An EORTC phase I study of capecitabine (Xeloda) in combination with fixed doses of cyclophosphamide and epirubicin (cex) as primary treatment for large operable or locally advanced/inflammatory breast cancer.

In breast cancer, chemotherapy regimens that include infusional 5-fluorouracil (5-FU) lead to high response rates, but require central venous access and pumps. To avoid these inconveniences, we substituted infusional 5-FU with capecitabine. The main objective of this study was to determine the maximum tolerated dose (MTD) of capecitabine when given in combination with fixed doses of epirubicin and cyclophosphamide (100 and 600 mg/m(2) day 1 every (q) 3 weeks) as primary treatment for large operable or locally advanced/inflammatory breast cancer without distant metastasis. Capecitabine was escalated from 750 mg/m(2) twice a day (bid) to 1250 mg/m(2) bid from day 1 to day 14 in four dose levels. Dose escalation was permitted if 0/3 or 1/6 patients experienced dose-limiting toxicity (DLT). A total of 23 patients were included and 117 courses were administered. At dose level 4, 2 of 2 patients presented DLTs defining the MTD. A high rate of capecitabine treatment modification was required with capecitabine 1050 mg/m(2) bid (dose level 3). 19 patients achieved an objective response (83%). In conclusion, we believe that capecitabine 900 mg/m(2) bid (dose level 2) is the recommended dose in combination with epirubicin 100 mg/m(2) and cyclophosphamide 600 mg/m(2). The acceptable toxicity profile and encouraging activity of this regimen warrant further evaluation.

An EORTC phase I study of epirubicin in combination with fixed doses of cyclophosphamide and infusional 5-fu (CEF-infu) as primary treatment of large operable or locally advanced/inflammatory breast cancer.

PURPOSE: The association of continuous infusion 5-fluorouracil, epirubicin (50 mg/m2 q 3 weeks) and a platinum compound (cisplatin or carboplatin) was found to be very active in patients with either locally advanced/inflammatory (LA/I) [1, 2] or large operable (LO) breast cancer (BC) [3]. The same rate of activity in terms of response rate (RR) and response duration was observed in LA/I BC patients when cisplatin was replaced by cyclophosphamide [4]. The dose of epirubicin was either 50 mg/m2 [ 1, 2, 3] or 60 mg/m2/cycle [4]. The main objective of this study was to determine the maximum tolerated dose (MTD) of epirubicin when given in combination with fixed doses of cyclophosphamide and infusional 5-fluorouracil (CEF-infu) as neoadjuvant therapy in patients with LO or LA/I BC for a maximum of 6 cycles. PATIENTS AND METHODS: Eligible patients had LO or LA/I BC, a performance status 0-1, adequate organ function and were <65 years old. Cyclophosphamide was administered at the dose of 400 mg/m2 day 1 and 8, q 4 weeks and infusional 5-fluorouracil 200 mg/m2/day was given day 1-28, q 4 weeks. Epirubicin was escalated from 30 to 45 and to 60 mg/m2 day 1 and 8; dose escalation was permitted if 0/3 or 1/6 patients experienced dose limiting toxicity (DLT) during the first 2 cycles of therapy. DLT for epirubicin was defined as febrile neutropenia, grade 4 neutropenia lasting for >7 days, grade 4 thrombocytopenia, or any non-haematological toxicity of CTC grade > or =3, excluding alopecia and plantar-palmar erythrodysesthesia (this toxicity was attributable to infusional 5-fluorouracil and was not considered a DLT of epirubicin). RESULTS: A total of 21 patients, median age 44 years (range 29-63) have been treated. 107 courses have been delivered, with a median number of 5 cycles per patient (range 4-6). DLTs on cycles I and 2 on level 1, 2, 3: grade 3 (G3) mucositis occurred in 1/10 patients treated at the third dose level. An interim analysis showed that G3 PPE occurred in 5/16 pts treated with the 28-day infusional 5-FU schedule at the 3 dose levels. The protocol was subsequently amended to limit the duration of infusional 5-fluorouracil infusion from 4 to 3 weeks. No G3 PPE was detected in 5 patients treated with this new schedule. CONCLUSIONS: This study establishes that epirubicin 60mg/m2 day 1 and 8, cyclophosphamide 400mg/m2 day 1 and 8 and infusional 5-fluorouracil 200 mg/m2/day day 1-21. q 4 weeks is the recommended dose level. Given the encouraging activity of this regimen (15/21 clinical responses) we have replaced infusional 5-fluorouracil by oral capecitabine in a recently activated study.

