-foot syndrome, which was seen in 75% of patients. Despite several limitations, we successfully carried out this phase II feasibility study of neo-adjuvant capecitabine for LABC in Nigeria. Capecitabine monotherapy showed good overall response rates with minimal toxicity and further studies are warranted.

A three-arm randomized phase II study of oral vinorelbine plus capecitabine versus oral vinorelbine and capecitabine in sequence versus docetaxel plus capecitabine in patients with metastatic breast cancer previously treated with anthracyclines

Owing to the increased number of patients treated with anthracycline-based adjuvant chemotherapy, there is a need for new effective and tolerable nonanthracycline regimens in metastatic breast cancer. Patients with HER2-negative metastatic breast cancer previously treated with anthracyclines in (neo)adjuvant setting were randomized to fully oral 3 weekly cycles of the combination of oral vinorelbine with capecitabine (V + C), to the same drugs alternating every three cycles (V↔C), or to the combination of docetaxel and capecitabine (D + C). V was given at 80 mg/m(2) (after the first cycle at 60 mg/m(2)) on days 1 and 8 in the V + C arm and weekly in the V↔C arm, C at 1,000 mg/m(2) bid from days 1 to 14, and D on day 1 at 75 mg/m(2). The primary end point was disease control rate (CR + PR + NC ≥ 3 months). A total of 139 patients were randomly assigned to V + C (44 patients), V↔C (47 patients), and D + C (48 patients). After an independent review, the disease control rate in the intent-to-treat population in the V + C, V↔C, and D + C arms [95% CI] was 70.5% [54.8-83.2], 37.0% [23.2-52.5], and 70.8% [55.9-83.1], and the median overall survival 22.2, 19.4, and 24.2 months, respectively. When taken into account the disease control rate, the alternating V↔C regimen seems to be less effective compared with V + C or D + C combinations. Combinations of V + C or D + C showed similar efficacy and a different toxicity profile; V + C induced less neutropenia, infection, hand-foot syndrome, fatigue/asthenia, and alopecia, whereas D + C - less gastrointestinal toxicity. V + C combination constitutes a valuable fully oral alternative option to D + C in patients with metastatic breast cancer previously treated with anthracyclines in (neo)adjuvant setting, while offering the advantages of an all-oral treatment.

Phase II trial of paclitaxel and uracil--tegafur in metastatic breast cancer. TEGATAX trial

This Phase II trial investigated the combination paclitaxel (P) and uracil-tegafur (UFT) in patients with metastatic breast cancer (MBC).

METHODS

Main eligibility criteria included HER-2 negative MBC, ECOG performance status of 0-2, exposure to 1-2 prior chemotherapy regimen in the metastatic setting, previous exposure to an anthracycline containing regimen either at metastatic or adjuvant setting. Each 35-day cycle consisted of P at 80 mg/m(2) by intravenous infusion on days 1, 8, 15, 22 and 29 and oral UFT at 300 mg/m(2) TID (three time a day) from days 1-28 and oral folinic acid at 90 mg QD (one a day).

RESULTS

Between March 2003 and December 2007, 31 patients were enrolled. Median age was 66 years (range 44-78). All tumours were HER-2 negative and 7% were triple negative (ER, PgR, HER-2). The majority of patients had visceral disease (81%). All patients had received an anthracycline containing regimen and 74% had a previous docetaxel containing treatment. Median of 4 and 3 cycles of P and UFT were administered with a relative dose intensity of 85.3% and 94.3%, respectively. Twelve (40%)(95% CI: 22.5-57.5) confirmed ORR were observed. Stable and progression disease were reported in 43% and 17% of cases. Median Response duration was 8.4 month (95% CI: 4.9-11.7), median Time to progression was 9.5 months (95% CI: 6.6-13.8) and median Overall Survival was 23.5 months (95% CI: 16.8-37.2). Thirteen pts (43%) experienced a grade 3 or 4 adverse events (AEs): One death occurred related to the study drugs (febrile neutropenia). Chemotherapy was discontinued due to toxicity in 30% of pts

CONCLUSIONS

Accrual was closed in January 2008 due to concerns regarding the degree and accumulative nature of AEs. Nonetheless, the ORR is encouraging and warranted further studies with adapted doses and schedules.

