The implementation of venous leg ulcer guidelines: process analysis of the intervention used in a multi-centre, pragmatic, randomized, controlled trial

The production and implementation of clinical practice guidelines is currently a high political priority and a rapidly developing field within healthcare in the United Kingdom (UK). Their purpose is to provide clinicians with a synthesis of the best available external evidence and operationalize the implementation of evidence-based practice. Despite indications that clinical guidelines can make a difference to the quality of patient care, there is some evidence that practitioners struggle with their application. The aim of this paper is to report one element of a trial undertaken by three collaborating universities in the Northern and Yorkshire Region of the UK health service during 1997-1998. The objective was to understand what makes guidelines acceptable and usable, or otherwise, to health professionals. The findings reported in this paper describe the process of care in those general practices that elected to implement guidelines for the management of patients with venous leg ulcers. We conclude that planning for training, resource and quality improvement processes must be built into a team's guidelines implementation procedures. A preliminary needs analysis of the contextual 'hurdles and levers' within each primary healthcare team is also necessary to identify individual issues that must be addressed if the process is to succeed. These findings provide some lessons for successful implementation of clinical guidelines in general. Recommendations for nursing policy makers, managers, practitioners and researchers are included.

Phase I and pharmacokinetic study of two sequences of gemcitabine and docetaxel administered weekly to patients with advanced cancer

PURPOSE

To determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and effect of drug sequence on toxicities and pharmacokinetics of the combination of gemcitabine and docetaxel.

METHODS

A total of 34 patients with advanced cancers were treated with gemcitabine and docetaxel on days 1 and 8 of each 21-day cycle according to the following dose escalation schedule: level 1, 800 and 30 mg/m2, respectively; level 2, 800 and 40 mg/m2; level 3, 1,000 and 40 mg/m2; and level 4, 1,250 and 40 mg/m2. At each dose level, at least three patients were assigned to one of the two sequences of drug administration: gemcitabine-->docetaxel or docetaxel-->gemcitabine. Once the MTD had been reached, six additional patients, who had received no more than one chemotherapy regimen, were enrolled to dose levels 3 and 4 (gemcitabine-->docetaxel) to determine the MTD in minimally pretreated patients.

RESULTS

Neutropenia was the most frequent DLT with an overall incidence of 23.5%. Grade 3/4 neutropenia occurred in 62% of patients (8/13) who had received two or more prior chemotherapy regimens, but not at all (0/15) in patients who had received no more than one prior chemotherapy regimens (P< 0.001). Additional DLTs included grade 4 diarrhea and grade 4 stomatitis in one patient each. The MTD was determined to be gemcitabine 800 mg/m2 and docetaxel 40 mg/m2 in patients who had received two or more prior chemotherapy regimens. However, minimally pretreated patients (no more than one prior chemotherapy regimen) were able to tolerate higher doses with an MTD of gemcitabine 1,250 mg/m2 and docetaxel 40 mg/m2. There were no significant differences in toxicities or pharmacokinetics between the two sequences of administration. Partial and minor responses were observed in 23.5% of patients: non-small-cell lung (two of eight), gastric (two of three), head and neck (one of two), bladder (two of four) and hepatocellular cancer (one of one).

CONCLUSIONS

The combination of gemcitabine and docetaxel administered on days 1 and 8 every 21 days was feasible and well tolerated in patients with advanced malignancies. The sequence of administration had no significant effect on the toxicity or pharmacokinetics of either drug. Minimally pretreated patients tolerated higher doses of this combination without significant toxicities. This schedule and combination demonstrated activity in a variety of solid tumors, and merits further evaluation.

Detection of a mixed-backbone oligonucleotide (GEM 231) in liver and tumor tissues by capillary electrophoresis

A simple, rapid and sensitive method has been developed and validated for the analysis of a mixed-backbone oligonucleotide (GEM 231) in tumor tissues. The analysis was performed using a capillary electrophoresis (CE) system with UV detection. An extended light path (bubble cell) capillary column of 64.5 cm (effective length 56 cm) x 50 microm I.D. is used as the separation column. The optimized chromatographic conditions were background electrolyte: sodium borate buffer (60 mM, pH 9.1), electrokinetic injection: 10 s, applied voltage: 30 kV, detection at lambda = 210 nm. A linear relationship was observed between the peak area and the amount of GEM 231 in the range of 1.0-1000 microg/ml. The lower detection limit of the drug was 100 pg with an average recovery of about 75 +/- 5%. The inter-day and intra-day relative standard deviations were <10%. Assay validation studies revealed that CE method is reproducible and specific for the determination of GEM 231 in tissue homogenates with a run time of less than 5 min.

