Novel vaccines and immunologicals – Beating the super bug
Absynth Biologics has been created with the initial goal of developing immunological prophylaxis and therapy to combat bacterial infections. Absynth’s strategy is to exploit the characterisation of carefully selected novel proteins Staphylococcus aureus (S. aureus)in bacteria as immunological targets.
These novel targets are being developed as prospective vaccine components and for the production of prophylactic or therapeutic monoclonal antibodies (MAbs). The most advanced programmes target S. aureus including its more difficult-to-treat drug-resistant form, methicillin-resistant S. aureus (MRSA).
The market for an MRSA vaccine or therapy is large and growing in the UK and US; hospital acquired infections are an increasing public health concern and are responsible for a rise in the number of hospital deaths.
Worldwide 2 billion people carry some form of S. aureus; up to 53 m (2.7% of carriers) are thought to carry MRSA.
In the US, S. aureus infections:
- cause 13% of the 2m hospitalised infections annually
- representing 260,000 people with an infection of S. aureus
- leading to between 60,000-80,000 fatalities.
Financial and human costs of in-patients with S. aureus infection are greater compared to uninfected patients:
- 3 times the length of hospital stay (14.3 vs 4.5 days)
- 3 times the total charges ($48,824 vs $14,141), and
- 5 times the risk of in-hospital death (11.2% vs 2.3%)
S. aureus is a highly versatile, opportunist pathogen able to cause a wide range of infections including septicaemia, endocarditis and wound abscesses. It is a primary cause of hospital acquired infections and is responsible for thousands of deaths each year.
The threat of the organism is compounded by its ability to gain resistance to antibiotics; methicillin resistant S. aureus (MRSA) is endemic in many UK hospitals.
MRSA are often resistant to many antibiotics and for some strains, the antibiotic vancomycin is the only useful drug. However, vancomycin resistance has now been reported. This alarming finding means that there is a pressing need to develop new treatments to combat S. aureus infections.
In addition, resistance to antibiotics is not confined to hospitals, but is also now emerging in the community. Drug resistance, compounded by the spread of strains, makes this a worldwide problem and “superbugs” such as MRSA pose a significant threat to human health.
For 60 years antibiotics have been the conventional treatment for bacterial infection and the antibiotic market is worth $37bn globally. However, antibiotic resistance is increasing to a number of the “older” products and the cost of treating nosocomial infections reported to be $7bn in the US alone.
New antibiotics are continuing to be developed – i.e. Daptomycin, Linezolid but it is likely that, over time, a similar pattern of resistance will develop and alternative strategies for dealing with MRSA and other “superbugs” are required.
The Absynth Biologics Concept
Historically, the main approaches for producing vaccines involve the use of Intact killed pathogens, live attenuated pathogens or sub-cellular fragments (subunits), alone or conjugated to carrier molecules. Conjugate vaccines now in widespread use for diseases such as meningitis, typhoid and pneumonia. By contrast a similar approach with S. aureus has not produced positive results in clinical studies. Absynth’s distinctive approach to address these issues involves:
- The identification and targeting of multiple bacterial protein antigens that are essential to the organism and have an additive or synergistic effect when used in combination; and
- Also have highly conserved sequences, providing improved strain coverage as well as being the basis for a vaccine platform comprised of homologous antigens in different pathogens; and
- A dual-action mechanism to stimulate the human immune system consisting of (i) direct antibody-mediated inhibition of bacterial growth and (ii) antibody-mediated engagement of the immune system to enhance elimination of the bacteria.
Absynth Biologics was originally founded with investment from Biofusion plc., now part of IP Group plc (www.ipgroupplc.com) , a leading UK intellectual property commercialisation company, listed on the London Stock exchange.