RhoVac reports interim results on immunological response with RV001

Nov 18, 2019

Today, 18th November 2019, RhoVac AB ("RhoVac") reports interim results from ongoing immunological studies at University of Tübingen, Germany concluding that treatment with RV001 can activate CD4+ T-cells and also CD8+ T-cells.

In July 2019 RhoVac published results on the follow-up phase of the phase I/II clinical study and in relation to the immunological response it could be concluded that 18 patients showing significant treatment related immunological response at completion of treatment. All 18 patients still showed significant response at 3-, 6- and 9-months follow-up. At the 12-months follow-up, 17 out of the 18 responding patients still showed significant immunological response.

Ongoing immunological studies at the University of Tübingen now confirm that treatment with RV001 can activate CD4+ T-cells and also CD8+ T-cells. Confirmation that the drug candidate RV001 can activate CD4+ T cells is important for the clinical value of the treatment. This has been demonstrated in a number of scientific publications of which some are referenced below:

• Doonan et al (2010), demonstrated that “activation of CD4+ T cells is required to stimulate and prolong CD8+ T cell activity, and for the development of long-lasting tumor specific memory T cells”.
• Quezeda et al (2010) concluded in their study that “results highlight the relevance of the CD4+ T cell compartment, and particularly of cytotoxic CD4+ T cells, in cancer immunotherapy, while providing evidence that T cell differentiation in vivo may afford advantages over current approaches using differentiation and expansion in vitro”.
• Haabeth et al (2014) also concluded that beside CD8+ T cells commonly known as being able to eliminate target cells, CD4+ T cells also have the ability to directly eliminate tumors via T Cell Receptor and peptide:MHC-class II interaction (the pathway linked to CD4+ T cells) and/or to eliminate tumor cells indirectly via the release of immunomodulatory molecules activating surrounding immune cells.

For these reasons the MHC class II tumor antigen presentation pathway (the pathway linked to CD4+ T cells) must be utilized for therapeutic cancer vaccines to have a high clinical value, and interim results strongly indicate that RV001 is well capable of this.

Comment from RhoVac's CEO, Anders Månsson: 

- Confirmation of the immunological response concluded based on interim results is obviously important data for the ongoing development of the drug candidate RV001. I am looking forward to the continued collaboration with the team at University of Tübingen.