Progression-free Survival Benefit Research Articles

The efficacy of atezolizumab plus bevacizumab in the treatment of unresectable hepatocellular carcinoma in cirrhotic and non-cirrhotic patients.

e16214 Background: The IMbrave150 trial established that the combination of atezolizumab plus bevacizumab (AB) confers a significant progression-free survival (PFS) benefit when compared with sorafenib in patients with unresectable hepatocellular carcinoma (HCC). However, the nuanced impact of cirrhotic status on treatment response was not established by the study, leaving a critical aspect of patient stratification and outcomes yet to be fully understood. Methods: We conducted a retrospective single-center study of patients with HCC treated with AB between 2020 and 2023. Eligible patients were those who underwent at least one cycle of AB and had a follow-up period of at least three months post-AB initiation. Independent samples T-test and X2 and Fisher’s exact tests were used to evaluate associations between variables. PFS was calculated using the Kaplan-Meier method and compared according to cirrhotic status using the log-rank test. A Cox regression analysis was performed to estimate survival hazard ratios (HR). Results: Among 28 patients, the mean age at diagnosis was 64 years (SD 11), 18 (64%) were male, 26 (93%) had Child-Pugh (CP) class A liver function, and 18 (64%) were cirrhotic. Most patients presented with Barcelona Clinic Liver Cancer stage C disease (61%) and received AB in the first-line setting (93%). Clinicopathological features according to cirrhotic status are detailed in Table 1. With a median follow-up of 14 months (95% CI 8-20) since AB initiation, 16 progression events were recorded, resulting in a median PFS of 12 months (95%CI 6-18) for the entire cohort. Univariate analysis revealed an inferior median PFS in patients with cirrhotic HCC (7 months [95%CI 5-9] vs. not reached [p = 0.038]). However, in a multivariate Cox analysis, only obesity emerged as a significant predictor of an inferior PFS (HR 4.6; 95% CI 1.3 - 16.0, p = 0.018). Conclusions: In our study, cirrhosis was not associated with an inferior PFS. Notably, the majority of cirrhotic patients in this cohort exhibited CP A liver function, so uncertainties persist regarding the impact of cirrhosis on cancer progression in patients with CP B and C liver function. Further investigation is warranted to comprehensively evaluate whether cirrhotic, non-cirrhotic, and obese subgroups respond differently to AB therapy. [Table: see text]

Safety and efficacy of osimertinib plus bevacizumab as first-line treatment in EGFR-mutant NSCLC with brain metastases: A dynamic ctDNA-guided study.

e20606 Background: Non-small cell lung cancer (NSCLC) patients with positive driver genes had a higher incidence of brain metastasis. This study evaluates the efficacy and safety of Osimertinib combined with Bevacizumab as first line treatment in EGFR-mutant NSCLC with brain metastases, utilizing liquid biopsy and dynamic molecular detection to guide treatment strategies. This approach is anticipated to bring progression-free survival (PFS) benefits and shows different resistant mechanisms. Methods: We enrolled EGFR-mutant NSCLC patients with brain metastases receiving Osimertinib and Bevacizumab as first-line therapy. Paired plasma and cerebrospinal fluid (CSF) samples were collected at baseline, during stable disease, and at disease progression for Next-Generation Sequencing (NGS) analysis. The study's primary endpoints were central nervous system (CNS) PFS and objective response rate (ORR). Secondary endpoints included overall PFS, ORR, disease control rate (DCR), and safety. We also investigated resistance mechanisms to the combination therapy. Results: A total of 28 patients from Beijing TianTan Hospital (May 2020 - July 2023) were retrospectively enrolled. The average Bevacizumab treatment duration was 8.21 months (range: 1-27 months). CNS PFS was 26.73 months (95% CI, not reached), and overall PFS was 21.93 months (95% CI, 18.84-25.02 months). The CNS PFS for patients with 19del and L858R mutations were not reached and 26.73 months (95% CI, 15.11-38.35 months), respectively (p = 0.25). Patients undergoing intracranial local treatment showed a CNS PFS not reached, compared to 23.33 months (95% CI, 16.21-30.45 months) for those who did not (p = 0.417). The CNS ORR was 88%, ORR was 76%, and DCR was 100%. At the time of data cutoff (Dec 15th, 2023), 1 patient progressed in both lung and CNS metastases, 8 patients only progressed in lung, 8 patients only progressed in CNS metastases .EGFR C797S mutation was detected in 2 plasma sample, Met amplification in 1 tumor tissue, EGFR C719S mutation in 1 paired plasma-tumor tissue and PIK3CA in 2 plasma sample. Increasing abundance in TP53 and CDKN2A were detected in 2 paired plasma-tumor tissue. Adverse events of grade 3 or higher included one case (3.6%) of severe ulcerative colitis leading to Osimertinib discontinuation and two cases (7.1%) of bevacizumab discontinuation due to bleeding events. Conclusions: Osimertinib combined with Bevacizumab as a first-line treatment significantly prolonged CNS PFS in EGFR-mutant NSCLC patients with brain metastases, offering superior control over intracranial lesions compared to Osimertinib monotherapy (15.2 months, FLAURA study). This study underscores the potential of dynamic ctDNA monitoring in guiding effective treatment strategies for this patient population. Further research is warranted to explore the broader clinical implications of these findings.

Comparative patient-reported tolerability (PRT): A multiplicity-controlled analysis of LIBRETTO-531, a randomized controlled trial (RCT) in medullary thyroid cancer (MTC).

