Central Nervous System Objective Response Research Articles

Neratinib and ado-trastuzumab emtansine for pretreated and untreated human epidermal growth factor receptor 2 (HER2)-positive breast cancer brain metastases: Translational Breast Cancer Research Consortium trial 022

Treatment options for human epidermal growth factor receptor 2 (HER2)-positive breast cancer brain metastases (BCBMs) remain limited. We previously reported central nervous system (CNS) activity for neratinib and neratinib-capecitabine. Preclinical data suggest that neratinib may overcome resistance to ado-trastuzumab emtansine (T-DM1) when given in combination. In Translational Breast Cancer Research Consortium (TBCRC) 022's cohort 4, we examined the efficacy of neratinib plus T-DM1 in patients with HER2-positive BCBM. In this multicenter, phase II study, patients with measurable HER2-positive BCBM received neratinib 160 mg daily plus T-DM1 3.6 mg/kg intravenously every 21 days in three parallel-enrolling cohorts [cohort 4A-previously untreated BCBM, cohorts 4B and 4C-BCBM progressing after local CNS-directed therapy without (4B) and with (4C) prior exposure to T-DM1]. Cycle 1 diarrheal prophylaxis was required. The primary endpoint was the Response Assessment in Neuro-Oncology-Brain Metastases (RANO-BM) by cohort. The overall survival (OS) and toxicity were also assessed. Between 2018 and 2021, 6, 17, and 21 patients enrolled in cohorts 4A, 4B, and 4C. Enrollment was stopped prematurely for slow accrual. The CNS objective response rate in cohorts 4A, 4B, and 4C was 33.3% [95% confidence interval (CI) 4.3% to 77.7%], 35.3% (95% CI 14.2% to 61.7%), and 28.6% (95% CI 11.3% to 52.2%), respectively; 38.1%-50% experienced stable disease for ≥6 months or response. Diarrhea was the most common grade 3 toxicity (22.7%). The median OS was 30.2 [cohort 4A; 95% CI 21.9-not reached (NR)], 23.3 (cohort 4B; 95% CI 17.6-NR), and 20.9 (cohort 4C; 95% CI 14.9-NR) months. We observed intracranial activity for neratinib plus T-DM1, including those with prior T-DM1 exposure, suggesting synergistic effects with neratinib. Our data provide additional evidence for neratinib-based combinations in patients with HER2-positive BCBM, even those who are heavily pretreated.

Utidelone plus bevacizumab for the treatment of HER2-negative breast cancer brain metastases (U-BOMB): A multicenter, single-arm phase II study.

1081 Background: The primary treatment for brain metastases in patients with HER2-negative advanced breast cancer is predominantly local therapies like radiotherapy, owing to the limited efficacy of systemic therapies. Prior research has demonstrated utidelone's significant permeability across the blood-brain barrier and the preliminary effectiveness of bevacizumab for breast cancer brain metastases. Consequently, this study investigated the efficacy and safety of utidelone combined with bevacizumab in the treatment of advanced breast cancer brain metastases. Methods: This study was a single-arm, multi-center phase II clinical trial (NCT05357417). Eligible patients were aged 18 years or older with either radiotherapy-naive or progressive brain metastases post-radiotherapy, presented with asymptomatic or symptomatic brain metastases associated with HER2-negative breast cancer.Patients received intravenous bevacizumab (15 mg/kg on day 1 of each 3-week cycle) and utidelone (30 mg/m2 on days 1 to 5 of each cycle) until intolerance or disease progression. The primary endpoint was central nervous system objective response rate (CNS-ORR), as assessed according to the Response Evaluation Criteria In Solid Tumors version 1.1. Results: Between May 5, 2022, and October 25, 2023, a total of 46 patients were recruited, with a median age of 52.5 years (range, 33 to 69). Among them, 35 patients had untreated CNS lesions, while 11 had progressive brain metastases after local radiotherapy. The CNS-ORR was 43.5% (95% confidence interval [CI], 28.9%-58.9%). As of January 8, 2024, the median duration of follow-up was 14.6 months, and the median progression-free survival (PFS) was 7.7 months (95% CI: 5.5-10.8) as shown in Table. The 12-month overall survival (OS) rate reached 74.4% (95% CI: 60.0%-92.3%). The most common grade 1-2 adverse events (AEs) were peripheral neuropathy (87.5%), decreased neutrophil count (62.5%), anemia (47.5%), diarrhea (37.5%), and increased alanine aminotransferase (25%). No grade 3 or higher treatment-related AEs occurred. Conclusions: This study preliminarily shows promising efficacy and manageable safety of the combination of utidelone and bevacizumab in the treatment of HER2-negative metastatic breast cancer patients with brain metastases. Clinical trial information: NCT05357417 . [Table: see text]

