GeoVax's Gedeptin® Shows Favorable Safety and Disease Stability in Recurrent Head & Neck Cancer Trial

A peer-reviewed article published in JCO Oncology Advances reports findings from a Phase 1/2 clinical trial evaluating GeoVax Labs' Gedeptin® therapy for recurrent head and neck cancers. The study demonstrated an acceptable safety profile with no new safety signals and clinical evidence of disease stability in 37.5% of patients with end-stage disease who had exhausted all standard treatments.

The trial enrolled patients with recurrent head and neck cancers who had undergone a median of four prior lines of systemic therapy. Patients received therapy on a 28-day schedule consisting of intratumoral Gedeptin injections followed by intravenous fludarabine. Serious adverse events were uncommon and generally unrelated to treatment, with no deaths attributed to study therapy. Tumor biopsies confirmed successful tumor transduction and PNP transgene expression in all evaluable patients, supporting the mechanistic foundation of the Gedeptin platform.

J. Marc Pipas, MD, Executive Medical Director, Oncology of GeoVax, stated that the publication reinforces the strong scientific rationale underpinning the Gedeptin platform. He noted that even in this highly refractory patient population with extensive prior treatment, repeated intratumoral dosing demonstrated a favorable safety profile and evidence of disease stability. The correlative analyses confirming robust tumor transduction and PNP expression represent a critical mechanistic milestone for gene-directed enzyme prodrug therapy.

Kelly T. McKee, MD, MPH, Chief Medical Officer of GeoVax, added that these results support continued development of Gedeptin in settings where tumor burden is lower, patients are less heavily pretreated, or where combination strategies may amplify therapeutic benefit. This aligns with the company's strategy to advance Gedeptin into neoadjuvant studies for surgically resectable recurrent head and neck cancers. The study results suggest that earlier intervention, higher vector dosing, improved tumor transduction, or combination therapy with immune checkpoint inhibitors may further increase efficacy.

David Dodd, Chairman & CEO of GeoVax, stated that the publication in the ASCO journal underscores both the scientific significance of this trial and the need for new approaches to treat recurrent head and neck cancers. Gedeptin's targeted mechanism, combined with its repeat-dosing feasibility, offers a promising therapeutic option for patients. The company looks forward to expanding development into earlier disease settings and into rational combination regimens.

Gedeptin is a non-replicating adenoviral vector delivering the E. coli purine nucleoside phosphorylase (PNP) gene directly into tumor tissue. Following intratumoral injection, patients receive systemic fludarabine, which is converted in PNP-expressing tumor cells into a potent cytotoxic metabolite. Key characteristics include a tumor-agnostic mechanism of action, strong bystander effect, immune-sensitizing properties that may improve responses to immune checkpoint inhibitors, and a favorable safety profile demonstrated across early studies. For more information about clinical trials and other updates, visit https://www.geovax.com.

The implications of these findings are significant for the oncology field and patients with recurrent head and neck cancers. The demonstration of safety with repeated dosing opens possibilities for longer-term treatment regimens, while evidence of disease stability in end-stage patients suggests potential for greater efficacy in earlier disease stages. The confirmed tumor transduction and PNP expression provide validation for the GDEPT approach, which could have applications beyond head and neck cancers given the platform's tumor-agnostic mechanism. The potential for combination with immune checkpoint inhibitors represents a promising therapeutic strategy that could enhance treatment outcomes across multiple cancer types.