A phase I clinical trial with monoclonal antibody ch806 targeting transitional state and mutant epidermal growth factor receptors

An array of cell-surface antigens expressed by human cancers have been identified as targets for antibody-based therapies. The great majority of these antibodies do not have specificity for cancer but recognize antigens expressed on a range of normal cell types (differentiation antigens). Over the past two decades, our group has analyzed thousands of mouse monoclonal antibodies for cancer specificity and identified a battery of antibodies with limited representation on normal human cells. The most tumor-specific of these antibodies is 806, an antibody that detects a unique epitope on the epidermal growth factor receptor (EGFR) that is exposed only on overexpressed, mutant, or ligand-activated forms of the receptor in cancer. In vitro immunohistochemical specificity analysis shows little or no detectable 806 reactivity with normal tissues, even those with high levels of wild-type (wt)EGFR expression. Preclinical studies have demonstrated that 806 specifically targets a subset of EGFR expressed on tumor cells, and has significant anti-tumor effects on human tumor xenografts, primarily through abrogation of signaling pathways. The present clinical study was designed to examine the in vivo specificity of a chimeric form of mAb 806 (ch806) in a tumor targeting/biodistribution/pharmacokinetic analysis in patients with diverse tumor types. ch806 showed excellent targeting of tumor sites in all patients, no evidence of normal tissue uptake, and no significant toxicity. These in vitro and in vivo characteristics of ch806 distinguish it from all other antibodies targeting EGFR.

Phase I Trial of 131I-huA33 in Patients with Advanced Colorectal Carcinoma

PURPOSE

Humanized monoclonal antibody A33 (huA33) targets the A33 antigen which is expressed on 95% of colorectal cancers. A previous study has shown excellent tumor-targeting of iodine-131 labeled huA33 (131I-huA33). Therefore, we did a phase I dose escalation trial of 131I-huA33 radioimmunotherapy.

EXPERIMENTAL DESIGNS

Fifteen patients with pretreated metastatic colorectal carcinoma each received two i.v. doses of 131I-huA33. The first was an outpatient trace-labeled "scout" dose for biodistribution assessment, followed by a second "therapy" dose. Three patients were treated at 20, 30, and 40 mCi/m2 dose levels, and six patients at 50 mCi/m2 to define the maximum tolerated dose.

RESULTS

Hematologic toxicity was 131I dose-dependent, with one episode of grade 4 neutropenia and two episodes of grade 3 thrombocytopenia observed at 50 mCi/m2. The maximum tolerated dose was determined to be 40 mCi/m2. There were no acute infusion-related adverse events, and gastrointestinal toxicity was not observed despite uptake of 131I-huA33 in bowel. Seven patients developed pruritus or rash, which was not related to 131I dose. There was excellent tumor-targeting of 131I-huA33 shown in all patients. The serum T1/2beta of 131I-huA33 was (mean +/- SD) 135.2 +/- 46.9 hours. The mean absorbed tumor dose was 6.49 +/- 2.47 Gy/GBq. Four patients developed human anti-human antibodies. At restaging, 4 patients had stable disease, whereas 11 patients had progressive disease.

CONCLUSION

Radioimmunotherapy using 131I-huA33 shows promise in targeting colorectal tumors, and is deliverable at a maximum tolerated dose of 40 mCi/m2. Further studies of 131I-huA33 in combination with chemotherapy are planned.

A phase I biodistribution and pharmacokinetic trial of humanized monoclonal antibody Hu3s193 in patients with advanced epithelial cancers that express the Lewis-Y antigen

PURPOSE

We report a first-in-man trial of a humanized antibody (hu3S193) against the Le(y) antigen.

EXPERIMENTAL DESIGN

Patients with advanced Le(y)-positive cancers received four infusions of hu3S193 at weekly intervals, with four dose levels (5, 10, 20, and 40 mg/m(2)). The first infusion of hu3S193 was trace labeled with Indium-111, and biodistribution, pharmacokinetics, tumor uptake, and immune response were evaluated in all patients.