A feasibility study evaluating docetaxel-based sequential and combination regimens in the adjuvant therapy of node-positive breast cancer

BACKGROUND AND PURPOSE: Docetaxel is an active agent in the treatment of metastatic breast cancer. We evaluated the feasibility of docetaxel-based sequential and combination regimens as adjuvant therapies for patients with node-positive breast cancer. PATIENTS AND METHODS: Three consecutive groups of patients with node-positive breast cancer or locally-advanced disease, aged < or = 70 years, received one of the following regimens: a) sequential A-->T-->CMF: doxorubicin 75 mg/m2 q 3 weeks x 3, followed by docetaxel 100 mg/m2 q 3 weeks x 3, followed by i.v. CMF days 1 + 8 q 4 weeks x 3; b) sequential accelerated A-->T-->CMF: A and T were administered at the same doses q 2 weeks; c) combination therapy: doxorubicin 50 mg/m2 + docetaxel 75 mg/m2 q 3 weeks x 4, followed by CMF x 4. When indicated, radiotherapy was administered during or after CMF, and tamoxifen started after the end of CMF. RESULTS: Seventy-nine patients have been treated. Median age was 48 years. A 30% rate of early treatment discontinuation was observed in patients receiving the sequential accelerated therapy (23% during A-->T), due principally to severe skin toxicity. Median relative dose-intensity was 100% in the three treatment arms. The incidence of G3-G4 major toxicities by treated patients, was as follows: skin toxicity a: 5%; b: 27%; c: 0%; stomatitis a: 20%; b: 20%; c: 3%. The incidence of neutropenic fever was a: 30%; b: 13%; c: 48%. After a median follow-up of 18 months, no late toxicity has been reported. CONCLUSIONS: The accelerated sequential A-->T-->CMF treatment is not feasible due to an excess of skin toxicity. The sequential non accelerated and the combination regimens are feasible and under evaluation in a phase III trial of adjuvant therapy.

3-year results of docetaxel-based sequential and combination regimens in the adjuvant therapy of node-positive breast cancer: a pilot study.

BACKGROUND: Docetaxel has proven efficacy in metastatic breast cancer. In this pilot study, we explored the efficacy/feasibility of docetaxel-based sequential and combination regimens as adjuvant therapy of node-positive breast cancer. PATIENTS AND METHODS: From March 1996 till March 1998, four consecutive groups of patients with stages II and III breast cancer, aged < or = 70 years, received one of the following regimens: a) sequential Doxorubicin (A) --> Docetaxel (T) --> CMF (Cyclophosphamide+Methotrexate+5-Fluorouracil): A 75 mg/m q 3 wks x 3, followed by T100 mg/m2 q 3 wks x 3, followed by i.v. CMF Days 1+8 q 4 wks x 3; b) sequential accelerated A --> T --> CMF: A and T administered at the same doses q 2 wks with Lenograstin support; c) combination therapy: A 50 mg/m2 + T 75 mg/m2 q 3 wks x 4, followed by CMF x 4; d) sequential T --> A --> CMF: T and A, administered as in group a), with the reverse sequence. When indicated, radiotherapy was administered during or after CMF, and Tamoxifen after CMF. RESULTS: Ninety-three patients were treated. The median age was 48 years (29-66) and the median number of positive axillary nodes was 6 (1-25). Tumors were operable in 94% and locally advanced in 6% of cases. Pathological tumor size was >2 cm in 72% of cases. There were 21 relapses, (18 systemic, 3 locoregional) and 11 patients (12%) have died from disease progression. At median follow-up of 39 months (6-57), overall survival (OS) was 87% (95% CI, 79-94%) and disease-free survival (DFS) was 76% (95% CI, 67%-85%). CONCLUSION: The efficacy of these docetaxel-based regimens, in terms of OS and DFS, appears to be at least as good as standard anthracycline-based adjuvant chemotherapy (CT), in similar high-risk patient populations.

Taxanes alone or in combination with anthracyclines as first-line therapy of patients with metastatic breast cancer.

