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Press Release

Pro Bono Bio announces the successful development of subcutaneous and long- acting blood factors VIIa, VIII and IX for the treatment of haemophilia.

Subcutaneous blood factors expected to revolutionise the treatment paradigm of haemophiliac patients worldwide

Pro Bono Bio Group plc (“PBB”), the international healthcare group, announces the successful conclusion of a series of pre-clinical trials in haemophiliac subjects conducted with the world’s first long acting blood Factors VIIa, VIII and IX capable of subcutaneous administration. The results of these trials are of great importance as these novel long-acting, subcutaneous blood factors are expected to revolutionise the treatment paradigm for haemophilia sufferers worldwide. The availability of PBB’s subcutaneous blood factors would make self-administration by patients at home much easier leading to a significant improvement in treatment compliance and reduction in healthcare system costs by avoiding the need for regular IV infusions.

Key findings from the 8 trials with 6 products conducted at the University of Alabama were:

– PBB’s current subcutaneous form of FVIIa achieved up to 3 days of haemostatic cover providing the prospect of sustained prophylactic treatment for haemophilia A patients who suffer an immune response to FVIII meaning that FVIII is no longer a viable therapy for them.

– PBB’s current intravenous form of Factor VIIa achieved a 12x extension of haemostasis over current commercially available products. This means it could offer significant advantages in trauma applications in hospitals where haemostatic cover can be maintained for the duration of long operations and post-operation, without the current need for multiple administrations and related complications.

– PBB’s subcutaneous form of Factor VIII for haemophilia A achieved a circulating dose level of 20% of the intravenous version and also maintained haemostasis for 72 hours, meaning that it is already suitable for twice-weekly dosing and will be able to be administered at higher subcutaneous doses enabling once weekly dosing or better.

– PBB’s subcutaneous form of FIX for haemophilia B maintained haemostasis for 10 days meaning that it is already suitable for dosing less frequently than once per week.

– PBB expects to optimise these products so that each one will provide haemostatic cover for at least a week and possibly two weeks from a single subcutaneous injection (with circulating blood factor maximum dose levels (“Cmax”) in line with the Malmo Protocol).

Following these successful trials PBB now has 6 blood factor products under development of which 3 can be administered subcutaneously and 3 by intravenous (“IV”) injection. Each of these blood factor products has proven efficacy in a sophisticated combination of in vivotrials in naturally haemophiliac subjects and in vitro assays. PBB’s novel improved blood factors utilise the epitope-cloaking property of PEG to prevent the products from being rapidly detected and destroyed by the patient’s own immune system before the product has had a chance to fulfil its therapeutic potential. This property has already been demonstrated by PBB in a haemophilia B dog. Work is underway to demonstrate that PBB’s other blood factor products are similarly “immune-silent”.

PBB intends to optimise these products, confident that effective prophylactic cover will now be possible with each of these blood factors via a once-a-week regimen of shallow subcutaneous injections.

Professor Ted Tuddenham, emeritus Professor of Haemophilia at University College London and former Director of the Haemophilia Centre at the Royal Free Hospital, a pioneer in the development of gene therapy treatments for haemophilia commented “I consider these products to be a vital breakthrough by PBB as the availability of subcutaneous and long acting blood factors will dramatically improve the quality of life and treatment regimes for haemophilia sufferers. There is a clear and present need for these products, which in the longer term, will continue to augment potential gene therapy options.”

John Mayo, CEO of PBB said, “This is great news. These new, improved blood factors have the potential to revolutionise the quality of life for haemophilia sufferers. These new products also have huge commercial potential. It is medically, morally and commercially important that these products get to market as quickly as possible.”

About Ascension Healthcare plc

Ascension Healthcare plc is a clinical-stage biopharmaceutical company focused on developing and commercialising innovative therapies for the treatment of haemophilia and osteoarthritis. The Company has three products in clinical development for the treatment of haemophilia A and also a range of internationally marketed products for osteoarthritis sufferers. For more information please visit:

For more information contact

Ascension Healthcare plc
Biresh Roy, Chief Executive Officer

[email protected] / +44 (0)20 7291 5400

Consilium Strategic Communications
(European Media and Investor Enquiries)
Lindsey Neville, Ashley Tapp

Tel: +44 (0)20 3709 5700 / [email protected]