Trial results for the combination of atezolizumab and cobimetinib in treating participants with advanced or refractory rare tumors were posted on ClinicalTrials.gov on 2025-05-28. For the subgroup of small bowel adenocarcinoma, the study reported an Overall Response Rate (ORR) of 2 participants, a Disease Control Rate (DCR) of 45 percentage of participants, a median Progression-Free Survival (PFS) of 2.4 months, and a median Overall Survival (OS) of 8.8 months.
Background
The Phase 2 trial (NCT03108131) investigated the efficacy of combining cobimetinib and atezolizumab in patients with advanced or refractory rare tumors. Cobimetinib is explored for its potential to inhibit tumor cell growth by blocking enzymes essential for cell proliferation. Atezolizumab, an immunotherapy, is designed to stimulate the body's immune system to target cancer cells and impede their growth and spread. The study aimed to determine if this combination could offer an improved treatment approach for these challenging cancers.
Trial design
The study, titled "Cobimetinib and Atezolizumab in Treating Participants With Advanced or Refractory Rare Tumors" (NCT03108131), was a Phase 2 trial that enrolled 49 participants. The conditions investigated included Skin Squamous Cell Carcinoma, Appendix Adenocarcinoma, Rare Lesion, Locally Advanced Malignant Neoplasm, and Locally Advanced Skin Squamous Cell Carcinoma. The trial evaluated the combined use of atezolizumab and cobimetinib.
Key results
For the subgroup of participants with Small Bowel Adenocarcinoma, the following key measurements were reported:
- The Overall Response Rate (ORR) was observed in 2 Participants.
- The Disease Control Rate (DCR) was 45 percentage of participants, with a 95% Confidence Interval.
- The median Progression-Free Survival (PFS) was 2.4 months, with a 95% Confidence Interval.
- The median Overall Survival was 8.8 months, with a 95% Confidence Interval.
What this means
The results from this Phase 2 trial provide initial data on the activity of atezolizumab in combination with cobimetinib for advanced or refractory rare tumors, specifically highlighting outcomes for small bowel adenocarcinoma. The reported ORR, DCR, PFS, and OS figures offer insights into the potential of this combination therapy in a population with limited treatment options. These findings contribute to the understanding of therapeutic approaches for rare and difficult-to-treat cancers.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03108131, titled "Cobimetinib and Atezolizumab in Treating Participants With Advanced or Refractory Rare Tumors," were posted on 2025-05-28 on clinicaltrials.gov.