This study will examine the efficacy and safety of a self-guided digital therapeutic app for the adjunct treatment of Major Depressive Disorder compared to a control app in adolescents and adults.

This study aims to examine the efficacy of a self-guided digital therapeutic app for depression compared to a control app in individuals aged 13 and older with a diagnosis of Major Depressive Disorder. The primary outcomes are patient- and clinician-reported depression symptom severity after 5 weeks.

Inclusion Criteria:

• Positive self report screen for depression
• Participant is at least 13 years of age
• Willing and able to provide informed consent; if under 18 years of age, willing and able to provide assent, and has a legal guardian willing and able to provide consent
• Primary diagnosis of Major Depressive Disorder (MDD)
• Under the care of a United States (U.S.)-based licensed healthcare provider and willing and able to provide contact information for the provider and sign a HIPAA release that allows investigator to contact provider
• Fluent and literate in English
• Has access to a compatible device and operating system (i.e., capable of installing the app from the Google Play or Apple App Store) and regular internet access
• Located in the continental U.S., Hawaii, or Alaska, and not planning to leave the U.S. during the primary study period

Exclusion Criteria:

• Has changed or initiated psychotherapy with a mental health professional within 30 days prior to eligibility screening
• Has received certain types of psychotherapy within the last 6 months
• Has changed prescribed psychotropic medication (initiation or change in dose) within the past 30 days
• Plans to initiate or change treatment (e.g., psychotherapy, psychotropic medication, and/or other psychosocial treatment) for a mental health disorder during study intervention period
• Suicidal behavior within the past year
• Active suicide ideation with intent within the past 3 months
• Previously participated in user testing or a clinical study at Limbix Health Inc. or Big Health Inc. (such as the STAND study or Rise study), or have used a Limbix app
• Participated in any other clinical research involving an intervention or treatment within the past 60 days
• Plans to participate in any other clinical research involving an intervention or treatment during the study intervention period
• Living in the same household as another participant in the study (e.g., a sibling)
• Has a diagnosis of MDD with psychotic features or comorbid Psychotic Disorder
• Has a concurrent diagnosis of (or has been treated for) bipolar disorder I and II or severe substance use disorder within the past year
• Has treatment resistant depression
• Is employed by Big Health Inc., or is a collaborator, associate, or relation of Big Health Inc. staff
• Any condition, comorbidity, or event (other than the above) that, in the opinion of the investigator, will prevent the participant from adhering to the protocol or benefitting from the intervention, or will prevent investigators from being able to ensure safety