The following article features coverage from the ASCO Gastrointestinal Cancers Symposium 2021 meeting. Click here to read more of Cancer Therapy Advisor‘s conference coverage.

The combination of atezolizumab plus bevacizumab continues to demonstrate a clinically meaningful benefit in advanced hepatocellular carcinoma (HCC) vs sorafenib, according to updated overall survival (OS) data from the IMbrave150 study.1 “The median survival for atezolizumab plus bevacizumab is now over 19 months,” said Richard S. Finn, MD, of the Geffen School of Medicine at UCLA, who presented the findings at the 2021 Gastrointestinal Cancers Symposium. “This is the longest survival seen in a phase 3 study of advanced liver cancer.”

In the phase 3 IMbrave150 study (ClinicalTrials.gov identifier: NCT03434379), 501 patients were randomly assigned to receive atezolizumab plus bevacizumab or single-agent sorafenib. The primary analysis showed statistically significant (P <.001) and clinically meaningful improvements in OS and progression-free survival in the atezolizumab/bevacizumab arm at a median follow-up of 8.6 months.

The updated data, based on a median follow-up of 15.6 months, showed a median OS of 19.2 months with the combination (n=336) vs 13.2 months for sorafenib (n=165; HR, 0.66; 95% CI, 0.52-0.85; P =.0009). The median progression-free survival was 6.9 months for atezolizumab/bevacizumab compared with 4.3 months for sorafenib (HR, 0.65; 95% CI, 0.53-0.81; P =.0001).  “The curves separated early and remained separated throughout the course of the study,” Finn said.

Continue Reading

With longer follow-up, more responses with atezolizumab/bevacizumab were observed than initially reported, according to Finn. The confirmed overall response rate was 30%, which included more complete responses (CRs). The CR rate was 8.0% in the updated analysis vs 5.5% in the initial follow-up evaluation.2

The new data demonstrated a 74% disease control rate with atezolizumab/bevacizumab (vs 55% with sorafenib). The median duration of response with atezolizumab/bevacizumab was 18.1 months.1

Finn also presented results from a Chinese extension cohort that compared data on 133 patients who received atezolizumab/bevacizumab and 61 patients treated with sorafenib. The median OS was 24.0 months in the atezolizumab/bevacizumab group compared with 11.4 months in the sorafenib group (HR, 0.53; 95% CI, 0.35-0.80).

No new safety signals were observed over the course of the longer follow-up, Finn said.

Disclosures: Some of the study authors disclosed financial relationships with the pharmaceutical industry and/or the medical device industry. For a full list of disclosures, please refer to the original study. This clinical trial was supported by F Hoffmann-La Roche, Ltd.

Read more of Cancer Therapy Advisor‘s coverage of the ASCO GI 2021 meeting by visiting the conference page.


Reference

  1. Finn RS, Qin SQ, Ikeda M, et al. IMbrave150: updated overall survival (OS) data from a global, randomized, open-label phase III study of atezolizumab (atezo) + bevacizumab (bev) versus sorafenib (sor) in patients (pts) with unresectable hepatocellular carcinoma (HCC). Presented at: 2021 Gastrointestinal Cancers Symposium; January 15-17, 2021. Abstract 267.
  2. Finn RS, Qin S, Ikeda M, et al. Atezolizumab plus bevacizumab in unresectable hepatocellular carcinoma. N Engl J Med. 2020;382(20):1894-1905. doi:10.1056/NEJMoa1915745

Topics:

ASCO GI 2021 Gastrointestinal Cancer Hepatocellular Carcinoma