11111 Background: In cancers with longer natural histories, progression free survival (PFS) alone may not adequately capture the impact of treatment side effects (SE) and may, therefore, be complemented by robust measures of patient-reported tolerability (PRT) to quantify overall SE burden. Here, we pioneer the use of a novel, scalable, quantitative PRT metric as a key secondary endpoint to support the regulatory review and inform clinical decision-making of selpercatinib use in LIBRETTO-531 (NCT04211337), an RCT that demonstrated the PFS benefit (HR=0.28) of selpercatinib over vandetanib/cabozantinib (control) in RET-mutant MTC. Methods: We first assessed PRT using the single Functional Assessment of Cancer Therapy (FACT) item GP5, asking patients to rate “bothered by treatment side effects” from 0 to 4. Patients who reported “3=quite a bit” or “4=very much” on GP5 were classified as “high SE bother,” a validated meaningful cutoff for treatment SE burden. In a second pre-specified step, PRT was defined as the proportion of time on treatment (PTOT) with “high SE bother” and was compared between selpercatinib vs. control arms in the tolerability evaluable population. PRT was tested at a 1-sided significance level of 0.025, conditional on achieving statistical significance for PFS and treatment failure-free survival by BICR. To complement PRT, other patient-reported outcomes including health-related quality of life (HRQoL, using EORTC QLQ-C30) and symptomatic adverse events (AEs; using PRO-CTCAE) were evaluated. We calculated the PTOT that patients reported clinically meaningful impairment of HRQoL (using pre-specified cutoff scores) and highly symptomatic AEs (scores of 3 or 4). Results: Patients on selpercatinib (n=161) had a significantly better PRT (lower PTOT with high SE bother) than control (n=81) (8% vs. 24%, p<.0001). Sensitivity analyses using different cutoffs for high SE bother showed consistent results (p<.0001). On QLQ-C30, patients on selpercatinib reported significantly less PTOT with HRQoL impairment across physical (36% vs. 52%), role (2% vs. 11%), cognitive (4% vs. 8%), emotional (6% vs. 11%), and social (2% vs. 8%) functions (all p<0.01) vs. control. On PRO-CTCAE, patients on selpercatinib reported significantly less PTOT with diarrhea (5% vs. 38%), fatigue (6% vs. 21%), taste change (3% vs. 15%), decreased appetite (2% vs. 15%), hand/foot syndrome (2% vs. 9%) (all p<.001) vs. control. Conclusions: Through the incorporation of a novel, single question and quantifiable metric that measured time on treatment under high SE bother into the LIBRETTO-531 study, we demonstrated superior PRT and improved PFS for selpercatinib in patients with RET-mutant MTC versus vandetanib/cabozantinib. This simplified PRT metric deserves further adoption as a quantitative endpoint to complement PFS in future RCTs.

Bevacizumab combination therapy versus standard chemotherapy for ovarian cancer in shorter and longer followup duration: A systematic review and meta-analysis of randomized controlled trials.

e23296 Background: Bevacizumab is an anti-angiogenesis drug commonly added to standard chemotherapy regimens in the treatment of ovarian cancer. However, its comparative efficacy and safety in shorter and longer followup duration leaves a research gap that needs to be addressed. This systematic review and meta-analysis aims to evaluate the efficacy and safety of bevacizumab in patients with ovarian cancer in shorter and longer follow up duration. Methods: We searched Medline, Cochrane CENTRAL, Scopus, and Google Scholar for all phase 3 randomized controlled trials (RCTs) that administered bevacizumab to women with ovarian cancer. Review Manager 5.4 was used to calculate risk ratios (RR) and hazard ratios (HR) with 95% confidence intervals (95% CIs). We assessed the quality of included studies using version 2 of the Cochrane Risk of Bias tool (RoB 2). Results: After screening the titles, abstracts, and full texts, we included nine RCTs in our systematic review and meta-analysis. Four RCTs had low risk of bias while five had some concerns. Bevacizumab was associated with a progression free survival benefit for < 36 months (HR 0.59, 95% CI 0.45 to 0.76, p < 0.0001, I2= 90%) and > 36 months (HR 0.66, 95% CI 0.55 to 0.80, p < 0.0001, I2= 80%), and an overall survival benefit for < 36 months (HR 0.87, 95% CI 0.78 to 0.98, p = 0.02, I2= 0%) but not for > 36 months (HR 0.98, 95% CI 0.89 to 1.09, p = 0.77, I2= 30%). There was no difference in deaths between intervention and control groups < 36 months (RR = 0.95, 95% CI 0.86 to 1.04, p = 0.26, I2= 10%) or > 36 months (RR 1.02, 95% CI 0.97 to 1.06, p = 0.50, I2= 0%). Bevacizumab reduced disease progression < 36 months (RR 0.82, 95% CI 0.72 to 0.92, p = 0.0008, I2= 82%) but not at > 36 months (RR 0.83, 95% CI 0.58 to 1.19, p = 0.30, I2= 94%). The adverse events reported with Bevacizumab use included thrombocytopenia, neutropenia, leukocytopenia, anemia, hypertension, bleeding or hemorrhage, and gastrointestinal, cardiac, and dermatological adverse events. Conclusions: Bevacizumab may improve progression free survival within and after 36 months, overall survival within 36 months, and reduce disease progression within 36 months. Future studies should explore the long-term effectiveness of bevacizumab in diverse patient populations and focus on individual patient-tailored treatment approaches to optimize outcomes.

Survival benefit with regorafenib and/or trifluridine/tipiracil sequencing to rechallenge with anti-EGFR-based third-line regimens in metastatic colorectal cancer: A multicenter retrospective real-world subgroups comparison.

e15553 Background: Rechallenge with anti-EGFR drugs has recently proven therapeutic activity in a subset of RAS wild type (wt) metastatic colorectal cancer (mCRC) patients who had previously benefited from cetuximab- or panitumumab-based first-line regimen. Regorafenib (R) and Trifluridine/tipiracil (T) have been found to improve survival in patients with refractory mCRC. This real-life subgroup survival analysis focused on treatment with R and T, sequential or not, in patients who had received prior third-line anti-EGFR therapy. Methods: Clinical data of patients diagnosed with mCRC who received R and/or T between July 2012 and March 2022, were retrospectively collected from 13 Italian cancer institutes. The objective of this subgroup analysis was to compare overall survival (OS) and progression-free survival (PFS) in patients who received late-line R and/or T according to prior third-line anti-EGFR-based treatment. Results: The entire study enrolled 866 patients. 146 (16.8%) of them received the T/R sequence (T/R), 116 (13.3%) the reverse sequence (R/T), 325 (37.5%) T, and 279 (32.5%) R. For the purpose of this subgroup analysisi we identified 338 RAS wt patients (39%) who were eligible. Of these, 290/338 patients (85.8%) did not receive the previous third-line anti-EGFR therapy, while 48 patients (14.2%) did it (12 T/R, 10 R/T, 13 T, 13 R). When comparing T/R to R/T in patients who did not previously received third-line anti-EGFR drug rechallenge, we observed a statistically significant and clinically meaningful improvement in PFS. In detail, the median PFS benefit was 67,5% when treating patients with T/R sequence vs. the reverse sequence (11,4 vs. 3,7 months, respectively, ∆ = 7,7 months; p = < 0,0001; HR = 0,17; 95% CI = 0,09-0,32). In patients who received T/R or R/T following rechallenge with anti-EGFR drug, we also observed a comparable, albeit smaller and non-statistically significant, improvement in PFS (8.1 vs. 7.8 months, respectively; p = 0.22; HR 0,51; 95% CI = 0,17-1,50). There were no statistically significant differences in OS between these groups. Anti-EGFR rechallenge data analysis showed that the non-sequential administration of R and T had no statistically significant impact on survival outcomes. Conclusions: With the limit of the sample size, our retrospective subgroup analysis failed to validate the promising beneficial effects of anti-EGFR rechallenge prior to R and/or T treatment. A statistically significant longer PFS was only observed in patients with refractory metastatic colorectal cancer receiving T/R sequence without prior cetuxumab- or panitumumab-based regimens.