PURPOSE: Taxanes (paclitaxel or docetaxel) have been sequenced or combined with anthracyclines (doxorubicin or epirubicin) for the first-line treatment of advanced breast cancer. This meta-analysis uses data from all relevant trials to detect any advantages of taxanes in terms of tumor response, progression-free survival (PFS), and survival. PATIENTS AND METHODS: Individual patient data were collected on eight randomized combination trials comparing anthracyclines + taxanes (+ cyclophosphamide in one trial) with anthracyclines + cyclophosphamide (+ fluorouracil in four trials), and on three single-agent trials comparing taxanes with anthracyclines. Combination trials included 3,034 patients; single-agent trials included 919 patients. RESULTS: Median follow-up of living patients was 43 months, median survival was 19.3 months, and median PFS was 7.1 months. In single-agent trials, response rates were similar in the taxanes (38%) and in the anthracyclines (33%) arms (P = .08). The hazard ratios for taxanes compared with anthracyclines were 1.19 (95% CI, 1.04 to 1.36; P = .011) for PFS and 1.01 (95% CI, 0.88 to 1.16; P = .90) for survival. In combination trials, response rates were 57% (10% complete) in taxane-based combinations and 46% (6% complete) in control arms (P < .001). The hazard ratios for taxane-based combinations compared with control arms were 0.92 (95% CI, 0.85 to 0.99; P = .031) for PFS and 0.95 (95% CI, 0.88 to 1.03; P = .24) for survival. CONCLUSION: Taxanes were significantly worse than single-agent anthracyclines in terms of PFS, but not in terms of response rates or survival. Taxane-based combinations were significantly better than anthracycline-based combinations in terms of response rates and PFS, but not in terms of survival.

Early versus delayed fixed dose combination abacavir/lamivudine/zidovudine in patients with HIV and tuberculosis in Tanzania.

Fixed dose combination abacavir/lamivudine/zidovudine (ABC/3TC/ZDV) among HIV-1 and tuberculosis (TB)-coinfected patients was evaluated and outcomes between early vs. delayed initiation were compared. In a randomized, pilot study conducted in the Kilimanjaro Region of Tanzania, HIV-infected inpatients with smear-positive TB and total lymphocyte count <1200/mm(3) were randomized to initiate ABC/3TC/ZDV either 2 (early) or 8 (delayed) weeks after commencing antituberculosis therapy and were followed for 104 weeks. Of 94 patients screened, 70 enrolled (41% female, median CD4 count 103 cells/mm(3)), and 33 in each group completed 104 weeks. Two deaths and 12 serious adverse events (SAEs) were observed in the early arm vs. one death, one clinical failure, and seven SAEs in the delayed arm (p = 0.6012 for time to first grade 3/4 event, SAE, or death). CD4 cell increases were +331 and +328 cells/mm(3), respectively. TB-immune reconstitution inflammatory syndromes (TB-IRIS) were not observed in any subject. Using intent-to-treat (ITT), missing = failure analyses, 74% (26/35) vs. 89% (31/35) randomized to early vs. delayed therapy had HIV RNA levels <400 copies/ml at 104 weeks (p = 0.2182) and 66% (23/35) vs. 74% (26/35), respectively, had HIV RNA levels <50 copies/ml (p = 0.6026). In an analysis in which switches from ABC/3TC/ZDV = failure, those receiving early therapy were less likely to be suppressed to <400 copies/ml [60% (21/35) vs. 86% (30/35), p = 0.030]. TB-IRIS was not observed among the 70 coinfected subjects beginning antiretroviral treatment. ABC/3TC/ZDV was well tolerated and resulted in steady immunologic improvement. Rates of virologic suppression were similar between early and delayed treatment strategies with triple nucleoside regimens when substitutions were allowed.

