Sacituzumab govitecan (IMMU-132) in patients with previously treated metastatic urothelial cancer (mUC): Results from a phase I/II study

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Background: Patients (pts) with mUC who progress after platinum (PLT)-based chemotherapy and immune checkpoint inhibitor (CPI) therapy have poor outcomes and limited treatment options. Sacituzumab govitecan (SG) is a novel antibody-drug conjugate. It consists of a monoclonal antibody targeting Trop-2, an epithelial cell surface antigen overexpressed in UC, conjugated to the active metabolite of irinotecan (SN38). Methods: We performed a phase I/II basket study in pts with advanced solid tumors receiving intravenous SG administered on day 1 and 8 of 21-day cycles, until progression or unacceptable toxicity. CT/MRI scans were obtained at 8-week intervals for response assessment. We evaluated pts with mUC who progressed after ≥1 prior systemic therapy and were treated with SG at the 10 mg/kg dose level. Endpoints included safety, objective response rate (ORR) by RECIST 1.1, clinical benefit rate (CBR; complete response [CR], partial response [PR], or else SD ≥6-mo), and Kaplan-Meier estimated duration of response (DOR), progression-free survival (PFS), and overall survival (OS). Results: 45 pts (41M/4F; median age 67, range 49-90; ECOG 0/1: 31%/69%) received a median of 2 (range: 1-6) prior treatment lines, including PLT-based chemotherapy (95%) and CPI (38%). 33 had visceral metastases involving liver (n=15), lung (n=27), and other organs (n=5). The ORR was 31% (14/45), with 2 CR and 12 PR. In pts with visceral involvement, the ORR was 27% (9/33). The ORR in CPI-treated pts was 23% (4/17). The median DOR was 12.6 mo (2 pts continuing >2 y), and the CBR was 47% (21/45). Median PFS and OS were 7.3 mo and 18.9 mo, respectively. The AE profile was consistent with prior reports. Grade ≥3 AEs in ≥5% of pts were neutropenia/neutrophil count decreased (38%), anemia (11%), hypophosphatemia (11%), diarrhea (9%), fatigue (9%), and febrile neutropenia (7%). Conclusions: SG demonstrated clinical activity in pts with relapsed/refractory mUC, including CPI-treated pts and pts with visceral disease. A single-arm, open-label, global phase 2 trial is underway to evaluate antitumor activity and safety of SG in advanced UC.(TROPHY-U-01; NCT03547973). Clinical trial information: NCT03547973.

Phase II study of carboplatin, pemetrexed, and bevacizumab in advanced nonsquamous non-small-cell lung cancer

Lung cancer remains the leading cause of cancer death throughout the world. Despite new chemotherapeutic, immunomodulating and molecularly targeted agents, patients with locally advanced or metastatic disease still have a poor prognosis. This trial looked to combine antiangiogenic therapy with a first‐line cytotoxic chemotherapy doublet, hoping to extend median progression‐free survival (PFS) while minimizing toxicity in patients with advanced nonsquamous non–small‐cell lung cancer (NSCLC). In this single institution, single‐arm study, 51 patients (age >18 yo) were followed from 2007 to 2012. Patients with stage IV nonsquamous NSCLC and patients with recurrent unresectable disease (nonradiation candidates) were eligible. Treatment consisted of carboplatin AUC 5 IV 30‐60 minutes, pemetrexed 500/mg²IV 10 minutes, bevacizumab 15 mg/kg IV (90 minutes 1st dose, 60 minutes 2nd dose, 30 minutes subsequent doses). Treatment was administered every 21 days and planned for 6 cycles, in the absence of disease progression or unacceptable toxicities. Growth factor support was not permitted prophylactically but allowed for toxicities, as were dose reductions. Maintenance treatment for those with stable disease or better consisted of Bevacizumab 15 mg/kg every 3 weeks for up to 1 year. Between November 2007 and March 2012, 51 patients were followed in the phase II trial of carboplatin, pemetrexed, and bevacizumab. Patients were enrolled over a 24‐month period. After the end of treatment visits, subjects were followed at least every 3 months for survival data. The median follow‐up period was 49 weeks (6 weeks to 178), and the median number of treatment cycles was 6 (range, 1‐6). Among the 50 patients assessable for response, median overall survival was 49 weeks (95% CI, 0‐62.7) with median PFS of 28 weeks (95% CI, 0‐132.4). A complete or partial response was seen in 28 (59.5%) patients. Grade 3‐4 treatment‐related adverse events occurred in 9 (17.6%) of 51 patients; the most common were thrombocytopenia (4 [7.8%]) and neutropenia (3 [5.9%]). Three (5.8%) of 51 patients were discontinued because of treatment‐related adverse events (grade 3 diarrhea, thrombocytopenia, dehydration, fatigue, and grade 4 respiratory distress), and 1 patient (1.9%) was found to be ineligible due to anticoagulation use. A novel 3‐drug combination for advanced nonsquamous NSCLC shows promising efficacy with modest toxicity.