Efficacy and safety of eribulin-based chemotherapy in patients with advanced breast cancer: A single-centre retrospective study.

e13121 Background: Eribulin, a nontaxane microtubule dynamics inhibitor, which was approved for the third-line treatment of advanced breast cancer (ABC) in China in 2019. This retrospective study aimed to assess efficacy and safety of Eribulin-based chemotherapy in ABC patients, especially for patients exhibiting HER2-0 and HER2-low status (immunohistochemistry [IHC] 1+ or IHC 2+with a negative in situ hybridization assay). Methods: This single-center retrospective study planned to include 126 ABC patients from January 2020 to December 2023. Enrolled participants received Eribulin either as monotherapy or in combination with other regiments such as anti-angiogenic therapy, PD-1 inhibitor, or alternative chemotherapy in clinical practice. The primary outcomes included progression-free survival (PFS) and safety assessments. Results: A total of 84 patients with ABC received Eribulin were enrolled. Patients' baselines were summarized as follows: The median age was 53.3 years (range 30.0–86.0 years). 53 (63.1%) patients were HER2-low while 40 (47.6%) patients were hormone receptor (HR) positive. 63.1% patients have received at least one line chemotherapy before the use of Eribulin. According to the K-M survival analysis, the median PFS was 6.0 (range 3.2-11.3) months for all patients. The median PFS was longer for patients received aromatase inhibitors (AI) for over 6 months than patients with AI naive (median 10.1 vs 6.6 months; p=0.192) in HR positive patients. Patients who received CDK4/6 therapy had longer PFS than patients (median 10.7 vs 6.6 months; p=0.38). There was a trend toward prolonged PFS in the HER2-0 group compared with HER2-low group (median 10.13 vs 6.03 months; p=0.154), although there was no significant difference. A nonsignificant improvement of PFS was observed in HR-/HER2-0 patients, compare with HR-/HER2-low patients (median 16.4 vs 4.7mo; p=0.21). Meanwhile the median PFS of HER2-0 and HER2-Low was similar in HR positive patients. The objective response rate was 35.5% in HER2-0 group and 30.2% in HER2-low group. In multivariate cox regression, Eribulin as first line treatment (HR, 4.028; 95% CI, 1.131-14.337) and HER2-0 (HR, 2.903; 95% CI, 1.257-6.702) showed prognostic values regarding PFS. Common grade 3 or 4 adverse events that were reported in more than 10% were neutropenia (41.6%) and leukopenia (26.2%). No treatment-related deaths were reported. Conclusions: This single-center study demonstrated encouraging efficacy and safety in the ABC patients treated with Eribulin. Significant PFS benefit was associated with Eribulin treatment in patients with HER2-0 compared with HER2-low. This study still needs longer follow-up to evaluate its efficacy more comprehensively.

Efficacy and safety of SOX regimen combined with inetetamab as first-line treatment for HER2-positive advanced gastric cancer.

e16028 Background: Patients with HER2-positive advanced gastric cancer have a poor prognosis. Trastuzumab combined with chemotherapy is the first-line standard treatment. Inetetamab is a novel anti-HER2 drug, and its efficacy and safety in gastric cancer have not been reported yet. Methods: Thirty-eight patients with HER2-positive advanced gastric cancer or gastroesophageal junction adenocarcinoma were randomly divided into two groups: one group received inetetamab combined with the SOX regimen, and the other group received trastuzumab combined with the SOX regimen. After 4-6 cycles, patients with stable disease received maintenance therapy. The primary endpoints were progression-free survival (PFS) and overall survival (OS), and the secondary endpoints were the objective response rate (ORR), disease control rate (DCR), and adverse events (AEs). Results: Thirty-seven patients completed the trial, with 18 patients in the inetetamab group and 19 patients in the trastuzumab group. In the inetetamab group, the median PFS was 8.5 months, compared to 7.3 months in the trastuzumab group (P = 0.046), indicating a significant difference. The median OS was 15.3 months vs. 14.3 months (P = 0.46), and the ORR was 50% vs. 42% (P = 0.63), with no significant differences between groups. Common AEs included leukopenia, thrombocytopenia, nausea, and vomiting. The incidence rates of grade ≥ 3 AEs were 56% in the inetetamab group and 47% in the trastuzumab group (P = 0.63), with no significant difference. Conclusions: In the first-line treatment of HER2-positive advanced gastric cancer, the efficacy of inetetamab and trastuzumab was comparable. The inetetamab group had superior PFS benefits, and both groups had good safety.

Evaluating the significance of next-generation sequencing (NGS) testing in Indian patients with advanced malignancies: An observational study on clinical outcomes and treatment costs.