Doxifluridine and leucovorin: an oral treatment combination in advanced colorectal cancer

Purpose: This study was designed to test the activity and feasibility of an all-oral regimen of levo-leucovorin and doxifluridine (dFUR) in the treatment of advanced colorectal cancer and to establish whether the pharmacokinetics of dFUR and fluorouracil (FU) are affected by demographic and/or biologic parameters. Materials and Methods: One hundred eight patients with histologically proven colorectal cancer received orally administered levo-leucovorin 25 mg followed 2 hours later by dFUR 1,200 mg/m2 on days 1 to 5, with the cycle being repeated every 10 days. Results: Among 62 previously untreated patients, two complete responses (CRs) and 18 partial responses (PRs) were observed (overall response rate, 32%; 95% confidence interval, 21% to 45%). The median response duration was 4 months (range, 2 to 13) and the median survival time, 14 months. Among 46 pretreated patients, there were three CRs and three PRs (response rate, 13%; 95% confidence interval, 5% to 26%). In this group of patients, the median response duration was 4 months (range, 1 to 12) and the median survival time, 12 months. No toxic deaths were observed. The only World Health Organization (WHO) grade 3 to 4 side effect was diarrhea (32 patients). Conclusion: This regimen is active in previously untreated colorectal cancer patients and combines good compliance with safety. Limited but definite efficacy was also detected in the patients previously treated with FU, which suggests incomplete cross- resistance between the two drugs. The pharmacokinetic results suggest that the conversion rate of dFUR to FU increases between days 1 and 5, but that FU levels remain low in comparison to those measured after classical FU therapy. Under the experimental conditions used in this study, the interpatient variability of pharmacokinetic parameters remains largely unexplained by the tested variables.

Multicenter randomized trial of dacarbazine alone or in combination with two different doses and schedules of interferon alfa-2a in the treatment of advanced melanoma

Purpose: Some phase II studies have suggested that the combination of interferons (IFNs) with dacarbazine (DTIC) in the treatment of malignant melanoma (MM) increases the antitumor activity of DTIC alone. In an attempt to confirm this hypothesis, a randomized study was performed with the further intent of observing whether low doses of recombinant interferon alfa-2a (rIFNα2a) could be as effective as intermediate doses. Patients and Methods: Two hundred sixty-six patients were randomized onto three different treatment arms: DTIC 800 mg/m 2 intravenously (IV) days 1 and 21; DTIC plus rIFNα2a 9 mIU intramuscularly (IM) daily; and DTIC plus rIFNα2a 3 mIU IM three times per week. Major prognostic factors were well balanced among the three arms. Chemotherapy was administered for a maximum of eight cycles. After 6 months of therapy, rIFNα2a was continued until disease progression at 3 mIU three times per week in responding patients who had received the combined treatment. Results: The percentage of objective responses did not differ among the three groups (20%, 28%, and 23%, respectively), although a significant prolongation of response duration was observed when rIFNα2a was added to DTIC (2.6 v 8.4 v 5.5 months, respectively). However, this improvement in response duration did not translate into an amelioration of overall survival. The addition of rIFNα2a led to the onset of flu-like syndrome, but in no case was it necessary to withdraw the treatment program and no toxic deaths or life-threatening toxicities were reported. Conclusion: In this study, rIFNα2a significantly prolonged response duration, whereas no effects on response rate and survival were observed; rIFNα2a 3 mIU appeared to be equally effective and better tolerated than 9 mIU.

A phase I study of the p-glycoprotein antagonist Tarquidar in combination with Vinorelbine.

P-glycoprotein (Pgp) antagonists have had unpredictable pharmacokinetic interactions requiring reductions of chemotherapy. We report a phase I study using tariquidar (XR9576), a potent Pgp antagonist, in combination with vinorelbine. EXPERIMENTAL DESIGN: Patients first received tariquidar alone to assess effects on the accumulation of (99m)Tc-sestamibi in tumor and normal organs and rhodamine efflux from CD56+ mononuclear cells. In the first cycle, vinorelbine pharmacokinetics was monitored after the day 1 and 8 doses without or with tariquidar. In subsequent cycles, vinorelbine was administered with tariquidar. Tariquidar pharmacokinetics was studied alone and with vinorelbine. RESULTS: Twenty-six patients were enrolled. Vinorelbine 20 mg/m(2) on day 1 and 8 was identified as the maximum tolerated dose (neutropenia). Nonhematologic grade 3/4 toxicities in 77 cycles included the following: abdominal pain (4 cycles), anorexia (2), constipation (2), fatigue (3), myalgia (2), pain (4) and dehydration, depression, diarrhea, ileus, nausea, and vomiting, (all once). A 150-mg dose of tariquidar: (1) reduced liver (99m)Tc-sestamibi clearance consistent with inhibition of liver Pgp; (2) increased (99m)Tc-sestamibi retention in a majority of tumor masses visible by (99m)Tc-sestamibi; and (3) blocked Pgp-mediated rhodamine efflux from CD56+ cells over the 48 hours examined. Tariquidar had no effects on vinorelbine pharmacokinetics. Vinorelbine had no effect on tariquidar pharmacokinetics. One patient with breast cancer had a minor response, and one with renal carcinoma had a partial remission. CONCLUSIONS: Tariquidar is a potent Pgp antagonist, without significant side effects and much less pharmacokinetic interaction than previous Pgp antagonists. Tariquidar offers the potential to increase drug exposure in drug-resistant cancers.