Capecitabine in colorectal cancer

Capecitabine (Xeloda) is the first orally available fluoropyrimidine approved for use in patients with cancer. It was initially approved for use in metastatic breast cancer, but significant data also support its use in the management of metastatic colorectal cancer. Capecitabine relies on a series of metabolic steps, the last of which occurs primarily within cancer cells. This results in selective activation of the compound within cancer cells, thereby reducing systemic toxicities and allowing for greater dose intensity. This article reviews selected phase I, phase II, and phase III clinical trials conducted in patients with colorectal cancer that document the metabolic activation of this compound and support its use in patients with advanced colorectal cancer.

Phase I study in advanced cancer patients of a diversified prime-and-boost vaccination protocol using recombinant vaccinia virus and recombinant nonreplicating avipox virus to elicit anti-carcinoembryonic antigen immune responses

PURPOSE

This trial sought to determine, for the first time, the validity in human vaccinations of using two different recombinant vaccines in diversified prime-and-boost regimens to enhance T-cell responses to a tumor antigen.

PATIENTS AND METHODS

Eighteen patients with advanced tumors expressing carcinoembryonic antigen (CEA) were randomized to receive either recombinant vaccinia (rV)-CEA followed by three avipox-CEA vaccinations, or avipox-CEA (three times) followed by one rV-CEA vaccination. Subsequent vaccinations in both cohorts were with avipox-CEA. Immunologic monitoring was performed using a CEA peptide and the enzyme-linked immunospot assay for interferon gamma production.

RESULTS

rV-CEA followed by avipox-CEA was superior to the reverse order in the generation of CEA-specific T-cell responses. Further increases in CEA-specific T-cell precursors were seen when local granulocyte-macrophage colony-stimulating factor (GM-CSF) and low-dose interleukin (IL)-2 were given with subsequent vaccinations. The treatment was extremely well tolerated. Limited clinical activity was seen using vaccines alone in this patient population. Antibody production against CEA was also observed in some of the treated patients.

CONCLUSION

rV-CEA was more effective in its role as a primer of the immune system; avipox-CEA could be given up to eight times with continued increases in CEA T-cell precursors. Future trials should use rV-CEA first followed by avipox-CEA. Vaccines specific to CEA are able to generate CEA-specific T-cell responses in patients without significant toxicity. T-cell responses using vaccines alone may be inadequate to generate significant anticancer objective responses in patients with advanced disease. Cytokines such as GM-CSF and IL-2 may play a key role in generating such responses.

The use of a rapid ELISPOT assay to analyze peptide-specific immune responses in carcinoma patients to peptide vs. recombinant poxvirus vaccines

An enzyme-linked immunosorbent spot (ELISPOT) assay for interferon gamma production has been used to analyze specific T cell responses to a Flu 9-mer peptide, and a 9-mer peptide of carcinoembryonic antigen (CEA). Assays were performed on peripheral blood mononuclear cells (PBMC) of HLA-A2-positive patients with CEA-expressing carcinomas, both before and after vaccination with CEA-based vaccines, and from HLA-A2-positive healthy blood donors. The ELISPOT assay utilized aliquots of frozen PBMC, and assays were performed after 24 h in culture with peptide to rule out any artifacts due to long-term in vitro stimulation cycles. An internal standard was used for each assay to define reproducibility of the assay, and all samples from a given patient (pre- and post-vaccination, with both the Flu and CEA peptides) were analyzed simultaneously. The results indicated a trend towards healthy blood donors having higher levels of Flu-specific T cell precursors than do colon carcinoma patients, but these results were not statistically significant (P = 0.06). On the other hand, slightly higher CEA-specific T cell responses were observed in cancer patients with CEA-expressing carcinomas than in healthy blood donors. PBMC from two CEA-based vaccine clinical trials were analyzed for T cell responses to the same CEA peptide and to the Flu control peptide. The first trial consisted of three monthly vaccinations of CEA peptide (designated PPP) in adjuvant. The second trial consisted of cohorts receiving three monthly vaccinations of avipox-CEA recombinant (designated AAA) or cohorts receiving a primary vaccination with recombinant vaccinia-CEA followed by two monthly vaccinations with avipox-CEA (designated VAA). Few, if any, CEA-specific T cell responses were seen in the PPP vaccinations, while the majority of patients receiving the poxvirus CEA recombinants demonstrated increases in CEA-specific T cell responses and no increases in Flu-specific responses. CEA-specific IgG responses were also demonstrated in patients following recombinant CEA poxvirus vaccinations. Statistical analyses of the T cell responses to the same CEA peptide demonstrated a P value of 0.028 for the recombinant poxvirus vaccines, as compared with the peptide vaccine. There were no differences seen (P = 0.37) in Flu-specific responses after these two types of CEA vaccination. These results thus provide the first evidence that poxvirus recombinant-based vaccines are more potent in the initiation of tumor-antigen-specific T cell responses than vaccines employing peptide in adjuvant, when assays are conducted in an identical manner, and in defining responses to the same peptide. These results also demonstrate for the first time that an ELISPOT assay, performed over a 24-h period and without in vitro sensitization, can be successfully used to monitor immune responses to a tumor-associated antigen in cancer patients.

