SAN DIEGO, Dec. 20, 2021 (GLOBE NEWSWIRE) -- Sorrento Therapeutics, Inc. (Nasdaq: SRNE, "Sorrento") today announced that the U.S. Food and Drug Administration (FDA) has granted clearance to proceed with a Phase 1b clinical trial using STI-1386, Seprehvec™, entitled “Dose Escalation Study of the Safety and Preliminary Efficacy of STI-1386 Oncolytic Virus in Patients with Relapsed or Refractory Solid Tumors.”
STI-1386, or Seprehvec, is a 2nd generation oncolytic herpes simplex virus type 1 (oHSV) developed following the acquisition of Virttu Biologics by Sorrento in 2017 and produced in Sorrento’s GMP virus therapeutics manufacturing facility. The Seprehvec backbone is deleted of both RL1 gene copies, eliminating expression of the neurovirulence factor ICP34.5 and restricting virus proliferation to cells which are rapidly dividing, i.e., tumor cells. Seprehvec additionally expresses transgenes encoding an anti-PD-1 scFv-Fc isolated from the Sorrento G-MAB antibody library, a TGF beta receptor 2 decoy, and interleukin-12.
These transgene-encoded proteins secreted by Seprehvec-infected tumor cells are designed to act in a coordinated fashion to enhance immune-mediated tumor destruction by i) inhibiting the PD-1/PDL-1 immune checkpoint pathway, ii) diminishing the immunosuppressive effects of TGF beta in the tumor microenvironment, and iii) providing a localized IL-12 signal to activate and attract T cells and NK cells to the tumor.
“Seprehvec allows for locoregional immune stimulation at the tumor site while potentially minimizing the undesired effects that may accompany systemic immune stimulation. Our initial focus is to develop Seprehvec for treatment of sarcomas, pancreatic carcinomas, and hepatic metastases, with expansion to additional solid tumor indications in the future,” said Mike Royal, MD, JD, MBA, Chief Medical Officer of Sorrento.
Robert Allen, PhD, Senior Vice President of Antiviral and Oncolytic Immunotherapy Development, commented, “Seprehvec provides a unique means of simultaneously bringing multiple tumor-killing and tumor-suppressing elements to bear on solid tumors, which are notoriously hard to eradicate. Using this same approach, we are currently progressing additional oHSV candidates that mediate recruitment and activation of anti-tumor responses from specific subsets of immune cells. The virologists, cancer immunologists, and manufacturing scientists at Sorrento continue to leverage the breadth and quality of the G-MAB library, delivering best-in-class next-generation oHSVs, antibodies, and cellular immunotherapies to patients.”
