Purespring Therapeutics has become the first company to successfully treat kidney disease models by directly targeting the podocyte – a specialised cell implicated in approximately 60% of renal diseases. 

The company has developed a proprietary adeno-associated viral (AAV) gene therapy platform, building on the pioneering research by Professor Moin Saleem, Professor of Paediatric Renal Medicine at Bristol Medical School. 

Gene therapy — a technique which replaces or alters a faulty gene or adds a new gene to treat or prevent disease instead of using drugs or surgery, offers a potential new type of treatment for renal conditions. 

Purespring’s platform approach enables streamlined gene therapy development for renal diseases, offering the potential to halt, reverse and even cure both rare and common kidney diseases. 

The oversubscribed Series B financing round was led by Sofinnova Partners, in collaboration with a prominent syndicate including Gilde Healthcare, Forbion, British Patient Capital and founding investor Syncona Limited.  

Proceeds will be used to support Purespring’s pipeline including the initiation of a Phase I/II clinical trial for IgA Nephropathy (IgAN), a common, chronic kidney disease primarily affecting young adults.  

About one third of IgAN patients will go on to lose their kidney function within five years and require a kidney transplant or dialysis.  

Professor Moin Saleem said: “This is world leading work, co-led by Professor Gavin Welsh and Dr Wen Ding that has emerged out of 25 years of work and expertise developed in Bristol Renal in podocyte biology and glomerular diseases.  

“The potential here is to generate curative therapies for kidney diseases with huge unmet need, and this investment will allow us to get to clinical trials in the two lead indications. We hope to progress on the gene therapy platform that we have built, to address further glomerular diseases that stem from podocyte damage, and continue to build new treatments for even more clinical indications in the kidney field.” 

Professor Jeremy Tavare, Pro Vice-Chancellor for Health and Life Sciences at the University of Bristol, said: “The significant progress made by Purespring in translating UoB’s ground-breaking research in renal gene therapy has been recognised by a high-calibre investment syndicate. Their expertise and resources will allow the company to continue their impressive trajectory and enable the clinical development of much-needed therapies for patients suffering from chronic kidney diseases.” 

Julian Hanak, Purespring’s Chief Executive Officer, added: “Nearly one tenth of the world’s population, around 840 million people, suffer from chronic kidney disease. For many of them, there are few options beyond dialysis and transplantation. Our novel treatment platform and deep understanding of kidney disease puts us in a position to stop, reverse and even cure kidney disease. The funds raised will allow us to bring our novel treatments to patients in the clinic.  

“I’m really pleased to be able to welcome such a high-quality investor syndicate to support Purespring on this journey. Having sophisticated, experienced and committed investors on board, who understand drug development and the urgency of bringing these much-needed therapies to patients will maximise the opportunities for the company and the patients we treat.”  

The financing follows critical scientific milestones for Purespring. Earlier this year, Purespring presented preclinical data at the 61st European Renal Association (ERA) Congress establishing the potential of AAV gene therapy to deliver transgenes to the podocyte to replace defective genes or to modulate protein production, underpinning the potential of AAV as an important novel modality to treat a broad range of kidney disease. 

In 2023, a paper published in Science Translational Medicine demonstrated that Purespring had successfully used AAV gene therapy to transduce the podocyte in vivo for the first time – a major milestone in overcoming the hurdles which have previously limited development in this area.  

Purespring will present itsIgAN data publicly for the first time at the American Society of Nephrology (ASN) Kidney Week congress on October 26 in San Diego. 

Maina Bhaman, Partner at Sofinnova Partners, said: “Purespring Therapeutics is pioneering the treatment of kidney disease. The team’s ambition and calibre epitomise Sofinnova’s mission of scientific and entrepreneurial excellence in delivering transformative treatments to patients. We are excited to support the Purespring team as they bring their groundbreaking innovation to the global stage.”  

Michael Kyriakides, Investment Partner at Syncona Investment Management and Board Director of Purespring Therapeutics, said: “Syncona founded Purespring with the vision of creating the world’s leading kidney gene therapy company, and we have been impressed with its progress.  

“Today’s financing and the strong syndicate of investors that the Company has attracted broadens Purespring’s financial scale and clearly validates its technology, strategy and execution to date. We look forward to working alongside Purespring and its new syndicate as it prepares for its Phase I/II clinical trial.”