Immunogenicity assay development and validation for biological therapy as exemplified by ustekinumab.

Introduction of biotherapeutics has been a major milestone in the treatment of different chronic diseases. Nevertheless, the immune system can recognize the administered biological as non-self and respond with generation of anti-drug antibodies (ADA), including neutralizing ADA (nADA). Immunogenic responses may result in altered drug dynamics and kinetics leading to changes in safety and efficacy. However, there are several challenges with standard techniques for immunogenicity testing. Ustekinumab (UST), used in different inflammatory diseases, is a therapeutic antibody directed against the shared p40 subunit of interleukin (IL)-12 and IL-23, interfering in the pathogenically crucial T helper type 1 (Th1)/Th17 pathway. We established and validated different approaches for detection and quantitation of UST, UST-specific ADA and nADA. Addressing the obstacle of complex formation of UST with nADA, we developed an acidification assay to approach the total amount of nADA. Validated methods were based on surface plasmon resonance spectroscopy (SPR), enzyme-linked immunosorbent assay (ELISA) and a cell-based approach to characterize neutralizing capacity of nADA. Parameters assessed were determination and quantitation limits, linearity, range, precision, accuracy and selectivity. Quantitation of ADA and UST was feasible at lower concentrations using ELISA, whereas SPR showed a wider linear range for determination of ADA and UST. Accuracy, precision and linearity for quantitation were comparable using ELISA, SPR and the cell-based approach. All validated parameters fulfill the requirements of regulatory agencies. A combination of the testing approaches could address the increasing demand of precision medicine as it can be suitable for capturing the whole spectrum of immunogenicity and is transferable to other biologicals.

Reirradiation plus EGFR inhibition in locally recurrent and unresectable head and neck cancer: final results from a single institution.

PURPOSE: For some patients with recurrent, unresectable, and previously irradiated head and neck squamous cell carcinoma (HNSCC), reirradiation (re-RT) may be a curative option. Chemotherapy with epidermal growth factor receptor (EGFR) inhibition is established as palliative management. This retrospective single-institutional study investigates feasibility, toxicity, and outcome of reirradiation (re-RT) combined with EGFR blockade for these patients. PATIENTS AND METHODS: Between June 2008 and June 2012, 23 patients with inoperable and previously irradiated HNSCC were reirradiated. Concomitant EGFR blockade (cetuximab) was given initially at 400 mg/m2 two days prior to re-RT and weekly (250 mg/m2) thereafter. PET/CT imaging was fused with planning CT in 8 patients. RESULTS: One patient died of anaphylactic shock during the first cetuximab administration; two discontinued treatment on their own request. In all, 20 patients completed re-RT (50.4-66.6 Gy) and received cetuximab as prescribed. Grade 3 acute side effects were documented for dermatitis (35%), dysphagia (30%), acneiform rash (30%), and mucositis (15%). The 1-year overall survival rate was 34.8% Median overall and progression-free survival times were 9 and 4.3 months, respectively. A multivariable analysis using the Cox regression model showed significant positive impact of acneiform rash (hazard ratio [HR] 0.1531, 95% confidence interval [CI] 0.0383-0.6111), while a period from first radiation to re-RT longer than 120 months negatively (HR 0.1633, 95% CI 0.0305-0.8734) influenced patient survival. CONCLUSION: re-RT with concurrent cetuximab was feasible. Compared to platinum-based chemotherapy with fluorouracil and cetuximab, this therapeutic approach did not demonstrate survival benefit. Prolonged intervals from first treatment to re-RT seem to be unfavorable.

Feasibility of 6-month maintenance cetuximab after adjuvant concurrent chemoradiation plus cetuximab in squamous cell carcinoma of the head and neck.

