RhoVac has conducted proof-of-principle ex vivo studies (studies on human cancer cells) which have demonstrated that the T-cell response can be triggered and that the T cells can be programmed to attack and eliminate cancer cells. Notably, the studies have also demonstrated that the same programmed T cells eliminate metastatic cancer cells from different types of cancer. Cancers that have been tested in RhoVac’s ex vivo studies include breast cancer, bowel cancer and melanoma. This is confirmation of the generally-held scientific theory underlying RhoVac’s immunotherapy – that RhoC is overexpressed in all metastatic cancer cells regardless of the type of cancer.
Reported research results demonstrate that, in addition to the cancer indications identified above, the high concentration (overexpression) of the RhoC protein in metastatic cancer cells can also be seen in numerous cancers including prostate, stomach, ovarian, bladder, pancreatic, non-small cell lung, hepatic, oesophageal, brain and throat (Karlsson et al. 2009) 1 and many others. It is therefore relevant to assume that RhoVac cancer vaccine product RV001 can potentially be used for all types of metastatic cancers.
Toxicology Study Complying with the GLP Standard
The toxicology study conducted by RhoVac for scientific purposes (non-GLP) demonstrated that there were no adverse reactions of clinical relevance associated with injection of the company’s immunotherapy. Transient irritation has been identified at the injection site. However, this is a known reaction to this type of treatment and is not related to RV001 but to the use of the adjuvant ((Montanide™) which is used to further stimulate the immune response. To get approval to begin clinical studies, RhoVac needed to conduct a toxicology study in accordance with the GLP standard. The company started this study during Q4 2015 and reported the top line result in Q2 2016. The study was conducted in mice and included five groups each containing ten subjects. The mice were treated for eight weeks. The study revealed no indication of systemic toxicity, only local reactions at the injection site attributable with the use of Montanide™. The conclusion of this study is therefore the same as that of the initial toxicology study in that there are no adverse reactions to RV001.
Clinical Phase I/II Studies
Once preclinical work had been completed, a clinical trial application was submitted to appropriate authorities (each country’s Research Ethics Committee and Medical Products Agency) to start clinical studies. Clinical studies could commence once this application had been approved. Clinical studies are conducted in several phases (Phases I, II and III). RhoVac’s first clinical study, which started early 2017, was a Phase I/II Study that included 22 patients diagnosed with metastatic prostate cancer. The primary goal of the study was to evaluate the safety of treatment with RV001. In addition, the study evaluated whether RV001 could induce specific immune responses. The treatment of the patients were finalized in February 2018 and top line-results were published in August 2018 (see press release:https://www.rhovac.com/rhovacs-reports-positive-results-in-the-companys-phase-i-ii-clinical-study/).
Phase IIb Study
Since RhoVac’s Clinical Phase I/II Study was completed with good results, the company can continue the clinical development in the Phase IIb Study. In this phase, we continue with the same cancer indication we studied in the Phase I/II Study i.e prostate cancer. However, we can also develop other cancer indications directly into Phase IIb as the results obtained in the Phase I/II Study are adequate for Phase I/II clinical documentation for other metastatic cancer indications.
1 Karlsson R, Pedersen E.D, et al (2009). Rho GTPase function in tumorgenesis. Biochem Biophys Acta 1796: 91-98