RESULTS

A total of 15 patients (7 male/8 female; age range, 42-76 years; 6 breast, 8 colorectal cancer, and 1 non-small-cell lung cancer) were entered into the study. Transient grade 1 to 2 nausea and vomiting was observed following infusion of hu3S193 at the 40 mg/m(2) dose level only. There was one episode of dose-limiting toxicity with self-limiting Common Toxicity Criteria grade 3 elevated alkaline phosphatase observed in one patient with extensive liver metastases. The biodistribution of (111)In-hu3S193 showed no evidence of any consistent normal tissue uptake, and (111)In-hu3S193 uptake was observed in cutaneous, lymph node, and hepatic metastases. Hu3S193 displayed a long serum half-life (T(1/2)beta = 189.63 +/- 62.17 h). Clinical responses consisted of 4 patients with stable disease and 11 patients with progressive disease, although one patient experienced a 89% decrease in a lymph node mass, and one patient experienced inflammatory symptoms in cutaneous metastases, suggestive of a biological effect of hu3S193. No immune responses (human anti-human antibody) to hu3S193 were observed.

CONCLUSION

Hu3S193 is well tolerated and selectively targets tumors, and the long half-life and biological function in vivo of this antibody makes it an attractive potential therapy for patients with Le(y)-expressing cancers.

Phase I biodistribution and pharmacokinetic study of Lewis Y-targeting immunoconjugate CMD-193 in patients with advanced epithelial cancers

PURPOSE

This phase I study explored the biodistribution and pharmacokinetics of the immunoconjugate CMD-193 [a humanized anti-Lewis Y (Le(y)) antibody conjugated with calicheamicin in patients with advanced cancers expressing the Le(y) antigen.

EXPERIMENTAL DESIGN

The primary objectives were to determine biodistribution and pharmacokinetics of CMD-193. Secondary objectives included response rates and change in tumor metabolism. Patients with progressive, measurable, and Le(y) positive malignancies were eligible for enrollment in one of two dose cohorts, 1.0 and 2.6 mg/m(2). The first cycle was trace labeled with (111)In for biodistribution assessment using gamma camera imaging. Subsequent cycles were administered every 3 weeks up to a maximum of six cycles, depending on toxicity and response. Pharmacokinetic analysis was based on radioassay and ELISA.

RESULTS

Nine patients were enrolled in the study. Biodistribution images showed initial blood pool activity, followed by markedly increased hepatic uptake by day 2, and fast blood clearance in all patients. There was low uptake in tumor in all patients. The overall T(1/2)beta of (111)In-CMD-193 was 102.88 +/- 35.67 hours, with no statistically significant difference between the two dose levels. One patient had a partial metabolic response on (18)F-fluorodeoxyglucose-positron emission tomography ((18)F-FDG PET) after four cycles, but no radiological responses were observed. Myelosuppression and effects on liver function were the most significant adverse effects.

CONCLUSIONS

CMD-193 shows rapid blood clearance and increased hepatic uptake compared with prior studies of the parental antibody hu3S193. These results highlight the importance of biodistribution and pharmacodynamic assessment in early phase studies of new biologics to assist in clinical development.

Generic prescribing for epilepsy. Is it safe?

Generic prescribing for epilepsy remains controversial. This study aimed to ascertain if a change occurred in the incidence of seizures or side-effects when a different pharmaceutical manufacturer's version of the same antiepileptic drug was taken (a 'switch'). Forty general practices with a list size of 350 168 were recruited. They identified 2285 people being treated for epilepsy with either carbamazepine, phenytoin or sodium valproate. A questionnaire was sent to the people with epilepsy. Those who recalled taking a different pharmaceutical manufacturer's supply of the same antiepileptic drug over the last 2 years were interviewed by their practice if they reported a problem with the control of their epilepsy after a 'switch'. One thousand, three hundred and thirty-three (58.8%) people with epilepsy responded: 251 (18.7%) had experienced a 'switch', 27 (10.8%) reported 'validated' problems; 25 (9.9%) reported unproven problems; 22 (8.8%) reported problems, but follow-up was incomplete; 177 (70.5%) reported no problems. This study suggests that money saved by generic prescribing is outweighed by negative health gain for the person with epilepsy, increased work in general practice, and increased social costs.