Tyrosine kinase inhibitors with and without upfront CNS radiation for brain metastases in oncogene-driven non-small cell lung cancer (TURBO-NSCLC).

2019 Background: Newer generation tyrosine kinase inhibitors (TKI) for NSCLC with EGFR mutations and ALK rearrangements have demonstrated encouraging central nervous system (CNS) activity with CNS objective response rates, greatly improved from 1st generation TKIs. In response to these data, guideline statements have acknowledged a strategy of CNS-penetrant TKI +/- upfront stereotactic radiosurgery (SRS) for the treatment of select patients with BM. However, optimal use of upfront SRS for BM in these patients is controversial since upfront CNS radiation has been the historical standard of care, and there are limited data guiding patient management with upfront TKI alone. Additionally, results from a large multi-institutional series reported inferior overall survival (OS) with the omission of SRS in patients with EGFR-mutated NSCLC treated with first-generation TKI. Methods: Data on TKI-naïve patients with EGFR- and ALK-driven NSCLC with BM treated with CNS-penetrant TKIs +/- upfront SRS were retrospectively collected from 7 centers in the United States. Time to CNS progression (PD), local CNS PD, and OS were analyzed, with multivariable adjustment (MVA) in Fine and Gray and Cox proportional hazards models for baseline factors including age, sex, performance status, mutation, extracranial metastases, prior therapy, neurologic symptoms, and number and size of BM. Results: We identified 317 patients (200 TKI only and 117 TKI+SRS). 250 (79%) and 61 (19%) patients received osimertinib and alectinib, respectively. Patients who received TKI+SRS were more likely to have BM ≥1 cm (p<0.001) and neurologic symptoms (p<0.001) at baseline. The median follow-up from treatment of BM was 23 months and 26 months in the TKI and TKI+SRS groups, respectively. Median OS was similar between the TKI and TKI+SRS groups (median 41 months [95% CI: 35-NR] vs 40 months [95% CI: 40-NR], respectively; p=0.5). On MVA, TKI+SRS was associated with a significant improvement in time to CNS PD (HR 0.63; 95% CI: 0.42-0.96; p=0.033). Local CNS control was significantly improved with TKI+SRS (HR 0.30, 95% CI: 0.16-0.55; p<0.001), whereas no significant differences were observed in distant CNS control. Subgroup analyses demonstrated greater CNS control benefits with TKI+SRS in patients with BM ≥1 cm. Conclusions: This is the largest multi-institutional study comparing strategies of CNS-penetrant TKIs +/- upfront SRS in TKI-naïve patients with oncogene-driven NSCLC. The addition of SRS improved time to CNS PD and local CNS control but not OS. Patients with BM ≥1 cm may benefit the most from upfront integration of SRS. [Table: see text]

Brain Radiotherapy With Pyrotinib and Capecitabine in Patients With ERBB2-Positive Advanced Breast Cancer and Brain Metastases

