MORRIS PLAINS, N.J.—Immunomedics, Inc. reported today that the confirmatory Phase 3 ASCENT study of Trodelvy (sacituzumab govitecan-hziy) has met its primary endpoint of progression-free survival (PFS), as well as key secondary endpoints in brain metastasis negative patients with metastatic triple-negative breast cancer (mTNBC) who have previously received at least two prior therapies for metastatic disease.
Trodelvy — an antibody-drug conjugate directed against Trop-2, a cell-surface protein expressed in many solid cancers — binds to Trop-2 and delivers the anti-cancer drug SN-38 to kill cancer cells.
“The results of the global Phase 3 ASCENT study confirm our initial observations that sacituzumab govitecan has the potential to change the standard management of mTNBC. Based on these data, sacituzumab govitecan has set a new benchmark in scientific and clinical innovation for patients with mTNBC by offering a novel alternative to the common drugs currently in clinical practice,” stated Aditya Bardia, M.D., MPH, director of Precision Medicine at the Center for Breast Cancer, Massachusetts General Cancer Center and assistant professor of Medicine at Harvard Medical School, as well as the study’s principal investigator. “Importantly, the ASCENT topline data also validate the manageable safety profile of sacituzumab govitecan, rendering it a good partner candidate for combination with other therapies, including immunotherapy.”
In the ASCENT study, Trodelvy demonstrated a statistically significant improvement in the primary endpoint of PFS compared to chemotherapy, with a hazard ratio of 0.41 (95% confidence interval [CI], 0.32-0.52). The median PFS for patients treated with Trodelvy was 5.6 months (95% CI, 4.3-6.3), compared to 1.7 months (95% CI, 1.5-2.6) for chemotherapy. Trodelvy also met key secondary endpoints of the study, including overall survival and objective response rate.
The safety profile of Trodelvy observed in the ASCENT study remained consistent with the U.S. Food and Drug Administration (FDA)-approved label, with neutropenia and diarrhea as the most common Grade 3 or 4 adverse events. No new safety signals were observed.
“Given the poor prognosis associated with mTNBC, we are excited that Trodelvy demonstrated improved clinical outcomes for these patients,” added Dr. Loretta M. Itri, chief medical officer of Immunomedics. “We are grateful to all the patients, their families and healthcare providers, as well as our colleagues at Immunomedics, who participated in the ASCENT study and overcame many obstacles, including the COVID-19 pandemic, to complete the collection and analyses of these important data. We look forward to presenting full results at an upcoming medical conference, as well as sharing them with the FDA in support of the full approval of Trodelvy in this difficult-to-treat cancer.”
Immunomedics has an extensive development program for Trodelvy, including multiple ongoing studies in triple-negative breast cancer, metastatic urothelial cancer, hormone receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer, and metastatic non-small cell lung cancer — either as a monotherapy, or in combination with other agents.
Trodelvy was recently approved by the FDA as a third-line treatment for adult patients with mTNBC under the Accelerated Approval Program, based on the objective response rate and duration of response observed in a single-arm, multicenter Phase 2 study. The Phase 3 confirmatory ASCENT study was designed under an FDA Special Protocol Assessment to validate Trodelvy’s promising safety and efficacy activity, which supported its accelerated approval.
“It is gratifying to see the final confirmatory results of Trodelvy in a randomized study supporting the previously reported Phase 2 data that formed the basis of the accelerated approval of Trodelvy. These results provide important additional information for patients and their treating physicians to understand the definitive benefits they are deriving,” commented Dr. Behzad Aghazadeh, executive chairman of Immunomedics. “Importantly, the strong ASCENT data reinforce the promise of our unique ADC technology and embolden us to continue our work to change the treatment paradigm for patients with difficult-to-treat cancers.”