Epilepsy: patient views on their condition and treatment

To determine how patients with epilepsy feel about their condition, their current medication and their treatment, a mail survey was conducted among a random selection of 800 members of the British Epilepsy Association (BEA). Completed questionnaires were received from 437 members (55% response rate). This high response rate, achieved over a 4-week period, indicates great concern about their condition among the membership sampled. The majority of patients (80%) were adults; 20% were 18 years or younger. Some 72% of patients experienced one or less seizures per month and 52% were employed. Comments from an open-ended question about treatment indicated that respondents would like to see an increase in the provision of services and in the information conveyed (a more interactive communication between the patient and the physician); both issues should improve the emotional support provided by physicians. Positive feelings about medications were reported when seizures were controlled, although unhappiness was expressed with the length of time and varying doses that had to be taken before a 'correct' dosage level was established. Also expressed was a concern about the extent of management and of experimentation with medication left to the patient and care-giver. Opportunities exist for greater communication among physician, patient and care-givers to ease the feeling of frustration, discouragement and isolation seen with a condition which affects 2 to 3% of individuals during their lifetime.

Patient views on primary care services for epilepsy and areas where additional professional knowledge would be welcome

In the past decade there has been increasing interest in the part that general practice can play in the care of people with epilepsy. Primary care services for epilepsy vary from practice to practice. Some studies have suggested that people with epilepsy prefer secondary care services and are not keen for their epilepsy to be managed in general practice, but much of the data were collected in secondary care. This study collected data from various sources about present provision of services, patient satisfaction with services, views about service development, areas where GP knowledge may be improved and whether the site of data collection influenced the results. A questionnaire was piloted, then distributed and collected through branches of the British Epilepsy Association, general practice and secondary care clinics. Data collected were both quantitative and qualitative. One hundred and seventy-eight questionnaires were collected from three sources. The responders were a severe seizure group. Structured care in general practice was uncommon with 54% being seen only when needed. Dose and type of antiepileptic medication was rarely altered in general practice. Information about their condition was given to 44% of the responders by their GP. Sixty-one percent would prefer their epilepsy care to be 'shared' between primary and secondary services. The majority of patients were satisfied with GP services, felt they could easily discuss their epilepsy, but 58% felt they 'rarely' or 'never' received enough information about their condition in general practice. Satisfaction with GP care varied, dependent on where the data were collected. Patients would value more information and more time to discuss the effects of their epilepsy. In conclusion general practice care for epilepsy is still reactive. Patients value more information and more time to discuss implications. The data collection point affects the results; any conclusions about the organisation of epilepsy care should draw data from community patient samples.

Phase I Imaging and Pharmacodynamic Trial of CS-1008 in Patients With Metastatic Colorectal Cancer

PURPOSE

CS-1008 (tigatuzumab) is a humanized, monoclonal immunoglobulin G1 (IgG1) agonistic antibody to human death receptor 5. The purpose of this study was to investigate the impact of CS-1008 dose on the biodistribution, quantitative tumor uptake, and antitumor response in patients with metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Patients with mCRC who had received at least one course of chemotherapy were assigned to one of five dosage cohorts and infused with a weekly dose of CS-1008. Day 1 and day 36 doses were trace-labeled with indium-111 ((111)In), followed by whole-body planar and regional single-photon emission computed tomography (SPECT) imaging at several time points over the course of 10 days.