A discordance of the cytochrome P450 2C19 genotype and phenotype in patients with advanced cancer

AIMS

To examine the relationship between cytochrome P450 2C19 (CYP2C19) genotype and expressed metabolic activity in 16 patients with advanced metastatic cancer.

METHODS

Individual CYP2C19 genotypes were determined by PCR-based amplification, followed by restriction fragment length analysis, and compared with observed CYP2C19 metabolic activity, as determined using the log hydroxylation index of omeprazole.

RESULTS

All 16 patients had an extensive metabolizer genotype. However, based on the antimode in a distribution of log omeprazole hydroxylation indices from healthy volunteers, four of the patients had a poor metabolizer phenotype and there was a general shift of the remaining 12 patients towards a slower metabolic phenotype. This suggests a reduction in metabolic activity for all patients relative to healthy volunteers. A careful analysis of patient medical records failed to reveal any drug interactions or other source for the observed discordance between genotype and phenotype.

CONCLUSIONS

There are no previous reports of a 'discordance' between genotype and expressed enzyme activity in cancer patients. Such a decrease in enzyme activity could have an impact on the efficacy and toxicity of chemotherapeutic agents and other drugs, used in standard oncology practice.

A safety and pharmacokinetic study of a mixed-backbone oligonucleotide (GEM231) targeting the type I protein kinase A by two-hour infusions in patients with refractory solid tumors

GEM231 is a mixed-backbone oligonucleotide targeting the regulatory subunit alpha of type I protein kinase A, which plays an important role in growth and maintenance of malignancies. Preclinically, GEM231 inhibited human cancer xenografts either alone or synergistically with chemotherapeutic agents and has demonstrated an improved metabolic stability and safety profile compared to the first-generation compounds. Objectives of this study were to define the safety profile and pharmacokinetics of GEM231 administered as 2-h IV infusions twice weekly in patients with refractory solid tumors. Fourteen patients (13 evaluable for safety) received escalating doses of GEM231 at 20-360 mg/m2 (2.5-9 mg/kg). Tumor histologies included non-small cell lung cancer, renal cell cancer, sarcoma, and others. The plasma pharmacokinetics of GEM231 were linear and predictable. Maximum plasma concentration (Cmax) reached 50-70 microg/ml (8-13 microM) at dose 360 mg/m2 and 27-32 microg/ml at dose 240 mg/m2. The plasma half-life was about 1.5 h. The only clinical toxicities were transient grade I-II fever and fatigue at doses > or = 240 mg/m2. There was no treatment-related complement activation or thrombocytopenia at any dose level, except with the first dose in one patient who had pre-existing borderline thrombocytopenia. Transient activated partial thrombin time prolongation occurred at doses > or =160 mg/m2. Dose-limiting toxicities included transient activated partial thrombin time prolongation (one of three patients at 360 mg/m2) and cumulative reversible transaminase elevation (three of three patients at 360 mg/m2 and three of six patients at 240 mg/m2 during weeks 3-10). One patient with colon cancer had stabilization of a previously rising carcinoembryonic antigen. Thus, in this first clinical evaluation of a mixed-backbone oligonucleotide in cancer patients, high plasma concentrations of GEM231 were well tolerated without significant acute toxicities, but prolonged treatment was associated with reversible transaminitis. Although 240 mg/m2 by 2-h infusion twice weekly was safe for a 4-week treatment duration, alternative dosing schedules are being tested to minimize the cumulative toxicity, which will be essential to extend the duration of therapy at the highest GEM231 dose tested.

