Overall survival with sacituzumab govitecan in hormone receptor-positive and human epidermal growth factor receptor 2-negative metastatic breast cancer (TROPiCS-02): a randomised, open-label, multicentre, phase 3 trial

BACKGROUND

Sacituzumab govitecan demonstrated significant progression-free survival benefit over chemotherapy in the phase 3 TROPiCS-02 trial in patients with pretreated, endocrine-resistant hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+ and HER2-) metastatic breast cancer with limited treatment options. Here, we report the protocol-specified final analysis of overall survival and endpoints by trophoblast cell-surface antigen 2 (Trop-2) expression and other variables.

METHODS

In this randomised, open-label, multicentre, phase 3 trial, which took place in 91 centres across North America (the USA and Canada) and Europe (Belgium, France, Germany, Italy, the Netherlands, Spain, and the UK), patients were randomly assigned (1:1) to receive sacituzumab govitecan or chemotherapy (eribulin, vinorelbine, capecitabine, or gemcitabine). Patients had confirmed HR+ and HER2- locally recurrent inoperable or metastatic breast cancer and had received at least one previous endocrine therapy, a taxane, and a CDK4/6 inhibitor in any setting and two to four previous chemotherapy regimens for metastatic disease. The primary endpoint was progression-free survival (previously reported and not included in this analysis), and secondary endpoints included overall survival, objective response rate (ORR), and patient-reported outcomes. Overall survival was assessed using stratified log-rank tests and Cox regression. Trop-2 expression was assessed in tumour tissue by immunohistochemistry. In the statistical testing hierarchy, ORR and patient-reported outcomes were tested sequentially if overall survival was significant. This study is registered with ClinicalTrials.gov, NCT03901339.

FINDINGS

At the data cutoff date of July 1, 2022, 543 of 776 screened patients were randomly assigned between May 30, 2019, and April 5, 2021, with 272 patients in the sacituzumab govitecan group and 271 patients in the chemotherapy group. With a 12·5-month (IQR 6·4-18·8) median follow-up, 390 deaths occurred among 543 patients. Overall survival was significantly improved with sacituzumab govitecan versus chemotherapy (median 14·4 months [95% CI 13·0-15·7] vs 11·2 months [10·1-12·7]; hazard ratio [HR] 0·79, 95% CI 0·65-0·96; p=0·020); survival benefit was consistent across Trop-2 expression-level subgroups. ORR was significantly improved with sacituzumab govitecan compared with chemotherapy (57 [21%] patients vs 38 [14%]; odds ratio 1·63 [95% CI 1·03-2·56]; p=0·035), as was time to deterioration of global health status and quality of life (median 4·3 months vs 3·0 months; HR 0·75 [0·61-0·92]; p=0·0059) and fatigue (median 2·2 months vs 1·4 months; HR 0·73 [0·60-0·89]; p=0·0021). The safety profile of sacituzumab govitecan was consistent with previous studies (including the TROPiCS-02 primary analysis and the ASCENT trial). One fatal adverse event (septic shock caused by neutropenic colitis) was determined to be related to sacituzumab govitecan treatment.

INTERPRETATION

Sacituzumab govitecan demonstrated statistically significant and clinically meaningful benefit over chemotherapy, with a 3·2-month median overall survival improvement and a manageable safety profile. These data support sacituzumab govitecan as a new treatment option for patients with pretreated, endocrine-resistant HR+ and HER2- metastatic breast cancer.

FUNDING

Gilead Sciences.

Abstract GS1-11: Sacituzumab Govitecan (SG) vs Treatment of Physician’s Choice (TPC): Efficacy by Trop-2 Expression in the TROPiCS-02 Study of Patients (Pts) With HR+/HER2– Metastatic Breast Cancer (mBC)

Background: HR+/HER2– mBC, the most common subset of breast cancer, is treated with sequential endocrine therapy + targeted agents followed by sequential single-agent chemotherapy (CT), with increasingly shorter benefit duration with each subsequent treatment. High Trop-2 expression is observed in breast cancer regardless of subtype. SG is a Trop-2-directed antibody-drug conjugate approved for pre-treated metastatic triple-negative breast cancer. In the phase 3 TROPiCS-02 study, SG showed both significant progression-free survival (PFS) benefit (HR, 0.66; P<0.001; median 5.5 vs 4.0 mo; JCO 2022) at the primary analysis and overall survival (OS) benefit (median 14.4 vs 11.2 mo; HR, 0.79; P=0.02; ESMO 2022) at the 2nd planned interim OS analysis vs TPC in pretreated HR+/HER2- mBC. Here we compare efficacy outcomes for SG and TPC by Trop-2 expression. Methods: Eligible pts had HR+/HER2- locally recurrent inoperable or mBC; received ≥1 prior taxane, endocrine therapy, a CDK4/6 inhibitor; and received 2-4 prior CT regimens for mBC. Pts were randomized 1:1 to receive SG (10 mg/kg IV on d 1 and 8, every 21 d) or TPC (eribulin, gemcitabine, capecitabine, or vinorelbine) until disease progression or unacceptable toxicity. The primary endpoint was PFS by independent review per RECIST v1.1; OS and objective response rate (ORR) were key secondary endpoints. ORR was assessed by blinded independent central review per RECIST v1.1. Membrane Trop-2 expression on archival tumor tissue was assessed by immunohistochemistry and expressed as a histochemical score (H-score; range, 0-300); efficacy outcomes were assessed in H-score <100 and ≥100 groups. The H-score <100 group was further divided into H-score ≤10 and >10- <100 subgroups to assess the activity of SG in pts with very low Trop-2 expression. Results: Data cut-off was January 3, 2022 for PFS (median follow-up, 10.2 mo) and July 1, 2022 for OS (median follow-up, 12.5 mo). In total, 543 pts were randomized to receive SG (n=272) vs TPC (n=271). Pts had a median of 3 prior CT regimens for mBC; 95% had visceral metastases. There were 238 (88%) vs 224 (83%) Trop-2-evaluable pts in the SG vs TPC groups, respectively; of these, 95% had tumors with Trop-2 H-score >0. Of Trop-2-evaluable pts, 192 (42%) and 270 (58%) had H-scores <100 and ≥100, respectively. Demographics and baseline characteristics were generally consistent across H-score groups. PFS and OS benefit was observed for SG vs TPC across both Trop-2 groups (Table). Median PFS was 5.3 vs 4.0 mo (HR, 0.77; 95% CI, 0.54-1.09) and 6.4 vs 4.1 mo (HR, 0.60; 95% CI, 0.44-0.81) in the H-score <100 and ≥100 groups; median OS was 14.6 vs 11.3 mo (HR, 0.75; 95% CI, 0.54-1.04) and 14.4 vs 11.2 mo (HR, 0.83; 95% CI, 0.62-1.11), respectively. Disease response was observed in the 34 pts with H-score ≤10 who received SG. In pts who received SG, those with H-score ≤10, >10- <100, and ≥100 had ORRs of 24%, 18%, and 23%, respectively. The safety profile for SG by Trop-2 H-score was consistent with previous reports. Conclusions: In this TROPiCS-02 post-hoc analysis, improved efficacy with SG vs TPC was observed regardless of Trop-2 expression, and there was no clear level of Trop-2 expression at which a better treatment effect for SG was observed. These results support SG as an effective novel treatment option for patients with pretreated, endocrine-resistant HR+/HER2- mBC, and reinforce that Trop-2 testing is not required for SG treatment.

Table

Citation Format: Hope Rugo, Aditya Bardia, Frederik Marmé, Javier Cortés, Peter Schmid, Delphine Loirat, Olivier Trédan, Eva Ciruelos, Florence Dalenc, Patricia Gómez Pardo, Komal Jhaveri, Monica Motwani, Oh Kyu Yoon, Hao Wang, Wendy Verret, Sara Tolaney. Sacituzumab Govitecan (SG) vs Treatment of Physician’s Choice (TPC): Efficacy by Trop-2 Expression in the TROPiCS-02 Study of Patients (Pts) With HR+/HER2– Metastatic Breast Cancer (mBC) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS1-11.

Abstract P3-07-08: Exposure-adjusted incidence rates (EAIRs) of adverse events (AEs) from the phase 3 TROPiCS-02 study of sacituzumab govitecan (SG) vs treatment of physician’s choice (TPC) in HR+/HER2- metastatic breast cancer (MBC)

Background: SG is a Trop-2-directed antibody-drug conjugate approved by the FDA for patients (pts) with metastatic triple-negative breast cancer who received ≥2 prior chemotherapies (≥1 for MBC). In the phase 3 TROPiCS-02 study, SG demonstrated a 34% reduction in risk of progression or death vs TPC in heavily pretreated, endocrine-resistant HR+/HER2– MBC (Rugo H, et al. ASCO 2022. LBA1001). The safety profile was manageable, with neutropenia and diarrhea as the key AEs. Absolute incidence rate is the most used metric to summarize AEs in routine clinical safety analyses. However, when the treatment duration differs significantly between treatment arms, these rates may need adjustment to account for longer treatment exposure, which may incur a higher incidence of AEs. Given that the median treatment duration was longer for SG in TROPiCS-02, EAIRs were assessed in post hoc safety analyses.

