Trial results for a Phase 2 study investigating atezolizumab in patients with non-small cell lung cancer (NSCLC) or advanced solid tumors were posted on ClinicalTrials.gov on 2025-08-27. The study showed that the combination of atezolizumab and chemotherapy achieved an overall response rate of 50.0% in NSCLC patients previously treated with a PD-1 inhibitor, compared to 33.3% for chemotherapy alone.
Background
Atezolizumab (Tecentriq) is an approved immunotherapy that targets PD-L1. This Phase 2 study explored its efficacy in patients with non-small cell lung cancer (NSCLC) or advanced solid tumors who had previously received treatment with a PD-1 inhibitor, such as nivolumab or pembrolizumab. The trial aimed to evaluate new treatment strategies for these previously treated populations.
Trial design
The study (NCT03977467) was a Phase 2, two-part, open-label trial with an enrollment of 46 participants. It investigated atezolizumab and tiragolumab, or atezolizumab combined with standard of care (SOC) chemotherapy, in patients with non-small cell lung cancer or advanced solid tumors who had prior treatment with a PD-1 inhibitor. The trial included several arms: Arm A1 (NSCLC Chemo + Atezolizumab), Arm A2 (NSCLC Standard of Care Chemo), Arm B (Atezolizumab Only), and Arm B (Atezolizumab and Tiragolumab).
Key results
Key results from the trial focused on Overall Response Rate (ORR), Disease Control Rate (DCR), and the incidence of treatment-emergent adverse events (AEs).
- For Overall Response Rate:
- Arm A1 (NSCLC Chemo + Atezolizumab) showed an ORR of 50.0%.
- Arm A2 (NSCLC Standard of Care Chemo) showed an ORR of 33.3%.
- Arm B (Atezolizumab Only) showed an ORR of 7.9%.
- Arm B (Atezolizumab and Tiragolumab) showed an ORR of 0%.
- For Disease Control Rate:
- Arm A1 (NSCLC Chemo + Atezolizumab) showed a DCR of 50.0%.
- Arm A2 (NSCLC Standard of Care Chemo) showed a DCR of 33.3%.
- Arm B (Atezolizumab Only) showed a DCR of 7.7%.
- Arm B (Atezolizumab and Tiragolumab) showed a DCR of 100.0%.
- Regarding the incidence of treatment-emergent adverse events (AEs):
- Arm A1 (NSCLC Chemo + Atezolizumab) reported AEs in 4 participants.
- Arm A2 (NSCLC Standard of Care Chemo) reported AEs in 3 participants.
- Arm B (Atezolizumab Only) reported AEs in 34 participants.
- Arm B (Atezolizumab and Tiragolumab) reported AEs in 1 participant.
What this means
The results suggest that combining atezolizumab with chemotherapy may offer an improved overall response rate and disease control rate for patients with non-small cell lung cancer who have previously been treated with a PD-1 inhibitor, compared to chemotherapy alone. The data from the atezolizumab and tiragolumab combination arm showed a 0% overall response rate but a 100.0% disease control rate, indicating a high proportion of stable disease in that small subgroup. The varying incidence of adverse events across arms suggests different safety profiles for the investigated regimens.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03977467, titled "Atezolizumab and Tiragolumab in Patients With NSCLC or Advanced Solid Tumors Having Had Prior Treatment With a PD-1 Inhibitor," were posted on 2025-08-27 on clinicaltrials.gov.