e15091 Background: The widespread use of Next-Generation Sequencing (NGS) panels to guide targeted therapy in advanced malignancies has raised questions regarding their real-world impact on clinical outcomes and affordability. Methods: This observational study included 126 patients, conducted between January 2022 and December 2023 aimed to assess the utility of NGS testing in both the initial and subsequent lines of treatment for Indian patients facing advanced malignancies. Results: In the first-line setting, NGS was extensively employed for patients with metastatic Colorectal Cancer (mCRC) and Non-Small Cell Lung Cancer (NSCLC). Analysis of RAS and BRAF mutations in mCRC patients (n=21) informed the choice between EGFR and VEGFR-directed therapy, resulting in a median Progression-Free Survival (PFS) of 7.5 months. In NSCLC patients (n=37), the NGS identified targetable mutations in 30 cases, leading to significantly improved mPFS (12 months vs 6 mo with chemotherapy alone). NGS was also employed for HRR, HRD and BRCA testing in advanced breast (n=45) and ovarian carcinoma (n=11), which helps in determining prognosis, role of targeted therapy and genetics. No adverse events noted till date. For patients undergoing subsequent lines of treatment (n=12), NGS detected targetable mutations in 9 cases. NGS revealed actionable mutations (ERBB2, CD74/NRG1fusion and KRAS12C mutation) in metastatic NSCLC patients (n=3), leading to appropriate treatment and PFS of 4-6 months. In metastatic NSCLC patients, T790M mutation was detected in 1 patient confering PFS of 6 months with change to Osimertinib and EGFR exon 20 insertion mutation detected in another, survival didn't improve with addition of amivantamab due to poor general condition. Alpelisib was started for PIK3CA mutation in metastatic Ca Breast (HR+,HEr2-), which was discontinued due to poor tolerance after 3 months. In Metastatic Neuroendocrine Carcinoma (NEC) Lung, detection of EGFR l858R mutation did not confer a PFS benefit despite the addition of Geftinib to chemotherapy. Due to financial constraints, targeted therapy couldn't be started for 2 patients with pathogenic target detected. Conclusions: The study's findings suggest that NGS testing offers tangible clinical benefits in both initial and subsequent lines of treatment for advanced malignancies in the Indian population. Despite the varying costs of NGS in India (ranging from 240 to 1800 USD), the data implies an overall affordability, making it a viable option for patients with advanced malignancies. However, NGS didn't improve outcomes in patients with rapidly progressing disease, poor general condition and financial constraints.

Efficacy and safety of time-of-day infusion of pemetrexed plus platinum and paclitaxel plus platinum for patients with advanced non-small cell lung cancer: A retrospective study.

e20557 Background: Retrospective studies suggest that administering chemotherapy infusions in the morning can enhance treatment efficacy and mitigate side effects in non-small cell lung cancer (NSCLC) patients. However, the effectiveness of chronotherapy using pemetrexed plus platinum (AP) and paclitaxel plus platinum (TP) in advanced NSCLC chemotherapy remains unexplored. This study aims to evaluate the impact of AP and TP chrono-chemotherapy (CCT) on treatment response and adverse events in advanced NSCLC patients. Methods: We retrospectively analyzed 78 advanced NSCLC patients treated with AP (AP cohort) and 50 advanced NSCLC patients treated with TP (TP cohort) at Guangdong Second Provincial General Hospital from 2018 to 2021. Based on previous research, we classified patients who received chemotherapy infusions more than twice after 2:00 PM as the afternoon (PM) group, while the rest were categorized as the morning (AM) group. Treatment response was evaluated using the Response Evaluation Criteria in Solid Tumors Criteria V.1.1. The primary endpoint was progression-free survival (PFS). All adverse events were identified and graded according to the National Cancer Institute-Common Terminology Criteria for Adverse Events version 5.0. Results: In the AP cohort, the AM group exhibited a longer PFS compared to the PM group (AM vs. PM, n = 26 vs. n = 52, 43.0 vs. 13.0 months, p = 0.001). However, no significant difference was observed in PFS in the TP cohort (AM vs. PM, n = 23 vs. n = 27, 11.0 vs. 22.0 months, p = 0.501). Subsequent subgroup analysis in the AP cohort favored the AM group across all major subgroups for PFS treatment effect. In contrast, the TP cohort subgroups showed a PFS benefit only in the smoking patients of the PM group. Furthermore, the analysis of adverse reactions revealed similar incidences of any treatment emergent adverse events (TEAE) in both AP and TP cohorts (AM vs. PM, 92.3% vs. 86.5% in AP cohort and 95.7% vs. 100.0% in TP cohort), and grade 3 TEAEs (AM vs. PM, 34.6% vs. 21.2% in AP cohort and 39.1% vs. 29.63% in TP cohort). The most common adverse events were anemia (73.1%), leukopenia (57.7%), and elevated ALT (46.2%) in AP cohort and anemia (100%), leukopenia (65.2%), and hypoalbuminemia (47.8%) in TP cohort. Univariate and multivariate analyses indicated that afternoon infusion of AP chemotherapy (p = 0.009) was an independent prognostic factor for NSCLC. Conclusions: AP treatment administered in the morning may enhance PFS in advanced NSCLC, while TP remains unaffected. This suggests that CCT could potentially enhance the efficacy of individualized chemotherapy in advanced NSCLC.

Association of patient (pt) factors and pharmacodynamic biomarkers with progression-free survival (PFS) after idecabtagene vicleucel (ide-cel) in pts from KarMMa-3.

7527 Background: Ide-cel, a B-cell maturation antigen (BCMA) CAR T cell therapy (tx), significantly improved PFS vs standard regimens in pts with triple-class–exposed relapsed or refractory MM (13.8 vs 4.4 mo, P<0.001) in KarMMa-3. Median PFS in the ide-cel treated population (pop; n=225) was 15.7 (95% CI, 12.5–18.9) mo (Rodríguez-Otero ASH 2023). PFS benefit of ide-cel was consistent across high-risk pt subgroups. Previous analyses indicated that lower levels of baseline soluble BCMA (sBCMA; measure of tumor burden) and lower basal inflammatory markers were positively associated with response to ide-cel. This analysis identified pre- and post-tx pt factors and pharmacodynamic biomarkers associated with longer PFS with ide-cel in the treated pop. Methods: Median PFS (15.7 mo) of the treated KarMMa-3 pop was used to divide pts into 2 groups: longer PFS (>15.7 mo; n=106) or shorter PFS (≤15.7 mo; n=110). Censored pts (n=9) who had a PFS <15.7 mo were excluded. Pre- and post-tx values for laboratory parameters, MM assessments, sBCMA, inflammatory cytokines, ide-cel transgene persistence, and minimal residual disease (MRD; 10−5 sensitivity) were evaluated. Serum free light chains (sFLCs) were evaluated as biomarkers of plasma cell clearance; clearance was defined as level below limit of detection of both involved and heterotypic sFLC. Analyses were post hoc and exploratory; statistical tests were used to identify relationships of interest. Results: In total,94% of pts with longer PFS achieved a best overall response of ≥very good partial response and had lower levels of β-2 microglobulin ( P<0.01), lactate dehydrogenase ( P<0.01), and sBCMA ( P<0.01) at baseline. Inflammatory markers (eg, tumor necrosis factor, ferritin, C-reactive protein) were significantly higher ( P<0.05) in pts with shorter vs longer PFS at baseline. All pts with longer PFS (100%) achieved sFLC clearance after ide-cel infusion. Among pts who achieved initial clearance, pts with longer PFS had a longer duration of sFLC clearance than shorter PFS ( P<0.001), suggesting more durable engraftment of ide-cel and tumor control. Within MRD-evaluable pts, those with longer PFS achieved higher MRD negativity vs shorter PFS (87% vs 41%) at 6 mo post infusion with sustained MRD negativity (53% vs 4%) lasting 8–12+ mo. No apparent relationship was observed between PFS and ide-cel persistence at 6-, 9- and 12-mo post-infusion. Conclusions: Pts with longer PFS after ide-cel infusion had relatively lower tumor burden and lower levels of peripheral inflammatory markers before tx, highlighting the importance of managing baseline tumor burden before CAR T cell infusion to achieve optimal response. Complete and sustained clearance of sFLCs within the first few mo post infusion was associated with longer PFS. MRD negativity at 6 mo and sustained MRD negativity were enriched in pts with longer PFS. Clinical trial information: NCT03651128 .

