Dr Bruce Roser, Founder and Chairman of Stablepharma Ltd, throughout his long career has had a vision to remove our current dependence on the cold chain by reformulating existing approved vaccines, so that they are thermostable, in other words, fridge-free. He has worked tirelessly and written many scientific papers and patents on his work around the remarkable stabilising activity of trehalose glasses on vaccines and other biologicals.
A recent publication in Vaccine (Elsevier) scientific journal highlighted the data demonstrating that Stablpharma’s fridge-free, single-dose, thermostable vaccine (STVX-01) maintained full potency after at least 10 months at 45℃. https://stablepharma.com/publications/
Dr Bruce along with Nick Child, Vice President & Co Founder of Stablepharma Ltd have taken the company from a ‘two man show’ to an international team of over 35, based in London, Cambridge and Madrid (R&D Centre, Spain). “It has been an incredible journey over the years, with a lot of ups and downs. I suppose things really started to move in the right direction in 1985 when I first patented the remarkable stabilising effect of trehalose on many different materials in “Protection of Proteins and the Like”, (Patent GB8517352A).
Over Dr Bruces’ career as a physician and scientist he registered 49 patents and set up Anglia Research Foundation at Anglia Ruskin University in Cambridge and subsequently founded Cambridge Biostability Ltd.
I asked Dr Bruce what was the one thing that kept him on course over the years, which ultimately helped him achieve his vision of proving his thermostable technology in a real pharmaceutical vaccine.
“Over more years than I care to count, I have been working on the ability of trehalose to stabilise at high temperatures, and for years in storage, many drugs and vaccines that previously required refrigeration. Throughout that time I have tried repeatedly to interest major manufacturers to adopt the technology but to little effect. Although there are now over 25 drugs on the market containing trehalose as a stabiliser, manufacturers seem to remain convinced that trehalose is simply a slight improvement over sucrose, as an excipient sugar, and they apparently remain ignorant of the qualitative improvement in storage capability that the extreme chemical inertness and stability of the trehalose molecule confers on stabilising glasses made from it.
“I have recently published a compilation of many of the chemical properties that establish why trehalose is so vastly superior as a stabiliser and enabler of room temperature drugs and vaccines, ‘The Imperative of Fridge-Free Vaccines’ -European Pharmaceutical Review. December 2023. https://stablepharma.com/publications/.
“For the first time, vaccines reformulated by Stablepharma using our StablevaX technology, comply with the WHO definition of room temperature pharmaceuticals not requiring refrigeration, i.e. ‘showing no degradation after storage at 40°C and 75% RH for at least 6 months’.
The two most important properties of the trehalose molecule that makes it such a remarkable stabilising agent, are the very low residual energy of the chemical bond that joins the two glucose molecules together to make the disaccharide, and the strong tendency that solutions of trehalose have to form very concentrated viscous solutions, as they dry rather than to crystallise as most other sugars do. This combination of properties ensures that trehalose forms completely inert solid glass when properly dried, that entombs the product in a state of suspended animation, in which no chemical reactions can occur to spoil the product. Dry trehalose glasses remain solid and protective to well above 100 degrees centigrade, yielding room temperature storable products in even the hottest countries”.
StablevaX is an adaptable fridge-free technology which offers an extended shelf-life, reduces vaccine wastage and the CO2 footprint of the cold-chain.
Dr Bruce’s clear passion to bring fridge-free vaccines to market is becoming a reality. Stablepharma is progressing towards the first-in-human clinical trials for SPVX02, a fridge-free vaccine for the prevention of Tetanus and Diphtheria, and I asked Dr Bruce what did the future look like in terms of additional candidates for his fridge-free technology?
“Stablepharma’s aim to make “fridge free” vaccines and drugs available to the 80% of the worlds population that still do not enjoy access to reliable refrigeration, is now being driven forward by our scientific team and partners: we are embarking on our second vaccine, Tetanus toxoid as we speak, and already have historical data on about 10 other vaccines we have shown can be stabilised. We will, of course, make faster progress with the portfolio of about 60 suitable vaccines that we plan to develop, by partnering with more vaccine manufacturers to implement the change”.
Dr Bruce talked about the work of NGOs and the challenges they face on a daily basis. “It is important to realise that refrigerated storage is generally not a problem for vaccine manufacturers as they enjoy access to First World equipment and infrastructure, but it is a serious problem for the NGO’s, who largely purchase the vaccines for delivery in the field, worldwide. The WHO, MSF, UNICEF and others have been calling for the development of fridge free vaccines for many years. The current cold chain of refrigerators established by the WHO costs over $400 million per year; a sum which would obviously be better spent on vaccines for protecting children, rather than investing in and maintaining the chain of unreliable refrigeration”.
“In summary, Stablepharma has succeeded in making the first Fridge-Free vaccine in the world, has proven its stability and potency in a joint project with the European Manufacturer of the active components, BB-NCIPD Ltd and has progressed GMP manufacturing and Regulatory submissions for Approval. The age of Fridge-free vaccines is here (at last!).
Thank you Dr Bruce Roser for your continued passion and vision to make fridge-free vaccines a reality.