Phase I/II Trial of Labetuzumab Govitecan (Anti-CEACAM5/SN-38 Antibody-Drug Conjugate) in Patients With Refractory or Relapsing Metastatic Colorectal Cancer

Purpose The objectives were to evaluate dosing schedules of labetuzumab govitecan, an antibody-drug conjugate targeting carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) for tumor delivery of 7-ethyl-10-hydroxycamptothecin (SN-38), in an expanded phase II trial of patients with relapsed or refractory metastatic colorectal cancer. Patients and Methods Eligible patients with at least one prior irinotecan-containing therapy received labetuzumab govitecan once weekly at 8 and 10 mg/kg, or two times per week at 4 and 6 mg/km on weeks 1 and 2 of 3-week repeated cycles. End points were safety, response, pharmacokinetics, and immunogenicity. Results Eighty-six patients who had undergone a median of five prior therapies (range, one to 13) were each enrolled into one of the four cohorts. On the basis of Response Evaluation Criteria in Solid Tumors 1.1, 38% of these patients had a tumor as well as plasma carcinoembryonic antigen reduction from baseline after labetuzumab govitecan treatment; one patient achieved a partial response with a sustained response spanning > 2 years, whereas 42 patients had stable disease as the best overall response. Median progression-free survival and overall survival were 3.6 and 6.9 months, respectively. The major toxicities (grade ≥ 3) among all cohorts were neutropenia (16%), leukopenia (11%), anemia (9%), and diarrhea (7%). The antibody-drug conjugate's mean half-life was 16.5 hours for the four cohorts. Anti-drug/anti-antibody antibodies were not detected. The two once-weekly dose schedules, showing comparable toxicity and efficacy, were chosen for further study. Conclusion Monotherapy with labetuzumab govitecan demonstrated a manageable safety profile and therapeutic activity in heavily pretreated patients with metastatic colorectal cancer, all with prior irinotecan therapy. Further studies of labetuzumab govitecan treatment alone or in combination with other therapies in earlier settings are indicated.

Phase II trial of carboplatin, pemetrexed, and bevacizumab in metastatic nonsquamous (NSC) lung cancer

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Background: The trial was designed to examine PFS, OS and toxicities of a novel 3 drug combination in advanced NSC lung cancer. The first patient was entered 3/08 and the last in 5/11. Methods: Treatment consisted of Carboplatin AUC 5,Pemetrexed %00mg/m2, Bevacizumab 15mg/kg q21d x 6 cycles; then Bev maintenaince q3wk for up to one year. Eligibile pts. had metastatic non-squamous NSC lung ca, EGOG 0-1, first line Rx. Fifty patients were entered, all available for response and toxicity analysis: 26 M, median age 64, 45 white. Results: 52% RR by RECIST (2% CR, 50% PR); 26% SD. Median PFS 24 wks; median overall survival will be in excess of 49 weeks. 62% of patients received all planned 6 cycles and went on to maintenance. Treatment was out-patient and well tolerated with modest toxicities, including 2 DVT's, one PE, one TIA and one episode of F+N Conclusions: The 3 drug combination of Carboplatin, Pemetrxed and Bevacizumab for met NSC lung cancer is effective and well tolerated; and is a resonable choice of Rx for patients with non-squamous tumors hoping to avoid more neurotoxic or myelotoxic options.