Methods: Pts with HR+/HER2– unresectable locally advanced or MBC and 2-4 prior chemotherapy regimens for MBC were randomized 1:1 to receive SG or TPC (capecitabine, eribulin, vinorelbine, or gemcitabine) until unacceptable toxicity or disease progression. The primary endpoint was progression-free survival per RECIST 1.1 by central review. Safety was a secondary endpoint. Time-at-risk EAIR considers pts’ exposure of a specific AE in quantifying the risk of AE, defined as the number of pts who experienced at least 1 specific AE, divided by the total exposure time (pt-year of exposure [PYE]) in each arm. For pts who experienced specific AEs, exposure time was calculated from first dose date up to the first AE onset, and for pts who did not, from first dose up to data cutoff (if still on study treatment) or up to last dose (if discontinued study treatment). The 95% CI of the EAIR difference is a standard method to assess the statistical significance of AE incidence rate differences between arms.

Results: Of 543 pts enrolled (median age, 56 y; visceral metastases, 95%; prior CDK4/6 inhibitor for MBC, 99%; median lines of chemotherapy for MBC, 3), 517 pts (SG, n=268; TPC, n=249) received ≥1 dose of study treatment. At data cutoff (Jan 3, 2022), 18 pts (7%) vs 4 pts (2%) remained on treatment in the SG vs TPC arms; median treatment duration was 4.1 months and 2.3 months, respectively. The absolute incidence, EAIRs (incidence per 1 PYE), and EAIR differences for the overall safety summary and most common grade ≥3 TEAEs are provided (Table). Overall, SG had higher absolute incidence rates vs TPC for grade ≥3 treatment-emergent AEs (TEAEs), serious AEs, and TEAEs leading to death, but the EAIRs were similar between arms, suggesting an association with duration of treatment exposure. When adjusted for exposure, the incidence of grade ≥3 diarrhea remained higher for SG vs TPC; however, the incidence of grade ≥3 neutropenia was similar between arms.

Conclusions: The safety profile of SG was manageable in pts with heavily pretreated HR+/HER2– endocrine-resistant, unresectable locally advanced or MBC. Though there was a higher absolute incidence of TEAEs leading to death and grade ≥3 neutropenia with SG vs TPC, the EAIRs were similar. Taken together with the efficacy benefit with SG, this supports a favorable risk/benefit profile for SG compared with standard chemotherapy in this pt population with limited therapeutic options.

Table. Overall Safety Summary and Summary of Common (Absolute Incidence ≥5%) Grade ≥3 TEAEs With Absolute Incidence, Exposure-Adjusted Incidence Rates (EAIRs),a and EAIR Differencesb,c

Citation Format: Sara Tolaney, Peter Schmid, Aditya Bardia, Frederik Marmé, Delphine Loirat, Priyanka Sharma, Hao Wang, Olivia Fu, Wendy Verret, Hope Rugo. Exposure-adjusted incidence rates (EAIRs) of adverse events (AEs) from the phase 3 TROPiCS-02 study of sacituzumab govitecan (SG) vs treatment of physician’s choice (TPC) in HR+/HER2- metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-07-08.

Abstract P4-07-65: Effect of sacituzumab govitecan vs chemotherapy in HR+/HER2- metastatic breast cancer: patient-reported outcomes from the TROPiCS-02 trial

Background: For HR+/HER2- metastatic breast cancer (MBC) patients, after resistance to endocrine therapy (ET), treatment options are mostly limited to traditional chemotherapies (CT) that offer poor survival and quality of life (QoL), creating an area of unmet need. The antibody-drug conjugate sacituzumab govitecan (SG) comprises an anti-Trop-2 antibody coupled to SN-38 via a hydrolyzable linker. In the phase 3 TROPiCS-02 trial, heavily pretreated patients with relapsed/refractory HR+/HER2- MBC received SG vs single-agent chemotherapy treatment of physician’s choice (TPC). The study met its primary endpoint of improved progression-free survival with SG vs TPC. Here, we report the effect of SG vs TPC on patient-reported outcomes (PROs) from TROPiCS-02.

Patients and Methods: Patients who had received ≥1 CDK 4/6 inhibitor, ≥1 ET, and 2-4 prior lines of CT were randomized to receive SG (10 mg/kg intravenous on days 1 and 8 of a 21-day treatment cycle) or TPC (capecitabine, eribulin, gemcitabine, or vinorelbine). In the PRO-evaluable population (all randomized patients with an evaluable assessment at baseline (BL) and ≥1 post-BL visit) SG and TPC were compared regarding time to first clinically meaningful worsening (TTD) or death from BL on the EORTC QLQ-C30 domains (≥10 points), EQ-5D-5L health utility index (≥0.08 points), and EQ-VAS (≥7 points). For the EORTC QLQ-C30 function and global health status/QoL domains, patients with a BL score ≥10 and for symptom scales, patients with a BL score ≤90 were included. In the safety population (all randomized patients who received ≥1 dose of study drug), SG and TPC were compared regarding worst level of toxicities during treatment for the PRO-CTCAE items. For TTD, a stratified Cox proportional hazards regression analysis was conducted and the PRO-CTCAE items were summarized descriptively (numbers and percentages).

Results: Of 543 randomized patients, 446 (82%), 445 (82%), and 517 (95%) were included in the PRO-evaluable population (EORTC QLQ-C30: SG vs TPC n=236 vs 210 and EQ-5D-5L: n=238 vs 207) and in the safety population for PRO-CTCAE (SG vs TPC n=268 vs 249), respectively. TTD of EORTC QLQ-C30 global health status/QoL, physical functioning, emotional functioning, fatigue, dyspnea, insomnia, and financial difficulties and EQ-VAS were significantly longer in the SG vs the TPC arm (Table). TTD of EORTC QLQ-C30 diarrhea was significantly shorter for SG vs TPC. For PRO-CTCAE items, decreased appetite, nausea, vomiting, constipation, abdominal pain, shortness of breath, and fatigue were similar between SG and TPC arms, whereas frequency of diarrhea and amount of hair loss were higher in the SG vs TPC arm.

Conclusions: In this trial, SG significantly delayed worsening of overall QoL, physical and emotional functioning, and symptoms like fatigue, dyspnea, and insomnia. Overall, our findings suggest that SG has more favorable effects on PROs compared with TPC in pts with HR+/HER2- MBC.

Table: Time to First Clinically Meaningful Deterioration PRO Scores

Citation Format: Frederik Marmé, Aditya Bardia, Hope Rugo, Peter Schmid, Sara M. Tolaney, Mafalda Oliveira, Andreas Schneeweiss, Ling Shi, Wendy Verret, Mahdi Gharaibeh, Anju Shah, Javier Cortés. Effect of sacituzumab govitecan vs chemotherapy in HR+/HER2- metastatic breast cancer: patient-reported outcomes from the TROPiCS-02 trial [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-07-65.

Sacituzumab Govitecan in Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Metastatic Breast Cancer

PURPOSE

Hormone receptor-positive (HR+) human epidermal growth factor receptor 2-negative (HER2-) endocrine-resistant metastatic breast cancer is treated with sequential single-agent chemotherapy with poor outcomes. Sacituzumab govitecan (SG) is a first-in-class antibody-drug conjugate with an SN-38 payload targeting trophoblast cell-surface antigen 2, an epithelial antigen expressed in breast cancer.

METHODS

In this global, randomized, phase III study, SG was compared with physician's choice chemotherapy (eribulin, vinorelbine, capecitabine, or gemcitabine) in endocrine-resistant, chemotherapy-treated HR+/HER2- locally recurrent inoperable or metastatic breast cancer. The primary end point was progression-free survival (PFS) by blinded independent central review.

RESULTS

Patients were randomly assigned to receive SG (n = 272) or chemotherapy (n = 271). The median age was 56 years, 95% had visceral metastases, and 99% had a prior cyclin-dependent kinase 4/6 inhibitor, with three median lines of chemotherapy for advanced disease. Primary end point was met with a 34% reduction in risk of progression or death (hazard ratio, 0.66 [95% CI, 0.53 to 0.83; P = .0003]). The median PFS was 5.5 months (95% CI, 4.2 to 7.0) with SG and 4.0 months (95% CI, 3.1 to 4.4) with chemotherapy; the PFS at 6 and 12 months was 46% (95% CI, 39 to 53) v 30% (95% CI, 24 to 37) and 21% (95% CI, 15 to 28) v 7% (95% CI, 3 to 14), respectively. Median overall survival (first planned interim analysis) was not yet mature (hazard ratio, 0.84; P = .14). Key grade ≥ 3 treatment-related adverse events (SG v chemotherapy) were neutropenia (51% v 38%) and diarrhea (9% v 1%).