RESULTS

Nineteen patients were enrolled. (111)In-CS-1008 uptake in tumor was observed in only 12 patients (63%). (111)In-CS-1008 uptake and pharmacokinetics were not affected by dose or repeated drug administration. (111)In-CS-1008 biodistribution showed gradual blood-pool clearance and no abnormal uptake in normal tissue. No anti-CS-1008 antibody development was detected. One patient achieved partial response (3.7 months duration), eight patients had stable disease, and 10 patients had progressive disease. Clinical benefit rate (stable disease + partial response) in patients with (111)In-CS-1008 uptake in tumor was 58% versus 28% in patients with no uptake. An analysis of individual lesions showed that lesions with antibody uptake were one third as likely to progress as those without antibody uptake (P = .07). Death-receptor-5 expression in archived tumor samples did not correlate with (111)In-CS-1008 uptake (P = .5) or tumor response (P = .6).

CONCLUSION

Death-receptor-5 imaging with (111)In-CS-1008 reveals interpatient and intrapatient heterogeneity of uptake in tumor, is not dose dependent, and is predictive of clinical benefit in the treatment of patients who have mCRC.

Correlates of employment history and employability in a British epilepsy sample

This study examined the inter-relationships between employment status, employment experiences, background, educational and epilepsy-related variables in a community sample of 1709 people with epilepsy in England and Wales. A postal questionnaire yielded information which included attitudes to careers advice, experiences with fellow employees and management when in work, experiences of being questioned about epilepsy, and the perceived effect of having epilepsy on employment prospects. In a principal components analysis, a factor of 'employability' was identified that had high loadings for educational qualifications, socioeconomic status and employment history. Good employability was found to be related to perceptions that epilepsy had little or no effect on job prospects, good experiences with work colleagues and management, low seizure severity and good seizure control. Further data analyses which focused on people's actual employment histories confirmed the importance of past experiences in employment, educational qualifications, seizure severity and seizure frequency for distinguishing between groups. The study findings are discussed and, taken together, they imply that quality of medical care, employability and good employment history are interconnected in important ways.

Targeted chemoradiation in metastatic colorectal cancer: a phase I trial of 131I-huA33 with concurrent capecitabine

huA33 is a humanized antibody that targets the A33 antigen, which is highly expressed in intestinal epithelium and more than 95% of human colon cancers but not other normal tissues. Previous studies have shown huA33 can target and be retained in a metastatic tumor for 6 wk but eliminated from normal colonocytes within days. This phase I study used radiolabeled huA33 in combination with capecitabine to target chemoradiation to metastatic colorectal cancer. The primary objective was safety and tolerability of the combination of capecitabine and (131)I-huA33. Pharmacokinetics, biodistribution, immunogenicity, and tumor response were also assessed.

METHODS

Eligibility included measurable metastatic colorectal cancer, adequate hematologic and biochemical function, and informed consent. An outpatient scout (131)I-huA33 dose was followed by a single-therapy infusion 1 wk later, when capecitabine was commenced. Dose escalation occurred over 5 dose levels. Patients were evaluated weekly, with tumor response assessment at the end of the 12-wk trial. Tumor targeting was assessed using a γ camera and SPECT imaging.

RESULTS

Nineteen eligible patients were enrolled. The most frequently observed toxicity included myelosuppression, gastrointestinal symptoms, and asymptomatic hyperbilirubinemia. Biodistribution analysis demonstrated excellent tumor targeting of the known tumor sites, expected transient bowel uptake, but no other normal tissue uptake. (131)I-huA33 demonstrated a mean terminal half-life and serum clearance suited to radioimmunotherapy (T1/2β, 100.24 ± 20.92 h, and clearance, 36.72 ± 8.01 mL/h). The mean total tumor dose was 13.8 ± 7.6 Gy (range, 5.1-26.9 Gy). One patient had a partial response, and 10 patients had stable disease.

CONCLUSION

(131)I-huA33 achieves specific targeting of radiotherapy to colorectal cancer metastases and can be safely combined with chemotherapy, providing an opportunity to deliver chemoradiation specifically to metastatic disease in colorectal cancer patients.

Is Preputioplasty Effective and Acceptable?

Foreskin complaints in childhood, if not manageable conservatively, are usually treated by circumcision. A less radical surgical option, when balanitis xerotica obliterans is absent, is preputioplasty. We sent questionnaires to the parents of 23 boys who had had this procedure and 22 replied.