The potential benefit of combining intracranial effective systemic therapy with radiotherapy for patients with breast cancer with brain metastases remains unclear. To assess the activity and safety of combining radiotherapy with pyrotinib and capecitabine in patients with ERBB2-positive breast cancer and brain metastases. This was a single-arm, single-center, phase 2 nonrandomized clinical trial with a safety run-in phase. Between January 2020 and August 2022, patients with ERBB2-positive breast cancer and brain metastases were enrolled. The data cutoff date was February 1, 2023. Patients received either fractionated stereotactic radiotherapy or whole-brain radiotherapy. Treatment with pyrotinib (400 mg, once daily) and capecitabine (1000 mg/m2, twice daily, on days 1-14 of each 21-day cycle) was initiated from the first day of radiotherapy to the seventh day after the completion of radiotherapy and continued until disease progression or unacceptable toxic effects. The primary end point was 1-year central nervous system (CNS) progression-free survival (PFS) rate. Secondary end points included CNS objective response rate (ORR), PFS, overall survival (OS), safety, and changes in neurocognitive function. A total of 40 female patients (median age, 50.5 years [IQR, 46-59 years]) were enrolled and received treatment, including 3 patients in safety run-in phase. With a median follow-up of 17.3 months (IQR, 10.3-26.9), the 1-year CNS PFS rate was 74.9% (95% CI, 61.9%-90.7%), and the median CNS PFS was 18.0 months (95% CI, 15.5 to not reached). The 1-year PFS rate was 66.9% (95% CI, 53.1%-84.2%), and the median PFS was 17.6 months (95% CI, 12.8-34.1). The CNS objective response rate was 85% (34 of 40). Median overall survival was not reached. The most common grade 3 or 4 treatment-related adverse event was diarrhea (7.5%). Asymptomatic radiation necrosis was identified in 4 of 67 lesions (6.0%) treated with fractionated stereotactic radiotherapy. Most patients maintained neurocognitive function, as evaluated by the Mini-Mental State Examination at different points. The results of this trial suggest that radiotherapy combined with pyrotinib and capecitabine is associated with long intracranial survival benefit in patients with ERBB2-positive advanced breast cancer and brain metastases with an acceptable safety profile. This combination deserves further validation. ClinicalTrials.gov Identifier: NCT04582968.

Pertuzumab plus high-dose trastuzumab for HER2-positive breast cancer with brain metastases: PATRICIA final efficacy data

The PATRICIA study (NCT02536339) examined the efficacy and safety of pertuzumab plus high-dose trastuzumab in patients with HER2-positive metastatic breast cancer (MBC) with progressive central nervous system (CNS) metastases following radiotherapy. Primary analysis confirmed CNS objective response rate (ORR) was 11% (95% confidence interval [CI]: 3–25); clinical benefit rate (CBR) was 68% (4 months) and 51% (6 months). We report final efficacy data after a further 21-months of follow-up, updated safety, survival, and patient-reported outcomes (PROs). Patients received standard-dose pertuzumab plus high-dose trastuzumab (6 mg/kg weekly) until CNS or systemic disease progression or unacceptable toxicity. Primary endpoint: confirmed ORR (CNS) per Response Assessment in Neuro-Oncology Brain Metastases criteria. Secondary endpoints were response duration, CBR, progression-free survival (PFS), overall survival (OS), safety, and PROs. By clinical cut-off, 39 patients had completed or discontinued treatment. Confirmed ORR (CNS) was 11% (95% CI: 3.0–25.4). Median CNS-PFS was 4.6 months (95% CI: 4.0–8.9), as was median CNS-PFS or systemic PFS (95% CI: 4.0–8.9); median OS was 27.2 months (95% CI: 16.1–not reached). CBR in the CNS was 51% (19 patients, 95% CI: 34.4–68.1) at 6 months. Two patients remained on treatment until study closure, achieving stable disease for 4.1 and 4.8 years. Treatment-related grade 3/4 adverse events occurred in 7.7% of patients. Patients with confirmed partial response or stable disease (≥4 months) in the CNS had stable PROs over time. Pertuzumab plus high-dose trastuzumab represents a reasonable non-chemotherapeutic treatment option for selected patients with HER2-positive MBC with CNS metastases.