Multisubstrate adduct inhibitors: Drug design and biological tools

In drug discovery, different methods exist to create new inhibitors possessing satisfactory biological activity. The multisubstrate adduct inhibitor (MAI) approach is one of these methods, which consists of a covalent combination between analogs of the substrate and the cofactor or of the multiple substrates used by the target enzyme. Adopted as the first line of investigation for many enzymes, this method has brought insights into the enzymatic mechanism, structure, and inhibitory requirements. In this review, the MAI approach, applied to different classes of enzyme, is reported from the point of view of biological activity.

Understanding the Performance of Melt-Extruded Poly(ethylene oxide)–Bicalutamide Solid Dispersions: Characterisation of Microstructural Properties Using Thermal, Spectroscopic and Drug Release Methods

In this article, we have prepared hot-melt-extruded solid dispersions of bicalutamide (BL) using poly(ethylene oxide) (PEO) as a matrix platform. Prior to preparation, miscibility of PEO and BL was assessed using differential scanning calorimetry (DSC). The onset of BL melting was signi?cantly depressed in the presence of PEO, and using Flory– Huggins (FH) theory, we identi?ed a negative value of -3.4, con?rming miscibility. Additionally, using FH lattice theory, we estimated the Gibbs free energy of mixing which was shown to be negative, passing through a minimum at a polymer fraction of 0.55. Using these data, solid dispersions at drug-to-polymer ratios of 1:10, 2:10 and 3:10 were prepared via hot-melt extrusion. Using a combination of DSC, powder X-ray diffractometry and scanning electron
microscopy, amorphous dispersions of BL were con?rmed at the lower two drug loadings. At the 3:10 BL to PEO ratio, crystalline BL was detected. The percent crystallinity of PEO was reduced by approximately 10% in all formulations following extrusion. The increased amorphous content within PEO following extrusion accommodated amorphous BL at drug to polymer loadings up to 2:10; however, the increased amorphous domains with PEO following extrusion were not suf?cient to fully accommodate BL at drug-to-polymer ratios of 3:10.

Microneedle-Iontophoresis Combinations for Enhanced Transdermal Drug Delivery

It has recently been proposed that the combination of skin barrier impairment using microneedles (MNs) coupled with iontophoresis (ITP) may broaden the range of drugs suitable for transdermal delivery as well as enabling the rate of delivery to be achieved with precise electronic control. However, few reports exist on the combination of ITP with in situ drug-loaded polymeric MN delivery systems. Our in vitro permeation studies revealed that MN enhances transdermal drug delivery. The combination of dissolving MN and ITP did not further enhance the extent of delivery of the low molecular weight drug ibuprofen sodium after short application periods. However, the extent of peptide/protein delivery was significantly enhanced when ITP was used in combination with hydrogel-forming MN arrays. As such, hydrogel-forming MN arrays show promise for the electrically controlled transdermal delivery of biomacromolecules in a simple, one-step approach, though further technical developments will be necessary before patient benefit is realized.

