Clinical trial results published by Vir Biotechnology or reputable medical journals

Vir Biotechnology's T-Cell Engagers Show Promising Data, Shares Surge 70%

Jan 8, 2025, 04:05 PM

Vir Biotechnology has reported promising early data from its ongoing dose escalation trials for two dual-masked T-cell engagers, VIR-5818 and VIR-5500. These therapies, licensed from Sanofi in August 2024 as part of its $1 billion Amunix acquisition, target HER2 and PSMA, respectively, and are being tested for efficacy and safety in solid tumors and metastatic castration-resistant prostate cancer (mCRPC). VIR-5818 showed partial responses in heavily pretreated HER2-expressing cancers, with a 16% rate of grade 3 or higher adverse events. VIR-5500 demonstrated a 58% PSA50 response rate in mCRPC patients at higher doses, with a manageable 25% cytokine release syndrome (CRS) rate. The therapies feature masking technology designed to improve therapeutic index and reduce toxicity. Vir’s share price surged by 70% following the announcement. Enhertu, a competitor, has shown a 47% objective response rate (ORR) in HER2-positive colorectal cancer, offering a benchmark for comparison. With over $1.2 billion in cash reserves, Vir continues dose escalation and positions itself as a potential leader in oncology after pivoting from its earlier focus on infectious diseases.