Final results of RIGHT Choice: Ribociclib plus endocrine therapy vs combination chemotherapy in premenopausal women with clinically aggressive HR+/HER2- advanced breast cancer

PURPOSE

A head-to-head comparison of efficacy between a cyclin-dependent kinase 4/6 inhibitor plus endocrine therapy (ET) versus combination chemotherapy (CT) has never been reported in patients with clinically aggressive hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer (ABC).

PATIENTS AND METHODS

In this open-label, multi-center, randomized phase 2 trial, pre/perimenopausal women with clinically aggressive HR+/HER2- ABC were randomized 1:1 to first-line ribociclib (600 mg daily; 3-weeks-on, 1-week-off) plus letrozole/anastrozole and goserelin or investigator's choice of combination CT (docetaxel plus capecitabine, paclitaxel plus gemcitabine, or capecitabine plus vinorelbine). The primary endpoint was progression-free survival (PFS).

RESULTS

Among 222 patients randomized to ribociclib plus ET (n=112) or combination CT (n=110), 150 (67.6%) had symptomatic visceral metastases, 41 (18.5%) had rapid disease progression per investigator's judgment, and 31 (14.0%) had symptomatic non-visceral disease. Overall, 106 (47.7%) patients had investigator-assessed visceral crisis. Median follow-up time was 37.0 months. At data cutoff, 31.3% (ribociclib arm) and 15.5% (CT arm) of patients had completed study treatment and transitioned to post-trial access. The median PFS was 21.8 months (ribociclib plus ET; 95% CI, 17.4-26.7 months) and 12.8 months (combination CT; 95% CI, 10.1-18.4 months); hazard ratio [HR], 0.61; 95% CI, 0.43-0.87; P=.003. The overall response rates and the median time to response in the ribociclib versus CT arms, respectively, were 66.1% and 61.8% and 4.9 months and 3.2 months (HR, 0.76; 95% CI, 0.55-1.06). Lower rates of symptomatic adverse events were observed in the ribociclib versus CT arm.

CONCLUSIONS

First-line ribociclib plus ET showed a significant PFS benefit, similar response rates, and better tolerability over combination CT in patients with clinically aggressive HR+/HER2- ABC.

CREST: phase III study of sasanlimab and Bacillus Calmette-Guérin for patients with Bacillus Calmette-Guérin-naïve high-risk non-muscle-invasive bladder cancer

Bacillus Calmette-Guérin (BCG) is the standard of care for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) after transurethral resection of bladder tumor (TURBT). BCG in combination with programmed cell death-1 (PD-1) inhibitors may yield greater anti-tumor activity compared with either agent alone. CREST is a phase III study evaluating the efficacy and safety of the subcutaneous PD-1 inhibitor sasanlimab in combination with BCG for patients with BCG-naive high-risk NMIBC. Eligible participants are randomized to receive sasanlimab plus BCG (induction ± maintenance) or BCG alone for up to 25 cycles within 12 weeks of TURBT. The primary outcome is event-free survival. Secondary outcomes include additional efficacy end points and safety. The target sample size is around 1000 participants.

Efficacy of Lorlatinib in Treatment-Naive Patients With ALK-Positive Advanced NSCLC in Relation to EML4::ALK Variant Type and ALK With or Without TP53 Mutations

INTRODUCTION

Lorlatinib, a third-generation ALK tyrosine kinase inhibitor, improved outcomes compared with crizotinib in patients with previously untreated ALK-positive advanced NSCLC in the phase 3 CROWN study. Here, we investigated response correlates using plasma circulating tumor DNA (ctDNA) and tumor tissue profiling.

METHODS

ALK fusions and ALK with or without TP53 mutations were assessed by next-generation sequencing. End points included objective response rate (ORR), duration of response, and progression-free survival (PFS) by blinded independent central review on the basis of EML4::ALK variants and ALK with or without TP53 or other mutation status.

RESULTS

ALK fusions were detected in the ctDNA of 62 patients in the lorlatinib arm and 64 patients in the crizotinib arm. ORRs were numerically higher with lorlatinib versus crizotinib for EML4::ALK variant 1 (v1; 80.0% versus 50.0%) and variant 2 (v2; 85.7% versus 50.0%) but were similar between the arms for variant 3 (v3; 72.2% versus 73.9%). Median PFS in the lorlatinib arm was not reached for EML4::ALK v1 and v2 and was 33.3 months for v3; in the crizotinib arm, median PFS was 7.4 months, not reached, and 5.5 months, respectively. ORRs and PFS were improved with lorlatinib versus crizotinib regardless of TP53 mutation status and in patients harboring preexisting bypass pathway resistance alterations. In the lorlatinib arm, PFS was lower in patients who had a co-occurring TP53 mutation. Results from ctDNA analysis were similar to those observed with tumor tissue samples.

CONCLUSIONS

Patients with untreated ALK-positive advanced NSCLC derived greater clinical benefits, with higher ORRs and potentially longer PFS, when treated with lorlatinib compared with crizotinib, independent of EML4::ALK variant or ALK mutations, TP53 mutations, or bypass resistance alterations.

A phase Ib/II dose expansion study of subcutaneous sasanlimab in patients with locally advanced or metastatic non-small-cell lung cancer and urothelial carcinoma

BACKGROUND

Sasanlimab is an antibody to the programmed cell death protein 1 receptor. We report updated data of subcutaneous sasanlimab in non-small-cell lung cancer (NSCLC) and urothelial carcinoma dose expansion cohorts from a first-in-human phase Ib/II study.

PATIENTS AND METHODS

Patients were ≥18 years of age with NSCLC or urothelial carcinoma, and no prior immunotherapies, who progressed on or were intolerant to systemic therapy, or for whom systemic therapy was refused or unavailable. Patients received subcutaneous sasanlimab at 300 mg every 4 weeks (q4w). Primary objectives were to evaluate safety, tolerability, and clinical efficacy by objective response rate (ORR).

