Clinical trial designs for the early clinical development of therapeutic cancer vaccines

There are major differences between therapeutic tumor vaccines and chemotherapeutic agents that have important implications for the design of early clinical trials. Many vaccines are inherently safe and do not require phase I dose finding trials. Patients with advanced cancers and compromised immune systems are not good candidates for assessing either the toxicity or efficacy of therapeutic cancer vaccines. The rapid pace of development of new vaccine candidates and the variety of possible adjuvants and modifications in method of administration makes it important to use efficient designs for clinical screening and evaluation of vaccine regimens. We review the potential advantages of a wide range of clinical trial designs for the development of tumor vaccines. We address the role of immunological endpoints in early clinical trials of tumor vaccines, investigate the design implications of attempting to use disease stabilization as an end point and discuss the difficulties of reliably utilizing historical control data. Several conclusions for expediting the clinical development of effective cancer vaccines are proposed.

How to optimize the drop plate method for enumerating bacteria

The drop plate (DP) method can be used to determine the number of viable suspended bacteria in a known beaker volume. The drop plate method has some advantages over the spread plate (SP) method. Less time and effort are required to dispense the drops onto an agar plate than to spread an equivalent total sample volume into the agar. By distributing the sample in drops, colony counting can be done faster and perhaps more accurately. Even though it has been present in the laboratory for many years, the drop plate method has not been standardized. Some technicians use 10-fold dilutions, others use twofold. Some technicians plate a total volume of 0.1 ml, others plate 0.2 ml. The optimal combination of such factors would be useful to know when performing the drop plate method. This investigation was conducted to determine (i) the standard deviation of the bacterial density estimate, (ii) the cost of performing the drop plate procedure, (iii) the optimal drop plate design, and (iv) the advantages of the drop plate method in comparison to the standard spread plate method. The optimal design is the combination of factor settings that achieves the smallest standard deviation for a fixed cost. Computer simulation techniques and regression analysis were used to express the standard deviation as a function of the beaker volume, dilution factor, and volume plated. The standard deviation expression is also applicable to the spread plate method.

Biodistribution of NX211, liposomal lurtotecan, in tumor-bearing mice

Prolonging tumor exposure to topoisomerase I inhibitors has been correlated to enhance the efficacy of those agents. Lurtotecan, a water-soluble camptothecin analog, was formulated as a liposomal drug, NX211, to enhance the delivery of drug to tumors. Tumor-bearing mice were treated with either [14C]NX211 containing [14C]lurtotecan, [3H]NX211 containing [3H]phosphatidylcholine or [14C]lurtotecan, euthanized at selected times post-injection, and tissues, plasma, urine and feces were collected. These studies demonstrated that KB tumors of [14C]NX211-treated mice had approximately 70-fold greater concentrations of [14C]lurtotecan at 24 h, respectively, compared to concentrations of [14C]lurtotecan of the KB tumors of [14C]lurtotecan-treated mice. The area under curve (AUC) from 0 to 48 h of [14C]lurtotecan for the KB tumors of [14C]NX211-treated animals was over 17-fold greater than the AUC of [14C]lurtotecan for the tumors of [14C]lurtotecan-treated animals. Treatment with [3H]NX211 demonstrated that the lipid component continually accumulated over 24 h in the tissues. HPLC analysis of extracted material from tumors of [14C]NX211-treated mice showed that more than 95% of the radioactive material was intact [14C]lurtotecan. These findings are one of the keys justifying the development of a liposomal formulation of lurtotecan, which has the intent to increase tumor exposure and increase antitumor efficacy.

Preoperative identification of psychiatric illness in aesthetic facial surgery patients

The purpose of this study was to evaluate the preoperative use of a two-part standardized assessment program (Prime-MD, Biometrics Research Department, New York State Psychiatric Institute) to objectively detect psychiatric disorders in facial plastic surgery patients, and to compare its use to findings identified by the facial plastic surgeon. Seventy-five new patients requesting aesthetic facial surgery at two academic centers and two private practice locations were evaluated.