CONCLUSION

SG demonstrated statistically significant PFS benefit over chemotherapy, with a manageable safety profile in patients with heavily pretreated, endocrine-resistant HR+/HER2- advanced breast cancer and limited treatment options.

Atezolizumab plus Bevacizumab versus Sorafenib for Unresectable Hepatocellular Carcinoma: Results from Older Adults Enrolled in the IMbrave150 Randomized Clinical Trial

INTRODUCTION

The efficacy of systemic first-line treatments in older adults with unresectable hepatocellular carcinoma (HCC) has not been well-studied. We compared the safety and efficacy of atezolizumab plus bevacizumab versus sorafenib as a first-line treatment in younger versus older patients with unresectable HCC.

METHODS

This global, phase 3, open-label, randomized clinical trial (IMbrave150) recruited patients aged ≥18 years with locally advanced metastatic or unresectable HCC, an Eastern Cooperative Oncology Group performance status score of 0 or 1, and Child-Pugh class A liver function who had not previously received systemic therapy for liver cancer. Patients received either 1,200 mg atezolizumab plus 15 mg/kg bevacizumab intravenously every 3 weeks or 400 mg sorafenib orally twice daily until loss of clinical benefit or unacceptable toxicity. Primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary outcomes were the incidence of adverse events and time to deterioration of patient-reported outcomes (PROs). This subgroup analysis evaluated safety and efficacy endpoints in patients <65 years, ≥65 to <75 years, and ≥75 years.

RESULTS

Of 501 patients, 165 patients were randomized to sorafenib and 336 were randomized to atezolizumab plus bevacizumab (175 patients <65 years; 106 patients ≥65 to <75 years; 55 patients ≥75 years). Across all age groups, patients receiving atezolizumab plus bevacizumab had longer median OS (<65: 18.0 vs. 12.2 months [HR, 0.57; 95% CI: 0.40-0.82]; ≥65 to <75: 19.4 vs. 14.9 months [HR, 0.80; 95% CI: 0.52-1.23]; ≥75: 24.0 vs. 18.0 months [HR, 0.72, 95% CI: 0.37-1.41]) and PFS than those receiving sorafenib. Time to deterioration for multiple PROs was delayed for patients receiving atezolizumab plus bevacizumab, including older adults. There were no clinically meaningful differences in toxicity between age groups.

CONCLUSION

Atezolizumab plus bevacizumab is safe and effective in adults <65, ≥65 to <75, and ≥75. Treatment was well-tolerated even in elderly patients.

Primary results from TROPiCS-02: A randomized phase 3 study of sacituzumab govitecan (SG) versus treatment of physician’s choice (TPC) in patients (Pts) with hormone receptor–positive/HER2-negative (HR+/HER2-) advanced breast cancer

LBA1001

Background: HR+/HER2– disease is the most common subtype of metastatic breast cancer (MBC). Treatment includes sequential endocrine therapy combined with targeted agents followed by single-agent chemotherapy, with increasingly shorter durations of benefit. SG is an anti–Trop-2 antibody-drug conjugate approved for metastatic triple-negative breast cancer with ≥2 prior therapies (≥1 for MBC). The HR+/HER2– MBC cohort of the phase 1/2 IMMU-132-01 study (n = 54) had an objective response rate (ORR) of 31.5%, median progression-free survival (PFS) of 5.5 mo, median overall survival (OS) of 12 mo, and a manageable safety profile with SG. TROPiCS-02 is a phase 3 randomized study (NCT03901339) to confirm SG outcomes in HR+/HER2– advanced breast cancer. Methods: Adults with locally determined, HR+/HER2– unresectable locally advanced or MBC, ECOG performance status of 0 or 1, and 2-4 prior chemotherapy regimens for MBC were eligible; 1 prior therapy for MBC was allowed if disease progressed ≤12 mo after (neo)adjuvant therapy. Pts must have received ≥1 prior taxane, CDK4/6 inhibitor, and endocrine therapy in any setting. Pts were randomized 1:1 to receive SG (10 mg/kg IV on d1 and 8, every 21d) or TPC (capecitabine, eribulin, vinorelbine, or gemcitabine) until disease progression/unacceptable toxicity. Primary endpoint was PFS per RECIST v1.1 by blinded independent central review (final analysis) with key secondary endpoint of OS (1st planned interim analysis). Results: At data cutoff on Jan 3, 2022, 272 vs 271 pts were randomized to receive SG vs TPC, respectively. Pt characteristics in the SG vs TPC arms were similar (3 median prior chemotherapy regimens for MBC [range, 0-8]; 95% had visceral metastases, 86% had prior endocrine therapy for MBC for ≥6 mo, 60% and 38% received prior CDK4/6 inhibitors for ≤12 and > 12 mo, respectively). SG (vs TPC) improved median PFS (5.5 vs 4.0 mo; HR, 0.66; 95% CI, 0.53-0.83; P= 0.0003); PFS rates at 6 and 12 mo were 46% vs 30% and 21% vs 7%, respectively. SG vs TPC showed a numeric but nonsignificant difference in OS (13.9 vs 12.3 mo; HR, 0.84; P= 0.143); ORR (21% vs 14%) and clinical benefit rate (34% vs 22%) were higher with SG vs TPC and median duration of response was 7.4 vs 5.6 mo, respectively. Overall, 74% vs 60% of patients (SG vs TPC) had grade ≥3 treatment-emergent adverse events (AEs); neutropenia (51% vs 39%) and diarrhea (10% vs 1%) were most common. AEs leading to discontinuation of SG vs TPC were low (6% vs 4%). There was 1 treatment-related death in the SG arm; none in the TPC arm. Conclusions: SG had a statistically significant, clinically meaningful PFS benefit over single-agent chemotherapy and a manageable safety profile in pts with heavily pre-treated HR+/HER2– endocrine-resistant, unresectable locally advanced or MBC, who have limited treatment options. Clinical trial information: NCT03901339.

Updated efficacy and safety data from IMbrave150: Atezolizumab plus bevacizumab vs. sorafenib for unresectable hepatocellular carcinoma

BACKGROUND & AIMS

IMbrave150 demonstrated that atezolizumab plus bevacizumab led to significantly improved overall survival (OS) and progression-free survival (PFS) compared with sorafenib in patients with unresectable hepatocellular carcinoma at the primary analysis (after a median 8.6 months of follow-up). We present updated data after 12 months of additional follow-up.

METHODS

Patients with systemic treatment-naive, unresectable hepatocellular carcinoma were randomized 2:1 to receive 1,200 mg atezolizumab plus 15 mg/kg bevacizumab intravenously every 3 weeks or 400 mg sorafenib orally twice daily in this open-label, phase III study. Co-primary endpoints were OS and PFS by independently assessed RECIST 1.1 in the intention-to-treat population. Secondary efficacy endpoints included objective response rates and exploratory subgroup efficacy analyses. This is a post hoc updated analysis of efficacy and safety.

RESULTS

From March 15, 2018, to January 30, 2019, 501 patients (intention-to-treat population) were randomly allocated to receive atezolizumab plus bevacizumab (n = 336) or sorafenib (n = 165). On August 31, 2020, after a median 15.6 (range, 0-28.6) months of follow-up, the median OS was 19.2 months (95% CI 17.0-23.7) with atezolizumab plus bevacizumab and 13.4 months (95% CI 11.4-16.9) with sorafenib (hazard ratio [HR] 0.66; 95% CI 0.52-0.85; descriptive p <0.001). The median PFS was 6.9 (95% CI 5.7-8.6) and 4.3 (95% CI 4.0-5.6) months in the respective treatment groups (HR 0.65; 95% CI 0.53-0.81; descriptive p < 0.001). Treatment-related grade 3/4 adverse events occurred in 143 (43%) of 329 and 72 (46%) of 156 safety-evaluable patients in the respective groups, and treatment-related grade 5 events occurred in 6 (2%) and 1 (<1%) patients.

CONCLUSION

After longer follow-up, atezolizumab plus bevacizumab maintained clinically meaningful survival benefits over sorafenib and had a safety profile consistent with the primary analysis.

GOV IDENTIFIER

NCT03434379.

