Lecture 4 Assuring Quality of BMP Flashcards
Compare and Contrast Pharmaceuticals vs Biopharmaceuticals
Pharmaceuticals are:
- smaller
- produced through chemical synthesis
- defined (simpler) and easier to characterize
- relatively heat, pH stable and less prone to microbial contamination
Biologicals:
- large molecules, extracted from living cells/systems
- complex structures, more difficult to characterise (& to copy)
- heat-sensitive and susceptible to microbial contamination
How are traditional biological medicinal products (TBMP) derived?
Historically extracted directly from human and animal tissues
What are biotechnology-derived medicinal products (BDMP)?
Newer biological products produced in living cells , e.g. microbial , mammalian , insect, rodent and plant cells via biotechnology
What are some examples of biotechnology-derived medicinal products (BDMP)?
Examples of BDMP include human insulins, HGH and EPO made via recombinant DNA (rDNA) and monoclonal antibodies made via hybridoma technology.
What are some examples of traditional biological medicinal products (TBMP)?
Examples of TBMP include blood components albumin, plasma, platelets (human) and rabies vaccine (dogs), heparin (pigs) and antivenoms (snakes)
What is biotechnology?
Use of living cells/organisms, or their products to modify human and animal health, mankind and his environment
What are the steps involved in Recombinant DNA technology?
- Transformation (Heat shock –> selection –> cultivation in cell bank)
What are the steps involved in Hybridoma technology?
- Immunization
- Isolate B cells
- Fuse B cells with myeloma cells
- screening and selection (of the hybrid cell line)
- cultivation (clonal expansion)
What are the advantages of Microbial cells over Mammalian cells for use in biotechnology?
- Faster cultivation (relatively straightforward fermentation)
- Relatively safe product
What are the advantages of Mammalian cells over Microbial cells for use in biotechnology?
- No cell disruption (product secreted outside cells)
- Higher yield due to less complicated purification
- More complex proteins with post-translational modifications
What was a key safety concern initially for hybridoma technology?
Possible Contamination of Protein Product with potentially oncogenic Host Cell (Hybridoma) DNA delayed use of Mammalian Cells for many years
Which study report helped enable the use of mammalian cells for biological production?
1987 WHO Study Report
- Concluded No Reason to exclude Continuous (Mammalian) Cell Lines for Biological Production if Purification process can reduce Residual DNA to <10 nanogram per dose
Why is the term biosimilar used instead of generics for biologics that refer from the innovator biologic?
Each biotech derived medicinal product is unique and difficult to replicate identically
What are some key GMP and QA issues in manufacture of biotechnology derived medicinal products?
- Assuring genetic stability (of plasmid and GOI)
- Absence of impurities, endogenous (inherent) viruses and adventitious viruses (introduced during production) and residual DNA (from hybridoma of mammalian cell)
- Assuring quality and yield through consistent manufacturing process
- absence of (biological & chemical) impurities from nutrient media & starting materials
Is it acceptable to introduce small changes to manufacturing processes for biotechnology derived medicinal products?
No. As cell substrates are “living factories”, slight changes to manufacturing processes can have major impact on quality, (safety and efficacy) of product
What are biosimilars?
According to the US FDA, a biosimilar is a biological product which is “ highly similar ” to, and has no clinically significant differences from an existing FDA approved reference product, often the innovator product
What are the comparative studies required to determine the high degree of similarity between biosimilar and reference product?
- Molecular Structure and Potency (Bioactivity)
- Toxicity Study (Non-Clinical/Animal Study)
- Pharmacodynamics (Clinical/Human Study)
- Pharmacokinetics (Clinical/Human Study)
- Immunogenicity (Clinical/Human Study)
In the production of biosimilars, are minor differences in terms of clinically inactive components, e.g. buffers and stabilizers acceptable?
Yes
Why are biosimilars often lower cost than innovator products?
Lower R and D/Regulatory Costs
- 65 - 85% cost
Which PICS GMP Annex helps us in inspection of biotechnology medicinal products?
Annex 2 of PICS GMP guide for Medicinal Products
Annex 2: Manufacture of Biological Products
What are the major steps in the manufacture of biotechnology medicinal product?
(1) Cell Banking
(2) Cell Cultivation
(3) Harvesting
(4) Purification
(5) Viral Clearance (Inactivation/Removal)
(6) Batching and Storage of Bulk Biological API
(7) Formulation, Packaging and Release of Finished Product (injection)
Where does inspection start for biotechnology medicinal product manufacture?
We can start inspection at the cell bank as we would start at the warehouse for a conventional inspection of a pharmaceutical facility
What does the master cell bank (MCB) contain?
- Contains well characterized cells derived from specific cell line, at a specific passage level
- Cells are stored frozen under defined conditions, e.g. liquid nitrogen (-196 degrees Celsius)
What is a working cell bank (WCB) for and what needs to done prior to its use?
- Used to provide “working” cells for manufacturing
- WCB is derived from one or more containers of MCB
- A WCB must be tested before use
- Tests are usually less than those conducted at MCB
What are the types of tests conducted for cell banks?
Tests for:
- Genetic Stability
- Endogenous viruses
- Adventitious viruses
- Residual DNA
How are Adventitious viruses introduced into a cell bank?
During Sampling, cell expansion or transfer from MCB to WCB
Why are some companies outsourcing Testing of Cell banks to Sometimes Outsourced to Specialized Contract Testing Laboratories?
The tests are a highly specialized activity that requires sophisticated equipment, infrastructure and expertise
What is inspected during an inspection of Cell Bank System?
- Documentation of Cell Origin and History (via QC Tests records)
- Management of Cell Banks (MCB and WCB)
- Contract Testing Laboratories
How should the Cell Banks be managed and documented?
- Appropriate storage condition
- SOPs and records for liquid nitrogen replacement
- Stock control/reconciliation of cell vials
- Cross-contamination preventative measures
- Restricted access
- Maintenance and back-up arrangements
What do inspectors look at when inspecting contract test laboratories?
- Availability of comprehensive written contract, clearly showing the Roles and Responsibilities of Contract Acceptor and Giver
What is the difference between “Fermentation” and “Cell Culturing”?
- “Fermentation” used when Microbial Cells e.g. E. coli (Bacteria); S. cerivisiae (Yeast) are cultivated in Fermentor
- “Cell Culturing” used when Mammalian Cells , e.g. CHO Cells, Murine Myeloma Cells are cultivated in Bioreactor