RESULTS

Sixty-eight and 38 patients with NSCLC and urothelial carcinoma, respectively, received subcutaneous sasanlimab. Overall, sasanlimab was well tolerated; 13.2% of patients experienced grade ≥3 treatment-related adverse events. Confirmed ORR was 16.4% and 18.4% in the NSCLC and urothelial carcinoma cohorts, respectively. ORR was generally higher in patients with high programmed death-ligand 1 (PD-L1) expression (≥25%) and high tumor mutational burden (TMB; >75%). In the NSCLC and urothelial carcinoma cohorts, median progression-free survival (PFS) was 3.7 and 2.9 months, respectively; corresponding median overall survival (OS) was 14.7 and 10.9 months. Overall, longer median PFS and OS correlated with high PD-L1 expression and high TMB. Longer median PFS and OS were also associated with T-cell inflamed gene signature in the urothelial carcinoma cohort.

CONCLUSIONS

Subcutaneous sasanlimab at 300 mg q4w was well tolerated with promising clinical efficacy observed. Phase II and III clinical trials of sasanlimab are ongoing to validate clinical benefit. Subcutaneous sasanlimab may be a potential treatment option for patients with NSCLC or urothelial carcinoma.

Cemiplimab Plus Chemotherapy Versus Chemotherapy Alone in Advanced NSCLC: 2-Year Follow-Up From the Phase 3 EMPOWER-Lung 3 Part 2 Trial

INTRODUCTION

EMPOWER-Lung 3 part 2 (NCT03409614), a double-blind, placebo-controlled phase 3 study, investigated cemiplimab (antiprogrammed cell death protein 1) plus chemotherapy versus placebo plus chemotherapy in patients with advanced NSCLC without EGFR, ALK, or ROS1 aberrations, with either squamous or nonsquamous histology, irrespective of programmed death-ligand 1 levels. At primary analysis, after 16.4 months of follow-up, cemiplimab plus chemotherapy improved median overall survival (OS) versus chemotherapy alone (21.9 versus 13.0 mo, hazard ratio [HR] = 0.71, 95% confidence interval [CI]: 0.53-0.93, p = 0.014). Here, we report protocol-specified final OS and 2-year follow-up results.

METHODS

Patients (N = 466) were randomized 2:1 to receive histology-specific platinum-doublet chemotherapy, with 350 mg cemiplimab (n = 312) or placebo (n = 154) every 3 weeks for up to 108 weeks. Primary end point was OS; secondary end points included progression-free survival and objective response rates.

RESULTS

After 28.4 months of median follow-up, median OS was 21.1 months (95% CI: 15.9-23.5) for cemiplimab plus chemotherapy versus 12.9 months (95% CI: 10.6-15.7) for chemotherapy alone (HR = 0.65, 95% CI: 0.51-0.82, p = 0.0003); median progression-free survival was 8.2 months (95% CI: 6.4-9.0) versus 5.5 months (95% CI: 4.3-6.2) (HR = 0.55, 95% CI: 0.44-0.68, p < 0.0001), and objective response rates were 43.6% versus 22.1%, respectively. Safety was generally consistent with previously reported data. Incidence of treatment-emergent adverse events of grade 3 or higher was 48.7% with cemiplimab plus chemotherapy and 32.7% with chemotherapy alone.

CONCLUSIONS

At protocol-specified final OS analysis with 28.4 months of follow-up, the EMPOWER-Lung 3 study continued to reveal benefit of cemiplimab plus chemotherapy versus chemotherapy alone in patients with advanced squamous or nonsquamous NSCLC, across programmed death-ligand 1 levels.

Quality of life with cemiplimab plus chemotherapy for first-line treatment of advanced non-small cell lung cancer: Patient-reported outcomes from phase 3 EMPOWER-Lung 3

BACKGROUND

EMPOWER-Lung 3, a randomized 2:1 phase 3 trial, showed clinically meaningful and statistically significant overall survival improvement with cemiplimab plus platinum-doublet chemotherapy versus placebo plus chemotherapy for first-line treatment of advanced non-small cell lung cancer. This study evaluated patient-reported outcomes (PROs).

METHODS

PROs were assessed at day 1 (baseline), the start of each treatment cycle (every 3 weeks) for the first six doses, and then at start of every three cycles, using the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life-Core 30 (QLQ-C30) and Quality of Life-Lung Cancer Module (QLQ-LC13) questionnaires. Prespecified analyses included a longitudinal mixed-effect model comparing treatment arms and a time to definitive clinically meaningful deterioration (TTD) analysis performed for global health status/quality of life (GHS/QoL) and all scales from the questionnaires. Between-arm TTD comparisons were made using a stratified log-rank test and proportional hazards model.

RESULTS

A total of 312 patients were assigned to receive cemiplimab plus platinum-doublet chemotherapy and 154 to receive placebo plus chemotherapy; 391 (83.9%) were male and the median age was 63.0 years (range, 25-84). For pain symptoms (EORTC QLQ-C30), a statistically significant overall improvement from baseline (-4.98, 95% confidence interval [CI] -8.36 to -1.60, p = .004) and a statistically significant delay in TTD (hazard ratio, 0.39; 95% CI, 0.26-0.60, p < .0001) favoring cemiplimab plus chemotherapy were observed. Statistically significant delays in TTD, all favoring cemiplimab plus chemotherapy, were also observed in functioning and symptom scales. A significant overall improvement from baseline in GHS/QoL was seen for cemiplimab plus chemotherapy compared with nonsignificant overall change from baseline for placebo plus chemotherapy (1.69, 95% CI, 0.20-3.19 vs. 1.08, 95% CI, -1.34 to 3.51; between arms, p = .673). No analyses yielded statistically significant PRO results favoring placebo plus chemotherapy for any QLQ-C30 or QLQ-LC13 scale.