Radiotherapy combined with pyrotinib plus capecitabine in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer and brain metastases: A single-arm, exploratory trial.

e13024 Background: Previous researches indicated the enhanced radiosensitivity in HER2-positive cancer cells by pyrotinib. For patients with treatment-naive brain metastases and central nervous system (CNS) symptoms, whether radiotherapy (current mainstay treatment) combined with pyrotinib-based systemic regimen is more beneficial remains unclear. This study explored radiotherapy combined with pyrotinib plus capecitabine in this population. Methods: In this exploratory trial (NCT04767828), patients aged 18-75 years who had HER2-positive metastatic breast cancer and untreated symptomatic brain metastases with an Eastern Cooperative Oncology Group performance status of 0-2 were included. Patients with meningeal metastases or without measurable CNS lesions were excluded. Eligible patients received whole-brain radiotherapy (WBRT) or stereotactic radiotherapy (SRT). The irradiation sites, total radiation dose, and fractions were decided by investigator based on the number of CNS lesions and size. Pyrotinib (400 mg, once a day) and capecitabine (1000 mg/m2, twice a day, on days 1-14 of each 21-day cycle) were given since the start of radiotherapy until disease progression or intolerable toxicity. The primary endpoint was CNS progression-free survival (PFS), assessed by Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM). Extracranial lesions were assessed by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Results: Between May 5, 2020 and November 25, 2022, a total of 19 patients were enrolled. Thirteen (68%) patients had other visceral metastases, and 18 (95%) had prior trastuzumab treatment (5 for early breast cancer, 12 for advanced breast cancer, and 1 for both). Fifteen (79%) patients received WBRT and 4 (21%) received SRT. By the data cutoff date on January 16, 2023, the median follow-up duration was 15.0 months (range, 1.7-24.8). Median CNS PFS was 10.0 months (95% CI, 5.3-14.7). CNS objective response rate was 100%, including two (11%) patients with CNS complete response. Median overall PFS was 8.5 months (95% CI, 4.8-12.2). Median overall survival was 19.0 months (95% CI, 13.1-24.9). The most common grade 3 or 4 adverse events were vomiting (16%) and nausea (11%). For 11 patients with available results of Mini-Mental State Examination (MMSE), 10 (91%) had normal cognitive function during study period or recovered to normal level within 6 months after radiotherapy. Conclusions: Radiotherapy combined with pyrotinib plus capecitabine shows favorable CNS response and promising survival outcomes in patients with HER2-positive metastatic breast cancer and untreated symptomatic brain metastases, with an acceptable safety profile. This combination strategy warrants further validation in large samples. Clinical trial information: NCT04767828 .

Efficacy and safety of dose-escalated alectinib in patients with metastatic ALK-positive NSCLC and CNS relapse on standard dose alectinib.

e21079 Background: Central nervous system (CNS) metastases represent a common cause of morbidity and mortality in patients (pts) with ALK-positive (ALK+) non-small cell lung cancer (NSCLC), with limited therapeutic options. We previously reported re-induction of CNS responses using dose intensification of alectinib in two pts with metastatic ALK+ NSCLC who had experienced CNS progression on standard dose alectinib. However, this strategy has not been assessed in larger cohorts. Methods: In this retrospective study, pts were eligible if they had advanced ALK+ NSCLC with CNS relapse on standard dose alectinib (600 mg twice daily) and subsequently received dose-escalated alectinib (900 mg twice daily). Medical records and radiographic imaging were reviewed to determine treatment outcomes. CNS efficacy was assessed per the modified Response Evaluation Criteria in Solid Tumors version 1.1. Treatment-related adverse events (trAEs) were graded per the CTCAE version 5.0. Results: 27 pts were eligible [male, 67%; median age at diagnosis, 53 (range, 31-69)]. Pts had previously received median 3 lines of systemic therapy (range, 1-12) and median 2 ALK TKIs (range, 1-4); all had received standard dose alectinib with CNS progression. 19 pts (70%) had received prior CNS-directed radiotherapy (RT) [median time from most recent RT to dose-escalated alectinib, 13.9 months (mos) (range, 0.2-52.3)]. The median duration of dose-escalated alectinib therapy in this cohort was 7.7 mos (95% CI, 4.8-10.9), with median overall progression-free survival (PFS) of 7.8 mos (95% CI, 4.9-13.7). Among 25 response-evaluable pts with baseline measurable or non-measurable CNS metastases, the CNS objective response rate (ORR) was 8.0% (95% CI, 1.0-26.0), with 2 pts having intracranial complete responses. CNS disease control rate (DCR) was 92.0% (95% CI, 74.0-99.0), with median CNS duration of response (DoR) of 5.3 mos (95% CI, 3.4-8.3) and median CNS PFS of 7.1 mos (95% CI, 4.4-13.7). Of 3 patients with baseline measurable CNS disease, all 3 had best intracranial response of SD, and median CNS PFS was 6.7 mos (95% CI, 6.2-not reached). Dose-escalated alectinib was well tolerated with no drug discontinuation due to trAE and no grade 3 or higher trAEs. One pt required dose reduction to 750 mg twice daily due to intolerable grade 2 fatigue. 23 pts (85%) experienced grade 1-2 trAEs. Grade 1-2 trAEs that occurred in 10% of pts were anemia (52%), fatigue (37%), constipation (26%), bilirubin increase (15%), alkaline phosphatase increase (15%), and peripheral neuropathy (11%). Conclusions: Dose intensification of alectinib demonstrated meaningful efficacy and tolerability in pts with metastatic ALK+ NSCLC who had experienced CNS disease relapse on standard dose alectinib, and may represent a viable therapeutic option for re-establishing CNS disease control.

