TTDR next-gen oncolytic virus


VG201 is the first product candidate built with our next generation Translational and Transcriptional Dual Regulated (TTDR) HSV-1 backbone and is uniquely engineered to enhance tumor-specific replication and payload expression without compromising safety. The two critical mechanisms of action of VG201 are the CEA promoter regulating ICP27 expression and miRNAs regulatingICP34.5 expression, which provide the VG201 selectivity in tumor cells versus non-tumor normal cells. VG201 also encodes IL12 & IL15/IL15Ra as cytokine payloads to further enhance both innate and adaptive anti-tumor activity.

VG201 is investigated as image guided, intratumoral injections (IT) in two Phase I clinical trials in US & China. And intravenous (IV) administration was approved by NMPA in January of 2024.

A first-in-human, open label, dose escalation trials for patients with advanced solid tumors that progressed after standard of care treatments is recruiting patients in the US at two sites.

Modality & Product Snapshot

Oncolytic Virus (next-generation TTDR backbone)
Oncolysis, immune cell activation

Target Indications

Solid Tumors

Route of administration


(intravenous) injection 


(intratumoral) injection

Our Approach & Differentiation

VG201 is Virogin’s first non-attenuated OV from the TTDR (Transcription Translation Dual Regulation) backbone family to enter the clinic.

  • Preclinical data suggests that VG201 is more potent than non-attenuated OVs with an acceptable safety profile.
  • Preclinical studies demonstrated synergistic effects with an anti PD-1 mAb and targeted therapies.

Clinical Proof of Concept

Key takeaways from our poster presentation at ASCO 2023. As of poster cut-off date

  • 18 patients have been dosed till date with a Disease Control Rate (DCR) of 67%.

  • Intratumoral (IT) administration of escalating doses of VG201 were well tolerated in heavily pretreated patients with advanced solid tumors with no DLTs.

  • Preliminary data including a partial response and disappearance of non-injected lesions demonstrated signs of monotherapy activity and systemic antitumor effect

  • PD-L1 elevation post injection suggests the use of VG201 in combination with check point inhibitor could solicit better anti-tumor activity.
  • Translational data demonstrated activation of the immune system and viral replication in the injected tumors

Looking Forward

We will continue with exploring the safety and efficacy of VG201 as monotherapy and combinations in various tumor types with focus on high unmet medical need populations for an expediated development process. The program is expected to expand into phase 2 clinical trials. Additional studies exploring the IV administration route for VG201 are progressing.





Registration Number


IND Approval

Phase I

Phase II



Solid Tumors




Solid Tumors




(VG161+ Nivolumab)

Solid Tumors