CONCLUSION

Cemiplimab plus chemotherapy resulted in significant overall improvement in pain symptoms and delayed TTD in cancer-related and lung cancer-specific symptoms and functions.

Extended follow-up from JAVELIN Renal 101: subgroup analysis of avelumab plus axitinib versus sunitinib by the International Metastatic Renal Cell Carcinoma Database Consortium risk group in patients with advanced renal cell carcinoma

BACKGROUND

We report updated data for avelumab plus axitinib versus sunitinib in patients with advanced renal cell carcinoma from the third interim analysis of the phase III JAVELIN Renal 101 trial.

PATIENTS AND METHODS

Progression-free survival (PFS), objective response rate (ORR), and duration of response per investigator assessment (RECIST version 1.1) and overall survival (OS) were evaluated in the overall population and in International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk groups; safety was also assessed.

RESULTS

Overall, median OS [95% confidence interval (CI)] was not reached [42.2 months-not estimable (NE)] with avelumab plus axitinib versus 37.8 months (31.4-NE) with sunitinib [hazard ratio (HR) 0.79, 95% CI 0.643-0.969; one-sided P = 0.0116], and median PFS (95% CI) was 13.9 months (11.1-16.6 months) versus 8.5 months (8.2-9.7 months), respectively (HR 0.67, 95% CI 0.568-0.785; one-sided P < 0.0001). In patients with IMDC favorable-, intermediate-, poor-, or intermediate plus poor-risk disease, respectively, HRs (95% CI) for OS with avelumab plus axitinib versus sunitinib were 0.66 (0.356-1.223), 0.84 (0.649-1.084), 0.60 (0.399-0.912), and 0.79 (0.636-0.983), and HRs (95% CIs) for PFS were 0.71 (0.490-1.016), 0.71 (0.578-0.866), 0.45 (0.304-0.678), and 0.66 (0.550-0.787), respectively. ORRs, complete response rates, and durations of response favored avelumab plus axitinib overall and across all risk groups. In the avelumab plus axitinib arm, 81.1% had a grade ≥3 treatment-emergent adverse event (TEAE), and incidences of TEAEs and immune-related AEs were highest <6 months after randomization.

CONCLUSIONS

Avelumab plus axitinib continues to show improved efficacy versus sunitinib and a tolerable safety profile overall and across IMDC risk groups. The OS trend favors avelumab plus axitinib versus sunitinib, but data remain immature; follow-up is ongoing.

TRIAL REGISTRATION

ClinicalTrials.govNCT02684006; https://clinicaltrials.gov/ct2/show/NCT02684006.

Abstract PD18-11: Dose-Expansion Study of Trastuzumab Deruxtecan as Monotherapy or Combined With Pertuzumab in Patients With Metastatic Human Epidermal Growth Factor Receptor 2-Positive (HER2+) Breast Cancer in DESTINY-Breast07 (DB-07)

Background: In trials of HER2+ metastatic breast cancer (mBC), trastuzumab deruxtecan (T-DXd) monotherapy showed durable efficacy (DESTINY-Breast01) and significantly prolonged progression-free survival vs trastuzumab emtansine (DESTINY-Breast03). T-DXd is approved in the US for patients with HER2+ unresectable/mBC who received ≥1 prior anti-HER2–based treatment (tx) in the metastatic or neo-/adjuvant setting and recommended for approval in the EU as 2nd-line tx. Preclinical data suggest that T-DXd used in combination with other anticancer tx may lead to improved efficacy. The purpose of DB-07 is to assess the safety and efficacy of T-DXd alone or with other anticancer tx for patients with HER2+ mBC. Here we report preliminary data from the DB-07 dose-expansion phase for T-DXd monotherapy and T-DXd + pertuzumab (P) as 1st-line (1L) tx in mBC.

Methods: DB-07 (NCT04538742) is an ongoing, phase 1b/2, 2-part (part 1: dose finding; part 2: dose expansion), modular, open-label trial of T-DXd alone or with other anticancer tx in patients with HER2+ mBC. In part 2, patients in module (mod) 0 received T-DXd 5.4 mg/kg every 3 weeks (Q3W) and in mod 2, T-DXd 5.4 mg/kg + P 420 mg Q3W (loading dose: 840 mg), the recommended phase 2 dose. Patients in these mods must be mBC tx naive. For part 2, the primary objective is to assess safety and tolerability. A secondary objective is to assess the objective response rate (ORR) per local investigators by Response Evaluation Criteria In Solid Tumors v1.1. We report results for patients randomized before Oct 13, 2021 to mods 0 and 2 of part 2 (data cutoff [DCO]: Mar 4, 2022); recruitment is ongoing. Based on the distinct mechanism of action of T-DXd and P, we conducted preclinical studies with the drugs in HER2-overexpressing cell lines to elucidate their potential synergies. To assess the effects on T-DXd internalization, live cell imaging was performed using pH-dependent fluorescently labeled T-DXd. To assess the effects on HER2 signaling, total and p-HER2 levels and downstream substrates were evaluated by immunoblot.