Synergistic effects of proteasome inhibitor carfilzomib in combination with tyrosine kinase inhibitors in imatinib-sensitive and -resistant chronic myeloid leukemia models

The tyrosine kinase inhibitor (TKI) imatinib has transformed the treatment and outlook of chronic myeloid leukemia (CML); however, the development of drug resistance and the persistence of TKI-resistant stem cells remain obstacles to eradicating the disease. Inhibition of proteasome activity with bortezomib has been shown to effectively induce apoptosis in TKI-resistant cells. In this study, we show that exposure to the next generation proteasome inhibitor carfilzomib is associated with a decrease in ERK signaling and increased expression of Abelson interactor proteins 1 and 2 (ABI-1/2). We also investigate the effect of carfilzomib in models of imatinib-sensitive and -resistant CML and demonstrate a potent reduction in proliferation and induction of apoptosis in a variety of models of imatinib-resistant CML, including primitive CML stem cells. Carfilzomib acts synergistically with the TKIs imatinib and nilotinib, even in imatinib-resistant cell lines. In addition, we found that the presence of immunoproteasome subunits is associated with an increased sensitivity to carfilzomib. The present findings provide a rational basis to examine the potential of carfilzomib in combination with TKIs as a potential therapy for CML, particularly in imatinib-resistant disease.

Pre-clinical development of a combination microbicide vaginal ring containing dapivirine and darunavir

Objectives: Combination microbicide vaginal rings may be more effective than single microbicide rings at reducing/preventing sexual transmission of HIV. Here, we report the preclinical development and macaque pharmacokinetics of matrix-type silicone elastomer vaginal rings containing dapivirine and darunavir.

Methods: Macaque rings containing 25 mg dapivirine, 300 mg darunavir and 100 mg dapivirine, and 300 mg darunavir were manufactured and characterised by differential scanning calorimetry. In vitro release was assessed into isopropanol/water and simulated vaginal fluid. Macaque vaginal fluid and blood serum concentrations for both antiretrovirals were measured during 28-day ring use. Tissue levels were measured on day 28. Ex vivo challenge studies were performed on vaginal fluid samples and IC50 values calculated.

Results: Darunavir caused a concentration-dependent reduction in the dapivirine melting temperature in both solid drug mixes and in the combination ring. In vitro release from rings was dependent on drug loading, the number of drugs present, and the release medium. In macaques, serum concentrations of both microbicides were maintained between 101–102 pg/mL. Vaginal fluid levels ranged between 103–104 ng/g and 104–105 ng/g for dapivirine and darunavir, respectively. Tissue concentrations ranges for each drug were: vagina (1.8×103–3.8×103 ng/g) > cervix (9.4×101–3.9×102 ng/g) > uterus (0–108 ng/g) > rectum (0–40 ng/g). Measured IC50 values were > 2 ng/mL for both compounds.

Conclusions: Based on these results, and in light of recent clinical progress of the 25mg dapivirine ring, a combination vaginal ring containing dapivirine and darunavir is a viable second-generation HIV microbicide candidate.

Fibroblast growth factor receptor 4 (FGFR4): a targetable regulator of drug resistance in colorectal cancer

The discovery of underlying mechanisms of drug resistance, and the development of novel agents to target these pathways, is a priority for patients with advanced colorectal cancer (CRC). We previously undertook a systems biology approach to design a functional genomic screen and identified fibroblast growth factor receptor 4 (FGFR4) as a potential mediator of drug resistance. The aim of this study was to examine the role of FGFR4 in drug resistance using RNAi and the small-molecule inhibitor BGJ398 (Novartis). We found that FGFR4 is highly expressed at the RNA and protein levels in colon cancer tumour tissue compared with normal colonic mucosa and other tumours. Silencing of FGFR4 reduced cell viability in a panel of colon cancer cell lines and increased caspase-dependent apoptosis. A synergistic interaction was also observed between FGFR4 silencing and 5-fluorouracil (5-FU) and oxaliplatin chemotherapy in colon cancer cell lines. Mechanistically, FGFR4 silencing decreased activity of the pro-survival STAT3 transcription factor and expression of the anti-apoptotic protein c-FLIP. Furthermore, silencing of STAT3 resulted in downregulation of c-FLIP protein expression, suggesting that FGFR4 may regulate c-FLIP expression via STAT3. A similar phenotype and downstream pathway changes were observed following FGFR4 silencing in cell lines resistant to 5-FU, oxaliplatin and SN38 and upon exposure of parental cells to the FGFR small-molecule inhibitor BGJ398. Our results indicate that FGFR4 is a targetable regulator of chemo-resistance in CRC, and hence inhibiting FGFR4 in combination with 5-FU and oxaliplatin is a potential therapeutic strategy for this disease.