Tiraglolumab Atezolizumab and Chemoradiotherapy in Localized Anal Carcinoma (TIRANUS)

The peculiarity of anal cancers, with well-established radical chemoradiotherapy that allows tumor-neoantigen formation with platinum-based chemotherapy and radiotherapy with radio-sensitizing chemotherapy could create the perfect environment for immunotherapy in this setting, not only to increase the probability of pathological complete response (CCR) but also creating neoantigen exposure and immune-prevention to reduce the relapse after surgery. TIRANUS trial is a Phase II, single-arm, open-label, non randomized, non controlled recruiting treatment-naive localized squamous cell carcinoma of the anal canal and are candidates for radical chemoradiotherapy. The trial hypothesizes that the addition of immunotherapy (atezolizumab and tiragolumab) to standard chemoradiotherapy in localized squamous cell carcinoma of the anal canal may improve the CCR at the end of consolidation phase. The study will assess, as the primary endpoint, the CCR, defined as the percentage of patients who have achieved complete response (CR), disappearance of all target lesions and no presence of residual disease assessed by biopsy at the end of consolidation phase. Secondary objectives include survival, safety of the combination, patient reported quality of life, and a substudy of molecular biomarkers determined in tumor biopsy and blood samples. The main question\[s\] it aims to answer are: 1. To determine the efficacy of atezolizumab plus tiragolumab concomitantly with chemoradiotherapy in patients with localized squamous cell carcinoma of the anal canal evaluating the clinical response to treatment. 2. To evaluate safety of the intended treatment regimen and Health-related quality of life (HRQoL) in this treatment regimen All patients will receive atezolizumab plus tiragolumab for 2 cycles in concomitance with the 6 weeks of standard scheduled chemoradiotherapy. (cisplatin, 5-Fluorouracil and radiotherapy). After the concomitant phase, patients will enter a consolidation phase and will receive atezolizumab in combination with tiragolumab up to 24 weeks. Patients will discontinue treatment in case of confirmed progression, toxicity, patient criteria, or physician criteria.