Results: 23 patients were enrolled in the T-DXd monotherapy mod; 20 (87.0%) were receiving tx and 3 (13.0%) discontinued tx (withdrawal by patient, n=2; adverse event [AE], n=1) by DCO. 22 patients were enrolled in the T-DXd + P mod; 20 (90.9%) were receiving tx and 2 (9.1%) discontinued tx (AE, n=1; disease progression, n=1) by DCO. All patients experienced AEs (Table); 1 patient in each mod died. The unconfirmed ORR (80% CI) with T-DXd monotherapy and T-DXd + P was 82.6% (68.2%-92.2%) and 77.3% (61.9%-88.5%), respectively; updated data will be presented. Preclinical studies showed that T-DXd was more rapidly and effectively internalized in combination with P than when administered alone. Immunoblotting of cell lysates showed a greater reduction in total HER2 and HER2 signaling in response to combination tx than with T-DXd or P alone.

Discussion: In summary, 1L T-DXd monotherapy and T-DXd + P safety profiles and antitumor activity were consistent with those previously reported for T-DXd. Mature data in these mods are awaited, and other T-DXd combinations are being investigated in additional mods. Preclinical studies showed the potential for P to induce greater internalization of T-DXd and inhibition of HER2-driven signaling. These results support investigation of T-DXd in larger ongoing trials (eg, NCT04784715).

Table 1: Summary of treatment duration and safety data

Citation Format: Erika Hamilton, Komal Jhaveri, Sherene Loi, Carey Anders, Peter Schmid, Konstantin Penkov, Elena Artamonova, Lyudmila Zhukova, Daniil L. Stroyakovsky, Dinesh Chandra Doval, Rafael Villanueva, Flavia Michelini, Sarat Chandarlapaty, Matt Wilson, Sarice R. Boston, Adam Konpa, Shoubhik Mondal, Fabrice Andre. Dose-Expansion Study of Trastuzumab Deruxtecan as Monotherapy or Combined With Pertuzumab in Patients With Metastatic Human Epidermal Growth Factor Receptor 2-Positive (HER2+) Breast Cancer in DESTINY-Breast07 (DB-07) [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 PD18-11.

A multi-center, open-label, randomized dose expansion study of PF-06821497, a potent and selective inhibitor of enhancer of zeste homolog 2 (EZH2), in patients with metastatic castration-resistant prostate cancer (mCRPC)

TPS282

Background: Enhancer of zeste homolog 2 (EZH2) encodes the histone methyltransferase component of the polycomb repressive complex-2, inducing transcriptional silencing of target genes, and is altered in cancers such as follicular lymphoma (FL), small cell lung cancer (SCLC), and metastatic castration-resistant prostate cancer (mCRPC). We evaluated the pharmacokinetics (PK), safety, and antitumor activity of PF-06821497, a potent and selective inhibitor of EZH2, in an ongoing phase I trial (NCT03460977 ) in patients (pts) with SCLC, CRPC, and FL as monotherapy and in combination with standard of care therapies. For pts with CRPC, the PF-06821497 recommended dose for expansion (RDE) is 1250 mg BID, in combination with enzalutamide plus androgen deprivation therapy (E). Part 2B of this trial further explores outcomes for pts dosed with PF-06821497 and E compared with E monotherapy. Methods: Part 2B compares the safety and efficacy of twice-daily PF-06821497 in combination with E (160 mg daily) (treatment arm) versus E monotherapy (control arm) administered continuously in patients with mCRPC previously treated with abiraterone. At trial entry, all pts will have evidence of prostate cancer progression per the modified Prostate Cancer Working Group 3 Criteria. Prior treatment with E is not allowed. Approximately 80 participants will be randomized in a 1:1 fashion into two arms, in US, Spain, and other countries. Approximately 40 participants are required in each arm to have 80% power in the study in order to detect a hazard ratio of 0.5 (E plus PF-06821497: E alone). Patients randomized to E alone have the option to add PF-06821497 to their regimen upon confirmed radiographic disease progression. The primary objectives are to confirm the safety and tolerability of PF-06821497 in combination with E in pts with mCRPC, and to assess the effect of PF-06821497 in combination with E versus E monotherapy on radiographic progression free survival. Secondary objectives include further evaluation of anti-tumor activity of PF-06821497, and assessment of single and multiple dose PK when given in combination with E. The impact of PF-06821497 in combination with E and of E alone in men with mCRPC on patient reported outcomes will also be assessed. Clinical trial information: NCT03460977 .

Post Hoc Analysis of Lorlatinib Intracranial Efficacy and Safety in Patients With ALK-Positive Advanced Non-Small-Cell Lung Cancer From the Phase III CROWN Study

PURPOSE

Lorlatinib significantly improved progression-free survival (PFS) versus crizotinib and showed robust intracranial activity in patients with previously untreated advanced ALK-positive non-small-cell lung cancer (NSCLC) in the phase III CROWN trial. Here, we report post hoc efficacy outcomes in patients with and without brain metastases at baseline, and present data on the incidence and management of CNS adverse events (AEs) in CROWN.

METHODS

Eligible patients were randomly assigned 1:1 to first-line lorlatinib (100 mg once daily) or crizotinib (250 mg twice a day); no crossover between treatment arms was permitted. Tumor assessments, including CNS magnetic resonance imaging, were performed at screening and then at 8-week intervals. Regular assessments of patient-reported outcomes were conducted.

RESULTS

PFS by blinded independent central review was improved with lorlatinib versus crizotinib in patients with and without brain metastases at baseline (12-month PFS rates: 78% v 22% and 78% v 45%, respectively). Lorlatinib was associated with lower 12-month cumulative incidence of CNS progression versus crizotinib in patients with (7% v 72%) and without (1% v 18%) brain metastases at baseline. In total, 35% of patients had CNS AEs with lorlatinib, most of grade 1 severity. Occurrence of CNS AEs did not result in a clinically meaningful difference in patient-reported quality of life. At analysis, 56% of CNS AEs had resolved (33% without intervention; 17% with lorlatinib dose modification), and 38% were unresolved; most required no intervention. Lorlatinib dose modification did not notably influence PFS.