BACKGROUND: Close resection margins < 5 mm (CM) or extra capsular extent at the lymph nodes (ECE) impair the prognosis of patients with squamous cell cancer of the head and neck (SCCHN) scheduled for adjuvant radiochemotherapy. We conducted a multicenter phase II study to investigate toxicity and efficacy of additional cetuximab administered concomitantly and as maintenance for the duration of 6 months following adjuvant radiochemotherapy., Ppreliminary results on feasibility and acute toxicity on skin and mucosa are presented in this article. METHODS: Patients with SCCHN following CM resection or with ECE were eligible for the study. In all, 61.6 Gy (1.8/2.0/2.2 Gy, days 1-36) were administered using an integrated boost intensity-modulated radiotherapy (IMRT) technique. Cisplatin (20 mg/m(2), days 1-5 and days 29-33) and 5-fluorouracil (5-FU) as continuous infusion (600 mg/m(2), days 1-5 + days 29-33) were given concurrently. Cetuximab was started 7 days prior to radiochemotherapy at 400 mg/m(2) followed by weekly doses of 250 mg/m(2). Maintenance cetuximab began after radiochemotherapy at 500 mg/m(2) every 2 weeks for 6 months. RESULTS: Of the 55 patients (46 male, 9 female, mean age 55.6, range 29-70 years) who finished radiochemotherapy, 50 were evaluable for acute toxicity concerning grade III/IV toxicities of skin and mucosa. Grade 3-4 (CTC 3.0) mucositis, radiation dermatitis, and skin reactions outside the radiation portals were documented for 46, 28, and 14 % of patients, respectively. One toxic death occurred (peritonitis at day 57). Cetuximab was terminated in 5 patients due to allergic reactions after the first application. In addition, 22 % of patients discontinued cetuximab within the last 2 weeks or at the end of radiochemotherapy. Of patients embarking on maintenance treatment, 80 % were still on cetuximab at 3 months and 63 % at 5 months. Concurrent and maintenance treatment with cetuximab could be administered as scheduled in 48 % of patients. CONCLUSION: Adjuvant radiochemotherapy with concomitant and maintenance cetuximab is feasible and acute toxicities are within the expected range. Compliance within the first 3-5 months is moderate.

[Heart and lungs : cardinal symptom dyspnea]. / Herz und Lunge : Leitsymptom Dyspnoe.

Dyspnea is one of the major clinical symptoms which patients report to general practitioners, internists, cardiologists and hospitals. In this review article we discuss the evidence of medical history, laboratory procedures and diagnostic investigations to approach patients with acute or chronic dyspnea and try to structure this complex symptom dyspnea to reach the etiology of the underlying disease.

Biopsy-derived oral keratinocytes - A model to potentially test for oral mucosa radiation sensitivity.

Purpose: To establish stable in vitro growth of keratinocytes from very small biopsy specimens and successfully apply new test systems to determine their radiosensitivity. Materials and Methods: Oral mucosa biopsies (diameter: 1.7 mm) from 15 subjects were immobilized with custom-made cups onto culture plates. Outgrowing cells were tested for cytokeratin 5/14 and Ki67, expanded, radiated at different doses, and seeded onto circumscribed areas before being allowed to spread centrifugally. In this newly developed spreading assay, cell-covered areas were measured by image analysis. For statistical analysis, a linear mixed regression model was used; additionally, results were correlated to the radiation dose applied. Colony forming efficiency (CFE) was used to validate the results. DNA damage repair was analysed by gammaH2AX and 53BP1 foci quantification using immunofluorescence microscopy 24 h and 96 h after irradiation. Results: Stable keratinocyte growth continued for up to 7 weeks in 14 biopsies. Cells spread reliably from an initial 16.6 mm2 up to a median of 119.2 mm2 (range: 54.4-290). Radiated cells spread to only 100.7 mm2 (2 Gy; range: 55.3-266.7); 73.2 mm2 (4 Gy; 15-240.4); 47 mm2 (6 Gy; 2-111.9), and 22.7 mm2 (8 Gy; 0-80). Similarly, CFE decreased from 0.223 (0 Gy) to 0.0028 (8 Gy). Using an individual donor as a random factor, cell spread correlated with CFE, where radiation dose was the main driver (decrease by 0.50, adjusted for area). Upon irradiation with 6 Gy, radiation-induced DNA damage was increased after 24 h in all samples, and even after 96 h in 5 out of 7 samples, as detected by a higher number of gammaH2AX/53BP1 foci in irradiated cells (mean 3.7 for 24 h; mean 0.6 for 96 h). Conclusion: In vitro propagation of keratinocytes derived from a small biopsy is feasible. Radiation impairs cellular migration and proliferation, and the newly described spreading assay allows ranking for cellular radioresistance. The keratinocyte model also supports classical functional assays such as clonogenic survival and DNA double strand repair. The clinical relevance awaits upcoming investigations.

