10th European immunogenicity platform open symposium on immunogenicity of biopharmaceuticals

Therapeutic proteins and emerging gene and cell-based therapies are attractive therapeutic tools for addressing unmet medical needs or when earlier conventional treatment approaches failed. However, the development of an immune response directed against therapeutic agents is a significant concern as it occurs in a substantial number of cases across products and indications. The specific anti-drug antibodies that develop can lead to safety adverse events as well as inhibition of drug activity or accelerated clearance, both phenomena resulting in loss of treatment efficacy. The European Immunogenicity Platform (EIP) is a meeting place for experts and newcomers to the immunogenicity field, designed to stimulate discussion amongst scientists across industry and academia, encourage interactions with regulatory agencies and share knowledge and the state-of-the-art of immunogenicity sciences with the broader scientific community. Here we report on the main topics covered during the EIP 10th Open Symposium on Immunogenicity of Biopharmaceuticals held in Lisbon, 26–27 February 2019, and the 1-d training course on practical and regulatory aspects of immunogenicity held ahead of the conference. These main topics included immunogenicity testing, clinical relevance of immunogenicity, immunogenicity prediction, regulatory aspects, tolerance induction as a mean to mitigate immunogenicity and immunogenicity in the context of gene therapy.

Abstract P1-10-01: A randomized, double-blind trial to compare the efficacy and safety of proposed biosimilar pegfilgrastim (LA-EP2006) with reference pegfilgrastim in patients with breast cancer (PROTECT1)

Background: An abbreviated pathway for biological products shown to be biosimilar to the reference product exists in Europe and the US. The randomized PROTECT1 trial compared the efficacy and safety of the proposed biosimilar pegfilgrastim with reference pegfilgrastim.

Methods: In this multinational, prospective, double-blind trial, chemotherapy-naïve women aged ≥18 years with histologically proven breast cancer received up to 6 cycles of (neo)-adjuvant TAC chemotherapy (docetaxel 75 mg/m2, doxorubicin 50 mg/m2, cyclophosphamide 500 mg/m2). Patients were randomized to a single 6 mg SC injection of the proposed biosimilar pegfilgrastim (LA-EP2006) or the reference (Neulasta®) on day 2 of each cycle. Primary endpoint was duration of severe neutropenia (DSN) during Cycle 1, defined as number of consecutive days with an absolute neutrophil count (ANC) <0.5 x 109/L. The study was powered at 90% and had a hierarchical testing procedure utilizing a ±1 day margin to test for equivalence (2-sided 95% confidence interval [CI]) and a subsequent −0.6 day non-inferiority margin (1-sided 97.5% CI) for DSN during Cycle 1. DSN was analyzed with an ANCOVA model adjusted for treatment, chemotherapy, region and baseline ANC. Secondary efficacy assessments were: time to ANC recovery, ANC nadir, incidence of febrile neutropenia, number of days of fever, frequency of infections and mortality due to infection. Safety was assessed at 4 weeks and 6 months after the last pegfilgrastim administration. Immunogenicity was assessed by testing for neutralizing anti-pegfilgrastim antibodies.

Results: A total of 316 patients were randomized and included in the full analysis set (LA-EP2006: n=159; reference: n=157). Baseline demographics were similar in both groups (mean±SD age: LA-EP2006 49.9±9.53, reference 50.5±10.87 years; breast cancer stage II-III: LA-EP2006 n=155 [97.5%], reference n=151 [96.2%]). Mean±SD DSN in Cycle 1 was 0.75±0.88 days with LA-EP2006 and 0.83±0.90 days with reference, with a treatment difference of 0.07 days (95% CI: −0.12, 0.26); LA-EP2006 was both equivalent and non-inferior to the reference. There were no clinically meaningful differences between LA-EP2006 and reference in incidence of febrile neutropenia (3.8% vs 7.0% in Cycle 1, 5.7% vs 7.6% across all cycles), days with fever, depth of ANC nadir in Cycle 1, time to ANC recovery in Cycle 1, or frequency of infections in Cycle 1 and across all cycles. Treatment-emergent adverse events (TEAEs) were similar across groups and consistent with the known safety profile of pegfilgrastim. Most frequently reported TEAEs related to treatment were musculoskeletal and connective tissue disorders (LA-EP2006 4.4%, reference 5.7%). Serious TEAEs were reported in 10.1% of LA-EP2006 and 13.4% of reference patients. No neutralizing anti-pegfilgrastim antibodies were detected.

Conclusions: Proposed biosimilar pegfilgrastim (LA-EP2006) met the primary endpoint demonstrating both equivalence and non-inferiority to the reference. LA-EP2006 and the reference are similar with no clinically meaningful differences regarding efficacy and safety in breast cancer patients receiving (neo)-adjuvant myelosuppressive chemotherapy.

