Monoclonal antibodies [autosaved]

MONOCLONAL ANTIBODIES

1. Monoclonal antibodies RESIDENT: Fariha Fatima MODERATOR: Dr. Mohammad Tariq Salman

2. ANTIBODIES Derived from different B Lymphocytes cell lines POLYCLONAL. MONOCLONAL . Derived from a single B cell clone Batch to Batch variation affecting Ab reactivity & titre mAb offer Reproducible, Predictable & Potentially inexhaustible supply of Ab with exquisite specificity Enable the development of secure immunoassay systems. NOT Powerful tools for clinical diagnostic tests 4

3. The idea of a " magic bullet " was first proposed by Paul Ehrlich who at the beginning of the 20th century postulated that if a compound could be made to selectively target a disease-causing organism, then a toxin for that organism could be delivered along with the agent of selectivity. Discovery 5

4. Classification of Monoclonal antibodies: First generation monoclonal antibodies Second generation monoclonal antibodies

5. Nomenclature

6. Georges Köhler César Milstein , and Niels Kaj Jerne in 1975 who shared the Nobel Prize in Physiology or Medicine in 1984 for the discovery hybridoma technology 14

7. Large scale production of Mabs : It involves establishing the hybridoma cell bank with cells that are free of adventitious agents such as viruses and mycoplasma that have stability in continuous culture for antibody production rate and cell viability and do not have unusual or expensive media requirements.

8. Cell ,cell debris ,lipids, clotted materials are first removed by filtration. Charged impurities such nucleic acids and endotoxins separated by ion exchange chromatography. PURIFICATION TECHNIQUES

9. Antibody Type Target Indication Abciximab Chimeric Inhibition of glycoprotein IIb /III a Cardiovascular disease Basiliximab Chimeric IL 2R α receptor(CD25) Transplant rejection Cetuximab Chimeric Epidermal growth factor receptor Colorectal cancer,head and neck cancer Infliximab Chimeric Inhibition of TNF α signalling Several autoimmune disorders Rituximab Chimeric CD20 Non Hodgkin’s lymphoma Ibritumomab tiuxetan Murine CD20 Non Hodgkin’s lymphoma Muromonab-CD3 Murine T cell CD3 receptor Transplant rejection FDA APPROVED THERAPEUTIC MONOCLONAL ANTIBODIES

10. Antibody Type Target Indication Tositumomab Murine CD20 Non Hodgkin’s lymphoma Alemtuzumab Humanized CD52 Chronic lymphocytic leukemia Bevacizumab Humanized Vascular endothelial growth factor(VEGF) Colorectal cancer, age related macular degeneration Certolizumab pegol Humanized Inhibition of TNF- α signalling Crohn’s disease Daclizumab Humanized IL-2R α receptor(CD25) Transplant rejection Eculizumab Humanized Complement system protein C5 Paroxysmal nocturnal hemoglobinuria Efalizumab Humanized CD11a Psoriasis

11. Antibody Type Target Indication Gemtuzumab Humanized CD33 Acute myelogenous leukemia Natalizumab Humanized α -4 integrin Multiple sclerosis , crohn’s disease Omalizumab Humanized IG-E Mainly allergy related asthma Palivizumab Humanized An epitope of RSVF protein Respiratory syncytial virus Ranibizumab Humanized VEGF-A Macular degeneration Trastuzumab Humanized ErbB2 Breast cancer

12. Antibody Type Target Indication Adalimumab Human Inhibition of TNF- α signalling Several autoimmune disorders Panitumumab Human Epidermal growth factor receptor Colorectal cancer

13. Drug (brand name) Sponsor Properties Indications Ramucirumab ( Cyramza ) Eli Lilly VEGFR2 antagonist Gastric cancer Siltuximab ( Sylvant ) Janssen Biotech IL-6-specific antibody Multicentric Castleman's disease Vedolizumab ( Entyvio ) Takeda Integrin-receptor antagonist Ulcerative colitis and Crohn's disease Pembrolizumab ( Keytruda ) Merck & Co. PD1-specific antibody Metastatic melanoma Blinatumomab ( Blincyto ) Amgen CD19- and CD3-bispecific antibody B-ALL Nivolumab ( Opdivo ) Bristol-Myers Squibb PD1 inhibitor Unresectable or metastatic melanoma 2014 FDA drug approvals

