Clinical considerations for biosimilar antibodies

Biosimilar agents are approximate copies of branded biologic therapies. Since the first biosimilar was authorized in the European Union in 2006, fifteen additional agents have been approved by the European Medicines Agency, including two biosimilar monoclonal antibodies (mAbs). Biosimilar mAbs represent a distinct class given their large molecular size, complex protein structure, and post-translational modifications. While guidelines have been established for the development, approval, and use of biosimilars, further scrutiny and discussion is necessary to fully understand their potential impact on clinical outcomes. This review takes a critical look at the structural complexity of biosimilar mABs, the feasibility of indication extrapolation, the impact of product variability on immunogenicity, the importance of comprehensive pharmacovigilance, and the potential for ongoing pharmacoeconomic impact

Biosimilar agents in oncology/haematology: from approval to practice

The regulation of biosimilars is a process that is still developing. In Europe, guidance regarding the approval and use of biosimilars has evolved with the products under consideration. It is now more than 3 years since the first biosimilar agents in oncology support, erythropoiesis-stimulating agents, were approved in the EU. More recently, biosimilar granulocyte colony-stimulating factors have received marketing approval in Europe. This review considers general issues surrounding the introduction of biosimilars and highlights current specific issues pertinent to their use in clinical practice in oncology. Information on marketing approval, extrapolation, labelling, substitution, immunogenicity and traceability of each biosimilar product is important, especially in oncology where patients are treated in repeated therapy courses, often with complicated protocols, and where biosimilars are not used as a unique therapy for replacement of e.g. growth hormone or insulin. While future developments in the regulation of biosimilars will need to address multiple issues, in the interim physicians should remain aware of the inherent differences between biosimilar and innovator products

Small-molecule inhibitors of the receptor tyrosine kinases : promising tools for targeted cancer therapies

Chemotherapeutic and cytotoxic drugs are widely used in the treatment of cancer. In spite of the improvements in the life quality of patients, their effectiveness is compromised by several disadvantages. This represents a demand for developing new effective strategies with focusing on tumor cells and minimum side effects. Targeted cancer therapies and personalized medicine have been defined as a new type of emerging treatments. Small molecule inhibitors (SMIs) are among the most effective drugs for targeted cancer therapy. The growing number of approved SMIs of receptor tyrosine kinases (RTKs) i.e., tyrosine kinase inhibitors (TKIs) in the clinical oncology imply the increasing attention and application of these therapeutic tools. Most of the current approved RTK–TKIs in preclinical and clinical settings are multi-targeted inhibitors with several side effects. Only a few specific/selective RTK–TKIs have been developed for the treatment of cancer patients. Specific/selective RTK–TKIs have shown less deleterious effects compared to multi-targeted inhibitors. This review intends to highlight the importance of specific/selective TKIs for future development with less side effects and more manageable agents. This article provides an overview of: (1) the characteristics and function of RTKs and TKIs; (2) the recent advances in the improvement of specific/selective RTK–TKIs in preclinical or clinical settings; and (3) emerging RTKs for targeted cancer therapies by TKIs.Felix Mindus foundationPublishe

The survival of patients enrolled in a global direct-to-patient cancer medicine donation program: The Glivec International Patient Assistance Program (GIPAP)

The Glivec International Patient Assistance Program (GIPAP) is a unique direct-to-patient program that provides imatinib (Glivec) at no cost to eligible patients in low- and middle-income countries (LMICs) with chronic myelogenous leukemia (CML) or gastrointestinal stromal tumor (GIST). This paper analyses the output, outcome and impact of the program between 2001 and 2014 using the data collected by the Max Foundation. Method: We extracted data on GIPAP patients’ country of residence, sex, diagnosis, date of enrollment in GIPAP, age at enrollment, case closure date, and reason for closure from The Max Foundation database covering the period 2001 to 2014. We used Kaplan-Meier method to assess the survival rate of patients in GIPAP and used the proportional hazard regression model to estimate the effect of different variables on patients’ survival. Findings: About 63,000 GIPAP patients in 93 countries received over 71 million defined daily doses (DDD) of imatinib between 2001 and 2014. Our analysis showed that GIPAP patients had a 5-year survival rate of 89% which compares favorably to survival in high income countries despite the challenges of delivering cancer care in LMICs. Age at enrollment into the program, sex, duration between diagnosis and enrollment into program, year of enrollment, and patients’ diagnosis (CML vs non-CML) were factors that influenced survival

Overexpression of orphan receptor tyrosine kinase Ror1 as a putative tumor-associated antigen in Iranian patients with acute lymphoblastic leukemia

Receptor tyrosine kinases (RTKs) are a group of enzymes involved in a variety of physiological and pathological processes. The human Ror1 is a member of the RTK family with unknown ligand and biological function. Overexpression of Ror1 has recently been reported in B-cell chronic lymphocytic leukemia. The aim of this study was to explore the expression profile of Ror1 in acute lymphoblastic leukemia (ALL) cells. Therefore, leukemic cells were isolated from the bone marrow and/or peripheral blood (PB) of 57 ALL patients. Immunophenotyping was performed by flow cytometry and mRNA expression was detected by RT-PCR. Overexpression of Ror1 mRNA was detected in 23 of 57 (40) ALL patients. A similar expression pattern was observed in ALL cell lines, with 4 of 12 (33) being positive. Stimulation of normal PB mononuclear cells with pokeweed mitogen and phorbol myristate acetate induced substantially higher Ror1 mRNA expression compared to unstimulated cultured cells. There has been neither a significant association between Ror1 expression and the immunophenotypic profile of the leukemic cells, nor with other clinical or hematological features of the patients. In conclusion, our findings propose Ror1 as a new tumor-associated antigen and a potential tool for targeted immunotherapy and monitoring of minimal residual disease in ALL. Copyright © 2008 S. Karger AG