Phase III randomized trial of amifostine as a radioprotector in head and neck cancer.

PURPOSE: Radiotherapy for head and neck cancer causes acute and chronic xerostomia and acute mucositis. Amifositine and its active metabolite, WR-1065, accumulate with high concentrations in the salivary glands. This randomized trial evaluated whether amifostine could ameliorate these side effects without compromising the effectiveness of radiotherapy in these patients. PATIENTS AND METHODS: Patients with previously untreated head and neck squamous cell carcinoma were eligible. Primary end points included the incidence of grade > or =2 acute xerostomia, grade > or =3 acute mucositis, and grade > or =2 late xerostomia and were based on the worst toxicity reported. Amifostine was administered (200 mg/m(2) intravenous) daily 15 to 30 minutes before irradiation. Radiotherapy was given once daily (1.8 to 2.0 Gy) to doses of 50 to 70 Gy. Whole saliva production was quantitated preradiotherapy and regularly during follow-up. Patients evaluated their symptoms through a questionnaire during and after treatment. Local-regional control was the primary antitumor efficacy end point. RESULTS: Nausea, vomiting, hypotension, and allergic reactions were the most common side effects. Fifty-three percent of the patients receiving amifostine had at least one episode of nausea and/or vomiting, but it only occurred with 233 (5%) of 4,314 doses. Amifostine reduced grade > or =2 acute xerostomia from 78% to 51% (P<.0001) and chronic xerostomia grade > or = 2 from 57% to 34% (P=.002). Median saliva production was greater with amifostine (0.26 g v 0.10 g, P=.04). Amifostine did not reduce mucositis. With and without amifostine, 2-year local-regional control, disease-free survival, and overall survival were 58% versus 63%, 53% versus 57%, and 71% versus 66%, respectively. CONCLUSION: Amifostine reduced acute and chronic xerostomia. Antitumor treatment efficacy was preserved.

A proof of concept trial of the anti-EGFR antibody mixture Sym004 in patients with squamous cell carcinoma of the head and neck.

PURPOSE: The purpose of the trial was to assess the efficacy and tolerability of Sym004, a novel 1:1 mixture of two chimeric monoclonal antibodies (992 and 1024) targeting non-overlapping epitopes of the anti-epidermal growth factor receptor (EGFR), in patients with squamous cell carcinoma of the head and neck (SCCHN). METHODS: Incurable, recurrent and/or metastatic SCCHN patients with acquired resistance to anti-EGFR monoclonal antibody-containing treatment received weekly infusions of 12 mg/kg Sym004 until disease progression or unacceptable toxicity. RESULTS: Among the 26 patients treated with Sym004, the proportion of patients alive without disease progression at 6 months was 12 % (95 % CI 1-39 %). The median duration of progression-free survival was 82 days (95 % CI 41-140 days). Of 19 patients evaluable for response, eight showed a decrease in the sum of the largest diameter in their target lesions (median 11 %; range 7-27 %). The best overall response was stable disease in 13 patients (50 %). Paired biopsies showed a significant down-regulation of EGFR in both skin and tumors following exposure to Sym004. All patients had EGFR-related adverse events, including grade 3 skin toxicities and grade ≥3 hypomagnesemia reported in 13 (50 %) and 10 (38 %) of 26 patients, respectively. One event fulfilling the protocol-defined criteria for infusion-related reactions (grade 2) was reported. No anti-drug antibodies were detected. CONCLUSIONS: The marked EGFR down-regulation shown in target tissues supports the proposed mechanism of action of Sym004. This trial revealed modest anti-tumor activity of Sym004 in extensively pretreated advanced SCCHN patients.