LAY SUMMARY

The primary analysis of IMbrave150 showed that atezolizumab plus bevacizumab had significantly greater benefits than sorafenib in patients with advanced hepatocellular carcinoma, but survival data were not yet mature. At this updated analysis done 12 months later, median overall survival was 5.8 months longer with atezolizumab plus bevacizumab than sorafenib, and the severity profile of treatment-related side effects remained similar. These updated results confirm atezolizumab plus bevacizumab as the first-line standard of care for advanced hepatocellular carcinoma.

Serum IGF-1 Scores and Clinical Outcomes in the Phase III IMbrave150 Study of Atezolizumab Plus Bevacizumab versus Sorafenib in Patients with Unresectable Hepatocellular Carcinoma

PURPOSE

Child-Turcotte-Pugh class A (CTP-A) in unresectable hepatocellular carcinoma (HCC) is the standard criterion for active therapy and clinical trial enrollment. We hypothesized that insulin-like growth factor-1 (IGF-1) derived scores may provide improved survival prediction over CTP classification. This study aimed to evaluate the potential prognostic and predictive effects of IGF-1 derived scores in the phase III IMbrave150 study.

PATIENTS AND METHODS

Baseline and on-treatment serum IGF-1 levels from 371 patients were subjected to central analysis. Patients' IGF-1 score (1/2/3) and IGF-CTP score (A/B/C) were determined based on pre-specified cutoffs. Outcomes were analyzed by baseline and by on-treatment changes of the IGF-1 and IGF-CTP scores within and between the two treatment arms. The interaction between these scores and outcomes was assessed using univariate and multivariate analyses.

RESULTS

Baseline IGF-CTP score (A vs B/C) showed prognostic significance for OS in both the atezolizumab-bevacizumab (hazard ratio [HR], 0.33; 95% confidence interval [CI], 0.20-0.56; P<0.001) and sorafenib (HR, 0.32; 95% CI, 0.16-0.65; P=0.002) arms. Baseline IGF-1 score (1 vs 2/3) also showed prognostic significance for OS in both the atezolizumab-bevacizumab (HR, 0.33; 95% CI, 0.20-0.55; P<0.001) and sorafenib (HR, 0.48; 95% CI, 0.26-0.89; P=0.02) arms. HRs for PFS were consistent with those for OS. No significant predictive effects were observed for either score between the two arms. Kinetic analysis revealed that patients with increased IGF-1 score (1-> 2/3) at 3 weeks post treatment had shorter OS than patients with stable IGF-1 score of 1 in both the atezolizumab-bevacizumab (HR, 3.70; 95% CI, 1.56-8.77; P=0.003) and sorafenib (HR, 5.83; 95% CI, 1.88-18.12; P=0.0023) arms.

CONCLUSION

Baseline and kinetic change of IGF-CTP and IGF-1 scores are independent prognostic factors for patients with unresectable HCC treated with atezolizumab-bevacizumab or sorafenib. These novel scores may provide improved patient stratification in future HCC clinical trials. IMbrave150 ClincialTrials.gov number, NCT03434379.

IMbrave 151: a randomized phase II trial of atezolizumab combined with bevacizumab and chemotherapy in patients with advanced biliary tract cancer

Background:

Biliary tract cancers (BTCs) are heterogenous, highly aggressive tumors that harbor a dismal prognosis for which more effective treatments are needed. The role of cancer immunotherapy in BTC remains to be characterized. The tumor microenvironment (TME) of BTC is highly immunosuppressed and combination treatments are needed to promote effective anticancer immunity. Vascular endothelial growth factor (VEGF) drives immunosuppression in the TME by disrupting antigen presentation, limiting T-cell infiltration, or potentiating immune-suppressive cells. Many VEGF-regulated mechanisms are thought to be relevant to repressed antitumor immunity in BTC, making dual targeting of VEGF and programmed cell death protein 1 (PD-1)/PD-L1 pathways a rational approach. Gemcitabine and Cisplatin (Gem/Cis) can also modulate anticancer immunity through overlapping and complementary mechanisms to those regulated by VEGF. Anti-PD-L1/VEGF inhibition, coupled with chemotherapy, may potentiate antitumor immunity leading to enhanced clinical benefit.

Methods:

IMbrave 151 is a randomized, double-blind, placebo-controlled, multicenter, international phase II study to evaluate atezolizumab (a PD-L1 inhibitor) in combination with chemotherapy (gemcitabine and cisplatin) and bevacizumab (an anti-VEGF monoclonal antibody) as a first-line treatment for advanced BTC. Approximately 150 patients with previously untreated, advanced BTC will be randomized to either Arm A (atezolizumab + bevacizumab + Gem/Cis) or Arm B (atezolizumab + placebo + Gem/Cis). Randomization is stratified by the presence of metastatic disease, primary tumor location, and geographic region. The primary efficacy endpoint is investigator-assessed progression-free survival (PFS) per RECIST 1.1. Secondary endpoints include objective response rate (ORR), duration of response (DoR), disease control rate (DCR), overall survival (OS), and safety and patient reported outcomes (PROs). Tissue, blood, and stool samples will be collected at baseline and on-treatment in order to perform correlative biomarker analyses.

Discussion:

IMbrave 151 represents the first randomized study to evaluate combined PD-L1/VEGF blockade on a chemotherapy backbone in BTC.

Trial registration:

NCT identifier: NCT04677504; EUDRACT number: 2020-003759-14

Abstract CT009: IMbrave150: Updated efficacy and safety by risk status in patients (pts) receiving atezolizumab (atezo) + bevacizumab (bev) vs sorafenib (sor) as first-line treatment for unresectable hepatocellular carcinoma (HCC)

Background: Based on the Ph III IMbrave150 trial, atezo + bev has been approved globally and is the standard of care for pts with unresectable HCC who have not received prior systemic therapy. With an additional 12 mo of follow-up from the primary analysis (median, 15.6 mo), atezo + bev showed consistent clinically meaningful treatment benefit and safety (Finn ASCO GI 2021). Here, we report results of updated analyses considering high-risk factors. Methods: Pts were randomized 2:1 to receive atezo 1200 mg IV q3w + bev 15 mg/kg IV q3w or sor 400 mg PO BID until loss of clinical benefit or unacceptable toxicity. High-risk pts were defined as those who had tumor invasion of the main trunk of the portal vein and/or the portal vein branch contralateral to the primarily involved lobe (Vp4), and/or bile duct invasion and/or tumor occupancy of ≥ 50% of liver. Results: In the ITT population, 64 (19%) pts randomized to atezo + bev and 37 (22%) pts randomized to sor were defined as high risk. 10 pts had bile duct invasion, 73 had Vp4 portal vein invasion and 31 had liver tumor occupancy of ≥ 50%. 9 pts in the atezo + bev arm and 4 pts in the sor arm had 2 high-risk factors. OS, PFS and ORR all favored atezo + bev over sor, in both non-high-risk and high-risk patients. See table for efficacy results. In safety-evaluable pts, Grade 3/4 treatment-related AEs (TRAEs) occurred in 122 (45%) of 269 non-high-risk and 21 (35%) of 60 high-risk atezo + bev pts. Grade 5 TRAEs occurred in 5 (2%) non-high-risk and 1 (2%) high-risk atezo + bev pt. Conclusions: Efficacy benefit was seen with atezo + bev vs sor regardless of the presence of high-risk features. HRs remained similar despite the numerical differences in median OS between non-high-risk and high-risk pts. Further, the overall safety data in the atezo + bev arm were comparable between non-high-risk and high-risk pts and in line with the known safety profile of each drug.

Non-High RiskHigh RiskITTAtezo + BevSorAtezo + BevSorAtezo + BevSorEvaluable for OS/PFS, n2721286437336165Median OS (95% CI), mo22.8 (19.1, 24.9)15.7 (13.2, 19.0)7.6 (6.6, 12.8)5.5 (4.1, 6.7)19.2 (17.0, 23.7)13.4 (11.4, 16.9)HR (95% CI)0.68 (0.51, 0.91)0.62 (0.39, 1.00)0.66 (0.52, 0.85)Median PFS (95% CI), moa7.2 (6.5, 9.6)4.4 (4.0, 5.8)5.4 (4.0, 6.9)2.8 (2.5, 5.3)6.9 (5.7, 8.6)4.3 (4.0, 5.6)HR (95% CI)0.61 (0.48, 0.78)0.74 (0.47, 1.17)0.65 (0.53, 0.81)Evaluable for ORR, n2631246335326159Confirmed ORR, n (%)a,b81 (31)13 (10)16 (25)5 (14)97 (30)18 (11)Complete response, n (%)a20 (8)05 (8)1 (3)25 (8)1 (1)Median DOR (95% CI), moa,c19.0 (14.6, NE)12.6 (4.9, 17.0)16.3 (13.5, NE)16.5 (3.9, NE)18.1 (14.6, NE)14.9 (4.9, 17.0)NCT03434379.Clinical cutoff date: Aug 31, 2020.DOR, duration of response; HR, hazard ratio; IRF, independent review facility; NE, not estimable; ORR, objective response rate; OS, overall survival; PFS, progression-free survival.aAssessed by an IRF per RECIST 1.1.bORR IRF RECIST 1.1-evaluable population was based on patients who presented with measurable disease at baseline.cDOR analysis was based on all confirmed responders.