Domestic swine model for the assessment of chemical warfare agent-anesthetic interactions: some effects of sulfur mustard

A domestic swine model was developed to examine the interaction of chemical warfare agents with anesthetics and other drugs used during general anesthesia. Animals were fully instrumented, and clinically relevant physiological parameters were monitored throughout the experimental procedures. Exposure of animals under halothane anesthesia to the chemical warfare agent sulfur mustard (HD; 1 mg/kg intravenous) produced mild signs of systemic intoxication during the subsequent 5 hours. Induction doses of ketamine 1 hour after HD exposure resulted in periods of profound apnea, with continued respiratory distress for the next 2 hours. When animals were treated with HD 1 hour after the initiation of ketamine anesthesia, severe and persistent convulsion-like muscular activity was observed within 45 minutes of HD administration. This nonpurposeful activity was not ameliorated by diazepam but was dramatically reduced or eliminated by resumption of halothane anesthesia. Treatment of HD-intoxicated pigs with succinylcholine produced a prolonged apnea resulting in death. In these apparently mildly HD-intoxicated animals, the introduction of ketamine or succinylcholine can rapidly induce potentially life-threatening situations.

The incidence of sports-related facial trauma in children

We conducted a survey of physician members of the American Academy of Facial Plastic and Reconstructive Surgery to determine the incidence and nature of facial traumas seen in their practices. We solicited information on the anatomic location of each injury, the severity of the trauma, and whether the injury occurred during a sports activity. According to the responses, 21% of facial fractures and 29% of nasal fractures were experienced by patients aged 17 years and younger who were participating in sports. We believe that many such injuries can be prevented with greater use of protective equipment.

Alcoholic hepatitis-the case for intensive management

Alcoholic hepatitis is a common condition with a high mortality. Although treatment options for established alcoholic hepatitis are limited, many of the complications of this condition are preventable. This case report and discussion illustrate the important role of early diagnosis and intervention in this patient group. Important management points are stressed to aid physicians who may encounter this condition rarely.

Antitumor efficacy, pharmacokinetics, and biodistribution of NX 211: a low-clearance liposomal formulation of lurtotecan

Lurtotecan is a clinically active water-soluble camptothecin analogue that has been formulated into a low-clearance unilamellar liposome, NX 211. Comparative studies between free drug and NX 211 have been performed assessing pharmacokinetics in nude mice, tissue distribution in tumor-bearing mice, and antitumor efficacy in xenografts. Compared with lurtotecan, NX 211 demonstrated a significant increase in plasma residence time and a subsequent 1500-fold increase in the plasma area under the drug concentration curve. The volume of distribution was also greatly restricted, suggesting altered tissue distribution. Evaluation of tissues 24 h after administration of either [14C]NX 211 or [14C]lurtotecan to ES-2 tumor-bearing mice demonstrated a 40-fold increase in radiolabeled compound in the tumors of NX 211-treated mice compared with mice treated with lurtotecan. In single-dose efficacy studies, NX 211 produced a consistent 3-fold or greater increase in therapeutic index compared with lurtotecan in both the KB and ES-2 xenograft models. When compared at equitoxic levels in repeat-dose efficacy studies, NX 211 generated durable cures lasting >60 days and a 2-8-fold increase in log10 cell kill, compared with lurtotecan and topotecan, respectively. Together, these data demonstrate that NX 211 has significant therapeutic advantage over lurtotecan and that the improved antitumor activity is consistent with increased exposure and enhanced drug delivery to tumor sites.

Imaging and phase I study of 111In- and 90Y-labeled anti-LewisY monoclonal antibody B3

B3 is a murine monoclonal antibody (mAb) that recognizes a LewisY carbohydrate antigen present on the surface of many carcinomas. An imaging and Phase I trial was performed to study the ability of 111In-mAb B3 to image known metastasis and determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), kinetics, and biodistribution of 90Y-mAb B3. Patients (n = 26) with advanced epithelial tumors that express the LewisY antigen were entered. All patients received 5 mCi of 111In-mAb B3 for imaging. 90Y-mAb B3 doses were escalated from 5 to 25 mCi in 5-mCi increments. 111In-mAb B3 and 90Y-mAb B3 were coadministered over a 1-h infusion. Definite tumor imaging was observed in 20 of 26 patients. Sites imaged included lung, liver, bone, and soft tissues. The MTD of 90Y-mAb B3 was determined to be 20 mCi. The DLTs were neutropenia and thrombocytopenia. Tumor doses ranged from 7.7 to 65.1 rad/mCi. 111In- and 90Y-mAb B3 serum pharmacokinetics (n = 23) were found to be similar. The amount of B3 administered (5, 10, and 50 mg) did not alter the pharmacokinetics. Bone marrow biopsies (n = 23) showed 0.0038+/-0.0016% of injected dose/gram for 111In-mAb B3 compared to 0.0046+/-0.0017% of injected dose/gram for 90Y-mAb B3 (P = 0.009). When given to patients with carcinomas that express the LewisY antigen, 111In-mAb B3 demonstrated good tumor localization. The MTD of 90Y-mAb B3 is 20 mCi, with myelosuppression as the DLT. Higher doses of radioactivity need to be delivered to achieve an antitumor effect. Humanized mAb B3 is being developed for evaluation in radioimmunotherapy. A clinical trial to explore the use of higher doses of 90Y-mAb B3 with autologous stem cell support is planned.