14. Selected late-stage drugs to watch in 2015 Drug name Sponsors Properties Indication Event due in 2015 Secukinumab Novartis IL-17-specific antibody Psoriasis PDUFA decision in January Evolocumab Amgen PCSK9-specific antibody Hypercholesterolaemia PDUFA decision by September Alirocumab Sanofi/ Regeneron PCSK9-specific antibody Hypercholesterolaemia PDUFA decision Ocrelizumab Roche CD20-specific antibody Multiple sclerosis Top-line Phase III data

15. TYPES OF Mabs that are used in treatment: Naked MAbs : These are without any drug or radioactive material attached to them. They attach themselves to specific Ag on cells, eg . Cancer cells.

16. Trastuzumab :for advanced breast cancer Rituximab : for B cell non-Hodgkin’s lymphoma Cituximab :for advanced colorectal cancer Bevacizumab :for metastatic colorectal cancer Alemtuzumab :for B cell chronic lymphocytic leukemia

17. Conjugated Mabs : They can be used to deliver radionuclides , toxins or cytotoxic drugs to a specific tissue or malignant cell population. These are attached to drugs, toxins or radioactive atoms. They are also referred to “tagged” “labelled” or “loaded” antibodies.

18. Ibritumomab tiuxetin : radiolabelled Mab to treat B cell non-Hodgkin’s lymphoma. Tositumomab : radiolabelled Mab for non-Hodgkin’s lymphoma Gemtuzumab ozogamicin ( M ylotarg ): immunotoxin Mab for AML

19. Blocking or steric hindrance of the function of target antigen i.e., T-lymphocytes, B lymphocytes, tumour necrosis factor-a ( TNFa ) and interleukin (IL) which are capable of transducing intracellular signals . Cytotoxicity to the cell expressing target AG by ADCC or CDC. MECHANISM OF ACTION OF Mabs :

20. Inhibition of growth factors: Epidermal growth factor receptor (EGFR) is a cell surface receptor involved in regulation of cell proliferation and survival. Also new vessels grow to feed the cancer cells through this factor. These factors can be inhibited to arrest growth of cancer cells e.g., cetuximab act as EGFR inhibitor.

21. pharmacokinetics Mabs are used by intravascular route. They have small volume of distribution and limited tissue penetration. They remain in circulation from 2days to 2 weeks. Hour long infusions require a hospital environment and are often associated with mild to very severe side effects.

22. Side effects: M ore common side effects Allergic reactions, such as hives or itching Flu-like symptoms, including chills, fatigue, fever, and muscle aches and pains Nausea Diarrhea Skin rashes

23. Rare ---- more serious side effects Infusion reactions. Severe allergy-like reactions can occur and, in very few cases, lead to death Dangerously low blood cell counts. Decreased red blood cells, white blood cells and platelets Cardiac complications Certain monoclonal antibodies may cause heart failure and a small risk of MI Bleeding. Some of the monoclonal antibody drugs are designed to stop cancer from forming new blood vessels. There have been reports that these medications can cause bleeding

24. Diagnostic Applications Biosensors & Microarrays Therapeutic Applications Cancer , Transplant rejection, Infectious diseases Clinical Applications Purification of drugs , Imaging the target Future Applications Fight against Bioterrorism APPLICATIONS

25. When monoclonal antibody attaches to cancer cell : Make the cancer cell more visible to the immune system Rituximab drug attaches to specific protein CD20 found on B cells makes cell more visible to immune system Block growth signals Cetuximab attaches to growth factor receptors , blocking its signal and suppress cancer growth MONOCLONAL ANTIBODIES IN CANCER TREATMENT

26. Stop new blood vessel from forming Bevacizumab blocks growth signal which attract blood vessels then tumor shrinks. Deliver radiation to cancer cells By combining radioactive particle with monoclonal antibodies, radiation are deliver to cancer cells only , cancer cell dies.

27. RADIOIMMUNOTHERAPY Involves the use of radioactively conjugated Murine antibodies against cellular antigens Ex; Tositumomab ----- non- Hodgkins lymphoma.

28. conclusion Monoclonal antibodies are new biological agents that have good clinical effects and an extended choice in the treatment spectrum to the patients who were not responding to the existent treatments. New therapeutic approaches are rapidly emerging and further studies may help in designing more specific MAbs that would spare the normal tissue, have less adverse effects and improve the patient’s quality of life.