Monoclonal antibody (mAb) therapeutics are one of the fastest growing sectors in the pharmaceutical industry and have already established themselves as frontline therapies in oncology.

1. Dr Andrew G Watts
Associate Professor of Medicinal Chemistry
Department of Pharmacy and Pharmacology
University of Bath
October 2014

2. 2
Monoclonal Antibodies
Functional Improvements at SPC
Shelf Life Limits

3. Introduction
3
Monoclonal antibody (mAb) therapeutics are one of the fastest
growing sectors in the pharmaceutical industry and have already
established themselves as frontline therapies in oncology.
These drugs are often assigned short shelf lives once prepared for
administration, typically 24 to 48 hours.
However, SPC’s for some of these drugs recommend they be used
immediately following preparation.

4. Aim
4
To evaluate the physical, chemical and functional stability of
several mAb therapeutics used in oncology.
- Pertuzumab
- Rituximab
- Trastuzumab
- (Infliximab)
Compare the (quality) characteristics of these drugs immediately
after preparation with those at the limit of their SPC assigned shelf
life.

5. Methods
5
Physical/Chemical/Functional analysis of each antibody was
performed using:
• visual inspection
• SDS-page
• pH
• SE-HPLC,
• circular dichroism (VT-CD)
• dynamic light scattering (DLS)
• LC-MS
• Flowcam imaging (particle counting)
• Functional activity (tailored assay)
Each antibody was evaluated immediately following preparation as
well as at its SPC designated shelf life.

6. Results - Pertuzumab
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Sub-visible particles Functional activity

7. Methods
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‘Flowcam’ imaging (sub-visible particle counting)
micro-air bubble
silicone oil
aggregated protein
Quantification and characterisation of sub-visible particles
Flow rate: 0.15 ml/min, efficiency: 30.2%, cell: FC100 100 µm x 2000 µm

8. Methods
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Functional activity – Cell based assay
7.7 Biological activity
Assessment of biological properties constitutes an essential step in establishing
understanding of the stability profile under specific conditions. The technique should be
relevant to the specific biological activity that enables the product to achieve its defined
biological effect.

9. Results - Rituximab
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Sub-visible particles Functional activity

10. Results - Trastuzumab
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Sub-visible particles Functional activity

11. Results - Infliximab
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Sub-visible particles Functional activity

12. Degradation Pathways
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13. Dilution Process
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Dilution
Preparation (reconstitution and dilution):
- Rapid change in the chemical micro-environment of the drug
- Dilution of A results in a dynamic mixture of B, C, D, E and F.

14. Summary
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- Multiple stability studies on numerous monoclonal antibodies
have been performed.
- Higher levels of sub-visible particles and lower levels of functional
activity are observed immediately following preparation, as
compared to the product at the end of SPC assigned shelf-life.
- Dilution of the drug into its ready-to-use form dramatically
changes the micro-environment around the API.
- Physical changes that occur are dynamic and will reach an
equilibrium over time. This has been observed to result in lower
particle numbers and improved functional activity.

15. Research team
Dr
Richard
Parry
• Principal
Scientist
• Functional
Activity
Terry
Chapman
Dr Monika
Ali Khan
Physical Stab
Dr Andy
Watts
• Scientific
Lead
• Chemical
Stability
Maria
Connolly
• Programme
Lead
• Usability

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