CONCLUSION

First-line lorlatinib improved PFS outcomes and reduced CNS progression versus crizotinib in patients with advanced ALK-positive non-small-cell lung cancer with or without brain metastases at baseline. Half of all CNS AEs resolved without intervention or with lorlatinib dose modification.

Phase 3 trial of lorlatinib in treatment-naive patients (Pts) with ALK-positive advanced non–small cell lung cancer (NSCLC): Comprehensive plasma and tumor genomic analyses

9070

Background: Lorlatinib, a third-generation ALK tyrosine kinase inhibitor, has shown overall and intracranial activity in ALK+ advanced NSCLC. In the randomized, multicenter, phase 3 study in pts with previously untreated ALK+ advanced NSCLC (CROWN; NCT03052608), lorlatinib showed a statistically significant and clinically meaningful improvement in progression-free survival (PFS) vs crizotinib (Shaw AT, et al. N Engl J Med. 2020;383:2018-2029). Comprehensive molecular profiling of circulating tumor DNA (ctDNA) and tumor tissue was performed to identify molecular correlates of response. Methods: At baseline (BL), plasma samples were available from 134 and 129 pts in the lorlatinib and crizotinib arms, respectively. Analyses returned results for tumor tissue (archived or new biopsy) from 147 pts across both arms. Plasma and tumor DNA were analyzed by next-generation sequencing (NGS; Guardant360 and TissueNext, respectively, Guardant Health, Inc.). Objective response rate (ORR), duration of response, and PFS based on the September 20, 2021, cutoff, all assessed by blinded independent central review, were summarized according to mutation and tumor mutation burden (TMB) status. Results: At BL, 22% of pts had no detectable ctDNA. ALK missense mutations (n=19) or deletion (n=1) were detected in plasma of 12 pts (n=5 and 7 in the lorlatinib and crizotinib arms, respectively). Most pts harbored 1 mutation, but 3 pts harbored ≥3 mutations. In tumor samples, no somatic ALK mutation was detected. ALK fusions were detected in plasma of 48% of pts and in tumor of 80%. EML4-ALK variant (v) subtypes were highly concordant between ctDNA and tumor tissue. Based on ctDNA, ORRs were generally higher in the lorlatinib vs crizotinib arm, reaching 80% and 72% for EML4-ALK v1 and v3, respectively, in the lorlatinib arm, and 50% and 74% in the crizotinib arm. Median PFS was not reached for v1 in the lorlatinib arm and was 7.4 mo in the crizotinib arm; for v3, mPFS was 33.3 and 5.5 mo, respectively. TP53 mutations were found in 42% of pts with detectable ctDNA, and their presence did not seem to influence lorlatinib activity. In the crizotinib arm, absence of TP53 mutations led to longer PFS. These findings are being verified in tumor tissue. A pt treated with lorlatinib with an ongoing partial response in tumor lesions at the data cutoff date was found to have a KRAS G12V mutation and the presence of ALK fusion in tumor tissue but had no ctDNA detected at BL. Conclusions: Pts with untreated ALK+ advanced NSCLC had higher ORRs and potentially longer PFS across predefined biomarker subgroups when treated with lorlatinib compared with crizotinib in the phase 3 CROWN study. Based on pretreatment ctDNA and tumor tissue analyses, lorlatinib led to strong clinical benefit regardless of the type of ALK rearrangement or presence of potential driver co-mutation. Clinical trial information: NCT03052608.

Cemiplimab plus chemotherapy versus chemotherapy alone in non-small cell lung cancer: a randomized, controlled, double-blind phase 3 trial

First-line cemiplimab (anti-programmed cell death-1 (PD-1)) monotherapy has previously shown significant improvement in overall survival (OS) and progression-free survival (PFS) versus chemotherapy in patients with advanced non-small cell lung cancer (aNSCLC) and PD-ligand 1 (PD-L1) expression ≥50%. EMPOWER-Lung 3 ( NCT03409614 ), a double-blind, placebo-controlled, phase 3 study, examined cemiplimab plus platinum-doublet chemotherapy as first-line treatment for aNSCLC, irrespective of PD-L1 expression or histology. In this study, 466 patients with stage III/IV aNSCLC without EGFR, ALK or ROS1 genomic tumor aberrations were randomized (2:1) to receive cemiplimab 350 mg (n = 312) or placebo (n = 154) every 3 weeks for up to 108 weeks in combination with four cycles of platinum-doublet chemotherapy (followed by pemetrexed maintenance as indicated). In total, 57.1% (266/466 patients) had non-squamous NSCLC, and 85.2% (397/466 patients) had stage IV disease. The primary endpoint was OS. The trial was stopped early per recommendation of the independent data monitoring committee, based on meeting preset OS efficacy criteria: median OS was 21.9 months (95% confidence interval (CI), 15.5-not evaluable) with cemiplimab plus chemotherapy versus 13.0 months (95% CI, 11.9-16.1) with placebo plus chemotherapy (hazard ratio (HR) = 0.71; 95% CI, 0.53-0.93; P = 0.014). Grade ≥3 adverse events occurred with cemiplimab plus chemotherapy (43.6%, 136/312 patients) and placebo plus chemotherapy (31.4%, 48/153 patients). Cemiplimab is only the second anti-PD-1/PD-L1 agent to show efficacy in aNSCLC as both monotherapy and in combination with chemotherapy for both squamous and non-squamous histologies.

Efficacy and Safety of Rovalpituzumab Tesirine Compared With Topotecan as Second-Line Therapy in DLL3-High SCLC: Results From the Phase 3 TAHOE Study

INTRODUCTION

DLL3, an atypical Notch ligand, is expressed in SCLC tumors but is not detectable in normal adult tissues. Rovalpituzumab tesirine (Rova-T) is an antibody-drug conjugate containing a DLL3-targeting antibody tethered to a cytotoxic agent pyrrolobenzodiazepine by means of a protease-cleavable linker. The efficacy and safety of Rova-T compared with topotecan as second-line therapy in patients with SCLC expressing high levels of DLL3 (DLL3-high) was evaluated.

