The Challenge
Respiratory syncytial virus (RSV) is one of the single most important causes of lower respiratory tract infection (LRTI) in infants and young children worldwide and can cause LRTI in elderly and immunocompromised patients; it is associated with significant morbidity and mortality in these populations.
However, RSV is recognised as a significant cause of respiratory illness in all age groups and there are no effective licensed therapies generally available. Novel correlates of protection are being explored and developing vaccine correlates can assist to bridging other populations. Healthy participants human challenge models will play a major role in the development process.
RSV Human Challenge Models
Healthy participants 18-55 year old
Older Adults aged 60-75 years old
Conducted a number of human RSV challenge studies for a range of customers:
- Currently, the only RSV challenge model commercially available
- Healthy participant model utilised across multiple studies with vaccines and antivirals directed towards RSV
- RSV challenge model available in Older Adults (60-75) – targets population associated with significant unmet need in RSV
As the industry leader in conducting human viral challenge studies, we have developed a large Virobase, of clinical data paired with virological data, host genetics and immunology combined with an extensive biorepository of blood and respiratory samples. This “Virometrics” resource, in conjunction with our unique insight into the host response to viral disease, allows us to tailor study designs to each IMP.
"Congratulations Team!! Well done and thank you all for your incredible efforts"
US Biotech client
Vaccines
Conceptual Challenges:
- Testing proof of concept in the target population (pediatrics or elderly)
- No clear product development pathway
- Correlates of infection are poorly understood
- Lack of fully translatable immunogenicity animal models
Our Human Challenge Models: Towards a deeper understanding
- Healthy adult model enables fast efficient proof of concept demonstration and safety in disease model before moving to at risk populations in field trials
- Elderly (60+) model, enables demonstration of proof of concept in target population with weakened immunity
- For vaccines, both options facilitate efficient investigation of known and novel correlates of vaccine protective effect
Antivirals/Treatments
Conceptual Challenges:
- Testing proof of concept in the target population (pediatrics or elderly)
- Correlates of infection are poorly understood
- Lack of fully translatable immunogenicity animal models
Our Human Challenge Models: Towards a deeper understanding
Study design matched to investigational product mechanism of actions.
- Optimisation of treatment timing
- Time-dependent measurements of biomarkers
- Triggered-dosing options (time or virological)
- Controlled strain exposure
- Consistent placebo response
- Efficient resistance monitoring
Immunomodulators
Conceptual Challenges:
- Limited RSV immunomodulators in development
- Limited focus on adult/elderly populations
Our Human Challenge Models: Towards a deeper understanding
- Well controlled quarantine environments
- Baseline well established prior to infection
- Appropriate for both prophylaxis and treatment
- Flexible dosing and timing
- Establish safety & efficacy to impact infected subjects host response
- Investigate and demonstrate target engagement
- Controlled combination-treatment with drug and standard of care
Related Resources
Explore our blogs and resources on Virus & Bacteria Production & Characterisation for Human Challenge Trials, covering GMP manufacturing and scientific characterisation approaches used to develop safe, infectious challenge agents for high-fidelity clinical studies.
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