Structural deviations in a bovine low expression lysozyme-encoding gene active in tissues other than stomach.

Lysozyme-encoding genes (Lys) constitute a gene-family in ruminants. While several of these genes are highly expressed in stomach (sLys), few other copies are weakly expressed in other tissues, notably in polymorphnuclear granulocytes and macrophages (mLys). Searching an understanding for these grossly different levels of expression, we isolated the bovine variant of the gene being expressed in granulocytes and characterized it by sequencing, together with its promoter. Spanning about 9 kb of genomic DNA, the gene is found to be segmented into four exons, in common with all other Lys, as known from vertebrates. Sequence homologies between all bovine sLys-variants exceeds 70% over much of the entire coding sequence and promoter region. This indicates (i) that bovine lysozymes expressed either in stomach or granulocyte originate from a common ancestral gene and (ii) also excludes the possibility that the observed weak expression of the mLys gene is due to major structural rearrangements within the promoter segment. However, primer extension analysis based on RNA isolated from kidney locates the transcription startpoint (tsp of that gene) 44 nt further upstream than observed in both, bovine stomach lysozyme RNA or any of the homologous genes in mice and man. The observed weak expression of this bovine mLys gene appears to be a consequence of both the presence of an extra ATG codon in the extended 5'-UTR, and a severe down mutation of the ancestral TATA-box which is only partially compensated for by the presence of another mutation further upstream resulting in a weak substitute promoter sequence.

A sensitive screening method of detecting anti-granulocyte antibodies employing radiolabeled staphylococcal protein A.

We describe an improved method of detecting anti-granulocyte antibodies utilizing radiolabeled staphylococcal protein A (SPA). The results of this SPA assay were compared to data obtained with leukoagglutination tests and granulocyte indirect immunofluorescence techniques. We have shown that the SPA assay is highly sensitive and reproducible. In addition, absorption studies confirmed that the assay is specific for granulocytes. The SPA assay is performed in microtiter plates, and requires significantly fewer granulocytes and less test sera than previously described techniques. Also, we have shown that granulocytes prepared for this assay can be separated and stored for up to 48 h. Therefore, the SPA assay described herein is particularly useful for screening of sera and is one of the most sensitive assays available for detecting anti-granulocyte antibodies.

Blood hemoglobin level may affect radiosensitivity-preliminary results on acutely reacting normal tissues.

PURPOSE: To evaluate the influence of blood hemoglobin concentration on the radiosensitivity of acutely reacting normal tissues. METHODS AND MATERIALS: Weekly scores (EORTC/RTOG criteria) for acute reactions of skin and mucosa are available for 60 patients with cancer of the head and neck undergoing a standard conventional radiotherapy. The prognostic significance of blood hemoglobin levels on the development of acute reactions is studied by multivariate analysis (Cox Proportional Hazards Model). Further, the incidence and the time to development of these reactions is looked at in cohorts of patients with different mean blood hemoglobin concentrations during radiotherapy. Patients are therefore classified into a "severely anemic group" (hemoglobin < 11.0 g/100 mL), and into a cohort with a blood hemoglobin value equal or above 11.0 g/100 mL. RESULTS: Normal tissue scoring and monitoring of blood hemoglobin levels allows for a detailed analysis of possible correlations. A decrease in the mean blood hemoglobin value of 1 g/100 mL predicts a reduced risk to develop a skin reaction of Grade 2 or 3 (RR = 0.9; p = 0.08; RR = 0.8; p = 0.26, respectively) or a mucosa reaction of Grade 3 (RR = 0.8; p = 0.16), independent from the radiation dose, the treatment time and from previous surgery within the radiation volume (multivariate analysis). Likewise, patients with severe anemia develop grade 3 mucositis or dermatitis less often (0%; 13%) as compared to those with blood hemoglobin concentrations equal or above 11.0 g/100 mL (21%; 19%). Skin and mucosa reactions further tend to occur later in the course of radiation. The observations are not statistically significant and possible reasons will be discussed. CONCLUSIONS: A decreased blood hemoglobin concentration may-perhaps by an impaired tissue oxygenation-reduce the radiosensitivity of normal tissue such as skin and mucosa. However, the data is preliminary and needs further confirmation.

