Summary
SMARCB1 or SMARCA4 deficiency means that tumour cells are missing the SMARCB1 and SMARCA4 genes, which is seen with some aggressive cancers that are typically hard to treat. Immunotherapy with monoclonal antibodies, such as tiragolumab and atezolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumour cells to grow and spread.
The study has two parts, and eligible participants are assigned to Part A or Part B.
In Part A, participants will receive tiragolumab intravenously (IV) on Day 1 of each cycle and atezolizumab IV on Day 1 of each cycle starting in Cycle 2. Treatment repeats every 21 days for up to 5 years. Part A is recruiting people aged between 12 months an under 18 years.
In Part B, participants will receive atezolizumab IV on Day 1 and Tiragolumab IV on Day 1 of each cycle. Treatment repeats every 21 days for up to 5 years. Part B is recruiting people aged over 12 months, with no upper age limit.
Participants will also undergo standard imaging scans including x-rays, CT, MRI and/or PET-CT through the trial. Participants also undergo blood sample collection on study. After completion of study treatment, participants are followed up at months 3, 6, 9, 12, 18, 24, 36, 48 and 60, up to 5 years.