Mean interval since operation was 20 months (range 3-36). The main indications for surgery had been irretractable foreskin in 9, recurrent balanoposthitis in 10 and ballooning on voiding in 3 and the operation had dealt successfully with these in 7, 7, and 3, respectively. In all but one case the parents were satisfied with the cosmetic result. However, in 8 cases (36%) the parents said they would have preferred circumcision and 3 of the boys had been listed for further surgery.

Preputioplasty is a satisfactory alternative to circumcision in selected cases.

Is preputioplasty effective and acceptable?

Foreskin complaints in childhood, if not manageable conservatively, are usually treated by circumcision. A less radical surgical option, when balanitis xerotica obliterans is absent, is preputioplasty. We sent questionnaires to the parents of 23 boys who had had this procedure and 22 replied. Mean interval since operation was 20 months (range 3-36). The main indications for surgery had been irretractable foreskin in 9, recurrent balanoposthitis in 10 and ballooning on voiding in 3 and the operation had dealt successfully with these in 7, 7, and 3, respectively. In all but one case the parents were satisfied with the cosmetic result. However, in 8 cases (36%) the parents said they would have preferred circumcision and 3 of the boys had been listed for further surgery. Preputioplasty is a satisfactory alternative to circumcision in selected cases.

Single umbilical artery ligation-induced fetal growth retardation: effect on postnatal adaptation

To assess whether prolonged intrauterine stress and resultant fetal growth retardation result in depletion of adrenal catecholamines and alter the adrenergic signal transduction system, we studied newborn sheep after single umbilical artery ligation (SUAL)-induced growth retardation. The animals were delivered at term, and postnatal cardiovascular, pulmonary, endocrine, and metabolic responses were measured. We also evaluated the status of myocardial and pulmonary beta-adrenergic receptor number and function. SUAL caused significant growth retardation but relative preservation of brain and adrenal gland weight and adrenal catecholamine content. Blood pressure, plasma free fatty acid, and glucose responses at birth were blunted in SUAL animals. The plasma epinephrine (Epi) and norepinephrine levels were comparable in both groups for the first 2 h of age. By 4 h, both plasma concentration and plasma appearance rate of Epi were reduced to 40% of control in SUAL animals (P less than 0.05). Neither beta-receptor density, affinity, nor adenylate cyclase activity were altered by SUAL in either cardiac or pulmonary membranes. These results suggest that, rather than overt depletion, there is relative sparing of initial adrenal medullary function that later waned. This response and preservation of the beta-adrenergic signal transduction system may represent partial compensation for the physiological stress induced by SUAL.

Managing epilepsy in general practice: the dissemination and uptake of a free audit package, and collated results from 12 practices in England and Wales

This study aimed to assess the uptake and use by general practitioners of a free epilepsy audit protocol, and describe the care provided by practices which returned completed audits. A protocol for epilepsy audit in general practice was designed and described in the medical press. Practices were invited to reply. Responders were provided with the protocol. A total of 215 practices responded to the articles in the press. Questionnaires asking how they had used the audit protocol were sent to them 18 months later. One hundred and seventy (79%) of the 215 responding practices returned the questionnaires. Forty-seven (28%) had collected some or all of the data. Twenty-two (13%) submitted data of which 12 (7%) matched the original protocol. Aggregated list sizes for these 12 practices was 75689 and 502 (0.66%) patients were being treated. Of these, 60% were seizure free and 11% were having more than one seizure per month. Seventy-one were receiving monotherapy and only two patients were taking more than three drugs. Eighty-eight per cent of patients still having seizures had been seen by their GP for their epilepsy in the last 12 months. In 18% of cases, information on epilepsy lifestyle issues had been given and noted. Offering a free epilepsy audit package can stimulate interest amongst practices in the topic and resulted in 13% collecting and submitting their data for analysis. Practices reported a higher prevalence for epilepsy (0.66%) than in previous studies. The majority of patients with active epilepsy (88%) had been seen by a general practitioner in the last 12 months. Most (71%) were receiving monotherapy, but recording of seizure frequency and provision of information about epilepsy was low.