Protective effect of amifostine on dental health after radiotherapy of the head and neck.

PURPOSE: The cytoprotective agent amifostine has been shown to reduce the radiation-induced acute and chronic xerostomia in head and neck cancer patients. The purpose of this study was to evaluate whether or not amifostine also reduces the incidence of dental caries associated with the radiation-induced xerostomia. METHODS AND MATERIALS: The dental status before and 1 year after radiotherapy was retrospectively compared in 35 unselected patients treated as part of the prospective randomized and multicenter open-label Phase III study (WR-38) at the University Hospitals of Heidelberg, Freiburg, and Erlangen. The WR-38 study compared radiotherapy in head and neck cancer with and without concomitant administration of amifostine. RESULTS: Patient and treatment characteristics (particularly the radiation dose and percentage of parotids included in the treatment volume) were equally distributed between the patients who received (n = 17) or did not receive (n = 18) amifostine. Fifteen patients of the amifostine group showed no deterioration of the dental status 1 year after radiotherapy as compared to 7 patients who did not receive the cytoprotector (p = 0. 015, two-tailed Fisher exact test). CONCLUSION: Our data suggest a protective effect of amifostine on the dental health after radiotherapy of the head and neck. The dental status should be used as a primary endpoint in future studies on amifostine.

Alteration of radiation-induced hematotoxicity by amifostine.

PURPOSE: To investigate whether amifostine can reduce radiation hematotoxicity. PATIENTS AND METHODS: Seventy-three patients undergoing radiotherapy for squamous cell carcinoma of the head and neck at the university clinics of Freiburg, Heidelberg, and Erlangen were evaluated. All received 60 Gy (50-70 Gy) at 5 x 2 Gy fractions per week employing standard techniques. Thirty-five were randomized to receive 200 mg/m(2) amifostine i.v. 30 min before radiation; 38 served as control patients. Blood counts (total n = 501) were determined before, during, and while completing radiotherapy. Changes of leukocyte, platelet, and hemoglobin levels were determined and compared using the t test. RESULTS: The blood hemoglobin level and the platelet count were not affected by irradiation, for either the amifostine-treated or control patients. Similarly, the leukocyte counts of amifostine-treated patients did not change during irradiation. However, control patients experienced a decrease in leukocyte count from 8.1 x 10(3)/mm(3) to 5.8 x 10(3)/mm(3) (difference: 2.3 x 10(3)/mm(3)). This seems to be line specific: Whereas amifostine does not affect lymphocyte count, a radiation-induced decrease of neutrophil granulocytes seems to be prevented. CONCLUSION: Amifostine protects from radiation hematotoxicity, particularly affecting the granulocytopoiesis. These data confirm results from our former study.

Visual detection of granulocyte surface antigens using the avidin-biotin complex.

A visual test for detection of granulocyte surface markers using the avidin-biotin complex (ABC) has been developed. That this assay is highly specific, reproducible, and sensitive was determined by studying the expression of HLA antigens on granulocytes with monoclonal antibodies. Further, using granulocyte specific alloantisera, the results of the ABC test compared well to data from leukoagglutination assays and indirect immunofluorescence tests. The assay is particularly advantageous in that granulocytes can be stored, only small amounts of cells and sera are needed, and heterogeneous cell populations can easily be studied.

Epithelial cells in the peripheral blood of patients with cancer of the head and neck: incidence, detection and possible clinical significance.

In this study amplification of cytokeratin-19 mRNA by Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect circulating tumor cells in the peripheral blood of patients with cancer of the head and neck before, during and after radiation therapy. Detection of cytokeratin-19-positive cells coincided with local failure, distant metastasis and anemia.

Erythropoietin for patients undergoing radiotherapy: a pilot study.

