Equine Sarcoids – Visible Success with DelNS-based Immunotherapy Leads the Way Towards Cancer Therapy in Humans

Scientists from the Viennese biotech company BlueSky Immunotherapies GmbH (Ltd.) have used their viral vector platform delNS to treat sarcoids in horses. In cooperation with the oncology team of the University of Veterinary Medicine Vienna led by Sabine Brandt and the sarcoid expert Edmund Hainisch they have achieved sensational, success that leads the way towards new options in the development of innovative and easy-on-the-body cancer therapies in humans.

Equine sarcoids (see images in the appendix) are locally aggressive skin tumours. They are induced by tumour antigens E6 and E7 of the bovine papillomavirus and seriously compromise the health and welfare of the affected animals. Conventional treatment options such as surgical excision or chemotherapy have only limited effect and typically result in the recurrence of the tumours.

As published in the last issue of PLoS ONE, sarcoids treated with delNS/E6E7 were completely and permanently eliminated. Moreover, the systemic delNS-mediated immune stimulation eliminated also non-injected sarcoids. The study also demonstrated that the papillomavirus that caused the sarcoids was eliminated.

With its proprietary delNS technology, the biotech company BlueSky Immunotherapies GmbH (Ltd.) has created a viral vector platform for the induction of interferon and the expression of tumour antigens. delNS-based vectors have many properties for overcoming the immunosuppressive environment of tumours.

delNS vectors

• induce a strong interferon response
• (Interferons are proteins that have an immunostimulatory, especially antiviral and antitumoural effect.)
• activate T cells, dendritic cells and natural killer cells (essential cells for the immune system)
• inhibit immunosuppressive cells

We designed, manufactured and used two types of delNS vectors for the local treatment (direct injection into the tumours) of the horses. The clinical study comprised a period of three years, 29 horses and different treatment regimes. Visible and very significant regression of the sarcoids was achieved in 20 of the treated horses, and 100% regression of the sarcoids in 10 equine patients. “The complete elimination of very aggressive and difficult-to-cure equine sarcoids is yet another important proof of the potential offered by our delNS platform. We are therefore confident that we will also be able to successfully heal and/or eliminate the cervical tumours of the women enrolled in the clinical trials currently under way”, explains Thomas Muster, CEO of BlueSky Immunotherapies.

Summary of the results obtained in 2021:

• Complete regression: 10 horses
• Ongoing regression: 10 horses
• Transient regression: 3 horses
• No regression: 6 horses