PBI-MST-01 (NCT04541108) Substudy AZN-05: Intratumoral Microdosing of Rilvegostomig, Volrustomig, Sabestomig, and AZD9592 in HNSCC

The CIVO Microdose Injection Device (MID) simultaneously delivers multiple drugs and drug combinations (Up to 8), each in microdose amounts, into a single patient tumor and enables comparisons of the resulting biomarker responses that occurred while that tumor was still in the native microenvironment. AstraZeneca is developing three novel assets: rilvegostomig, volrustomig, and sabestomig, all of which are bispecific monoclonal antibodies designed to stimulate antitumor immunity. In this Phase 0 clinical trial, the PD effects of these investigational assets in the TME of patients presenting with HNSCC will be evaluated. These investigational assets will be injected alone in microdose quantities at tumor sites in HNSCC patients. Pembrolizumab, also used therapeutically in this patient population, will be included in the CIVO injection array administered as a single agent. In addition, microdoses of AZD9592, a novel antibody drug conjugate (ADC), alone or in combinations with the evaluated biologics will also be assessed. The CIVO-injected portion of the tissue will be analyzed for localized response at sites of drug exposure in the TME.