Meeting the educational needs of general practitioners for epilepsy

Epilepsy care in general practice has been criticized, but what do GPs feel they deal with most and complete satisfactorily? If criticism is justified, education should be useful in improving epilepsy care, but what do general practitioners want to learn and how do they want to learn it? Questionnaires about these issues were sent to randomly chosen general practitioners throughout the United Kingdom. One hundred and twenty-four out of 200 (62%) responded. They were not biased by age, sex, type of practice or previous interest in epilepsy. Drug treatment and regular review were the two areas of care GPs said they dealt with most, but only half felt they dealt with them well. Sixty-six percent wanted to learn more about drug treatment, 46% about lifestyle advice, 45% about non-drug treatment, 44% about diagnosis and only 16% did not want to learn more about any aspect of care. Weekdays and evenings were the preferred times for study. Courses up to one full day away from practices were popular, distance learning and personal education plans were not, except for a group of younger GPs. When attending courses multi-disciplinary lectures rated highly and nearly three-quarters preferred to attend courses where epilepsy was covered in conjunction with other conditions. Future epilepsy education for GPs should recognize these findings if attendance and positive outcomes are to be maximized.

Plasma epinephrine appearance and clearance rates in fetal and newborn sheep

Newborn plasma catecholamine levels are elevated compared to fetal life. Whether this reflects increased catecholamine secretion after birth or decreased clearance is not known. To determine the plasma appearance and clearance rates for catecholamines during the transition to postnatal life, we compared plasma epinephrine appearance and clearance rates in fetal sheep before birth and in newborns after delivery. Plasma epinephrine appearance and clearance rates were measured by radiotracer analysis in eight fetuses at 127 +/- 1 days of gestation and, after cesarean delivery, at 130 +/- 1 days of gestation. There was no difference in plasma epinephrine appearance rate during the fetal (26 +/- 4 ng.kg-1 x min-1) or newborn studies (31 +/- 5 ng.kg-1 x min-1). The fetal plasma epinephrine clearance rate (131 +/- 13 ml.kg-1 x min-1) was significantly higher than newborn plasma epinephrine clearance rate (40 +/- 3 ml.kg-1 x min-1). Thus fetal plasma epinephrine appearance rate is not different from appearance rate in the immediate newborn period when catecholamine levels are higher than during most other physiological circumstances. The increase in circulating catecholamine levels at birth is due in part to a significant decrease in clearance rate. It is likely that removal of the placental contribution to whole body clearance accounts for much of the difference observed in fetal and newborn clearance rates.

Maturational changes in expression of enkephalin peptides in adrenal and extra-adrenal tissue of fetal and adult rabbits

Met-enkephalin immunoreactivity (MET-ENKi), total enkephalin immunoreactivity (TOTAL MET-ENKi) and catecholamines were measured in adrenal and extra-adrenal tissue of fetal, newborn and adult rabbits. Met-enkephalin peptides were detected in adrenal and extra-adrenal tissue by 29 days of gestation. There were progressive increases in TOTAL MET-ENKi in both the adrenal and extra-adrenal tissue during development. In 29-day-old fetuses, MET-ENKi represented 43 and 50% of the peptide content in adrenal and extra-adrenal tissues respectively. By 3 days after birth, MET-ENKi represented only 15 and 7% of the peptide content in the same tissues. In the adult adrenals, 10% of enkephalin peptides were found as MET-ENKi. There were progressive increases in adrenal and extra-adrenal catecholamine content in the fetal and newborn rabbits throughout development. The changes in the ratio of MET-ENKi to TOTAL MET-ENKi peptides suggest differences in posttranslational processing of proenkephalin peptide during maturation. We speculate that enkephalin peptides derived from proenkephalin A are important during fetal and early newborn life and that extra-adrenal tissue may be an important source of these peptides during development.

