Innovent Biologics released the final data analysis of a Phase III trial investigating sintilimab in advanced or metastatic gastric or gastroesophageal junction (G/GEJ) cancer.

Sintilimab, marketed as Tyvyt in China, was studied in combination with Roche’s chemotherapy Xeloda (capecitabine) and compared to Xeloda alone.

Sintilimab, which is co-developed by Innovent and Eli Lilly, is a G4 monoclonal antibody that binds to PD-1 molecules and blocks the PD-1/PD-L1 pathway.

The results were presented at the American Association for Cancer Research (AACR) Annual Meeting 2023. The final analysis showed that sintilimab demonstrated a significant overall survival (OS) benefit in patients with advanced G/GEJ cancer when treated in combination with chemotherapy as a first line of treatment.

OS was measured as a primary endpoint in a 650-patient Phase III trial (NCT03745170).

Final data in a Phase III ESCC trial

At AACR, Innovent also presented final data from a Phase III trial investigating sintilimab with chemotherapy as a first line of treatment compared to chemotherapy alone in patients with oesophagal squamous cell carcinoma (ESCC).

As of the cut-off date on 28 August 2022, the Phase III trial (NCT03748134) had randomised 690 patients with unresectable, locally advanced recurrent or metastatic ESCC into treatment and active comparator arms. The median follow-up was 32.2 months.

The final data analysis showed that the sintilimab and chemotherapy combination improved the median OS (mOS) with a 33.9% death risk reduction and a 4.6-month improvement in mOS in all randomised patients. A 36.5% reduction in risk of death and 3.9-month mOS improvement were observed in PD-L1 positive patients. The primary endpoints of the trial measured OS in all randomised and PD-L1-positive patients.

Phase I in advanced solid tumours

Innovent also released updated data from a Phase I trial investigating IBI351 in patients with advanced solid tumours who failed or are intolerant to a standard of care treatment. IBI351 is a KRAS G12C mutation inhibitor.

As of the cut-off date on 30 November 2022, 74 participants were enrolled in the study. 67 of the enrolled patients have non-small cell lung cancer (NSCLC), with 38.8% of brain metastases cases at baseline while six patients have colorectal cancer (CRC) and one has pancreatic cancer.

As of 10 February 2023, 41 NSCLC patients achieved partial response, with an objective response rate (ORR) measured at 61.2%, and a 92.5% disease control rate (DCR).

IBI351 was well tolerated, and no dose-limiting toxicities (DLTs) were reported, as of 30 November 2022. Treatment-related adverse events (TRAEs) were observed in 94% of patients and the most commonly reported TREAs were anaemia, pruritus, increased transferase, asthenia, present protein in urine, and increased bilirubin.