Anti-neoplastic biosimilars--the same rules as for cytotoxic generics cannot be applied.

Biopharmaceuticals are complex protein molecule drugs produced by living organisms. Biopharmaceuticals as anti-neoplastic monoclonal antibodies are a major breakthrough in oncology. When the patent of innovator biopharmaceuticals expires, copies will be introduced. These copies are after approval by European Medicines Agency (EMA) within EU called biosimilars and have their own regulatory pathways which differ from the chemical generics approval process. The main reason is that identical copies of chemical molecules via chemical syntheses can be produced but copies of innovator biopharmaceuticals will only be similar. An extensive comparability exercise has to be carried out between the reference product and the biosimilar before approval. However, still there might be differences between the innovator anti-neoplastic monoclonal antibody and the biosimilar anti-neoplastic antibody which cannot be detected until extended clinical studies have been carried out. Moreover, all indications for an anti-neoplastic biosimilar antibody may not have been tested for at the time of approval but extrapolated based on the indications of the reference monoclonal antibody. The limited information on biosimilar anti-neoplastic monoclonal antibodies at approval may still be justified taking into account that the aim is to reduce price. However, the risk-benefit ratio for biosimilar anti-neoplastic monoclonal antibodies should be carefully evaluated, considering that anti-neoplastic monoclonal antibody therapy has a curative intent, price reduction so far within EU of biosimilars is modest and that in the end only part of the total costs for cancer health care is related to biopharmaceuticals.

Monoclonal antibodies against ROR1 induce apoptosis of chronic lymphocytic leukemia (CLL) cells.

ROR1 is a receptor tyrosine kinase (RTK) recently identified to be overexpressed at the gene and protein levels in chronic lymphocytic leukemia (CLL). Monoclonal antibodies (MAbs) against RTKs have been successfully applied for therapy of solid tumors. We generated five MAbs against the Ig (n = 1), cysteine-rich (CRD) (n = 2) and kringle (KNG) (n = 2) domains, respectively, of the extracellular part of ROR1. All CLL patients (n = 20) expressed ROR1 on the surface of the leukemic cells. A significantly higher frequency of ROR1 expression was found in patients with progressive versus non-progressive disease, and in those with unmutated versus mutated IgVH genes. All five MAbs alone induced apoptosis in the absence of complement or added effector cells (Annexin-V and MTT, as well as cleavage of poly-(ADP ribose)-polymerase, caspase-8 and caspase-9) of CLL cells but not of normal B cells. Most effective were MAbs against CRD and KNG, significantly superior to rituximab (P < 0.005). Cross-linking of anti-ROR1 MAbs using the F(ab')(2) fragments of anti-Fc antibodies significantly augmented apoptosis. Two of the MAbs induced complement-dependent cytotoxicity (CDC) similar to that of rituximab and one anti-ROR1 MAb (KNG) (IgG1) showed killing activity by antibody-dependent cellular cytotoxicity. The identified ROR1 epitopes may provide a basis for generating human ROR1 MAbs for therapy.

Cancer vaccines for non-small-cell lung cancer.

Lung cancer is globally the second most common form of cancer in both men and women and the single largest cause of cancer-related mortality in the world. It is a disease with poor prognosis and the survival statistics have scarcely improved since historical times. The advent of targeted therapies has caused an incremental increase in survival figures. Nevertheless, significant progress in treatment outcomes need to be achieved before any perceptible improvement in overall survival of lung cancer patients becomes evident. The use of active-specific immunotherapy or cancer vaccines for the treatment of lung cancer is still in its infancy. Nevertheless several cancer vaccines have demonstrated clinical effects and improvements in overall survival in phase II and phase III trials and several more clinical trials are currently ongoing. This review summarizes the recent developments in NSCLC vaccines.

Generation of a dendritic cell-based vaccine in chronic lymphocytic leukaemia using CliniMACS platform for large-scale production.

We previously demonstrated that dendritic cells (DC) that have endocytosed apoptotic bodies of autologous leukemic cells (Apo-DC) can boost antileukemic T-cell responses. In this study, we report a description of the production procedure and product specification of the Apo-DC vaccine preparations for clinical use. Enriched populations of CD14+ monocytic precursors and CD19+ leukaemic cells were obtained using CliniMACS technology from a single leukapheresis product. Apoptotic bodies were obtained by irradiating (5 Gy) CD19+ selected B cells. DC were generated ex vivo by culturing monocytes with granulocyte macrophage colony-stimulating factor and interleukin-4. Following coculture with apoptotic bodies, DCs were matured with tumour necrosis factor-alpha. The mean percentage of CD14+ cells in the peripheral blood as well as in the leukapheresis product of the patients (n = 10) was approximately 2% (range, 0.8-3.3). Immunomagnetic selection using the CD14 reagent yielded a CD14+ population that was 91 +/- 2.2% (mean +/- SEM) pure. Immunomagnetic selection of CD19 expressing cells yielded a population that was 100 +/- 0.03% pure. Cell viability immediately after selection was 97% and 98% after 7 days of culture. The Apo-DC cellular vaccine product showed a mature phenotype, with a high rate of endocytosis (84%) of apoptotic leukemic B-cells. In conclusion, despite significant variability in the circulating monocyte frequency of the chronic lymphocytic leukaemia patients, our method permitted the production of a DC vaccine with high reproducibility and conforming with recommended quality standards.