The relevance of breast cancer subtypes in the outcome of neoadjuvant chemotherapy

Background

Breast cancer is increasingly considered a heterogeneous disease. The aim of this study was to assess the differences between histological and receptor-based subtypes in breast-conserving surgery and pathological complete response (pCR) after neoadjuvant chemotherapy.

Method

A consecutive series of 254 patients with operable breast cancer treated with neoadjuvant chemotherapy was analyzed. Tumors were classified according to their receptor status in estrogen receptor (ER)-positive tumors (HER2-negative), triple-negative tumors, and HER2-positive tumors. The type of surgery feasible prior to neoadjuvant chemotherapy was compared with the actual surgery performed.

Results

The overall increase in breast-conserving surgery was 37% (73 of 198). In patients with ductal and lobular carcinomas this increase was 41% (63 of 152, 95% confidence interval [95% CI] 0.34–0.49) and 20% (7 of 35, 95% CI 0.10–0.36), respectively (P = 0.02). Half of the patients with lobular carcinoma had to undergo a secondary mastectomy because of incomplete resection margins. In ER-positive, triple-negative and HER2-positive tumors, the increase in breast-conserving surgery was 39% (42 of 109, 95% CI 0.30–0.48), 24% (11 of 45, 95% CI 0.14–0.38), and 45% (20 of 44, 95% CI 0.32–0.60) (P = 0.11). The pCR rate in ductal and lobular carcinomas was 12% (23 of 195) and 2% (1 of 42), respectively (P = 0.09). In ER-positive, triple-negative and HER2-positive tumors the pCR rates were 2% (3 of 138), 28% (16 of 57), and 18% (10 of 56), respectively. Multivariate analysis showed that the receptor-based subtype was the only significant predictor of pCR (P = 0.004).

Conclusion

In lobular tumors the benefit with regard to breast-conserving surgery of neoadjuvant chemotherapy is questionable. Although in ER-positive tumors the pCR rate is low, the increase in breast-conserving surgery was remarkable in ductal ER-positive tumors.

The 70-gene signature as a response predictor for neoadjuvant chemotherapy in breast cancer

The 70-gene signature (MammaPrint) is a prognostic tool used to guide adjuvant treatment decisions. The aim of this study was to assess its value to predict chemosensitivity in the neoadjuvant setting. We obtained the 70-gene profile of stage II-III patients prior to neoadjuvant chemotherapy and classified the prognosis-signatures. Pathological complete remission (pCR) was used to measure chemosensitivity. Among 167 patients, 144 (86%) were having a poor and 23 (14%) a good prognosis-signature. None of the good prognosis-signature patients achieved a pCR (0/23), whereas 29/144 patients (20%) in the poor prognosis-signature group did (P = 0.015). All triple-negative tumors (n = 38) had a poor prognosis-signature. Within the non triple-negative subgroup, the response of the primary tumor remained associated with the classification of the prognosis-signature (P = 0.023). A pCR is unlikely to be achieved in tumors that have a good prognosis-signature. Tumors with a poor prognosis-signature are more sensitive to chemotherapy.

The novel combination of chlorpromazine and pentamidine exerts synergistic antiproliferative effects through dual mitotic action

Combination therapy has proven successful in treating a wide variety of aggressive human cancers. Historically, combination treatments have been discovered through serendipity or lengthy trials using known anticancer agents with similar indications. We have used combination high-throughput screening to discover the unexpected synergistic combination of an antiparasitic agent, pentamidine, and a phenothiazine antipsychotic, chlorpromazine. This combination, CRx-026, inhibits the growth of tumor cell lines in vivo more effectively than either pentamidine or chlorpromazine alone. Here, we report that CRx-026 exerts its antiproliferative effect through synergistic dual mitotic action. Chlorpromazine is a potent and specific inhibitor of the mitotic kinesin KSP/Eg5 and inhibits tumor cell proliferation through mitotic arrest and accumulation of monopolar spindles. Pentamidine treatment results in chromosomal segregation defects and delayed progression through mitosis, consistent with inhibition of the phosphatase of regenerating liver family of phosphatases. We also show that CRx-026 synergizes in vitro and in vivo with the microtubule-binding agents paclitaxel and vinorelbine. These data support a model where dual action of pentamidine and chlorpromazine in mitosis results in synergistic antitumor effects and show the importance of systematic screening for combinations of targeted agents.