BACKGROUND AND PURPOSE: To evaluate the feasibility and efficacy of using recombinant human erythropoietin (rhEPO) to correct decreased hemoglobin levels in patients undergoing radiotherapy and to get an estimate of its influence on the efficacy of radiotherapy. MATERIALS AND METHODS: Fifty patients with cancer of the head and neck and the pelvis were randomized before radiotherapy to different rhEPO treatments (none, 3 x 150 U/kg per week i.v., 3 x 300 U/kg per week i.v. and 3 x 150 U/kg per week s.c.). Hematological parameters were evaluated weekly and the locoregional tumor control rates were determined in 38 patients with head and neck cancer. RESULTS: rhEPO-treated patients showed a significant increase in their hemoglobin values (0.7 g/100 ml per week). The rhEPO response was comparable for patients with cancer of the head and neck and the pelvis. A delayed recovery was seen when iron deficiency or impaired iron mobilization was present. No serious toxicity was observed. Locoregional tumor control was improved, although not statistically significantly, in those head and neck cancer patients who experienced a rapid rise of hemoglobin. CONCLUSIONS: Low hemoglobin levels can be safely and quickly corrected with rhEPO. This may improve the effectiveness of radiotherapy.

[Cyclophosphamide-induced pneumonitis]. / Cyclophosphamid-induzierte Pneumonitis.

Pneumotoxicity of cyclophosphamide is a rare complication of chemotherapy with this drug. 28 cases have so far been reported in world literature. We add one case in whom lung changes had appeared subacutely, after a single dose of cyclophosphamide, and were reversed by corticoids.

Promoting independence in older persons through the internet.

New communication technologies provide hope for promoting independence in older persons. Today the Internet provides opportunities to socialize with others, participate in educational and spiritual activities, and assist with some of the instrumental activities of daily living. This is important in terms of quality of life for older persons as well as reducing expenditures for long-term care. This article discusses the growth in use of the Internet by the elderly and evaluates its ability to meet both various general needs of the population as well as needs specific to older persons.

How do older netcitizens compare with their younger counterparts?

The Internet is modifying the lives of people around the world. Although many talk about the democratization of knowledge and information, differences remain among users as older netcitizens are under-represented and less involved. We use national and representative U.S. data, the Current Population Survey, to show age-based differences. We complement our analysis with web-based data, the Georgia Tech World Wide Web User Surveys, to show Internet characteristics and trends by age for netcitizens. Results show that older users compose a lower share of Internet users than that of the total U.S. population; however, once they join the ranks of avid Internet users, older netcitizens are similar to their younger counterparts.

Rapid EPA and DHA incorporation and reduced PGE2 levels after one week intervention with a medical food in cancer patients receiving radiotherapy, a randomized trial.

BACKGROUND & AIMS: In cancer patients, metabolic alterations, reduced immune competence and anti-cancer treatment can increase the risk of infections. A rapid-acting nutritional intervention might reduce this risk and support overall treatment. The present study investigated whether one week of intervention with a specific medical food led to fatty acid incorporation and functional immunological changes. METHODS: In a randomized, double-blind study, 38 cancer patients receiving radiotherapy consumed daily for one week 400 ml of specific medical food, which is high in protein and leucine, and enriched with fish oil and specific oligosaccharides (Active group), or iso-caloric/iso-nitrogenous product (Control group). Blood samples were taken at day 0 (baseline) and day 7. RESULTS: After one week of intervention, the incorporation of EPA and DHA in white blood cells was significantly higher in the Active group (2.6% and 2.6% of total fatty acids) compared to the Control group (1.0% and 2.2% of total fatty acids) (p < 0.001 and p < 0.05). Serum PGE2 levels decreased in the Active group and increased in the Control group (p < 0.01). No differences were observed on cytokine production in LPS-stimulated whole blood cultures. CONCLUSIONS: In cancer patients receiving radiotherapy, nutritional intervention with a specific medical food rapidly increased the percentage EPA and DHA in white blood cell phospholipids and reduced serum levels of the inflammatory mediator PGE2 within one week. CLINICAL REGISTRATION NUMBER: NTR2121.