Water disrupts stratum corneum lipid lamellae: damage is similar to surfactants

Using electron microscopy, we investigated the effect of (i) a dilute surfactant and of water alone on the ultrastructure of stratum corneum lipids in pig skin exposed in vitro at 46 degrees C, and (ii) of water alone on human skin exposed in vivo at ambient temperature. For pig skin, the surfactant sodium dodecyl sulfate disrupts stratum corneum intercellular lamellar bilayers, leading to bilayer delamination and "roll-up" in a water milieu after 1 h, extensive bilayer disruption after 6 h, and nearly complete dissociation of corneocytes after 24 h. Corneodesmosomes show progressive degradation with exposure time. Water alone also disrupts the stratum corneum, but with a slower onset. Alterations in intercellular lamellar bilayers, but not intercellular lamellar bilayer roll-up, are detected after 2 h. Intercellular lamellar bilayer roll-up occurs after 6 h. Extensive dissociation of corneocytes occurs after 24 h of water exposure. Unlike sodium dodecyl sulfate, water exposure results in the formation of amorphous intercellular lipid. Corneodesmosome degradation parallels intercellular lamellar bilayer disruption; calcium appears to offer some protection. Similar disruption of intercellular lamellar bilayers occurs in human skin in vivo at ambient temperature. Our studies show that water can directly disrupt the barrier lipids and are consistent with surfactant-induced intercellular lamellar bilayer disruption being due at least in part to the deleterious action of water. Intercellular lamellar bilayer disruption by water would be expected to enhance permeability and susceptibility to irritants; accordingly, increased attention should be given to the potential dangers of prolonged water contact. For common in vitro procedures, such as skin permeation studies or isolation of stratum corneum sheets, exposure to water should also be minimized.

Influence of endothelins and sarafotoxin 6c and L-NAME on renal vasoconstriction in the anaesthetized rat

1. An investigation was performed in pentobarbitone anaesthetized rats to compare the renal vasoconstrictor actions of endothelin-1 (ET-1), endothelin-3 (ET-3) and sarafotoxin 6c and their dependency on NO production. 2. Intra-renal arterial infusion of ET-1 and ET-3, from 1 - 1000 ng had no effect on blood pressure, but reduced renal blood flow maximally by 82 and 81% with EC50 values of 510+/-18 and 1113+/-17 ng, respectively and correspondingly increased renal vascular resistance and decreased conductance. 3. Direct renal arterial administration of sarafotoxin 6c was without effect on blood pressure but caused a maximum reduction in renal blood flow of 56% at 300 ng and had an EC50 of 86+/-4 ng. 4. Administration of the selective ETA receptor antagonist FR139317 at 0.3 and 1.0 mg kg-1 had no effect on basal levels of blood pressure, renal vascular resistance or renal blood flow. The lower dose of FR139317 had no effect on the ET-1 dose-response curve for renal blood flow while at 1.0 mg kg-1, FR139317 reduced the EC50 to 363+/-32 ng (P<0.05). 5. Infusion of L-NAME, 10 microg kg-1 min-1 increased blood pressure by approximately 15%, increased renal vascular resistance and decreased renal blood flow by some 40%. The EC50 values for renal blood flow were reduced to 358+/-68 ng (P<0.05) for ET-1, 638+/-69 ng (P<0.05) for ET-3 and 55+/-10 ng (P<0.01) for sarafotoxin 6c. The maximal reduction in renal blood flow induced by sarafotoxin 6c was raised (P<0.01) from 56% to approximately 100% and renal vascular resistance increased when NO production was blocked. 6. These results showed that the vasoconstrictor actions of ET-1 and ET-3 on resistance vessels controlling renal blood flow are mediated via ETB rather than ETA receptors. Moreover, both ET-1 and ET-3 dependent vasoconstrictions are slightly attenuated by concomitant NO production. By contrast, sarafotoxin 6c appears much more potent at the renal resistance vasculature and is much more powerfully modulated by NO.

Docetaxel and gemcitabine combinations in non-small cell lung cancer

Docetaxel and gemcitabine have been shown to be active as single agents in a variety of solid tumors. These two agents have been studied in combination with several different treatment schedules. Two phase I studies used a novel 2-week administration schedule that involved a 1-hour infusion of 35 mg/m2 to 65 mg/m2 docetaxel and gemcitabine administered as either a 30-minute infusion (2,000 to 4,000 mg/m2) or a 10 mg/m2/min infusion (1,000 to 1,200 mg/m2 total dose). Another novel phase I study evaluated the effect of drug sequence on toxicities. Patients received 30 to 40 mg/m2 docetaxel and 800 to 1,250 mg/m2 gemcitabine on days 1 and 8 every 21 days. Two phase I studies of a monthly docetaxel regimen have been conducted. Patients received 800 mg/m2 gemcitabine on days 1, 8, and 15 and 100 mg/m2 docetaxel on day 1 of a 28-day cycle. Finally, in a phase II study, patients received 900 mg/m2 gemcitabine on days 1 and 8 and 100 mg/m2 docetaxel on day 8, with granulocyte colony-stimulating factor administered on days 9 through 15. In these studies, antitumor responses were observed in lung cancer as well as a number of other histologies. Neutropenia was the most frequent dose-limiting toxicity and no difference in clinical toxicity was observed with either sequence of administration. The emerging evidence suggests, therefore, that the combination of gemcitabine and docetaxel is active in a variety of solid tumors and is well tolerated.