Ivonescimab combined with chemotherapy in patients with EGFR-mutant non-squamous non-small cell lung cancer who progressed on EGFR tyrosine-kinase inhibitor treatment (HARMONi-A): A randomized, double-blind, multi-center, phase 3 trial.

8508 Background: Ivonescimab (AK112/SMT112) is a anti-PD-1/VEGF bispecific antibody. Previous phase I/II clinical studies have shown potential efficacy of ivonescimab in NSCLC patients with EGFR mutations who had failed prior EGFR-TKIs therapies. This phase 3 study aimed to evaluate and confirm the efficacy and safety of ivonescimab combined with chemotherapy versus chemotherapy alone in this population. Methods: Patients were randomized 1:1 to receive ivonescimab (20 mg/kg) plus pemetrexed (500 mg/m2) and carboplatin (AUC 5) or placebo plus chemotherapy once every 3 weeks for four cycles, with stratification according to the third-generation EGFR-TKI (received vs not received) and brain metastases (presence vs absence), followed by maintenance therapy of ivonescimab and pemetrexed or placebo and pemetrexed. The primary endpoint was progression-free survival (PFS) in intention-to-treat (ITT) population assessed by independent radiographic review committee (IRRC) per RECIST v1.1. Here we report the results of the first planned interim analysis. Results: Total 322 patients were randomized (161 to the ivonescimab plus chemotherapy arm, 161 to the placebo plus chemotherapy arm). 86.3% versus 85.1% of patients had received the third generation EGFR-TKIs treatment, 21.7% versus 23.0% of patients had brain metastases. As of March 10, 2023, median follow up time was 7.89 months. PFS was significantly improved in the ivonescimab plus chemotherapy arm (HR 0.46 [0.34, 0.62], P < 0.0001). Median PFS (95%CI) by IRRC were 7.06m (5.85, 8.74) in the ivonescimab arm versus 4.80m (4.21, 5.55) in chemotherapy arm. The prespecified subgroup analysis showed PFS benefit favoring patients receiving ivonescimab over placebo across almost all subgroups, including in patients who progressed on the third-generation EGFR-TKIs therapy (HR 0.48, 95% CI 0.35-0.66), those with brain metastases (HR 0.40, 0.22-0.73), those with EGFR mutation of deletion 19 (HR 0.48, 0.32-0.73), and individuals with T790M mutation positive (HR 0.22, 0.09-0.54). The ORR were 50.6% and 35.4%, respectively. Grade ≥3 TEAEs occurred in 99 (61.5%) patients versus 79 (49.1%) patients, the most common grade ≥3 TEAEs were chemotherapy related adverse events. Grade ≥3 immune-related adverse events occurred in 10 (6.2%) patients versus 4 (2.5%). Grade ≥3 VEGF blocking related adverse events occurred in 5 patients (3.1%) versus 4 patients (2.5%). Conclusions: Ivonescimab plus chemotherapy significantly improved PFS while maintaining a manageable safety profile in patients who had failed EGFR-TKIs treatments. Clinical trial information: NCT05184712 .

Regorafenib Plus for third-line treatment in metastatic colorectal cancer: A real-world study.

e15562 Background: Regorafenib, approved as a monotherapy for refractory metastatic colorectal cancer (mCRC), is recognized for its potential immunomodulatory effects and ability to reverse chemotherapeutic resistance. In response to this, a combination regimen known as regorafenib Plus has been customized for specific patients. This study aims to evaluate the effectiveness and safety of regorafenib as a standalone treatment and in combination with other therapies (including concurrent/sequential chemotherapy, immunotherapy, transarterial chemoembolization [TACE]) in the real-world setting. The goal is to present viable treatment options for patients with mCRC. Methods: In this retrospective study, patients with chemo-refractory metastatic colorectal cancer (mCRC) who underwent regorafenib treatment at Beijing Chaoyang Hospital between January 2018 and October 2023 were stratified into two cohorts: monotherapy (Rego Mono) and concurrent/sequential combination therapy (Rego Plus). Index date was the initiation of regorafenib therapy in a sequence and median follow-up was 19.1 months. The clinical outcomes included progression-free survival (PFS), overall survival (OS), and 1/2-year OS rates. Results: A total of 67 pts were included (n = 39 Rego Mono; n = 28 Rego Plus). Baseline characteristics were comparable between cohorts. The median progression-free survival (PFS) was significantly extended in the Rego Plus group compared to Rego Mono (8.0 vs. 3.6 months, P = 0.000), and overall survival (OS) was also notably prolonged (24.4 vs. 19.1 months, P = 0.046). The 1/2-year OS rates were also improved by Rego Plus (63% vs 37.1%, 25.5% vs 11.4%). However, there were no statistical differences in PFS between concurrent and sequential combination therapies (8.4 vs 8.0 mont). Notably, under sequential therapy, after 3.7 months of PFS with regorafenib alone, an additional 4.7 months of PFS was observed when combined therapy was introduced. Regarding safety, Rego Plus was associated with an increased rate of adverse events (AEs) without an escalation in severity. Common AEs included rash, hand-foot syndrome, hypertension, and diarrhea. Conclusions: Rego Plus significantly prolonged PFS and OS in patients with chemo-refractory mCRC. Particularly when tumor stabilization is evident during monotherapy, the introduction of Rego Plus can offer a comparable or even longer PFS benefit, nearly doubling the PFS. Despite an elevated rate of AEs, the severity of these events did not increase, suggesting good tolerability. This approach has the potential to enhance the effectiveness of existing third-line therapies for mCRC, ultimately contributing to an improved prognosis for patients.

