CA266-0004 ROSETTA Gastric-204
Research type
Research Study
Full title
CA266-0004: ROSETTA Gastric-204: A Blinded, Randomized, Phase 2/3 Study of Pumitamig in Combination with Chemotherapy Versus Nivolumab in Combination with Chemotherapy in Participants with Previously Untreated Advanced or Metastatic Gastric, Gastroesophageal Junction, or Esophageal Adenocarcinoma.
IRAS ID
1013196
Contact name
GSMCT Representative
Contact email
Sponsor organisation
Bristol-Myers Squibb Services Unlimited Company
Eudract number
2025-523263-37
Clinicaltrials.gov Identifier
Research summary
ROSETTA Gastric-204 is a global phase 2/3 clinical trial testing the safety and effectiveness of Pumitamig + chemotherapy compared to Nivolumab + chemotherapy in participants with previously untreated, HER2 negative, PD-L1 positive, advanced or metastatic gastric, gastroesophageal junction, or oesophageal cancer. Approx, 690 participants will take part in the study globally, including the UK.
The study has three parts (screening, treatment and follow-up) and two stages (phase 2 and phase 3). Phase 2 will compare how 2 different doses of Pumitamig affect the growth of the tumour to help select a better dose. Phase 3 will be reviewing if Pumitamig works better than current standard treatment and assess if people live longer when they take Pumitamig.
In the phase 2 study, 2 doses of Pumitamig will be compared against each other to find the optimal dose. Participants will be randomly assigned to one of the 3 groups: Arm A (Pumitamig at dose level 1 + chemotherapy), Arm B (Pumitamig at dose level 2 + chemotherapy), or control Arm C (Nivolumab + chemotherapy). Once enough participants have completed this phase to select the better Pumitamig dose, the study will move to Phase 3.
In the Phase 3 study, participants will be randomly assigned to one of 3 groups: Arm C (Pumitamig at the optimal dose chosen in the Phase 2 study + chemotherapy), or Arm D (Nivolumab + chemotherapy).Participants (18 years or older) will receive treatment until the cancer progress or side effects become too severe. After stopping treatment, participants will be monitored in-person for side effects for about 90 days and then contacted remotely about every 12 weeks for long-term follow-up. Total study duration is expected to be approx. 17 months for a participant.
REC name
South Central - Berkshire Research Ethics Committee
REC reference
25/SC/0377
Date of REC Opinion
19 Dec 2025
REC opinion
Further Information Favourable Opinion