The visualisation of fingermarks on Pangolin scales using gelatine lifters

Recent media reports document the plight of the Pangolin and its current position as "the most trafficked mammal in the world". They are described by some as scaly anteaters as all species are covered in hard keratinous tissue in the form of overlapping scales acting as a "flexible dermal armour". It is estimated that between 2011 and 2013, 117,000-234,000 pangolins were slaughtered, but the seizures may only represent as little as 10% of the true volume of pangolins being illegally traded. In this paper, methods to visualise fingermarks on Pangolin scales using gelatine lifters is presented. The gelatine lifters provide an easy to use, inexpensive but effective method to help wildlife crime rangers across Africa and Asia to disrupt the trafficking. The gelatine lifting process visualised marks producing clear ridge detail on 52% of the Pangolin scales examined, with a further 30% showing the impression of a finger with limited ridge detail. The paper builds on an initial sociotechnical approach to establishing requirement, then it focuses on the methods and outcomes relating to lifting fingermarks off Pangolin scales using gelatine lifters, providing an evaluation of its use in practice.

A phase I single dose escalation trial of ch806 in patients with advanced tumors expressing the 806 antigen

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Background: Ch806 is a chimeric antibody (mAb) that binds to a unique epitope only exposed on a transitional untethered form of the Epidermal Growth Factor Receptor (EGFR), and the de2–7 EGFR, but not exposed on wtEGFR. Immunohistochemistry (IHC) studies have demonstrated that the 806 antigen is not detected in any normal human tissue, but is highly expressed in a broad range of epithelial cancers, and in gliomas. Preclinial studies have shown that ch806 has potent anti-tumor activity in xenograft models expressing amplified EGFR or de2–7 EGFR, and is internalized into tumor cells. Methods: The primary objective of this first in man study was to determine the toxicity of increasing single doses of c806. The secondary objectives were to characterize the biodistribution, pharmacokinetics (pK) and tumor uptake of In-111 ch806, to determine human antibody responses (HACA), and to document tumour responses to ch806. Patients with advanced or metastatic disease whose tumors expressed the 806 antigen by IHC received a single infusion of 111In-labelled ch806. 111In-ch806 was administered as a single, 1 hour infusion at dose levels of of 5 mg/m2, 10 mg/m2, 20 mg/m2 and 40 mg/m2. Results: 7 patients (1 at 5mg/m2 dose and 2 each at 10, 20 and 40 mg/m2 doses) have been entered into the study: squamous cell lung (2), colorectal (1), squamous cell anus (1), mesothelioma (1), squamous cell larynx (1) and squamous cell skin with lung metastasis (1). Patients had a median age 66 (range 49–75) and median of 1.5 (range 0–4) prior oncological treatment regimens. No significant toxicities were observed. The biodistribution of ch806 showed excellent targeting of tumour sites in all patients. There was no evidence of any normal tissue uptake of ch806. PK analysis showed comparable Cl at all dose levels (mean ± SD: 34.6 ± 5.0 mL/hr), no normal tissue saturable compartment, and dose dependent Cmax and AUC. HACA analysis is ongoing. One patient had a reduction in size of cervical lymphadenopathy on study, and progressive pulmonary disease at study completion. There was 1 patient with SD and 6 with PD at study completion. Conclusion: ch806 was very well tolerated and targeted a wide range of tumour types with no normal tissue uptake, which is markedly different to other mAbs that target wtEGFR.

No significant financial relationships to disclose.

Cardiovascular effects of SKF 104078 in lambs

We studied the effects of SKF 104078 in anesthetized, newborn lambs and compared it to nonspecific alpha-receptor blockade by tolazoline. SKF 104078 infusion decreased pulmonary and systemic arterial pressures in newborn lambs when infused during normoxic ventilation. When infused during hypoxia, SKF 104078 decreased cardiac output and systemic blood pressure without affecting pulmonary pressure. Due to the predominance of systemic effects, the usefulness of SKF 104078 in states of hypoxic pulmonary vasoconstriction is limited.