Persistent neuroprotection with prolonged postischemic hypothermia in adult rats subjected to transient middle cerebral artery occlusion

Postischemic hypothermia provides long-lasting neuroprotection against global cerebral ischemia in adult rats and gerbils. Studies indicate that hypothermia must be prolonged (e.g., 24 h) to indefatigably salvage hippocampal CA1 neurons. Delayed hypothermia also reduces focal ischemic injury. However, no study has examined long-term outcome following postischemic hypothermia in adult animals. Furthermore, most studies examined only brief hypothermia (e.g., 3 h). Since previous studies may have overestimated long-term benefit and have likely used suboptimal durations of hypothermia, we examined whether prolonged cooling would attenuate infarction at a 2-month survival time following middle cerebral artery occlusion (MCAo) in rats. Adult male Wistar rats were implanted with telemetry brain temperature probes and later subjected to 30 min of normothermic MCAo (contralateral to side of probe placement) or sham operation. Ischemia was produced by the insertion of an intraluminal suture combined with systemic hypotension (60 mm Hg). Sham rats and one ischemic group controlled their own postischemic temperature while another ischemic group was cooled to 34 degrees C for 48 h starting at 30 min following the onset of reperfusion. The infarct area was quantified after a 2-month survival time. Normothermic MCAo resulted in almost complete striatal destruction (91% loss +/- 12 SD) with extensive cortical damage (36% +/- 16 SD). Delayed hypothermia treatment significantly reduced cortical injury to 10% +/- 10 SD (P < 0.001) while striatal injury was marginally reduced to 79% loss +/- 17 SD (P < 0.05). Delayed hypothermia of only 34 degrees C provided long-lasting cortical and striatal protection in adult rats subjected to a severe MCAo insult. These results strongly support the clinical assessment of hypothermia in acute stroke.

Immigrant and Native-born Mexican-American parents' involvement in a public school: a preliminary study

Mexican-American parents of Texas elementary school students were surveyed to compare the types of school involvement in which immigrant and U.S.-born parents engage. Those completing the questionnaire included 246 mothers and 39 fathers born in Mexico as well as 95 mothers and 13 fathers born in the United States. More immigrant parents than U.S.-born parents indicated they helped their children with school work, attended school board meetings, volunteered at school, participated in parent-teacher conferences, went to school functions, served as room mother, engaged in school fundraising, and were present during parent advisory committee meetings.

Health effects of depleted uranium on exposed Gulf War veterans

A small group of Gulf War veterans possess retained fragments of depleted uranium (DU) shrapnel, the long-term health consequences of which are undetermined. We evaluated the clinical health effects of DU exposure in Gulf War veterans compared with nonexposed Gulf War veterans. History and follow-up medical examination were performed on 29 exposed veterans and 38 nonexposed veterans. Outcome measures employed were urinary uranium determinations, clinical laboratory values, and psychiatric and neurocognitive assessment. DU-exposed Gulf War veterans with retained metal shrapnel fragments are excreting elevated levels of urinary uranium 7 years after first exposure (range 0.01-30.7 microg/g creatinine vs 0.01- 0.05 microg/g creatinine in the nonexposed). The persistence of the elevated urine uranium suggests on-going mobilization from a storage depot which results in a chronic systemic exposure. Adverse effects in the kidney, a presumed target organ, are not present at this time, though other effects are observed. Neurocognitive examinations demonstrated a statistical relationship between urine uranium levels and lowered performance on computerized tests assessing performance efficiency. Elevated urinary uranium was statistically related to a high prolactin level (>1.6 ng/ml; P=0.04). More than 7 years after first exposure, DU-exposed Gulf War veterans with retained metal fragments continue to excrete elevated concentrations of urinary uranium. Effects related to this are subtle perturbations in the reproductive and central nervous systems.

