Sacituzumab Govitecan in Previously Treated Patients With Metastatic NSCLC


Key Points

  • Sacituzumab govitecan produced responses in heavily pretreated patients with metastatic NSCLC, including those with prior immune checkpoint inhibitor therapy.
  • The level of Trop-2 expression did not appear to be predictive of response.

As reported by Heist et al in the Journal of Clinical Oncology, the antibody-drug conjugate sacituzumab govitecan showed activity in patients with previously treated metastatic non–small cell lung cancer (NSCLC). Sacituzumab targets Trop-2, present on many solid tumors; govitecan is the active metabolite of irinotecan.

Study Details

In the multicenter study, 54 patients received sacituzumab govitecan at 8 (n = 8) or 10 mg/kg (n = 46) on days 1 and 8 of 21-day cycles. The primary endpoints were safety and objective response rate.

Response Rates

Among 47 evaluable patients, who had a median of 3 prior therapies (range = 2–7), objective response (all partial responses) occurred in 9 patients (19%). The median response duration was 6.0 months. An additional 11 patients had stable disease for ≥ 4 months, yielding a clinical benefit rate of 43%. Among 14 patients who had received prior immune checkpoint inhibitor therapy, 2 (14%) had a response and 3 had stable disease ≥ 4 months, yielding a clinical benefit rate of 36%. Among all 54 patients, median progression-free survival was 5.2 months, and median overall survival was 9.5 months.

Among 26 evaluable archived tumor specimens, 24 (92%) were strongly or moderately positive for Trop-2 on immunohistochemistry, suggesting Trop-2 is not a biomarker of response.

Adverse Events

Grade ≥ 3 adverse events included neutropenia (28%), leukopenia (9%), pneumonia (9%), diarrhea (7%), nausea (7%), fatigue (6%), and febrile neutropenia (4%). One patient developed a transient immune response to the agent. Adverse events appeared to be similar at the two doses, except for an increase in grade 3 or 4 neutropenia at the higher dose (30% vs 13%). Adverse events led to drug discontinuation in two patients (grade 3 pneumonia and grade 3 recurrent pruritus).

The investigators concluded: “IMMU-132 [sacituzumab govitecan] was well tolerated and induced durable responses in heavily pretreated patients with metastatic NSCLC. This [antibody-drug conjugate] should be studied further in this disease and in other patients with Trop-2–expressing tumors.”

The study was supported by Immunomedics.

Rebecca Suk Heist, MD, MPH, of Massachusetts General Hospital, is the corresponding author of the Journal of Clinical Oncology article. 

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.