A Phase I and pharmacokinetic study of TNP-470 administered weekly to patients with advanced cancer

A Phase I study of angiogenesis inhibitor TNP-470 was conducted in patients with advanced cancer. TNP-470 (25-235 mg/m2) was administered i.v. over 4 h once a week to patients who had solid tumors refractory to the best available treatment or with a high risk of recurrence and who had normal renal, hepatic, and hematological function and no evidence of coagulopathy. The aims of the study were to determine the maximum tolerated dose, dose-limiting toxicities (DLTs), and the pharmacokinetics of TNP-470 given on a once-weekly schedule. Thirty-six patients, ages 23-75 (median, 54 years), with an Eastern Cooperative Oncology Group performance status of 0-2 were treated. The number of patients at each dose level (mg/m2) were 6 (25), 3 (50), 3 (75), 3 (100), 3 (133), 12 (177), and 6 (235). The principal toxicities of TNP-470 were dizziness, lightheadedness, vertigo, ataxia, decrease in concentration and short-term memory, confusion, anxiety, and depression, which occurred at doses of 133, 177, and 235 mg/m2. Two patients treated at 235 mg/m2 experienced DLT in the form of grade III cerebellar neurotoxicity after 6 weeks of treatment. Overall, these neurological symptoms were dose-related, had an insidious onset, progressively worsened with treatment, and resolved completely within 2 weeks of stopping the drug. One patient with malignant melanoma had stabilization of the previously growing disease for 27 weeks while on the treatment. Two patients, one with adenocarcinoma of the colon and the other with a soft tissue sarcoma, had no clinically detectable disease but were at high risk for recurrence at the initiation of treatment and received 13 months and > 3 years of treatment, respectively, with no evidence of disease recurrence. The remaining patients had progression of their disease after 1-6 months of treatment. The mean plasma half-life (t(1/2)) of TNP-470 and its principal metabolite, AGM-1883, were extremely short (harmonic mean, t(1/2) of 2 and 6 min, respectively) with practically no drug detectable in the plasma by 60 min after the end of the infusion. MII, an inactive metabolite, had a considerably longer t(1/2) of approximately 2.6 h. Mean peak TNP-470 concentrations were > or = 400 ng/ml at doses > or = 177 mg/m2. On the basis of this study, the maximum tolerated dose of TNP-470 administered on a weekly schedule was 177 mg/m2 given i.v over 4 h. The principal DLT was neurotoxicity, which appeared to be dose-related and was completely reversible. On the basis of the short plasma t(1/2) of TNP-470, exploration of a prolonged i.v. infusion schedule is warranted.

A pilot trial of GM-CSF and MDX-H210 in patients with erbB-2-positive advanced malignancies

MDX-H210 is a chemically, cross-linked, half-humanized bispecific antibody composed of F(ab') fragment from monoclonal antibody (mAb) H22 that binds to the high-affinity receptor Fc gamma RI and F(ab') of mAb 520C9 that recognizes the erbB-2 (HER2/neu) oncoprotein. In a previous trial, the murine bispecific, MDX-210 at a dose of 7 mg/m2, was well tolerated and activated monocytes and macrophages in vivo in doses as low as 0.35 mg/m2. In our multidose trial, granulocyte-macrophage colony-stimulating factor, which increases and activates potential effector cells, was given on days 1-4 at 250 micrograms/m2 s.c. and MDX-H210 was given on day 4 weekly for 4 consecutive weeks. Thirteen patients were treated at dose levels of 1, 3.5, 7, 10, 15, and 20 mg/m2 without dose-limiting toxicity. Fever, chills, and rigors occurred during and up to 2 h postinfusion and correlated with the time to peak levels of tumor necrosis factor-alpha (median 88.2 pg/ml; range 15.6-887 pg/ml) and interleukin-6 (median 371 pg/ml; range 175-2,149 pg/ml). By the fourth consecutive week of treatment the side effects and cytokine levels decreased significantly. Human antibispecific antibody (HABA) levels were increased by 200- to 500-fold above pretreatment levels in 5 of 11 evaluable patients after 3 weeks of treatment. The monocyte and granulocyte population increased on days 4 and 11 (median 44%; range 18-68% and 42%; 19-71%), respectively, for monocytes and (60%; 43-75% and 74%; 54-82%) on days 4 and 11 for granulocytes. There was a significant decrease in the monocyte populations immediately after MDX-H210 administration (median decrease 73%; range 42-94%) and (52%; 12-72%) on days 4 and 11, respectively. Ten patients completed 4 weeks of treatment. One patient had a 48% reduction in an index lesions and six patients had stable disease at the time of evaluation. Three patients progressed before the fourth week. The therapy was generally well tolerated with toxicity, primarily, limited to the days of treatment.

