Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 1

Characterisation and comparability:

The role of Reference Standards and Method Standardization

ISCT GRP Workshop, Auckland, 22.4.2013

Lääkealan turvallisuus- ja kehittämiskeskus

Disclaimer: The views expressed in this presentation are those of the speaker and do not represent official opinion of EMA or any of its´ committees. The regulatory aspects are based on EU legislation and guidelines.

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 3

CBMPs

Somatic cell therapy MPs Tissue Engineered MPs Genetically modified cells (both GTMPs and CBMPs)

Manufacturing processes are unique, batch sizes may be small, autologous products, availability of materials for e.g. validation and control may be limited, impact of the storage (frozen vs. non-frozen)

Risks and limitations related to CBMP production and testing are higher than for any other MPs (cell drifting, difficulties of bioassays)

Is characterisation of a new CBMP the same as release assays combined with few additional cell surface markers?

cells scaffolds

signalling molecules

Blood/ nutrient supply

Tissue regeneration

Integrity of

organels

Viability

Gene

expression

Signalling

Proliferation

Differentation

Quality of

proteins

Motility

Apoptosis

Respiration

Energy

Morphology Functionality

Metabolic

activity

- Signalling cell - cell, device – cells - Proliferation vs. differentiation in vitro/in vivo - Structural integrity and functionality of the cells and the device(s) - Biocompatibility, toxicity, biodistribution, stability vs. turnover etc. - Analytical tools available to analyse cells in combination with devices?

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 5

Integrity of

organels

Viability

Gene

expression

Signalling

Proliferation

Differentation

Quality of

proteins

Motility

Apoptosis

Respiration

Energy

Morphology Functionality

Metabolic

activity

Critical parameters of cells?

Critical parameters of most MPs are related to molecular integrity; Critical parameters of cells - should safeguard both structural and functional integrity of the cells -should be able to reflect changes in complex, dynamic and viable entities

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 6

GUIDELINE ON HUMAN CELL-BASED MEDICINAL PRODUCTS EMEA/CHMP/410869/2006

autologous vs allogeneic / cell like or tissue like / immunoactive / proliferative / differentiated

Identity – markers, morphology, cell interactions, metabolism, matrix, scaffold

Cell purity – relevant cells, ratio of viable to non viable

Impurities - product / process – unwanted cells, degradation products,

metabolites / adventitious agents, bioactive reagents

Potency – according to intended function

– required for comparability,consistency and stability Tumourigenicity , Karyology / Genetic Stability, Biocompatibility

Release specifications for final products or intermediates : identity, purity, potency, impurities, sterility, cell viability and total cell number (dose), structural component

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 7

should be based on the intended biological effect which should ideally be related to the clinical response should detect clinically meaningful changes in the product (loss of function, dediffentation etc.) in vitro assays / in vivo assays or assays based on surrogate markers (gene expression profiles, flow cytometric immunoassays etc.) different products, differing assays (e.g. structural analysis for tissue-like products, immunological assays immunotherapeutic products etc.); multiple assays if necessary!

Potency testing

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 8

insufficent knowledge on the active component(s) limited sample size / shelf life (autologous, primary cells) unknown mode of action / lack of appropriate biological atribute structural and functional complexity / multifactorial actions - poor specificity interfering substances / poor parallelism - poor accuracy inappropriate tools – acceptance criteria / specifications too wide non linearity – characterisation under dynamic conditions

Confounding aspects hampering potency testing of CBMPs

Lääkealan turvallisuus- ja kehittämiskeskus 23.4.2010 Paula Salmikangas 9

Correct differentiation

of chondrocytes

De-differentiation

of chondrocytes

Potency of chondrocytes

If a failure detected in the potency testing, how to define the root cause without a reference preparation? should the product still be given to the patient?

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 10

Comparability

if the product or its´ manufacturing process are changed during or after the pivotal clinical studies, comparability of the product before and after the change(s) has to be demonstrated

Several scientific advices given on comparability studies due to e.g.manufacturing changes, upscaling and technology transfer to multiple sites Quality data alone based on extensive characterisation and stability profile are hardly sufficient to demonstrate comparability of cells functional assays! analytical methods have insufficient quantitative power to identify subpotent batches: high probability that supportive non-clinical and clinical studies are required extent and design of additional studies?

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 11

CHO cells, plated under different conditions, exhibit different cellular morphology.

(Bucher Biotech)

Cells easily change when culture conditions are changed; autologous products suffer from inherent variability, use of growth factors, long in vitro cell expansions, difficulties in potency and comparability testing….

Would poor reference materials be better than none at all?

Feasibility of reference materials for CBMPs?

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 12

Legal requirements concerning reference materials 2001/83:

1.2. Identification and assay of active substance(s) (all MPs)

An in vivo or in vitro biological assay shall be obligatory when physico-chemical methods cannot provide adequate information on the quality of the product. Such an assay shall, whenever possible, include reference materials and statistical analysis allowing calculation of confidence limits.

2009/120: 3.3.2.6. Reference materials (SCMPs & TEPs)

“A reference standard, relevant and specific for the active substance and/or the finished product, shall be documented and characterised”

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 13

Guideline on cell-based medicinal products (EMEA/CHMP/410869/2006) The potency assay should be performed by using a specified number of cells and, when possible, quantified against a qualified reference preparation (TEPs)

Guideline on potency testing of immunotherapy MPs for treatment of cancer (EMEA/CHMP/BWP/271475/2006)

5.5 Reference preparation In general, potency assays on biological medicinal products rely heavily on the use of reference preparations with an established potency. Most likely, no international reference preparation will be available for highly specific cell based immunotherapy products and it may be difficult to generate such preparations for autologous products. ‘In-house’ reference materials should be characterised in terms of their composition, purity and biological activity as thoroughly as possible by physicalchemical- biological methods. The in-house reference material should preferably be clinically qualified or shown to be comparable to materials shown to be efficacious in clinical trials.

CBMP guidance

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 14

infections (microbial contamination of starting materials or during processing)

tumourigenicity (cell transformation, integration to genome)

dedifferentation / loss of function of the cells

immunogenicity, rejection

ectopic engraftment of cells to non-target tissues

shedding (genet. modif. CBMPs; germ line, environment)

small sample sizes, short shelf-lives, availability of proper animal models, applicability of analytical methods etc.

Risks vs. limitations of ATMPs

Risk-based approach for all ATMPs http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2013/03/WC500139748.pdf

Lääkealan turvallisuus- ja kehittämiskeskus 8.5.2013 Paula Salmikangas 15

How to identify possible subpotent batches??

Characterisation of a new CMBP should encompass several analytical tools defining structural and functional properties of the product; rather too many available assay than too few

for a combined product, all testing should be done with the final composition

Possibilities for in-house reference materials exist and should be explored and used, whenever possible

Reference cell preparations and small satellite pieces (TEPs) could be grown from reference material side by side each batch

Conclusions

8.5.2013 Paula Salmikangas 16

Thank you for your attention!

(Lagopus lagopus (willow grouse)