Association of baseline characteristics with adverse events (AEs) in the PROpel trial of olaparib (ola) plus abiraterone (abi) as first-line (1L) treatment for metastatic castration-resistant prostate cancer (mCRPC).

e17030 Background: The PROpel trial (NCT03732820) met its primary endpoint and showed a statistically significant radiographic progression-free survival benefit (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.54–0.81; P<0.0001) with ola + abi vs placebo + abi in 1L mCRPC; whilst not statistically significant, overall survival (OS) was numerically prolonged (median 42.1 vs 34.7 months; HR 0.81, 95% CI 0.67–1.00; P=0.0544). To further inform clinical decision making, we provide exploratory post hoc analysis investigating the relationship between selected patient baseline characteristics and AEs for ola + abi. Methods: Anemia and venous thromboembolism events (VTEs) were identified as the only grade (Gr) ≥3 AEs or AEs of special interest reported in >20 (>5.0%) patients (pts) in the ola + abi arm (data cutoff 12 Oct 2022). Baseline characteristics were correlated with AEs using Cox regression by backwards elimination and analysis with AEs as dependent variables. Baseline characteristics assessed included: age (<70 or ≥70 y), time since diagnosis (<median or ≥median) , ECOG status (0 or 1), metastatic sites (visceral [yes or no], bone only [yes or no]), number of bone metastases (0, 1–4, 5‒9, 10‒20 or >20), Gleason score (<9 or 9–10), homologous recombination repair mutation status (HRRm, non-HRRm or unknown), race (white or non-white), prior docetaxel at metastatic hormone-sensitive prostate cancer (yes or no), pain (symptomatic or asymptomatic/mildly symptomatic), type of progression (prostate-specific antigen [PSA], radiographic or both), prior radiotherapy (yes or no) and albumin, creatinine, lactate dehydrogenase, alkaline phosphatase (ALP), hemoglobin (10<12 or ≥12) and log PSA levels. Results: 398 pts received ola + abi. 64 (16.1%) had Gr ≥3 anemia and 34 (8.5%) a VTE. Baseline characteristics correlated significantly with increased risk of these AEs as shown (Table); characteristics not shown were not associated with AEs. Conclusions: These results provide insight into which baseline characteristics correlate with the risk of Gr ≥3 anemia. Pts with abnormal ALP, pre-existing anemia, ECOG PS 1 or age ≥70 years could be at higher risk and the development of Gr ≥3 anemia during treatment with ola + abi should be monitored. Clinical trial information: NCT03732820 . [Table: see text]

FURTHER: A global study to evaluate furmonertinib in patients with EGFR mutant NSCLC including uncommon EGFR mutations (FURMO-002).

TPS8666 Background: Furmonertinib (AST2818) is an oral, highly brain-penetrant, and broadly active mutation-selective epidermal growth factor receptor ( EGFR) inhibitor engineered for broad activity and selectivity across EGFRmutations (mts) (1). Furmonertinib is approved in China for first-line advanced NSCLC with EGFR Ex19del or L858R mts based on the progression-free survival benefit observed in the Phase 3 study versus gefitinib (FURLONG). Furmonertinib has also demonstrated promising interim efficacy and safety in patients (pts) with NSCLC harboring EGFR exon 20 insertion (ex20ins) mts with a confirmed overall response rate (ORR) of 78.6% (n=28) by blinded independent central review (BICR) and a preliminary median duration of response (DoR) of 15.2 months in the front-line setting (FAVOUR study; see Han et al., WCLC 2023). Furmonertinib recently obtained FDA Breakthrough Therapy Designation for the treatment of pts with advanced NSCLC with EGFR ex20ins mts. P-loop and αC-helix Compressing (PACC) mts represent another subset of uncommon EGFR mts (2) that are similar to ex20ins mts in narrowing the drug-binding pocket; including G719X, S768I, E709X, L747X, V774M. Preclinical data indicating that furmonertinib is potent in models harboring EGFR PACC mts Developing efficacious, well-tolerated, and CNS-penetrant medicines for NSCLC pts with EGFR ex20ins mts and PACC mts remains an unmet need. Methods: FURTHER (FURMO-002) is the first global trial evaluating furmonertinib in NSCLC pts with EGFR and HER2 mts in North America, Europe, and the Asia-Pacific. FURTHER is a phase 1b, open-label, multicenter study in which pts will be treated orally with furmonertinib daily. For Stage 1 dose-escalation, the primary endpoint is incidence and severity of adverse events, including dose limiting toxicities and has been completed. For Stage 2 dose expansion, approximately 120 pts will be enrolled across 4 expansion cohorts. Stage 2 Cohorts 1-3 dose expansion cohorts will enroll pts with previously treated, locally advanced or metastatic NSCLC pts with either EGFR ex20ins mts, HER2 ex20ins mts, or EGFR activating mts, respectively. Cohorts 1-3 allow enrollment of pts with prior EGFR or HER2-directed therapy. Stage 2 Cohort 4 will enroll EGFR TKI-naïve NSCLC pts with EGFR PACC mts. Key inclusion criteria include documented EGFR or HER2 mts by local testing and measurable disease per RECIST v1.1. Stage 2 primary endpoint is ORR using RECIST v1.1. Key secondary endpoints include progression-free survival and overall survival. Stage 2 enrollment is ongoing. 1. Musib et al., NACLC 2022. 2. Robichaux et al., 2021. Clinical trial information: NCT05364073 .

Patient-reported outcomes (PROs) from the DREAMM-7 randomized phase 3 study comparing belantamab mafodotin, bortezomib, and dexamethasone (BVd) vs daratumumab, bortezomib, and dexamethasone (DVd) in patients with relapsed/refractory multiple myeloma (RRMM).

