Trial results for a Phase 2 study investigating atezolizumab with or without tiragolumab in metastatic and/or recurrent PD-L1-positive cervical cancer were posted on ClinicalTrials.gov on 2025-02-07. The combination of atezolizumab plus tiragolumab achieved an Independent Review Committee (IRC)-assessed objective response rate (ORR) of 19.0%, compared to 15.6% for atezolizumab monotherapy.
Background
The study investigated treatment options for participants with metastatic and/or recurrent PD-L1-positive cervical cancer, a challenging malignancy with unmet medical needs.
Trial design
This completed Phase 2 study (NCT04300647) enrolled 172 participants with metastatic and/or recurrent PD-L1-positive cervical cancer. The trial evaluated the efficacy and safety of tiragolumab in combination with atezolizumab, and atezolizumab monotherapy. Participants were assigned to either the atezolizumab monotherapy arm or the atezolizumab plus tiragolumab combination arm during the pre-crossover period.
Key results
Key efficacy and safety outcomes were reported for the pre-crossover period:
- The Independent Review Committee (IRC)-assessed Objective Response Rate (ORR) was 15.6% for atezolizumab monotherapy and 19.0% for the atezolizumab plus tiragolumab combination.
- The IRC-assessed Disease Control Rate (DCR) was 20.0% for atezolizumab monotherapy and 31.0% for the atezolizumab plus tiragolumab combination.
- Investigator-assessed Best Clinical Response (BCR) Rate was 33.3% for atezolizumab monotherapy and 44.4% for the atezolizumab plus tiragolumab combination.
- The median IRC-assessed Duration of Response (DOR) for the atezolizumab plus tiragolumab combination was 11.8 months. The median Investigator-assessed Duration of BCR for atezolizumab monotherapy was 7.0 months.
- Regarding safety, 41 participants experienced adverse events (AEs) in the atezolizumab monotherapy arm during the pre-crossover period, while 118 participants experienced AEs in the atezolizumab plus tiragolumab combination arm during the pre-crossover period. An additional 14 participants experienced AEs in the atezolizumab plus tiragolumab arm during the post-crossover period.
What this means
The results from this Phase 2 study suggest that the combination of atezolizumab and tiragolumab may offer an improved objective response rate, disease control rate, and best clinical response rate compared to atezolizumab monotherapy in patients with metastatic and/or recurrent PD-L1-positive cervical cancer. The observed median duration of response for the combination therapy also indicates sustained benefit. While the combination arm reported a higher number of participants with adverse events, further context on severity and causality would be necessary for a full safety assessment. These findings warrant further investigation in larger trials to confirm efficacy and establish the safety profile of the combination therapy.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04300647, titled "A Study of Tiragolumab Plus Atezolizumab and Atezolizumab Monotherapy in Participants With Metastatic and/or Recurrent PD-L1-Positive Cervical Cancer," were posted on 2025-02-07 on clinicaltrials.gov.