Citation Format: Richard S. Finn, Shukui Qin, Masafumi Ikeda, Peter R. Galle, Michel Ducreux, Tae-You Kim, Masatoshi Kudo, Ho Yeong Lim, Valeriy Breder, Philippe Merle, Ahmed Kaseb, Daneng Li, Yin-Hsun Feng, Wendy Verret, Alan Nicholas, Lindong Li, Ning Ma, Andrew X. Zhu, Ann-Lii Cheng. IMbrave150: Updated efficacy and safety by risk status in patients (pts) receiving atezolizumab (atezo) + bevacizumab (bev) vs sorafenib (sor) as first-line treatment for unresectable hepatocellular carcinoma (HCC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT009.

Characterization of response to atezolizumab + bevacizumab versus sorafenib for hepatocellular carcinoma: Results from the IMbrave150 trial

BACKGROUND

IMbrave150 is a phase III trial that assessed atezolizumab + bevacizumab (ATEZO/BEV) versus sorafenib (SOR) in patients with unresectable hepatocellular carcinoma (HCC) and demonstrated a significant improvement in clinical outcomes. Exploratory analyses characterized objective response rate (ORR), depth (DpR), and duration of response (DoR), and patients with a complete response (CR).

METHODS

Patients were randomized 2:1 to intravenous ATEZO (1200 mg) + BEV (15 mg/kg) every 3 weeks or oral SOR (400 mg) twice daily. Tumors were evaluated using Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) and HCC-modified RECIST (mRECIST). ORR by prior treatment and largest baseline liver lesion size, DoR, time to response (TTR), and complete response (TTCR) were analyzed.

RESULTS

For both criteria, responses favored ATEZO/BEV versus SOR regardless of prior treatment and in patients with lesions ≥3 cm. Median TTR was 2.8 months per RECIST 1.1 (range: 1.2-12.3 months) and 2.8 months per mRECIST (range: 1.1-12.3 months) with ATEZO/BEV. Patients receiving ATEZO/BEV had a greater DpR, per both criteria, across baseline liver lesion sizes. Characteristics of complete responders were similar to those of the intent-to-treat population. In complete responders receiving ATEZO/BEV per mRECIST versus RECIST 1.1, respectively, median TTCR was shorter (5.5 vs. 7.0 months), mean baseline sum of lesion diameter was longer (5.0 [SD, 5.1] vs. 2.6 [SD, 1.4] cm), and mean largest liver lesion size was larger (4.8 [SD, 4.2] vs. 2.3 [SD, 1.0] cm).

CONCLUSIONS

These data highlight the improved ORR, DpR, and CR rates with ATEZO/BEV in unresectable HCC.

Patient-reported outcomes with atezolizumab plus bevacizumab versus sorafenib in patients with unresectable hepatocellular carcinoma (IMbrave150): an open-label, randomised, phase 3 trial

BACKGROUND

Understanding patients' experience of cancer treatment is important. We aimed to evaluate patient-reported outcomes (PROs) with atezolizumab plus bevacizumab versus sorafenib in patients with advanced hepatocellular carcinoma in the IMbrave150 trial, which has already shown significant overall survival and progression-free survival benefits with this combination therapy.

METHODS

We did an open-label, randomised, phase 3 trial in 111 hospitals and cancer centres across 17 countries or regions. We included patients aged 18 years or older with systemic, treatment-naive, histologically, cytologically, or clinically confirmed unresectable hepatocellular carcinoma and an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, with disease that was not amenable to curative surgical or locoregional therapies, or progressive disease after surgical or locoregional therapies. Participants were randomly assigned (2:1; using permuted block randomisation [blocks of six], stratified by geographical region; macrovascular invasion, extrahepatic spread, or both; baseline alpha-fetoprotein concentration; and ECOG performance status) to receive 1200 mg atezolizumab plus 15 mg/kg bevacizumab intravenously once every 3 weeks or 400 mg sorafenib orally twice a day, until loss of clinical benefit or unacceptable toxicity. The independent review facility for tumour assessment was masked to the treatment allocation. Previously reported coprimary endpoints were overall survival and independently assessed progression-free survival per Response Evaluation Criteria in Solid Tumors 1.1. Prespecified secondary and exploratory analyses descriptively evaluated treatment effects on patient-reported quality of life, functioning, and disease symptoms per the European Organisation for Research and Treatment of Cancer (EORTC) quality-of-life questionnaire for cancer (QLQ-C30) and quality-of-life questionnaire for hepatocellular carcinoma (QLQ-HCC18). Time to confirmed deterioration of PROs was analysed in the intention-to-treat population; all other analyses were done in the PRO-evaluable population (patients who had a baseline PRO assessment and at least one assessment after baseline). The trial is ongoing; enrolment is closed. This trial is registered with ClinicalTrials.gov, NCT03434379.

FINDINGS

Between March 15, 2018, and Jan 30, 2019, 725 patients were screened and 501 patients were enrolled and randomly assigned to atezolizumab plus bevacizumab (n=336) or sorafenib (n=165). 309 patients in the atezolizumab plus bevacizumab group and 145 patients in the sorafenib group were included in the PRO-evaluable population. At data cutoff (Aug 29, 2019) the median follow-up was 8·6 months (IQR 6·2-10·8). EORTC QLQ-C30 completion rates were 90% or greater for 23 of 24 treatment cycles in both groups (range 88-100% in the atezolizumab plus bevacizumab group and 80-100% in the sorafenib group). EORTC QLQ-HCC18 completion rates were 90% or greater for 20 of 24 cycles in the atezolizumab plus bevacizumab group (range 88-100%) and 21 of 24 cycles in the sorafenib group (range 89-100%). Compared with sorafenib, atezolizumab plus bevacizumab reduced the risk of deterioration on all EORTC QLQ-C30 generic cancer symptom scales that were prespecified for analysis (appetite loss [hazard ratio (HR) 0·57, 95% CI 0·40-0·81], diarrhoea [0·23, 0·16-0·34], fatigue [0·61, 0·46-0·81], pain [0·46, 0·34-0·62]), and two of three EORTC QLQ-HCC18 disease-specific symptom scales that were prespecified for analysis (fatigue [0·60, 0·45-0·80] and pain [0·65, 0·46-0·92], but not jaundice [0·76, 0·55-1·07]). At day 1 of treatment cycle five (after which attrition in the sorafenib group was more than 50%), the mean EORTC QLQ-C30 score changes from baseline in the atezolizumab plus bevacizumab versus sorafenib groups were: -3·29 (SD 17·56) versus -5·83 (20·63) for quality of life, -4·02 (19·42) versus -9·76 (21·33) for role functioning, and -3·77 (12·82) versus -7·60 (15·54) for physical functioning.

INTERPRETATION

Prespecified analyses of PRO data showed clinically meaningful benefits in terms of patient-reported quality of life, functioning, and disease symptoms with atezolizumab plus bevacizumab compared with sorafenib, strengthening the combination therapy's positive benefit-risk profile versus that of sorafenib in patients with unresectable hepatocellular carcinoma.

FUNDING

F Hoffmann-La Roche and Genentech.

