Imugene to demonstrate the benefits of combination tumor treatment
Imugene Limited (ASX:IMU) has provided a promising update on the preliminary clinical development plan (CDP) for the proposed exclusive license of the patents covering the CF33 oncolytic virus technology, which is subject to shareholders’ approval at an Extraordinary Meeting of Shareholders to be held on 18 November, 2019.
The CF33 oncolytic virus (OV) was developed in the laboratory of Professor Yuman Fong, an internationally recognised surgeon and scientist at City of Hope, a California-based world-renowned independent research and treatment centre for cancer, diabetes and other life-threatening diseases.
CF33 has been developed in two different constructs.
One version of the OV is “armed” with an immune checkpoint inhibitor inserted in the virus, which is known as CheckVacc.
The other is an unarmed construct, known as Vaxinia, and Imugene plans to conduct two separate Phase 1 clinical trials in 2020 to test a CheckVacc construct and a Vaxinia construct of the OV.
Early positive signs in breast cancer studies
Pre-clinical studies conducted at City of Hope by Professor Fong have shown encouraging results in triple negative breast cancer (TNBC) when CF33 is combined with an immune checkpoint inhibitor (ICI), specifically a PD-L1 inhibitor to yield CheckVacc.
TNBC is an aggressive subtype of breast cancer affecting 20% of breast cancer patients with poor prognosis upon diagnosis of metastases, largely due to lack of effective targeted therapy.
Immune check point inhibitors have shown efficacy in TNBC1s.
In March 2019 the FDA approved Genentech’s, member of the Roche group, PD-L1 ICI Atezolumumab (Tecentriq) for TNBC.
Immune checkpoint blockade has shown great promise as novel class of drugs to treat certain types of advanced cancers in the last five years.
However, only a limited percentage of cancer patients achieve objective clinical responses through ICI treatments, leaving significant room for improvement partly due to complicated regulatory circuits of immune functions in cancer.
Professor Fong’s pre-clinical studies have 1shown that CF33/ICI combinatorial therapy may be applicable to a much wider population of cancer patients, and there is increasing commentary in medical journals suggesting that combination therapy offers the best of both worlds.
The Phase 1 trial commencing in 2020 will be an open-label, dose-escalating, non-randomized, single-centre phase 1 study of CheckVacc administered intratumorally in patients with metastatic TNBC with injectable metastatic lesions.
The purpose of the study will be to evaluate the safety and initial evidence of efficacy of the CF33-antiPDL1 combination oncolytic virus against TNBC.
CF33 progress bodes well for Vaxinia
Imugene referenced commentary from numerous high-impact medical journals in noting that impressive activity of the CF33 oncolytic virus Vaxinia has been demonstrated in multiple solid tumour types in validated invivo models of pancreatic, colorectal, lung, TNBC and colon cancers.
Importantly, Vaxinia outperforms the industry leading OV’s from Amgen and Genelux.
Vaxinia is more potent than its competitors and a strong advantage is the level of dosing required, at least in preclinical animal models, is much lower.
The Phase 1 MAST (Mixed Advanced Solid Tumors) trial commencing in 2020 will be an FDA IND Imugene sponsored open-label, dose-escalating, non-randomised, multi-centre (including Australian hospitals) phase 1 study of Vaxinia administered intratumorally or intravenously in patients with solid tumors (lung, TNBC, melanoma, bladder, GI).
The purpose of the study will be to evaluate the safety and initial evidence of efficacy of the CF33 Vaxinia oncolytic virus against solid tumors.