DNX-2440

To test this hypothesis, we evaluated the changes in gut microbiota in two mouse cohorts: (1) GSC-005 glioblastoma-bearing mice treated orally with indoximod, an immunotherapeutic agent, or with Delta-24-RGDOX by intratumoral injection and (2) a mouse cohort harboring GL261-5 tumors used to mechanistically evaluate the importance of CD4+ T cells in relation to viroimmunotherapy efficacy. The CD4+ T cell depletion was associated with gut dysbiosis, lower mouse survival, and lower antitumor efficacy of the therapy. These findings suggest that microbiota modulation along the gut-glioma axis contributes to the clinical efficacy and patient survival of viroimmunotherapy treated animals.

P1, N=30, Suspended, DNAtrix, Inc. | Trial completion date: Dec 2023 --> Dec 2026 | Recruiting --> Suspended | Trial primary completion date: Jul 2022 --> Jul 2026

Therefore, our data demonstrate that, as an adjuvant therapy followed TAA-targeting T cells in localized treatment, Delta-24-RGDOX activates TME and promotes antigen spread, leading to efficacious systemic antitumor immunity to overcome tumor relapse. Adjuvant therapy with oncolytic viruses promotes antigen spread to potentiate localized intratumoral adoptive T-cell therapy with limited TAA targets, leading to sustainable systemic antitumor immunity to overcome tumor relapse.

Our data identified for the first time the in vivo role of IDO-dependent immunosuppressive pathways in the resistance of solid tumors to oncolytic adenoviruses. Specifically, the IDO-Kyn-AhR activity was responsible for the resurface of local immunosuppression and resistance to therapy, which was ablated through IDO inhibition. Our data indicate that combined molecular and immune therapy may improve outcomes in human gliomas and other cancers treated with virotherapy.

Thus, we engineered Delta-24-RGDOX (DNX-2440), an oncolytic adenovirus that carries the cDNA of the T-cell activator, OX40L...Specifically, the activity of the tumor microenvironment IDO circuitry was responsible, at least partially, for the remodeling of local immunosuppression after tumor infection. Combining molecular and immune-related therapies may improve outcomes in human gliomas treated with virotherapy.

In summary, our data showed that treatment of solid tumors with Delta-24-RGDOX induces robust remodeling of the tumor microenvironment and produces anti-tumor effects leading to decrease in tumor volume, along with a delay in the development and in the reduction of the number of metastases. These data suggest that Delta-24-RGDOX should be tested in the clinical setting in patients with metastatic breast, gastric and lung cancers.

In summary, our study indicates the virus induces antigen spread, resulting in expansion of antitumor T cell repertoire to prevent cancer relapse in adoptive T cell therapy (ACT). Our data demonstrate that Delta-24-RGDOX collaborates with ACT to induce more potent systemic immunity against the tumors, leading to sustainable tumor regression.

These data show that Delta-24-RGDOX adenovirus expresses a functional OX40L that can modulate the immune response, leading to a significantly improved survival outcome in DMG models.

Our group has developed and tested in preclinical models and in clinical trials for patients with recurrent glioblastoma the anti-tumor effect of oncolytic adenovirus Delta-24-RGD, also named DNX-2401, resulting with a 20% of long-term survivors, and the awaking of a antitumoral immunity after the administration of the pathogen...To test the hypothesis, 4T1 tumor bearing mice were subjected to the local administration of Delta-24-RGD and its armed derivatives, expressing expressing immune co-stimulatory ligands OX40L (Delta-24-RGDOX or DNX-2440) and GITRL (Delta-24-GREAT)...In conclusion, immunological studies indicate that viroimmunotherapy enhances the infiltration and activation of T-cell specific anti-tumor response, stagnating primary tumor growth and metastasis leading ultimately to increase in overall survival. Therefore, we conclude that armed-oncolytic Delta-24-RGD based adenoviruses hold great potential in treatment of primary and metastatic breast cancer.

Then mice were treated with intratumoral injections of control (PBS) or a combination of Delta-24-RGDOX and Indoximod, an inhibitor of the immune modulator IDO. Importantly, increase in Bifidobacterium and Lactobacillus was associated with a better response to the therapy, likely strengthening antitumor immunity and raising efficacy in viroimmunotherapy-treated mice. This reveals the benefits of gut microbiome therapeutics in positively influencing the final clinical outcome of viroimmunotherapy.

Collectively, the results demonstrate that Delta-24-RGDOX collaborates with ACT to induce more potent systemic immunity against the tumors, leading to more sustainable tumor regression and improved survival rate. Our study suggests the virus induces antigen spread, resulting in T cell repertoire to target more tumor-associated antigens to overcome cancer relapse due to cancer heterogeneity and limited targets in ACT and CAR T therapy.

Immune modulator coding sequences inserted in place of E3 in the DNX-2401 backbone expressed properly localized and biologically active transgenes. DNX-2440 infected tumor cells expressed OX40L localized to the cell surface capable of stimulating OX40-expressing T cells. Tumor cells infected with a second virus, which was engineered to express a cytokine, secreted high levels of active protein.