Development of a dendritic cell-based vaccine for chronic lymphocytic leukemia.

Evidence for the existence of CLL-specific antigens recognized by the immune system can be gathered from the observation that many patients display monoclonal or oligoclonal expansions and skewed repertoire of T cells. In vitro functional studies have shown that tumor-specific T-cells are able to lyse the leukemic cells. Antileukemic cellular immunity may be boosted in vivo using dendritic cell-based immunotherapy. Our preclinical studies provide evidence that DC that had endocytosed apoptotic CLL cells (Apo-DC) were superior to fusion hybrids, tumor lysate or RNA in eliciting antileukemic T-cell responses in vitro. We have validated a method for enriching the small number of monocyte precursors present in the peripheral blood of CLL patients and utilize them for generating individualized, Apo-DC cellular vaccines. In most cases, a minimum of 50 x 10(6) Apo-DC could be generated, beginning with immunomagnetically enriched monocytes from a single leukapheresis product containing at least 1% CD14+ cells. Cryopreservation and thawing did not affect the phenotype or the T cell stimulatory function of Apo-DC. A phase I/II, open label clinical trial examining the feasibility, safety and immunogenicity of Apo-DC vaccination has been initiated. CLL patients receive 10(7) Apo-DC for at least five immunizations and monitored clinically and immunologically for 52 weeks. Three cohorts are accrued stepwise. Cohort I receives Apo-DC alone; Cohort II: Apo-DC+ repeated doses of low-dose GM-CSF; Cohort III: low-dose cyclophosphamide followed by Apo-DC + GM-CSF.

Idiotype vaccination in patients with myeloma reduced circulating myeloma cells (CMC).

BACKGROUND: Circulating myeloma cells (CMC), exhibiting the same immunoglobulin heavy-chain gene rearrangements as the plasma cells, are part of the myeloma clone. In this study, we evaluated the effect of idiotype (Id) vaccination on CMC. PATIENTS AND METHODS: Eleven patients were immunized with the autologous Id in combinations with granulocyte-macrophage colony-stimulating factor and interleukin 12, and followed for CMC by quantitative real-time allele-specific PCR. Id-specific T cells were monitored by proliferation assay, enzyme-linked immunospot (interferon-gamma) assay, and quantitative real-time PCR for cytokines. Regulatory T (T(reg)) cells were analyzed by flow cytometry. RESULTS: CMC were detected in 9 of 11 patients at start of vaccination. In four patients, CMC declined and two had a complete molecular remission. Further two patients had stable levels of CMC during follow-up, while in three patients CMC progressively increased. Six patients had a vaccine-induced Id-specific T-cell response. A significant correlation was observed between reduced/stable levels of CMC and the Id-specific T cells (P < 0.02). The frequency of T(reg) cells was decreased in immune responders, but increased in immune nonresponders (P < 0.05). No significant change in the serum M-protein concentration was, however, observed in any patient. CONCLUSION: Id vaccination reduced CMC, which correlated with vaccine-induced Id-specific T cells. Further studies are warranted to analyze the clinical significance of CMC and clinical effects of Id vaccination.

The challenge of biosimilars.

BACKGROUND: The purpose of this report was to review issues associated with the introduction of alternative versions of biosimilars used in the oncology setting. DESIGN: Data were obtained by searches of MEDLINE, PubMed, references from relevant English-language articles, and guidelines from the European Medicines Agency. RESULTS: When biosimilars are approved in EU, they will be considered 'comparable' to the reference product, but this does not ensure therapeutic equivalence. Inherent differences between biosimilars may produce dissimilarities in clinical efficacy, safety, and immunogenicity. Switching biosimilars should be considered a change in clinical management. Regulatory guidelines have been established for some biosimilar categories but, because of the limited clinical experience with biosimilars at approval, pharmacovigilance programs will be important to establish clinical databases. Guidelines also provide a mechanism for the extrapolation of clinical indications (approved indications for which the biosimilar has not been studied). This may be of concern where differences in biological activity can result in adverse outcomes or when safety is paramount (e.g. stem cell mobilization in healthy donors). These issues should be addressed in biosimilar labeling. CONCLUSIONS: Biosimilars should provide cost savings and greater accessibility to biopharmaceuticals. A thorough knowledge surrounding biosimilars will ensure the appropriate use of biopharmaceuticals.

Pre-clinical evaluation of a CEA DNA prime/protein boost vaccination strategy against colorectal cancer.