IMbrave150: Exploratory analysis to examine the association between treatment response and overall survival (OS) in patients (pts) with unresectable hepatocellular carcinoma (HCC) treated with atezolizumab (atezo) + bevacizumab (bev) versus sorafenib (sor)

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Background: Based on IMbrave150 (NCT03434379) results, atezo + bev has been approved in > 60 countries for pts with unresectable HCC who have not received prior systemic therapy (Finn RS, NEJM 2020). OS and objective response rate (ORR) improvements with atezo + bev vs sor were maintained with an additional 12 mo of follow up since primary analysis. Updated median OS was 19.2 mo with atezo + bev vs 13.4 mo with sor (stratified HR, 0.66; 95% CI: 0.52, 0.85). Updated ORR was 30% with atezo + bev vs 11% with sor by independently-assessed (IRF) RECIST 1.1 (Finn RS, ASCO GI 2021). Here, we report an exploratory analysis examining the association of response by RECIST 1.1 with OS and independent predictors of survival. Methods: Pts in this Ph III study were systemic treatment–naive with unresectable HCC, ≥1 measurable untreated lesion (RECIST 1.1), Child-Pugh class A liver function and ECOG PS 0/1. Pts were randomized 2:1 to atezo 1200 mg IV q3w + bev 15 mg/kg IV q3w or sor 400 mg bid until unacceptable toxicity or loss of clinical benefit per investigator. ORR was determined by IRF RECIST 1.1. Kaplan-Meier analyses of OS by response status were conducted without landmark and with 4- and 6-mo landmarks. Multivariate analysis was conducted using Cox modeling with time-dependent covariate (responder [yes/no]) with backwards elimination. These analyses only included pts treated with atezo + bev. Results: IMbrave150 enrolled 501 pts, including 336 treated with atezo + bev. Median follow-up was 15.6 mo. OS was longer in pts with confirmed response per RECIST 1.1 (responders, CR + PR) vs non-responders by Kaplan-Meier analyses without landmark and with 4- and 6-mo landmarks (Table). By multivariate analysis, in addition to responder (yes/no), 5 of the 10 initially included predictors of OS remained in the final Cox model ( P< 0.10): ECOG PS (0/1), geographic region (Asia excluding Japan/rest of the world), etiology (hepatitis B/hepatitis C/non-viral), macrovascular invasion and/or extrahepatic spread (yes/no), and baseline alpha-fetoprotein ( < 400 ng/mL/≥400 ng/mL). Conclusions: Atezo + bev is the new standard of care for pts with previously untreated, unresectable HCC. Here we showed that in IMbrave150 pts treated with atezo + bev, response by RECIST 1.1 was associated with OS, suggesting that confirmed response is an independent predictor of OS in these pts. Clinical trial information: NCT03434379. [Table: see text]

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)

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Background: Atezo + bev has been approved globally for pts with unresectable HCC who have not received prior systemic therapy, based on results from IMbrave150 (NCT03434379). At a median of 8.6 mo follow-up, both coprimary endpoints were met, with statistically significant and clinically meaningful improvements observed with atezo + bev vs sor for OS (HR, 0.58 [95% CI, 0.42, 0.79]; P<0.001) and independently-assessed progression-free survival (PFS; per RECIST 1.1; HR, 0.59 [95% CI, 0.47, 0.76]; P<0.001) (Finn, et al. N Engl J Med 2020). Here, we report an updated OS analysis for IMbrave150. Methods: The global, multicenter, randomized, open-label, Phase III study IMbrave150 enrolled 501 systemic treatment–naive pts with unresectable HCC, ≥1 measurable untreated lesion (RECIST 1.1), Child-Pugh class A liver function and ECOG PS 0/1. Pts were randomized 2:1 to receive either atezo 1200 mg IV q3w + bev 15 mg/kg IV q3w or sor 400 mg bid until unacceptable toxicity or loss of clinical benefit per investigator. This post hoc, descriptive OS analysis was conducted with 12 mo of additional follow up from the primary analysis. Results: 501 pts were enrolled, including 336 to atezo + bev and 165 to sor. At the clinical cut-off date of Aug 31, 2020, median follow-up was 15.6 mo and 280 OS events were observed. Median OS was 19.2 mo with atezo + bev vs 13.4 mo with sor (HR, 0.66 [95% CI, 0.52, 0.85]; P=0.0009). Survival at 18 mo was 52% with atezo + bev and 40% with sor. Survival benefit with atezo + bev over sor was generally consistent across subgroups and with the primary analysis. The updated objective response rate (ORR; 29.8% per RECIST 1.1) with atezo + bev was in line with the primary analysis, with more pts achieving complete response (CR; 7.7%) than previously reported. Additional response data are in Table. Safety was aligned with the primary analysis, with no new signals identified. Conclusions: IMbrave150 showed consistent clinically meaningful treatment benefit and safety with 12 mo of additional follow-up. The combination provides the longest survival seen in a front-line Phase III study in advanced HCC, confirming atezo + bev as a standard of care for previously untreated, unresectable HCC. Clinical trial information: NCT03434379. [Table: see text]

Abstract CT044: Genomic correlates of clinical benefits from atezolizumab combined with bevacizumab vs. atezolizumab alone in patients with advanced hepatocellular carcinoma (HCC)

Background: Atezolizumab (atezo) and bevacizumab (bev) combination therapy has demonstrated robust clinical activity in patients with unresectable HCC who have not received prior systemic therapy (Lee et al., APPLE 2019; Cheng et al., ESMO Asia 2019). In this exploratory analysis, we aimed to identify tumor-based molecular biomarkers that may be associated with clinical response or resistance to atezo + bev. We also investigated how VEGF blockade with bev could potentiate PD-L1 checkpoint inhibition with atezo in pts with advanced HCC. Methods: Archival tumor tissues or fresh biopsies taken prior to treatment were collected from HCC pts enrolled in the Phase 1b trial GO30140 (NCT02715531). Arm A (n = 104) was a single-arm evaluation of atezo + bev; Arm F (n = 119) was a randomized arm comparing atezo + bev with atezo. Whole-exome sequencing was carried out on these tumor tissues to determine tumor mutation burden (TMB). Gene expression in tumors was profiled by RNAseq analysis. The association between biomarker expression and clinical response (responders [R] vs. non-responders [NR]) or PFS was assessed by t-tests or Cox regression models, respectively. All p-values are descriptive. Results: In Arm A, 90/104 pts were biomarker evaluable. TMB was not associated with response to atezo + bev or PFS. In contrast, analysis of baseline tumor gene expression showed that pre-existing immunity appeared to be associated with clinical response and longer PFS, which included high expression of CD274 (PD-L1) (R vs. NR, p &lt; 2.1 × 10−5; PFS: HR = 0.42 [0.25-0.72]), and T effector signature (GZMB, PRF1, CXCL9) (R vs. NR, p &lt; 0.0004; PFS: HR = 0.46 [0.27-0.78]). Gene expression related to Notch pathway activation (i.e. high expression of HES1) appeared to be associated with lack of response to atezo + bev (p &lt; 0.039) and shorter PFS (HR = 2.1 [1.3-3.6]). In Arm F, 91/119 pts were biomarker evaluable. High expression of VEGF receptor 2 (VEGFR2; HR = 0.36 [0.16-0.81]), Treg (HR = 0.35 [0.15-0.82]), myeloid inflammation (HR = 0.43 [0.19-0.95]), and TREM1/MDSC signatures (HR = 0.43 [0.19-0.94]) was associated with longer PFS in patients treated with atezo + bev than in those treated with atezo alone. Analysis of 12 serial biopsy pairs confirmed reduced levels of VEGFR2 and Treg signatures after atezo + bev treatment. Conclusion: We identified candidate biomarkers for predicting response to atezo + bev in HCC. Furthermore, the findings in Arm F are consistent with previous preclinical studies supporting a multi-faceted role of VEGF/VEGFR signaling in promoting immune suppression in addition to angiogenesis. Overall, the data presented here further support the mechanistic hypotheses on how anti-VEGF may combine with immune checkpoint blockade to increase its clinical benefit. As these results are exploratory, future study is needed to confirm these findings in a larger population.

Citation Format: Andrew X. Zhu, Yinghui Guan, Alexander R. Abbas, Hartmut Koeppen, Shan Lu, Chih-Hung Hsu, Kyung-Hun Lee, Michael S. Lee, Aiwu Ruth He, Amit Mahipal, Beiying Ding, Jessica Spahn, Wendy Verret, Baek-Yeol Ryoo, Yulei Wang. Genomic correlates of clinical benefits from atezolizumab combined with bevacizumab vs. atezolizumab alone in patients with advanced hepatocellular carcinoma (HCC) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT044.

Longitudinal and personalized detection of circulating tumor DNA (ctDNA) for monitoring efficacy of atezolizumab plus bevacizumab in patients with unresectable hepatocellular carcinoma (HCC)

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Background: ctDNA has emerged as a promising biomarker for noninvasive monitoring of treatment response and disease progression in many tumor types. However, the clinical use of ctDNA in patients with HCC has not been established. Here, we evaluated longitudinal and personalized detection of ctDNA for monitoring the treatment response to atezolizumab (atezo) + bevacizumab (bev) in patients with unresectable HCC not previously treated with systemic therapy. Methods: A subset (n = 48) of 104 patients with HCC who enrolled in Arm A of GO30140 (NCT02715531; Phase 1b) and received atezo + bev treatment were included in this study. These patients had 10 CR, 11 PR, 12 SD and 15 PD per IRF-assessed RECIST 1.1. Serial plasma samples were collected at baseline (Cycle [C]1 Day [D]1), during treatment (C2D1, C4D1) and at disease progression. Somatic mutations in individual tumors were identified via whole exome sequencing of archival tumor tissues or fresh biopsies collected before treatment. Personalized ctDNA assays (Signatera 16-plex multiplex PCR next-generation sequencing assay) specific to each patient’s tumor mutational signatures were successfully designed for 47 of 48 patients. Results: At C1D1, a median of 25.7 ng of cell-free DNA was extracted from 2-mL plasma samples. ctDNA was detected in 45 of 47 patients (96%), with a median of 70.6 mean tumor molecules/mL of plasma (MTM/mL) and a median of 1.8% mean variant allele frequency (mean VAF) in plasma. Higher ctDNA levels detected at C1D1 appeared to be associated with increased tumor burden ( P < 0.03). Dynamic changes in ctDNA levels post-treatment were associated with response at C4D1. ctDNA status changed from positive at baseline to negative in 7 of 10 CR (70%), 3 of 11 PR (27%), 1 of 11 SD (9%) and 0 of 11 PD (0%) patients. Longer PFS was observed in patients whose ctDNA became undetectable post-treatment. The median PFS in patients with ctDNA present vs cleared at C4D1 was 6.5 months and not reached, respectively (HR, 12 [1.7-93], log-rank P < 0.00029). Conclusions: Our study showed that Signatera, a personalized and tumor-informed ctDNA assay, could be used as a sensitive method for detecting ctDNA in patients with unresectable HCC. More importantly, our results illustrate the promise of ctDNA as an emerging biomarker that may potentially help to monitor treatment responses and disease progression in patients with HCC.