METHODS

The TAHOE study was an open-label, two-to-one randomized, phase 3 study comparing Rova-T with topotecan as second-line therapy in DLL3-high advanced or metastatic SCLC. Rova-T (0.3 mg/kg) was administered intravenously on day 1 of a 42-day cycle for two cycles, with two additional cycles available to patients who met protocol-defined criteria for continued dosing. Topotecan (1.5 mg/m2) was administered intravenously on days 1 to 5 of a 21-day cycle. The primary end point was overall survival (OS).

RESULTS

Patients randomized to Rova-T (n = 296) and topotecan (n = 148) were included in the efficacy analyses. The median age was 64 years, and 77% had the extensive disease at initial diagnosis. The median OS (95% confidence interval) was 6.3 months (5.6-7.3) in the Rova-T arm and 8.6 months (7.7-10.1) in the topotecan arm (hazard ratio, 1.46 [95% confidence interval: 1.17-1.82]). An independent data monitoring committee recommended that enrollment be discontinued because of the shorter OS observed with Rova-T compared with topotecan. Safety profiles for both drugs were consistent with previous reports.

CONCLUSIONS

Compared with topotecan, which is the current standard second-line chemotherapy, Rova-T exhibited an inferior OS and higher rates of serosal effusions, photosensitivity reaction, and peripheral edema in patients with SCLC. A considerable unmet therapeutic need remains in this population.

Abstract LB043: Efficacy of Lorlatinib in Treatment-Naïve Patients (pts) With ALK-Positive Advanced Non-Small Cell Lung Cancer (NSCLC) in Relation to EML4-ALK Variant Type and ALK Mutations

BACKGROUND: Lorlatinib, a 3rd generation ALK tyrosine kinase inhibitor, has shown overall and intracranial activity in ALK+ advanced NSCLC. In the randomized, multicenter, phase 3 study in pts with previously untreated ALK+ advanced NSCLC (CROWN; NCT03052608), lorlatinib resulted in a statistically significant and clinically meaningful improvement in progression-free survival (PFS) vs crizotinib.1 To identify molecular correlates of response, we performed molecular profiling of circulating free DNA (cfDNA) and tumor tissue.

METHODS: Plasma and tumor tissue samples were available from 130 and 118 pts in the lorlatinib arm, and from 125 and 104 pts in the crizotinib arm, respectively. Plasma DNA was analyzed for ALK fusions and mutations by next-generation sequencing (NGS; Guardant360, Guardant Health, Inc., Redwood City, CA, USA); tumor tissue DNA was analyzed with an ALK-mutation focused NGS panel (MolecularMD, Portland, OR, USA). Objective response rate (ORR), duration of response (DOR), and PFS were evaluated by blinded independent central review according to EML4-ALK variant type and ALK resistance mutation status.

RESULTS: At screening, 19 ALK missense mutations and 1 deletion were detected in plasma of 11 pts (5 and 6 in the lorlatinib and crizotinib arms, respectively). Most pts harbored 1 mutation, but 3 pts harbored ≥3 mutations. ALK fusions were detected in plasma of 48% of pts. EML4-ALK variants 1, 2, and 3 were detected in 14.6%, 5.4%, and 13.8% and in 20.0%, 1.6%, and 16.8% of pts, in the lorlatinib and crizotinib arms, respectively. Variants 4, 5, 7, and 8 were detected in 11.5% and 7.2% of pts, and less frequent fusion partners in 1.5% and 3.2% of pts, respectively. ORRs were generally higher in the lorlatinib arm vs the crizotinib arm, regardless of variant subtypes and/or mutational status, with no striking differences between EML4-ALK variants 1, 2, and 3 (range, 72% to 86% for lorlatinib and 50% to 76% for crizotinib). Median DOR and PFS were not reached for variants 1 and 3 in the lorlatinib arm, and ranged from 5.7 to 6.5 months, and from 7.4 to 7.6 months in the crizotinib arm, respectively.

CONCLUSION: Pts with untreated ALK+ advanced NSCLC had higher ORRs and potentially longer DOR and PFS across predefined biomarker subgroups when treated with lorlatinib compared with crizotinib in a phase 3 CROWN study. Based on pretreatment cfDNA analysis, lorlatinib led to similar clinical benefit regardless of the type of EML4-ALK variant or presence of ALK kinase mutations.

REFERENCE: 1. Shaw AT, et al. N Engl J Med. 2020;383:2018-2029.

Citation Format: Alessandra Bearz, Jean-François Martini, Jacek Jassem, Sang-We Kim, Gee-Chen Chang, Alice Shaw, Deborah Shepard, Elisa Dall'O', Anna Polli, Holger Thurm, Gerard Zalcman, Maria Rosario Garcia Campelo, Konstantin Penkov, Hidetoshi Hayashi, Benjamin J. Solomon. Efficacy of Lorlatinib in Treatment-Naïve Patients (pts) With ALK-Positive Advanced Non-Small Cell Lung Cancer (NSCLC) in Relation to EML4-ALK Variant Type and ALK Mutations [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 LB043.