7543 Background: Belantamab mafodotin(belamaf), a first-in-class antibody-drug conjugate targeting B-cell maturation antigen, acts through a multimodal mechanism including direct cell killing and immune-mediated mechanisms. The global, phase 3, open-label, randomized, DREAMM-7 trial (NCT04246047) met its primary endpoint of demonstrating statistically significant progression-free survival benefit favoring BVd vs DVd in patients with RRMM who had received ≥1 prior line of therapy; here, we report PRO findings for BVd vs DVd. Methods: Patients were randomized (1:1) to receive BVd or DVd and completed electronic PRO measures at baseline and every 3 weeks (Q3W) during treatment. PRO measures included EORTC-QLQ-C30, EORTC-QLQ-MY20 disease symptoms (pain), PRO-CTCAE patient-reported tolerability, and OSDI vision-related functioning (Q3W up to the sixth dose of belamaf, then Q6W). Each domain was summarized using descriptive statistics. Results: Among 494 patients (BVd, n=243; DVd, n=251), adherence to PRO assessments was >90% for most study visits. There was no difference in EORTC QLQ-C30 global health status/quality-of-life assessments between the study arms over time. Similarly, role functioning, physical functioning, fatigue, and pain were stable (change from baseline in EORTC score was within 10 points) over time and consistent between arms. Most symptomatic adverse events evaluated by PRO-CTCAE were reported at no to low severity, frequency, and interference (PRO-CTCAE ratings ≤2) in both arms throughout the study. The severity and interference of blurred vision and frequency of watery eyes were reported at higher levels (PRO-CTCAE ratings ≥3) in the BVd arm. Among patients in the BVd arm with a clinically meaningful deterioration in vision-related functioning (a change from baseline of ≥12.5 points), EORTC-QLQ-C30 global health status, role functioning, and physical functioning were comparable to the DVd arm over time. Conclusions: Overallquality of life, role functioning, physical functioning, fatigue, and pain were comparable in patients treated with BVd vs DVd. In patients treated with BVd who reported a clinically meaningful deterioration in vision-related functioning, overall quality of life was consistent with the DVd arm.

Final safety results from ATHENA–MONO (GOG-3020/ENGOT-ov45), a randomized, placebo-controlled, double-blind, phase 3 trial evaluating rucaparib monotherapy as maintenance treatment in patients with newly diagnosed ovarian cancer.

5554 Background: Rucaparib provided a sustained progression-free survival benefit in patients (pts) with newly diagnosed advanced ovarian cancer after first-line treatment in the phase 3 ATHENA-MONO study (NCT03522246). We report final safety analyses (data cutoff 09 Mar 2023). Methods: Rucaparib was administered in 28-day cycles. Eligible pts were randomized 4:1 to oral rucaparib 600 mg BID (N=427) or placebo (N=111), with a treatment cap defined as 24 months. The safety population included randomized pts who received at least 1 dose of study drug (rucaparib, n=425; placebo, n=110). Results: All ATHENA-MONO pts discontinued treatment as of 24 Nov 2022 with a median treatment duration of 15 months and 35% of pts reaching the 24-month treatment cap. The median (range) relative dose intensity was 89% (30-110) for rucaparib. The rate of treatment-emergent adverse events (TEAEs), grade ≥3 TEAEs, TEAEs leading to interruption, dose reduction, or discontinuation with rucaparib remained consistent with the primary endpoint analysis with some minor changes (see Table below). Most common grade ≥3 TEAEs were anemia/decreased hemoglobin (28.7%), neutropenia/decreased neutrophils (14.6%), increased ALT/AST (10.6%), and thrombocytopenia/decreased platelets (7.3%). The most common TEAEs leading to discontinuation were anemia/decreased hemoglobin (3.5%), asthenia/fatigue (4.9%), and nausea (2.1%). Hypertension continued to be the most common TEAE observed in the placebo group (3.6%) compared with 1.6% in the rucaparib group. There were no changes in the incidence of serious adverse events or TEAEs leading to death since the primary endpoint analysis. Myelodysplastic syndromes (MDS)/acute myeloid leukemia (AML) were reported in a total of 3 pts in the rucaparib group (1 MDS during treatment [0.2%] and 1 AML and 1 MDS during long-term follow-up [0.5%]), of which the latter occurred since the primary readout. The initial MDS event that occurred during treatment, included in these incidence numbers, was considered resolved by the investigator since the initial analysis. Conclusions: Long-term maintenance treatment with rucaparib demonstrates a consistent and manageable safety profile in a broad population of pts with newly diagnosed ovarian cancer. No new safety signals were identified. Adverse events were generally manageable and led to discontinuation in a low proportion of pts. Clinical trial information: NCT03522246 . [Table: see text]

Ivonescimab Plus Chemotherapy in Non–Small Cell Lung Cancer With EGFR Variant

For patients with non-small cell lung cancer whose disease progressed while receiving EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy, particularly third-generation TKIs, optimal treatment options remain limited. To compare the efficacy of ivonescimab plus chemotherapy with chemotherapy alone for patients with relapsed advanced or metastatic non-small cell lung cancer with the epidermal growth factor receptor (EGFR) variant. Double-blind, placebo-controlled, randomized, phase 3 trial at 55 sites in China enrolled participants from January 2022 to November 2022; a total of 322 eligible patients were enrolled. Participants received ivonescimab (n = 161) or placebo (n = 161) plus pemetrexed and carboplatin once every 3 weeks for 4 cycles, followed by maintenance therapy of ivonescimab plus pemetrexed or placebo plus pemetrexed. The primary end point was progression-free survival in the intention-to-treat population assessed by an independent radiographic review committee (IRRC) per Response Evaluation Criteria in Solid Tumors version 1.1. The results of the first planned interim analysis are reported. Among 322 enrolled patients in the ivonescimab and placebo groups, the median age was 59.6 vs 59.4 years and 52.2% vs 50.9% of patients were female. As of March 10, 2023, median follow-up time was 7.89 months. Median progression-free survival was 7.1 (95% CI, 5.9-8.7) months in the ivonescimab group vs 4.8 (95% CI, 4.2-5.6) months for placebo (difference, 2.3 months; hazard ratio [HR], 0.46 [95% CI, 0.34-0.62]; P < .001). The prespecified subgroup analysis showed progression-free survival benefit favoring patients receiving ivonescimab over placebo across almost all subgroups, including patients whose disease progressed while receiving third-generation EGFR-TKI therapy (HR, 0.48 [95% CI 0.35-0.66]) and those with brain metastases (HR, 0.40 [95% CI, 0.22-0.73]). The objective response rate was 50.6% (95% CI, 42.6%-58.6%) with ivonescimab and 35.4% (95% CI, 28.0%-43.3%) with placebo (difference, 15.6% [95% CI, 5.3%-26.0%]; P = .006). The median overall survival data were not mature; at data cutoff, 69 patients (21.4%) had died. Grade 3 or higher treatment-emergent adverse events occurred in 99 patients (61.5%) in the ivonescimab group vs 79 patients (49.1%) in the placebo group, the most common of which were chemotherapy-related. Grade 3 or higher immune-related adverse events occurred in 10 patients (6.2%) in the ivonescimab group vs 4 (2.5%) in the placebo group. Grade 3 or higher vascular endothelial growth factor-related adverse events occurred in 5 patients (3.1%) in the ivonescimab group vs 4 (2.5%) in the placebo group. Ivonescimab plus chemotherapy significantly improved progression-free survival with tolerable safety profile in TKI-treated non-small cell lung cancer. ClinicalTrials.gov Identifier: NCT05184712.