A Phase I study of LGD1069 in adults with advanced cancer

LGD1069 [Targretin; 4-[1-(5,6,7,8-tetrahydro-3,5,5,8,8-pentamethyl-2-naphtalenyl) propenyl] benzoic acid] is a novel synthetic retinoid X receptor-selective retinoid that has been recently identified. The goals of this study were to determine the safety, toxicity, pharmacokinetics (PKs), and metabolic profile of LGD1069 in advanced cancer patients. Sixty patients received oral LGD1069 at doses ranging from 5-1000 mg/m2/day with PK sampling performed on days 1 and 15. No dose-limiting toxicities (DLTs) were observed up to the 500 mg/m2/day dose level. DLT observed at and above 650 mg/m2/day included skin desquamation, hyperbilirubinemia, transaminase elevation, leukopenia, and diarrhea. Asymptomatic, dose-related alterations in lipid and thyroid metabolism were also observed. DLTs frequently observed with retinoic acid receptor-selective retinoids and pan agonists, including headache, mucocutaneous toxicity, and hypercalcemia, were not dose-limiting with LGD1069. Day 1 LGD1069 Cmax and area under the curve values increased dose-proportionately up to 800 mg/m2/day. Repeat-dose (day 15) area under the curve values varied between 25 and 105% of day 1 values. Although no objective tumor responses were observed, tumor progression may have been substantially arrested or delayed in non-small cell lung cancer (5 of 16) and in head and neck cancer (1 of 5), as well as other tumor types. At the higher dose levels, the molar concentration of LGD1069 was up to 10-fold higher than observed with other retinoids, yet toxicity was minimal. LGD1069 is an retinoid X receptor-selective retinoid agonist with a more favorable PK and toxicity profile than previously studied retinoids and merits further investigation as a chemopreventive and anticancer agent. On the basis of this Phase I trial, the recommended Phase II dose is 500 mg/m2/day.

Phase I study in cancer patients of a replication-defective avipox recombinant vaccine that expresses human carcinoembryonic antigen

PURPOSE

A phase I clinical trial in patients with advanced carcinoma was conducted, using a replication-defective avipox vaccine containing the gene for the human carcinoembryonic antigen (CEA). The canarypox vector, designated ALVAC, has the ability to infect human cells but cannot replicate.

PATIENTS AND METHODS

The recombinant vaccine, designated ALVAC-CEA, was administered intramuscularly three times at 28-day intervals. Each cohort of six patients received three doses of either 2.5 x 10(5), 2.5 x 10(6), or 2.5 x 10(7) plaque-forming units of vaccine.

RESULTS

The vaccine was well tolerated at all dose levels and no significant toxicity was attributed to the treatment. No objective antitumor response was observed during the trial in patients with measurable disease. Studies were conducted to assess whether ALVAC-CEA had the ability to induce cytolytic T-lymphocyte (CTL) responses in patients with advanced cancer. Peripheral blood mononuclear cells (PBMCs) from patients with the MHC class I A2 allele were obtained before vaccine administration and 1 month after the third vaccination. Peripheral blood mononuclear cells were incubated with the CEA immunodominant CTL epitope carcinoembryonic antigen peptide-1 and interleukin 2 and quantitated using CTL precursor frequency analysis. In seven of nine patients evaluated, statistically significant increases in CTL precursors specific for CEA were observed in PBMCs after vaccination, compared with before vaccination.

CONCLUSION

These studies constitute the first phase I trial of an avipox recombinant in cancer patients. The recombinant vaccine ALVAC-CEA seems to be safe and has been demonstrated to elicit CEA-specific CTL responses. These studies thus form the basis for the further clinical exploration of the ALVAC-CEA recombinant vaccine in phase I/II studies in protocols designed to enhance the generation of human T-cell responses to CEA.