Outcomes of patients who progressed while receiving avelumab + axitinib (A + Ax) and received subsequent treatment (Tx) in JAVELIN Renal 101

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Background: There are limited data on the outcomes of patients receiving second-line (2L) therapy following immunotherapies plus tyrosine-kinase inhibitors in the first-line (1L). We describe the outcomes of patients with advanced renal cell carcinoma (aRCC) who had received 1L A + Ax in the phase 3 JAVELIN Renal 101 trial and went on to receive subsequent Tx. Methods: At the cutoff date for the third interim analysis (April 28, 2020), patients who received 1L A + Ax (n = 442) and received any subsequent lines of Tx were assessed. We report the overall survival (OS), progression-free survival on next-line systemic therapy (PFS2) per type of Tx, and duration of 2L Tx. Results: Anticancer drug therapies were received by 204/442 patients following A + Ax Tx. Of patients who received a follow-up anticancer drug Tx, 163/204 received a single agent (SA), and 41/204 received a combination Tx (CT) regimen. The most common 2L SA was cabozantinib (60/163), and the most frequent 2L CT was everolimus + lenvatinib (12/41). OS, PFS2, and duration of treatment (DOT) for the various subgroups are summarized in the table below. Analyses on additional subgroups will also be presented. Conclusions: In patients with aRCC who received 2L CT following 1L treatment with A + Ax, long-term OS and PFS2 were observed. Clinical trial information: NCT02684006. [Table: see text]

Efficacy of avelumab + axitinib (A + Ax) versus sunitinib (S) by IMDC risk group in advanced renal cell carcinoma (aRCC): Extended follow-up results from JAVELIN Renal 101

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Background: In the phase 3 JAVELIN Renal 101 trial (NCT02684006), treatment-naive patients with aRCC receiving A + Ax showed improved progression-free survival (PFS) and objective response rate (ORR) across International Metastatic RCC Database Consortium (IMDC) risk groups (favorable [F], intermediate [I], and poor [P]) compared with patients receiving S. Here we report updated efficacy results for A + Ax vs S by IMDC risk groups from the third interim analysis. Methods: Patients were randomized 1:1 to receive either A (10 mg/kg intravenously every 2 weeks) plus Ax (5 mg orally twice daily) or S (50 mg orally once daily) for 4 weeks (6-week cycle). Patients were categorized per IMDC risk group into F, I, and P subgroups, and outcomes were assessed for F, I, P, and I + P. Overall survival (OS) and PFS, ORR, complete response (CR), and duration of response (DoR) per investigator assessment (RECIST v1.1) were assessed. Results: The study enrolled 886 patients with aRCC. At data cutoff (Apr 2020), median (95% CI) follow-up for OS in the A + Ax was NR (42.2-NE) vs 37.8 (31.4-NE) months with S. The Table shows OS, PFS, ORR, CR, and DOR by IMDC risk group. A + Ax generally showed improved efficacy compared with S across IMDC groups. Conclusions: Consistent with previously reported results from prior interim analyses, extended follow-up confirms the efficacy benefits of A + Ax vs S across IMDC risk groups in patients with aRCC. Patients continue to be followed up for the final OS analysis. Clinical trial information: NCT02684006. [Table: see text]

Veliparib in Combination with Carboplatin and Etoposide in Patients with Treatment-Naïve Extensive-Stage Small Cell Lung Cancer: A Phase 2 Randomized Study

PURPOSE

This study investigated the efficacy and safety of oral PARP inhibitor veliparib, plus carboplatin and etoposide in patients with treatment-naïve, extensive-stage small cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

Patients were randomized 1:1:1 to veliparib [240 mg twice daily (BID) for 14 days] plus chemotherapy followed by veliparib maintenance (400 mg BID; veliparib throughout), veliparib plus chemotherapy followed by placebo (veliparib combination only), or placebo plus chemotherapy followed by placebo (control). Patients received 4-6 cycles of combination therapy, then maintenance until unacceptable toxicity/progression. The primary endpoint was progression-free survival (PFS) with veliparib throughout versus control.

RESULTS

Overall (N = 181), PFS was improved with veliparib throughout versus control [hazard ratio (HR), 0.67; 80% confidence interval (CI), 0.50-0.88; P = 0.059]; median PFS was 5.8 and 5.6 months, respectively. There was a trend toward improved PFS with veliparib throughout versus control in SLFN11-positive patients (HR, 0.6; 80% CI, 0.36-0.97). Median overall survival (OS) was 10.1 versus 12.4 months in the veliparib throughout and control arms, respectively (HR, 1.43; 80% CI, 1.09-1.88). Grade 3/4 adverse events were experienced by 82%, 88%, and 68% of patients in the veliparib throughout, veliparib combination-only and control arms, most commonly hematologic.

CONCLUSIONS

Veliparib plus platinum chemotherapy followed by veliparib maintenance demonstrated improved PFS as first-line treatment for ED-SCLC with an acceptable safety profile, but there was no corresponding benefit in OS. Further investigation is warranted to define the role of biomarkers in this setting.

PIVOT-09: A phase III randomized open-label study of bempegaldesleukin (NKTR-214) plus nivolumab versus sunitinib or cabozantinib (investigator's choice) in patients with previously untreated advanced renal cell carcinoma (RCC)

