Treatment-resistant panic disorder (TRPD) is characterized by persistent panic symptoms despite adequate pharmacological and/or psychotherapeutic treatment. This open-label study is designed to evaluate a self-guided cognitive behavioral therapy (CBT) protocol delivered via a mobile application for adults with TRPD. The intervention consists of eight weekly sessions covering psychoeducation, panic cycle interruption, cognitive restructuring, relaxation techniques, assertiveness training, behavioral strategies, and life reorganization. An avatar is incorporated to enhance engagement and simulate therapeutic presence. Participants continue their usual psychiatric follow-up and pharmacological treatment throughout the study. Outcomes are assessed at baseline and after completion of the intervention using validated measures of panic severity, anxiety, depression, mindfulness, coping strategies, quality of life, and affect.