In preparation for a clinical trial in patients diagnosed with colorectal cancer, a vaccination strategy targeting the carcinoembryonic antigen (CEA) was evaluated in mice using a GMP-produced plasmid DNA vaccine, CEA66, encoding a truncated form of the tumour-associated antigen, CEA. The GMP-produced CEA DNA vaccine was also evaluated for toxicity. Repeated intradermal administration of the GMP-produced vaccine using a novel needle-free jet injection device (Biojector) induced robust CD4 and CD8 T-cell responses in mice, and did not result in any vaccine-related toxicity. In a heterologous DNA prime/protein boost setting, cellular immune responses were of higher magnitude in animals primed with CEA66 DNA than in animals receiving repeated doses of recombinant CEA protein. These responses were further enhanced if recombinant murine granulocyte-macrophage colony-stimulating factor was given as an adjuvant prior to vaccination. In contrast to repeated administration of recombinant CEA protein as a single modality vaccine, the heterologous CEA66 DNA prime/rCEA boost vaccination strategy resulted in a qualitatively broader immune response, and supports clinical testing of this vaccination regimen in humans.

NK-cell and T-cell functions in patients with breast cancer: effects of surgery and adjuvant chemo- and radiotherapy.

Breast cancer is globally the most common malignancy in women. Her2-targeted monoclonal antibodies are established treatment modalities, and vaccines are in late-stage clinical testing in patients with breast cancer and known to promote tumour-killing through mechanisms like antibody-dependent cellular cytotoxicity. It is therefore increasingly important to study immunological consequences of conventional treatment strategies. In this study, functional tests and four-colour flow cytometry were used to detect natural killer (NK)-cell functions and receptors as well as T-cell signal transduction molecules and intracellular cytokines in preoperative breast cancer patients, and patients who had received adjuvant radiotherapy or adjuvant combined chemo-radiotherapy as well as in age-matched healthy controls. The absolute number of NK cells, the density of NK receptors as well as in vitro quantitation of functional NK cytotoxicity were significantly higher in preoperative patients than the post-treatments group and controls. A similar pattern was seen with regard to T-cell signalling molecules, and preoperative patients produced significantly higher amounts of cytokines in NK and T cells compared to other groups. The results indicate that functions of NK and T cells are well preserved before surgery but decrease following adjuvant therapy, which may speak in favour of early rather than late use of immunotherapeutic agents such as trastuzumab that may depend on intact immune effector functions.

Generation of DC-based vaccine for therapy of B-CLL patients. Comparison of two methods for enriching monocytic precursors.

BACKGROUND: The generation of Ag-loaded DC under good manufacturing practice (GMP) conditions is logistically challenging and further compounded when the starting precursors need to be purified from B-CLL patients who have overwhelming numbers of circulating B-CLL cells and decreased numbers of monocytes. METHODS: We have previously demonstrated that DC with endocytosed B-CLL apoptotic bodies are powerful stimulators of anti-leukemic T cells. In this study we compared counterflow elutriation and immunomagnetic separation for enriching monocyte precursors, and evaluated the feasibility of generating DC from B-CLL patients and the effects of cryopreservation. RESULTS: Monocyte yield from a single leukapheresis product of a B-CLL patient varied from 1 x 108 to 10 x 108 total cells, from which 40-200 x 106 mature DC could be produced. Adequate numbers of monocytes could not be enriched from one patient with 0.2% monocytes in the leukapheresis product, and the target of 50 x 106 DC was barely achieved in another patient with 0.9% monocytes in the pheresed cells. These results suggested that successful production of DC is dependent on a minimum frequency of 1% CD14(+) monocytes in the leukapheresis product. Cryopreservation of tumor cell-loaded DC yielded a recovery rate of 86+/-4.4% upon thawing, with a total viability of 90+/-2.8%. Most importantly, cryopreserved Ag-loaded DC retained their morphology, phenotype and function. DISCUSSION: The results demonstrate that adequate numbers of functional DC required for clinical therapy can be generated from patients who have >1% of CD14(+) monocytes in the leukapheresis product. Moreover, Ag-loaded DC can be cryopreserved and recovered without significant change in phenotype or function.

Cancer initiatives in developing countries.

The coming decades will bring dramatic increases in morbidity and mortality from cancer in the developing world. The burden of cancer is increasing globally, with an expected 20 million new cases per year in 2020, half of which will be in low- and middle-income countries. Despite an already overwhelming burden of health problems, developing countries must somehow address this cancer pandemic and their alarming share of cancer illness. Many large-scale and innovative worldwide initiatives have been launched in the fight against cancer. These programs represent colossal efforts to expand resources for health education among people and healthcare workers in developing countries and to increase awareness of cancer prevention. Many novel evidence-based and culturally-relevant programs are being implemented for screening and early prevention of common cancers. Several key initiatives are supporting clinical research, guideline development, oncology training, and appropriate technology transfer, such as access to electronic medical literature. Treatment programs are expanding access and quality of radiologic and pharmacologic therapies for cancer. These initiatives represent an unprecedented level of and cooperation among international agencies, governmental and nongovernmental organizations, international foundations, scientific societies, local institutions, and industry. This review examines the scope of need in response to the increasing burden of cancer in the developing world and major initiatives that have been created to respond to these needs.