Citation Format: Harbeck N, Zbarskaya I, Lipatov O, Frolova M, Udovitsa D, Topuzov E, Ganea-Motan DE, Nakov R, Singh P, Rudy A, Blackwell K. A randomized, double-blind trial to compare the efficacy and safety of proposed biosimilar pegfilgrastim (LA-EP2006) with reference pegfilgrastim in patients with breast cancer (PROTECT1). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-10-01.

Role of Smac in cephalostatin-induced cell death

Cephalostatin 1 is a natural compound isolated from a marine worm that induces apoptosis in tumor cells via an apoptosome-independent but caspase-9-dependent pathway and through an endoplasmic reticulum stress response that is accompanied by caspase-4 activation. Here, we show that cephalostatin evokes mitochondrial Smac (second mitochondria-derived activator of caspases) but not cytochrome c release in various carcinoma cell lines. We also show that Smac is critically involved in caspase-9 activation as evidenced by gene silencing experiments. Remarkably, caspase-2 appears to be a major target for cephalostatin-induced cytosolic Smac. Using biochemical and genetic inhibition experiments, we demonstrate that caspase-2 participates in the apoptotic machinery induced by cephalostatin. Cephalostatin-activated caspase-2 appears to act as initiator caspase and is not involved in the activation of caspase-9. Importantly, experiments immunoprecipitating PIDD (p53-induced protein with a DD), RAIDD (RIP-associated ICH-1/CED-3-homologous protein with DD) and caspase-2 identify cephalostatin as an experimental drug that induces the formation of the PIDDosome. The bis-steroid cephalostatin proves to be both a helpful tool to investigate apoptotic signaling and a promising chemotherapeutic agent.

Spongistatin 1: a new chemosensitizing marine compound that degrades XIAP

Spongistatin 1 is a new experimental chemotherapeutic agent isolated from marine sponges. Here we show that spongistatin 1 potently induces cell death in patient primary acute leukemic cells with higher efficiency than 8/10 clinically used cytotoxic drugs and prevents long-term survival of leukemic cell lines. Spongistatin 1 triggers caspase-dependent apoptosis in Jurkat T cells by the release of cytochrome c, Smac/DIABLO and Omi/HtrA2. As caspase-9 acts as an initiator caspase and Bcl-2 and Bcl-xL overexpression suppress spongistatin 1-induced apoptosis, cell death is mediated through the mitochondrial apoptosis pathway. Importantly, spongistatin 1 leads to the degradation of the antiapoptotic X-linked inhibitor of apoptosis protein. In apoptosis-resistant leukemic tumor cells overexpressing XIAP, spongistatin 1 effectively causes cell death and potentiates cell death induction by other apoptosis-promoting factors that might be caused by spongistatin 1-mediated degradation of XIAP. Our data show that spongistatin 1 represents a promising novel therapeutic agent for the treatment of leukemic tumor cells especially in the clinically highly relevant situation of chemoresistance due to overexpression of XIAP.

Homocysteine concentrations and vascular complications in patients with type 2 diabetes

OBJECTIVE

Hyperhomocysteinemia is a well known risk factor for the diseases of the cardiovascular system, which seem to be the main cause of increased mortality in patients with type 2 diabetes. The aim of the study was to evaluate the levels of homocysteine in patients with type 2 diabetes in respect to the regimen of diabetes treatment as well as the presence of diabetic complications.

METHODS

The investigation was carried out in the group of 64 patients with type 2 diabetes and in 18 healthy subjects from the control group. Clinical examination and measurements of homocysteine, folic acid, vitamin B12, glycosylated hemoglobin concentration and evaluation of parameters of the lipid metabolism, microalbuminuria and creatinine were done in both groups.

RESULTS

Homocysteine concentration was significantly higher in the group of patients with diabetes in comparison to the control group (p = 0.0007). Diabetic patients had significantly lower concentrations of folic acid (p = 0.028) and HDL cholesterol (p = 0.025) together with higher levels of systolic blood pressure (p = 0.007). In the group of patients with diabetes no differences in homocysteine levels were found in respect to diabetes treatment. Diabetic patients with coronary artery disease had significantly higher homocysteine concentration in comparison to the group with diabetes without history of coronary artery disease (p = 0.0097). Homocysteine levels correlated significantly with incidence of ischaemic heart disease (r = 0.44, p = 0.001) and microalbuminuria (r = 0.26, p = 0.019). Negative correlation was noticed in HDL concentrations (r = -0.30, p = 0.013) and the levels of folic acid (r = -0.30, p = 0.008).

CONCLUSION

Our results suggest that hyperhomocysteinemia in diabetic patients may contribute to the development of chronic complications. The influence of diabetes treatment on Hcy levels requires further observations.

