Date: 2012-09-11
Type of information:
phase: preclinical data
Announcement:
Company: Pro Bono Bio (UK)
Product: long-acting blood factors VIIa, VIII and IX
Action mechanism:
Disease: hemophilia A
Therapeutic area: Hematologic diseases - Genetic diseases - Rare diseases
Country: USA
Trial details:
Latest
news: Pro Bono Bio has announced 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.
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 vivo trials 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.