Determination of the antitumor agent depsipeptide in plasma by liquid chromatography on serial octadecyl stationary phases

A high-performance liquid chromatographic assay has been developed and validated for the determination of the antitumor agent depsipeptide (FR-901228) in plasma samples from patients with advanced cancer. After the plasma proteins were precipitated with acetonitrile, the supernatant was extracted with ethylacetate. Depsipeptide was chromatographed on two serial octadecylsilica stationary phases using a mobile phase consisting of acetonitrile-potassium phosphate buffer (0.03 M, pH 3) (27:73, v/v), at a flow-rate of 2.0 ml/min and at ambient temperature. The method was linear over a 50 to 2000 ng/ml range and the intra- and inter-day coefficients of variations were less than 8%. The method was applied to the determination of the plasma concentration-time profile for 14 patients with advanced cancer receiving from 1 to 7.5 mg/m2 of depsipeptide per day as a continuous 4-h infusion.

Phase I study of 9-cis-retinoic acid (ALRT1057 capsules) in adults with advanced cancer

9-cis-Retinoic acid (9-cis-RA) and all-trans-RA (ATRA) are naturally occurring hormones. The nuclear receptors that mediate the effects of retinoids are the retinoic acid receptors (RARs) and the retinoid X receptors (RXRs). ATRA binds RAR with high affinity but does not bind to RXR, whereas 9-cis-RA, an isomer of ATRA, is a ligand that binds and transactivates both RARs and RXRs. The goals of this study were to determine the safety, tolerability, pharmacokinetics, and metabolic profile of 9-cis-RA in advanced cancer patients. Forty-one patients received oral 9-cis-RA (ALRT1057; Panretin capsules) at doses ranging from 5-140 mg/m2/day. Twenty-six patients were treated once daily with up to 140 mg/m2; a subsequent cohort of 15 patients were treated twice daily (b.i.d.) at 100-140 mg/m2/day (50, 60, and 70 mg/m2 b.i.d.) to evaluate a b.i.d. dosing regimen. Headache was the most frequent adverse event and was dose limiting in 3 of 41 patients. Skin toxicity was the next most common toxicity and was seen in 11 of 41 patients; it was typically mild and limited to skin dryness and erythema. Other toxicities included conjunctivitis, flushing, diarrhea, transaminitis, hypercalcemia, and asymptomatic hypertryglyceridemia. Toxicities were typically dose related, occurred primarily above 83 mg/m2/day, and were not ameliorated by b.i.d. dosing. No tumor responses were observed. The mean day 1 area under the plasma concentration-time curve and peak plasma concentration values were dose-proportional over all dose levels, whereas day 15 area under the plasma concentration-time curve and peak plasma concentration values were nonlinear above 83 mg/m2/day, suggesting that 9-cis-RA induced its own metabolism at doses equal to and above 140 mg/m2/day. 9-cis-RA is a retinoid receptor pan agonist with a more favorable pharmacokinetic and toxicity profile than that observed with previously studied retinoids and merits further investigation.

Phase I trial of orally administered pentosan polysulfate in patients with advanced cancer

Tumor angiogenesis is critically important to tumor growth and metastasis. We have shown that pentosan polysulfate (PPS) is an effective inhibitor of heparin-binding growth factors in vitro and can effectively inhibit the establishment and growth of tumors in nude mice. Following completion of our Phase I trial of s.c. administered PPS, we performed a Phase I trial of p.o. administered PPS in patients with advanced cancer to determine the maximum tolerated dose (MTD) and toxicity profile and to search for any evidence for biological activity in vivo. Patients diagnosed with advanced, incurable malignancies who met standard Phase I criteria and who did not have a history of bleeding complications were enrolled, in cohorts of three, to receive PPS p.o. t.i.d., at planned doses of 180, 270, 400, 600, and 800 mg/m2. Patients were monitored at least every 2 weeks with physical exams and weekly with hematological, chemistry, stool hemoccult, and coagulation blood studies, and serum and urine samples for PPS and basic fibroblastic growth factor (bFGF) levels were also taken. The PPS dose was escalated in an attempt to reach the MTD. Eight additional patients were enrolled at the highest dose to further characterize the toxicity profile and biological in vivo effects of PPS. A total of 21 patients were enrolled in the three cohorts of doses 180 (n = 4), 270 (n = 3), and 400 (n = 14) mg/m2. The most severe toxicities seen were grade 3 proctitis and grade 4 diarrhea; however, 20 of the 21 patients had evidence of grade 1 or 2 gastrointestinal (GI) bleeding. These toxicities became evident at a much earlier time point as the dose was increased, but their severities were similar at all dose levels. There were no objective responses, although three patients had prolonged stabilization of previously progressing disease. Pharmacokinetic analysis suggested marked accumulation of PPS upon chronic administration. Serum and urine bFGF levels failed to show a consistent, interpretable pattern; however the data suggested an inverse relationship between PPS and bFGF levels in vivo. A MTD could not be determined using the daily t.i.d. dosing schedule due to the development of grade 3/4 GI toxicity (proctitis) at all dose levels studied. PPS, administered p.o. at doses of 400 mg/m2 t.i.d., did not cause significant systemic toxicity, but most patients developed moderate-to-severe GI toxicity within 1-2 months. The cause of the GI toxicity was unclear, but it was readily reversible upon cessation of the agent. The suggestion of an inverse relationship between PPS and bFGF supports further study of PPS as an antiangiogenic agent. The tested doses and schedule cannot be recommended for further study. Subsequent murine experiments showed PPS to be more effective as an anticancer agent when it is given intermittently. We propose a study of PPS given on a weekly schedule in further clinical trials.