Pulmonary neuroendocrine cells in physiology and pathology

Pulmonary neuroendocrine cells are scant and widespread within the pulmonary epithelium. The function they play is not fully known, more studies are needed to clearly define it. They have been implicated however, as either the culprit or victim of many pulmonary diseases. That is the reason, why so many scientists take interest in the pulmonary neuroendocrine system. This paper reviews current information regarding pulmonary neuroendocrine cells, their origin, morphology, ontogeny, role, neuroendocrine cell markers, dysplasia and hyperplasia of pulmonary neuroendocrine cells in various conditions, diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, typical carcinoid, atypical carcinoid, small-cell lung carcinoma, large-cell neuroendocrine carcinoma and the unusual spectrum of pulmonary neuroendocrine tumours.

Helicobacter pylori vacA genotypes and cagA gene in a series of 383 H. pylori-positive patients

BACKGROUND

Only 10-15% of all patients infected with Helicobacter pylori develop peptic ulcer disease (PUD) or gastric cancer. Apart from immunological factors in the host, virulence determinants of H. pylori such as the vacuolating cytotoxin (VacA) or the cytotoxin-associated protein A (CagA) might represent a predisposition for the development of PUD.

METHODS

We studied antral biopsies of 383 H. pylori-positive patients with peptic ulcer disease (PUD) or other H. pylori-related diseases for H. pylori vacA genotypes and the presence of the cagA gene by PCR.

RESULTS

VacA genotypes and cagA status could be completely determined in 357 (93.2%) of the patients. In 91 (93.8%) of 97 patients with PUD, the vacA s1 genotype (s1m1, 45; s1m2, 46 patients) was present. The vacA s2m2 genotype was found in only 6 (6.2%) of 97 patients with PUD. In contrast, 180 (75.3%) of 239 patients (s1m1, 89; s1m2, 91 patients) without PUD and without gastric malignancies harbored strains with the vacA s1 genotype. The vacA genotype s2m2 was found in 59 (24.7%) of these patients. The presence of the cagA gene was closely associated with the vacA genotype s1 and found in 124 (88.6%) and in 113 (80.7%) of patients with the s1m1 or s1m2 genotypes, respectively, whereas strains with the genotype s2m2 were almost exclusively cagA negative.

CONCLUSION

Most H. pylori strains found in patients with PUD possess the vacA s1 genotype and the cagA gene. Patients with this type of H. pylori strain but without PUD might be at higher risk of developing PUD. In contrast, the risk for PUD might be significantly decreased in those patients who are infected by H. pylori strains with the vacA s2 genotype lacking the cagA gene.

Direct determination of Helicobacter pylori vacA genotypes and cagA gene in gastric biopsies and relationship to gastrointestinal diseases

OBJECTIVE

Our aim was to detect Helicobacter pylori (H. pylori) from gastric biopsies of 248 patients using a novel, polymerase chain reaction (PCR)-based methodology, which simultaneously facilitates the determination of H. pylori vacA genotypes and cagA gene.

METHODS

A simple methodology for sample preparation was established and PCR was performed with primer systems for the 16S rRNA, vacA, and cagA genes, thus circumventing the need to culture H. pylori and to extract DNA from biopsy samples.

RESULTS

Infection with H. pylori was detected in 147 (59.3%) of 248 patients. The vacA signal sequence genotype s1 was present in 104 (81.3%) of 128 H. pylori-positive patients, and 24 (18.8%) patients had the genotype s2. The vacA middle region types m1 and m2 were detected in 46 (35.9%) and 79 (61.7%) patients, respectively. The combinations s1/m2 (43%) and s1/m1 (35.9%) were found more frequently than s2/m2 (18.8%). The cagA gene was detected in 75 (72.1%) of 104 H. pylori-positive biopsies with the vacA genotype s1. All 24 biopsies with the type s2 were cagA negative. Strains of the type vacA s1 were found in 97% of H. pylori-positive patients with peptic ulcer disease and were associated with the presence of the cagA gene, whereas 96% of the strains of the type vacA s2 were detected in patients who only had nonulcer dyspepsia.

CONCLUSIONS

Using a novel PCR-based methodology, H. pylori 16S rRNA gene, vacA genotypes, and cagA gene can now be rapidly detected directly in gastric biopsies with high accuracy. These data demonstrate that infection with H. pylori strains of the vacA s1 genotype and the cagA gene are more likely to result in peptic ulcer disease. Determination of vacA genotypes and cagA gene may contribute to the potential clinical identification of patients at different levels of risk.

An occupational therapy program with the chronic care patient

The following is an example of what the occupational therapists at the Allan Memorial Institute in Montreal have done to accommodate the changing psychiatric population at the hospital. Over the past few years it seemed that certain of our programmes, being too high level, were no longer suitable for the more chronic type patient, being admitted. Thus, a re-examination of attitudes towards treatment was necessary as was the establishment of programmes with a different orientation. In doing this, the focus changed from former techniques such as projective art to a concentration on more reality oriented programmes for this group. The two programmes described are examples of this.