Efficacy and safety of anti-angiogenic drug monotherapy and combination therapy for ovarian cancer: a meta-analysis and trial sequential analysis of randomized controlled trials.

As the development of novel anti-angiogenic drugs and the continuous evolution of guideline recommendations, the efficacy and safety of anti-angiogenic agents in ovarian cancer (OC) remains unclear. Consequently, a meta-analysis was carried out to assess the efficacy and safety of anti-angiogenic drug monotherapy and combination therapy for OC. An exhaustive literature review was performed across multiple databases, including PubMed, Embase, Web of Science, and Cochrane, encompassing all relevant randomized controlled trials (RCTs) up until 6 April 2024. The evaluation of efficacy outcomes incorporated progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). Safety was assessed through the occurrence of any grade adverse events (AEs) and grade ≥3 AEs. Synthesis of the data involved the calculation of hazard ratios (HRs), relative risks (RRs), and their corresponding 95% confidence intervals (CIs) and prediction intervals (PIs). Trial sequential analysis was executed employing TSA v0.9.5.10 Beta software, STATA 12.0, and R software 4.3.1. In this meta-analysis, 35 RCTs were included, encompassing 16,199 subjects in total. The overall analysis indicated that anti-angiogenic drug combination therapy significantly improved PFS (HR [95% CI] = 0.678 [0.606-0.759], 95% PI: 0.415-1.108), OS (HR [95% CI] = 0.917 [0.870-0.966], 95% PI: 0.851-0.984), and ORR (RR [95% CI] = 1.441 [1.287-1.614], 95% PI: 1.032-2.014), but also increased the incidence of grade ≥3 AEs (RR [95% CI] = 1.137 [1.099-1.177], 95% PI: 1.011-1.252). The analysis did not corroborate any benefit of anti-angiogenic monotherapy over placebo concerning PFS (HR [95% CI] = 0.956 [0.709-1.288], 95% PI: 0.345-2.645) and OS (HR [95% CI] = 1.039 [0.921-1.173], 95% PI: 0.824-1.331). However, it was observed that monotherapy with anti-angiogenic drugs did increase the incidence of any grade AEs (RR [95% CI] = 1.072 [1.036-1.109], 95% PI: 0.709-1.592). Our study confirmed the PFS, OS, and ORR benefits of anti-angiogenic drug combination therapy for OC patients. The efficacy results of anti-angiogenic monotherapy necessitates further evaluation as more RCTs become available. Clinicians should be vigilant of AEs when administering anti-angiogenic agents in a clinical setting.

Factors associated with the efficacy of first-line nivolumab plus chemotherapy in advanced gastric cancer patients with deficient mismatch repair.

We aimed to investigate clinicopathologic factors leading to different clinical outcomes in patients with deficient mismatch repair protein (d-MMR) gastric cancer (GC) treated with nivolumab plus chemotherapy (nivolumab chemotherapy). This retrospective study included 28 patients with d-MMR advanced GC treated with first-line nivolumab chemotherapy. As a control group, 68 treated with first-line chemotherapy alone were included. Clinicopathological factors, including the neutrophil-to-lymphocyte ratio (NLR) and PD-L1 combined positive score (CPS), were analyzed with regards to the efficacy outcomes. Progression-free survival (PFS) was longer (median PFS; not reached [NR] vs. 5.2months, hazard ratio [HR] 0.28, P < 0.001), and overall survival (OS) tended to be longer (median OS; NR vs. 17.9months, HR 0.43, P = 0.057) in patients treated with nivolumab chemotherapy than those treated with chemotherapy. The PFS benefit of nivolumab chemotherapy over chemotherapy was pronounced in the subgroup with a lower NLR (< 3.80 [median NLR]) (HR 0.10), whereas it was less prominent in patients with a high NLR (≥ 3.80) (HR 0.58). Among patients treated with nivolumab chemotherapy, PFS was worse in patients with a higher NLR (≥ 3.80) than in those with a lower NLR (< 3.80), and survival outcomes were similar between those with PD-L1 CPS ≥ 5 and < 5. Nivolumab chemotherapy was associated with better efficacy outcomes than chemotherapy alone among patients with d-MMR GC, but survival outcomes were poor even with nivolumab chemotherapy for those with a high NLR. Survival outcomes were not different according to PD-L1 CPS among d-MMR patients treated with nivolumab chemotherapy.

Final Results of RIGHT Choice: Ribociclib Plus Endocrine Therapy Versus Combination Chemotherapy in Premenopausal Women With Clinically Aggressive Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer.

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). In this open-label, multicenter, randomized phase II trial, pre/perimenopausal women with clinically aggressive HR+/HER2- ABC were randomly assigned 1:1 to first-line ribociclib (600 mg once 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 end point was progression-free survival (PFS). Among 222 patients randomly assigned 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 nonvisceral disease. Overall, 106 (47.7%) patients had investigator-assessed visceral crisis. The 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 to 26.7]) and 12.8 months (combination CT; [95% CI, 10.1 to 18.4); hazard ratio, 0.61 [95% CI, 0.43 to 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 (hazard ratio, 0.76 [95% CI, 0.55 to 1.06]). Lower rates of symptomatic adverse events were observed in the ribociclib versus CT arm. 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.