Complete responses (CR) in patients receiving atezolizumab (atezo) + bevacizumab (bev) versus sorafenib (sor) in IMbrave150: A phase III clinical trial for unresectable hepatocellular carcinoma (HCC)

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Background: In the Phase III IMbrave150 trial, statistically significant and clinically meaningful improvements in OS and PFS were seen with atezo + bev vs sor in pts with unresectable HCC who had not received prior systemic therapy (Cheng, ESMO Asia, 2019). Historically, CR rates have been low in HCC clinical trials. Here we report the baseline characteristics for IMbrave150 pts with a CR. Methods: IMbrave150 enrolled systemic treatment-naive pts with unresectable HCC. Pts were randomized 2:1 to receive either atezo 1200 mg IV q3w + bev 15 mg/kg IV q3w or sor 400 mg BID until unacceptable toxicity or loss of clinical benefit per investigator. Co-primary endpoints were OS and PFS by independent review facility (IRF)–assessed RECIST 1.1. The key secondary endpoints IRF ORR per RECIST 1.1 and IRF ORR per HCC mRECIST were also part of the study statistical testing hierarchy. Results: The ITT population included 336 pts randomized to atezo + bev and 165 pts randomized to sor. With a median follow-up of 8.6 mo (data cutoff, Aug 29, 2019), OS HR was 0.58 (95% CI: 0.42, 0.79; P = 0.0006) and PFS HR was 0.59 (95% CI: 0.47, 0.76; P < 0.0001) with atezo + bev vs sor. ORR was 27% vs 12% ( P < 0.0001) per IRF RECIST 1.1 and 33% vs 13% ( P < 0.0001) per IRF HCC mRECIST with atezo + bev vs sor, respectively. For responders (per IRF RECIST 1.1), median time to response was 2.8 mo (range, 1.2-11.3) with atezo + bev and 3.3 mo (range, 1.2-7.2) with sor. CR per IRF-assessed RECIST 1.1 was achieved by 18 pts in the atezo + bev arm and 0 pts in the sor arm. The baseline characteristics for atezo + bev CR pts are shown in the table. Additional characteristics will be shown. Conclusions: IMbrave150 demonstrated statistically significant and clinically meaningful improvement in both OS and PFS with atezo + bev vs sor in pts with unresectable HCC who have not received prior systemic therapy. Pts achieved CRs regardless of poor prognostic factors or etiology. Atezo + bev may be a practice-changing treatment for pts with unresectable HCC. Clinical trial information: NCT03434379 . [Table: see text]

Atezolizumab plus Bevacizumab in Unresectable Hepatocellular Carcinoma

BACKGROUND

The combination of atezolizumab and bevacizumab showed encouraging antitumor activity and safety in a phase 1b trial involving patients with unresectable hepatocellular carcinoma.

METHODS

In a global, open-label, phase 3 trial, patients with unresectable hepatocellular carcinoma who had not previously received systemic treatment were randomly assigned in a 2:1 ratio to receive either atezolizumab plus bevacizumab or sorafenib until unacceptable toxic effects occurred or there was a loss of clinical benefit. The coprimary end points were overall survival and progression-free survival in the intention-to-treat population, as assessed at an independent review facility according to Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1).

RESULTS

The intention-to-treat population included 336 patients in the atezolizumab-bevacizumab group and 165 patients in the sorafenib group. At the time of the primary analysis (August 29, 2019), the hazard ratio for death with atezolizumab-bevacizumab as compared with sorafenib was 0.58 (95% confidence interval [CI], 0.42 to 0.79; P<0.001). Overall survival at 12 months was 67.2% (95% CI, 61.3 to 73.1) with atezolizumab-bevacizumab and 54.6% (95% CI, 45.2 to 64.0) with sorafenib. Median progression-free survival was 6.8 months (95% CI, 5.7 to 8.3) and 4.3 months (95% CI, 4.0 to 5.6) in the respective groups (hazard ratio for disease progression or death, 0.59; 95% CI, 0.47 to 0.76; P<0.001). Grade 3 or 4 adverse events occurred in 56.5% of 329 patients who received at least one dose of atezolizumab-bevacizumab and in 55.1% of 156 patients who received at least one dose of sorafenib. Grade 3 or 4 hypertension occurred in 15.2% of patients in the atezolizumab-bevacizumab group; however, other high-grade toxic effects were infrequent.

CONCLUSIONS

In patients with unresectable hepatocellular carcinoma, atezolizumab combined with bevacizumab resulted in better overall and progression-free survival outcomes than sorafenib. (Funded by F. Hoffmann-La Roche/Genentech; ClinicalTrials.gov number, NCT03434379.).

Patient-reported outcomes (PROs) from the Phase III IMbrave150 trial of atezolizumab (atezo) + bevacizumab (bev) vs sorafenib (sor) as first-line treatment (tx) for patients (pts) with unresectable hepatocellular carcinoma (HCC)

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Background: Atezo + bev in pts with unresectable HCC who had not received prior systemic therapy has shown statistically significant and clinically meaningful improvement in OS and PFS per independent review facility-assessed RECIST 1.1 vs sor in the Phase III IMbrave150 study (Cheng ESMO Asia 2019). Here, we report PRO data from this trial to show pt perspectives on the overall clinical benefit of atezo + bev. Methods: Pts were randomized 2:1 to receive either atezo 1200 mg IV q3w + bev 15 mg/kg IV q3w or sor 400 mg PO BID until loss of clinical benefit or unacceptable toxicity. Pts completed the EORTC QLQ-C30 and EORTC QLQ-HCC18 questionnaires before tx, every 3 wk on tx, and every 3 mo after tx discontinuation or disease progression. A pre-specified secondary endpoint was time to deterioration (TTD; first ≥ 10-point decrease from baseline held for 2 consecutive assessments or 1 assessment followed by death within 3 wk) of pt-reported quality of life (QOL), physical functioning, and role functioning. Pre-specified exploratory analyses included TTD of and proportion of pts with a clinically meaningful change (≥ 10 points from baseline) in key pt-reported symptoms. Results: Questionnaire completion rates were ≥ 92% in both arms from baseline through most of the tx period. Compared with sor, atezo + bev delayed TTD of pt-reported QOL (median TTD, 11.2 vs 3.6 mo; HR, 0.63 [95% CI: 0.46, 0.85]), physical functioning (median TTD, 13.1 vs 4.9 mo; HR, 0.53 [95% CI: 0.39, 0.73]), and role functioning (median TTD, 9.1 vs 3.6 mo; HR, 0.62 [95% CI: 0.46, 0.84]). Atezo + bev also delayed TTD in pt-reported appetite loss, fatigue, pain, and diarrhea vs sor; a lower proportion of pts on atezo + bev experienced clinically meaningful deterioration in each of these symptoms vs sor. Conclusions: High-quality PRO results from IMbrave150 showed large and consistent benefits in key aspects of the pt experience with atezo + bev, further supporting its overall clinical benefit in pts with unresectable HCC who have not received prior systemic therapy. Clinical trial information: NCT03434379.