Liposomal lurtotecan (NX211): determination of total drug levels in human plasma and urine by reversed-phase high-performance liquid chromatography

Lurtotecan (GI147211; LRT) is a semisynthetic and water-soluble analogue of the topoisomerase I inhibitor camptothecin. To determine whether the therapeutic efficacy of LRT in patients could be improved, the drug was encapsulated in liposomes (NX211; Gilead Sciences). In order to allow accurate description of the pharmacokinetic behavior of NX211 in cancer patients, we have developed sensitive RP-HPLC assays with fluorescence detection (lambdaex=378 nm; lambdaem=420 nm) for the determination of total LRT levels in human plasma and urine. Sample pretreatment involved deproteinization with 10% (w/v) aqueous perchloric acid-acetonitrile (2:1, v/v), and chromatographic separations were achieved on an Inertsil-ODS 80A analytical column. The lower limit of quantitation (LLQ) was established at 1.00 ng/ml in plasma (200-microl sample) and at 100 ng/ml in urine (200 microl of 40-fold diluted sample). The within-run and between-run precisions were <7.5%. LRT concentrations in urine of <100 ng/ml were determined by a modified procedure comprising a single solvent extraction with n-butanol-diethyl ether (3:4, v/v). In this assay, the fluorescence signal of LRT was increased 14-fold prior to detection by post-column exposure to UV light (254 nm) in a photochemical reaction unit. The LLQ of this assay was 0.500 ng/ml (150-microl sample) and the within-run and between-run precisions were <10%.

Which glioblastoma multiforme patient will become a long-term survivor? A population-based study

In this clinical and histopathological study, the frequency of long-term glioblastoma multiforme (GBM) survivors (LTGBMSs) was determined in a population-based study. The Alberta Cancer Registry was used to identify all patients diagnosed with GBM in Alberta between January 1, 1975, and December 31, 1991. Patient charts were reviewed and histology reexamined. LTGBMSs were defined as GBM patients surviving 3 years after diagnosis. Each LTGBMS was compared with 3 age-, sex-, and year of diagnosis-matched controls, and patient/treatment or tumor characteristics that predicted long-term survival were determined. There were 689 GBMs diagnosed in the study period; 15 (2.2%) of these patients survived 3 years. LTGBMSs (average age, 43.5 +/- 3.3 years) were significantly younger when compared with all GBM patients (average age, 53.0 +/- 0.56 years). LTGBMSs had a higher Karnofsky Performance Status score at diagnosis compared with controls. LTGBMSs were much more likely to have had a gross total resection and adjuvant chemotherapy than control GBM patients. Tumors from LTGBMSs tended to have fewer mitoses and a significantly lower Ki-67 cellular proliferation index compared with controls. Radiation-induced dementia was common and disabling in LTG-BMSs. In conclusion, conventionally treated GBM patients in an unselected population have a very small chance of long-term survival. The use of aggressive surgical resection and adjuvant chemotherapy may make long-term survival more likely in GBM patients if their performance status is high at diagnosis.

Cloning of TACC1, an embryonically expressed, potentially transforming coiled coil containing gene, from the 8p11 breast cancer amplicon

Amplification of several chromosomal regions have been observed in human breast carcinomas. One such region, 8p11, is amplified in 10-15% of tumor samples. Although the FGFR1 gene is located close to this region, and is often included within the amplicon, the observation that tumors exhibiting 8p11 amplification do not always overexpress FGFR1 suggests that another gene located close to FGFR1 is involved in the tumorigenic process. We now report the precise location of four expressed sequence tags (ESTs) within this region and the cloning of a novel gene, designated TACC1 (transforming acidic coiled coil gene 1), which encodes an 8 kb transcript and which is expressed at high levels during early embryogenesis. Constitutive expression of this gene under the control of the cytomegalovirus (CMV) promoter in mouse fibroblasts, results in cellular transformation and anchorage independent growth, suggesting that inappropriate expression can impart a proliferative advantage. This observation raises the possibility that amplification of TACC1 could promote malignant growth, thereby making TACC1 an attractive candidate for the gene promoting tumorigenicity as a result of the 8p11 amplification in human breast cancers.

Characteristics of depression as assessed by the Diagnostic Assessment for the Severely Handicapped-II (DASH-II)

Fifty-seven individuals with severe and profound mental retardation (18 with a DSM-IV diagnosis of depression, 19 with a Diagnostic Statistical Manual, 4th edition diagnosis of autism, and 20 who meet no criteria for an emotional disorder) were studied. The validity of the Diagnostic Assessment for the Severely Handicapped II depression subscale was evaluated to determine its value in categorizing individuals in these two groups. Suggestions were made for diagnosing depression in persons with severe and profound mental retardation. In a second study the above individuals were compared on symptomology to assess comorbidity with related symptoms. These "core," peripheral, or associated features of depression were identified. Implications of the findings for describing and defining depression in these persons are discussed.