TNM staging of pancreatic carcinoma using helical CT

OBJECTIVE

The purpose of this study was to determine the accuracy of helical CT scanning in predicting the stage of carcinoma of the exocrine pancreas using TNM staging guidelines and in predicting resectability of carcinoma of the exocrine pancreas.

MATERIALS AND METHODS

Twenty-six patients with proven adenocarcinoma of the pancreas underwent uniphasic or biphasic helical CT scanning. Two observers unaware of the patient's surgical stage evaluated the CT examinations using the TNM system (with specific assessment and description of disease sites). In addition, the two observers rated confidence of nonresectability using a 5-point scale (ranging from 1, definitely resectable, to 5, definitely not resectable). Observer results and preoperative interpretations were compared with surgical findings.

RESULTS

Nineteen of 26 patients had nonresectable disease. The combined observer scores showed correct determination of T stage in 77% of patients, of N stage in 58%, and of M stage in 79%. The overall accuracy in determining lack of resectability was 96% and 84% for the two observers. All errors in determining resectable versus nonresectable disease occurred when the observer was not maximally confident of his or her diagnosis.

CONCLUSION

Helical CT is an effective screening technique for assessing T and M stages of pancreatic carcinoma. However, helical CT is poor at detecting regional lymph node involvement. In patients with equivocal T-stage findings (such as questionable venous involvement), other studies such as endoscopic sonography may be of value.

Biochemical modulation in the treatment of advanced cancer: a study of combined leucovorin, fluorouracil, and iododeoxyuridine

Multiple studies have shown that leucovorin-fluorouracil regimens are modestly superior to fluorouracil alone in the treatment of advanced colorectal cancer. Laboratory data suggest that iododeoxyuridine could further enhance the efficacy of leucovorin-fluorouracil regimens. This report describes the Phase I clinical evaluation of a leucovorin-fluorouracil-iododeoxyuridine chemotherapy regimen. Twenty-four patients received treatment with leucovorin (500 mg/m2), fluorouracil (500 mg/m2), and iododeoxyuridine (escalating doses) on days 1 and 8 of a 21-day cycle. The maximum tolerated dose of iododeoxyuridine was 1200 mg/m2, with a recommended Phase II dose of 1000 mg/m2. Myelosuppression (leukopenia) was dose limiting; other commonly observed treatment toxicities were nausea/vomiting, mucositis, and hyperlacrimation. Although the 1200 mg/m2 dose was tolerated during the initial few cycles of therapy, chronic administration could not be maintained secondary to dose-limiting neutropenia. Since neutropenia was dose limiting, in a follow-up study, 10 patients received a modified regimen (treatment on days 1 and 6 instead of days 1 and 8) with the addition of granulocyte colony-stimulating factor (days 8-19). The addition of granulocyte colony-stimulating factor, however, did not permit further escalation of the iododeoxyuridine dose. Three partial responses and six minor responses were observed. Phase II studies of this regimen are ongoing in advanced colorectal and advanced pancreatic cancer to determine response rates in these diseases.

Preclinical and clinical experience with cisplatin resistance

Despite the general lack of clinical evidence supporting the preclinical data, there have been many attempts to overcome cisplatin resistance in clinical situations. These efforts have focused on both the proposed mechanisms of resistance as well as novel approaches to renew efficacy. In this article, the authors summarize the available clinical studies that have intentionally or serendipitously uncovered modulators of cisplatin sensitivity.

The clinical experience with antiangiogenic agents

Antiangiogenic agents have been recently recognized to be potentially useful in the treatment of malignant processes. There has been a resulting flood of these agents into the clinical research field, forcing researchers to consider the unique problems which these agents pose. As these are agents with a novel, angiostatic mechanism of action, new clinical trial designs may become necessary to move these agents from the phase 1 level on to clinical use. Currently, several of these agents are being or have been tested in clinical trials. In this article, we review the available clinical data with antiangiogenic agents from other investigators, and our own experience with pentosan polysulfate.