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Background: Bempegaldesleukin (BEMPEG; NKTR-214) is a first-in-class interleukin-2 (IL-2) receptor pathway agonist that activates and expands effector T cells and natural killer cells in the tumor microenvironment and increases tumor PD-L1 expression, making BEMPEG a promising agent for combination with immune checkpoint inhibitors. In a phase 1/2 study, BEMPEG plus nivolumab (NIVO) demonstrated an encouraging objective response rate (ORR) in first-line advanced RCC (46%) and a manageable safety profile. BEMPEG plus NIVO offers a potential novel immunooncology treatment option for patients with advanced RCC. Methods: A global, multicenter, randomized, open-label phase 3 study is evaluating the efficacy and safety of BEMPEG plus NIVO vs investigator’s choice of tyrosine kinase inhibitor (TKI; sunitinib [SUNI] or cabozantinib [CABO]) in patients with previously untreated advanced or metastatic RCC with a clear-cell component. Patients must not have had prior systemic therapy (including neoadjuvant, adjuvant or vaccine therapy) for RCC. Key exclusion criteria include active brain metastasis and autoimmune disease requiring systemic immunosuppressive agents. Approximately 600 patients will be randomized 1:1 to receive 0.006 mg/kg BEMPEG plus 360 mg NIVO intravenously every 3 weeks or TKI (50 mg SUNI [4 weeks on, 2 weeks off schedule] or 60 mg CABO; orally each day). Patients will be stratified by International Metastatic RCC Database Consortium (IMDC) prognostic score (0 [favorable risk] vs 1-2 [intermediate risk] vs 3-6 [poor risk]) and TKI choice (SUNI vs CABO). Primary objectives are ORR by blinded independent central review (BICR) and overall survival in the IMDC intermediate/poor risk population and the intention-to-treat (ITT) population. Secondary objectives are progression-free survival by BICR in the IMDC intermediate/poor risk population and the ITT population, safety, PD-L1 expression as a predictive biomarker, and quality of life. Enrollment is ongoing. Clinical trial information: NCT03729245.

Biomarker analyses from JAVELIN Renal 101: Avelumab + axitinib (A+Ax) versus sunitinib (S) in advanced renal cell carcinoma (aRCC)

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Background: The phase 3 JAVELIN Renal 101 trial in previously untreated patients (pts) with aRCC demonstrated a progression-free survival (PFS) benefit and higher objective response rate with A+Ax vs S (Motzer, ESMO 2018; LBA6_PR). Here, we report outcomes from biomarker analyses of baseline tumor samples. Methods: We correlated efficacy with the results of molecular analyses of tissue samples from all 886 pts enrolled in JAVELIN Renal 101. Nephrectomy or tumor samples were characterized by immunohistochemistry (CD8 and PD-L1), whole-exome sequencing (WES), and RNAseq. WES and RNAseq were used to examine somatic mutations and analyze relevant gene expression signatures (GES) in relation to clinical outcomes. GES analyses included published and de novo signatures: effector T cell (Teff), angiogenesis (angio),T cell-inflamed (Tinf), and a novel immune-related signature incorporating pathway indicators for T- and NK-cell activation and IFNγ signaling, among others. Results: PD-L1 expression (≥1% immune cells) was associated with the longest PFS in the A+Ax arm and the shortest in the S arm (HR, 0.63; 95% CI, 0.49, 0.81). Significant treatment arm–specific differences in PFS were observed relative to wildtype when mutations in genes such as CD1631L, PTEN, or DNMT1 were present. Tumor mutational burden did not distinguish pts with respect to PFS. High-angio GES was associated with significantly improved PFS in the S arm but did not differentiate PFS in the A+Ax arm. In the low-angio subset, A+Ax improved PFS vs S. Pts with high Teff and Tinf in the A+Ax arm had longer PFS vs the S arm. In the A+Ax arm, PFS was enhanced in patients with immune GES–positive tumors vs those in the negative group (HR, 0.63; 95% CI, 0.46, 0.86; 2-sided p = 0.004), as well as in an independent dataset (JAVELIN Renal 100; Choueiri, Lancet Oncol, 2018) (HR, 0.46; 95% CI, 0.20, 1.05; 2-sided p = 0.064). Updated efficacy, including overall survival, will be presented. Conclusions: These findings define molecular features that differentiate therapy-specific outcomes in first-line aRCC and may inform personalized therapy strategies for pts with aRCC. Funding: Pfizer and Merck KGaA. Clinical trial information: NCT02684006.

Avelumab plus Axitinib versus Sunitinib for Advanced Renal-Cell Carcinoma

BACKGROUND

In a single-group, phase 1b trial, avelumab plus axitinib resulted in objective responses in patients with advanced renal-cell carcinoma. This phase 3 trial involving previously untreated patients with advanced renal-cell carcinoma compared avelumab plus axitinib with the standard-of-care sunitinib.

METHODS

We randomly assigned patients in a 1:1 ratio to receive avelumab (10 mg per kilogram of body weight) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were progression-free survival and overall survival among patients with programmed death ligand 1 (PD-L1)-positive tumors. A key secondary end point was progression-free survival in the overall population; other end points included objective response and safety.

RESULTS

A total of 886 patients were assigned to receive avelumab plus axitinib (442 patients) or sunitinib (444 patients). Among the 560 patients with PD-L1-positive tumors (63.2%), the median progression-free survival was 13.8 months with avelumab plus axitinib, as compared with 7.2 months with sunitinib (hazard ratio for disease progression or death, 0.61; 95% confidence interval [CI], 0.47 to 0.79; P<0.001); in the overall population, the median progression-free survival was 13.8 months, as compared with 8.4 months (hazard ratio, 0.69; 95% CI, 0.56 to 0.84; P<0.001). Among the patients with PD-L1-positive tumors, the objective response rate was 55.2% with avelumab plus axitinib and 25.5% with sunitinib; at a median follow-up for overall survival of 11.6 months and 10.7 months in the two groups, 37 patients and 44 patients had died, respectively. Adverse events during treatment occurred in 99.5% of patients in the avelumab-plus-axitinib group and in 99.3% of patients in the sunitinib group; these events were grade 3 or higher in 71.2% and 71.5% of the patients in the respective groups.

CONCLUSIONS

Progression-free survival was significantly longer with avelumab plus axitinib than with sunitinib among patients who received these agents as first-line treatment for advanced renal-cell carcinoma. (Funded by Pfizer and Merck [Darmstadt, Germany]; JAVELIN Renal 101 ClinicalTrials.gov number, NCT02684006.).