Final results of a phase 2 study of talazoparib (TALA) following platinum or multiple cytotoxic regimens in advanced breast cancer patients (pts) with germline BRCA1/2 mutations (ABRAZO)

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Background: TALA is a dual-mechanism PARP inhibitor that traps PARP on DNA. This study was designed to assess the activity of TALA in pts with g BRCA1/2mutation previously exposed to platinum or multiple prior cytotoxic regimens. Methods: ABRAZO (NCT02034916) is a 2-cohort, 2-stage phase 2 study of TALA (1 mg/d) following platinum-based therapy (Cohort 1 [C1]) or ≥ 3 platinum-free cytotoxic-based regimens (Cohort 2 [C2]) in pts with locally advanced or metastatic breast cancer (MBC) and g BRCA1/2mutation. Pts had ECOG PS ≤ 1 and measurable disease by RECIST v1.1. Five responses per cohort were required in ≤ 35 pts to progress to stage 2. The primary endpoint was confirmed ORR by independent radiology facility (IRF). Secondary endpoints: clinical benefit rate ≥ 24 weeks (CBR24), DOR, PFS, and OS. Results: From May 2014 to Feb 2016, 84 pts were enrolled (C1, n = 49; C2, n = 35). At data cutoff (1 Sep 2016), 9 pts continued on treatment. Both cohorts proceeded to stage 2 before enrollment closed. Median age was 50 (range, 31–75) years; 58% of pts had an ECOG PS of 0. TNBC/HR+ incidence in C1 and C2 was 59%/41% and 17%/83%, respectively. Median number of prior cytotoxic regimens administered for advanced disease was 2 in C1 and 4 in C2. ORR by IRF for BRCA1/BRCA2 was 24%/34%, and ORR by IRF for TNBC/HR+ was 26%/29%. Common all grade AEs: anemia (52%), fatigue (45%), nausea (42%), diarrhea (33%), thrombocytopenia (33%), and neutropenia (27%). Grade ≥ 3 AEs: anemia (35%), thrombocytopenia (19%), and neutropenia (15%). Nonhematological AEs grade ≥ 3 did not occur. AEs related to TALA led to drug discontinuation in 3 pts (4%); 4 AEs resulted in death, none related to TALA. Conclusions: TALA was well tolerated in MBC pts with a g BRCA1/2 mutation, exhibiting promising antitumor activity in C1 and C2. TALA vs physician’s choice of treatment in g BRCA1/2-mutated MBC is being evaluated in the phase 3 EMBRACA trial (NCT01945775). Clinical trial information: NCT02034916. [Table: see text]

Randomized, Double-Blind, Placebo-Controlled, Multicenter Phase II Study of Onartuzumab Plus Bevacizumab Versus Placebo Plus Bevacizumab in Patients With Recurrent Glioblastoma: Efficacy, Safety, and Hepatocyte Growth Factor and O6-Methylguanine–DNA Methyltransferase Biomarker Analyses

Purpose

Bevacizumab regimens are approved for the treatment of recurrent glioblastoma in many countries. Aberrant mesenchymal-epithelial transition factor (MET) expression has been reported in glioblastoma and may contribute to bevacizumab resistance. The phase II study GO27819 investigated the monovalent MET inhibitor onartuzumab plus bevacizumab (Ona + Bev) versus placebo plus bevacizumab (Pla + Bev) in recurrent glioblastoma.

Methods

At first recurrence after chemoradiation, bevacizumab-naïve patients with glioblastoma were randomly assigned 1:1 to receive Ona (15 mg/kg, once every 3 weeks) + Bev (15 mg/kg, once every 3 weeks) or Pla + Bev until disease progression. The primary end point was progression-free survival by response assessment in neuro-oncology criteria. Secondary end points were overall survival, objective response rate, duration of response, and safety. Exploratory biomarker analyses correlated efficacy with expression levels of MET ligand hepatocyte growth factor, O6-methylguanine–DNA methyltransferase promoter methylation, and glioblastoma subtype.

Results

Among 129 patients enrolled (Ona + Bev, n = 64; Pla + Bev, n = 65), baseline characteristics were balanced. The median progression-free survival was 3.9 months for Ona + Bev versus 2.9 months for Pla + Bev (hazard ratio, 1.06; 95% CI, 0.72 to 1.56; P = .7444). The median overall survival was 8.8 months for Ona + Bev and 12.6 months for Pla + Bev (hazard ratio, 1.45; 95% CI, 0.88 to 2.37; P = .1389). Grade ≥ 3 adverse events were reported in 38.5% of patients who received Ona + Bev and 35.9% of patients who received Pla + Bev. Exploratory biomarker analyses suggested that patients with high expression of hepatocyte growth factor or unmethylated O6-methylguanine–DNA methyltransferase may benefit from Ona + Bev.

Conclusion

There was no evidence of further clinical benefit with the addition of onartuzumab to bevacizumab compared with bevacizumab plus placebo in unselected patients with recurrent glioblastoma in this phase II study; however, further investigation into biomarker subgroups is warranted.

Lung deposition and pharmacokinetics of nebulized cyclosporine in lung transplant patients

BACKGROUND

Inhaled cyclosporine (CsA) is being investigated as a prophylaxis for lung transplant rejection. Lung deposition and systemic exposure of nebulized CsA in lung transplant patients was evaluated as part of the Phase 3 cyclosporine inhalation solution (CIS) trial (CYCLIST).

METHODS

Ten patients received 300 mg of CIS (62.5 mg/mL CsA in propylene glycol) admixed with 148 MBq of Tc-DTPA (technetium-99m bound to diethylenetriaminepentaacetic acid) administered using a Sidestream(®) disposable jet nebulizer. Deposition was assessed using a dual-headed gamma camera. Blood samples were collected over a 24-hr time period after aerosol dosing and analyzed for CsA levels. A pharmacokinetic analysis of the resulting blood concentration versus time profiles was performed.

RESULTS

The average total deposited dose was 53.7 ± 12.7 mg. Average pulmonary dose was 31.8 ± 16.3 mg, and stomach dose averaged 15.5 ± 11.1 mg. Device performance was consistent, with breathing maneuvers influencing dose variation. Predose coaching with five of 10 patients reduced stomach deposition (22.6 ± 11.2 vs. 8.3 ± 5.2 mg; p=0.03). Blood concentrations declined quickly from a maximum of 372 ± 140 ng/mL to 15.3 ± 9.7 ng/mL at 24 hr post dose. Levels of AUC(0-24) [area under the concentration vs. time curve from 0 to 24 hr] averaged 1,493 ± 746 ng hr/mL. On a three times per week dose regimen, this represents <5% of the weekly systemic exposure of twice per day oral administration.

CONCLUSIONS

Substantial doses of CsA can be delivered to the lungs of lung transplant patients by inhaled aerosol. Systemic levels are small relative to typical oral CsA administration.

The association between malnutrition and the incidence of malaria among young HIV-infected and -uninfected Ugandan children: a prospective study

BACKGROUND

In sub-Saharan Africa, malnutrition and malaria remain major causes of morbidity and mortality in young children. There are conflicting data as to whether malnutrition is associated with an increased or decreased risk of malaria. In addition, data are limited on the potential interaction between HIV infection and the association between malnutrition and the risk of malaria.

METHODS

A cohort of 100 HIV-unexposed, 203 HIV-exposed (HIV negative children born to HIV-infected mothers) and 48 HIV-infected children aged 6 weeks to 1 year were recruited from an area of high malaria transmission intensity in rural Uganda and followed until the age of 2.5 years. All children were provided with insecticide-treated bed nets at enrolment and daily trimethoprim-sulphamethoxazole prophylaxis (TS) was prescribed for HIV-exposed breastfeeding and HIV-infected children. Monthly routine assessments, including measurement of height and weight, were conducted at the study clinic. Nutritional outcomes including stunting (low height-for-age) and underweight (low weight-for-age), classified as mild (mean z-scores between -1 and -2 during follow-up) and moderate-severe (mean z-scores < -2 during follow-up) were considered. Malaria was diagnosed when a child presented with fever and a positive blood smear. The incidence of malaria was compared using negative binomial regression controlling for potential confounders with measures of association expressed as an incidence rate ratio (IRR).

RESULTS

The overall incidence of malaria was 3.64 cases per person year. Mild stunting (IRR = 1.24, 95% CI 1.06-1.46, p = 0.008) and moderate-severe stunting (IRR = 1.24, 95% CI 1.03-1.48, p = 0.02) were associated with a similarly increased incidence of malaria compared to non-stunted children. Being mildly underweight (IRR = 1.09, 95% CI 0.95-1.25, p = 0.24) and moderate-severe underweight (IRR = 1.12, 95% CI 0.86-1.46, p = 0.39) were not associated with a significant difference in the incidence of malaria compared to children who were not underweight. There were no significant interactions between HIV-infected, HIV-exposed children taking TS and the associations between malnutrition and the incidence of malaria.

CONCLUSIONS

Stunting, indicative of chronic malnutrition, was associated with an increased incidence of malaria among a cohort of HIV-infected and -uninfected young children living in an area of high malaria transmission intensity. However, caution should be made when making causal inferences given the observational study design and inability to disentangle the temporal relationship between malnutrition and the incidence of malaria.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00527800.