Safety and efficacy of osimertinib plus bevacizumab as first-line treatment in EGFR-mutated NSCLC with brain metastasis instructed by dynamic monitoring circulating tumor DNA of paired cerebrospinal fluid and plasma.

e21182 Background: The management of brain metastases in lung cancer was always a global challenge. Studies have shown that erlotinib combined with bevacizumab could bring progression-free survival benefit for NSCLC. Osimertinib is a third-generation EGFR tyrosine kinase inhibitor with higher CNS penetration. This study was to evaluate the safety and efficacy of osimertinib plus bevacizumab as the first-line treatment for patients with EGFR-positive NSCLC and brain metatases, and reveal the molecular characteristics of intracranial progression by matching plasma and CSF ctDNA. Methods: Patients with EGFR-positive NSCLC and brain metatases were treated with osimertinib (80mg, daily) plus bevacizumab (5mg/kg, every 4 week) as the first-line treatment. CSF and paird plasma ctDNA were collected before osimertinib and at the time of disease stable, intracranial progression and systematic progression, using the next-generation sequencing (NGS) to explore the dynamic changes between them. The primary end point was median CNS progression-free survival (PFS), CNS objective response rate (ORR). The second end point was to explore the molecular mechanism of CNS progression. Results: As the time of data cutoff (Jan 31, 2023), 15 patients were enrolled. 3 patients (20%) progressed in lung, 2 patients (13.3%) progressed in brain, and 1 patient (6.7%) progressed in leptomeningeal and bone, 2 of them still received oral osimertinib (80mg, daily). 9 patients (60%) were in partial or complete reponse and 8 of them continued to receive the original treatment. The median osimertinib exposure time was 16.8 months. The median bevacizumab exposure time was 9.1 months. The median CNS progression-free survival was 15.5 months (6.8 months to not reached). The CNS objective response rate was 93.33%. Six patients received gamma knife radiotherapy before Osimertinib, the median CNS progression-free survival was 14 months (6.8 months to not reached), the CNS objective response rate was 100%. After progression on Osimertinib, paired CSF and plasma ctDNA were analyzed and EGFR C797S, TP53, CDKN2A and etc could be found as resistanct mechanism. Adverse events of grade 3 or worse were observed in 1 patients (6.7%): severe ulcerative colitis, leading to the suspension of osimertinib. 2 patients (13.3%) stopped bevacizumab because of bleeding. Conclusions: This is a mid-term report with immature data. By the end of follow-up, we expected that osimertinib plus bevacizumab could better reduce the risk of intracranial progression and prolong the progression-free survival compared with osimertinib monotherapy. Clinical trial information: KY2021-155-02.

Central nervous system efficacy of furmonertinib (AST2818) in patients with EGFR T790M mutated non-small cell lung cancer: a pooled analysis from two phase 2 studies

BackgroundFurmonertinib (AST2818) is a brain penetrant pan-epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) targeting both EGFR sensitizing mutations and T790M mutation. We report the pooled central nervous system (CNS) efficacy data of furmonertinib in patients with EGFR T790M mutated non-small cell lung cancer (NSCLC) from two phase 2 studies.MethodsThis was a pooled, post-hoc analysis of two phase 2 studies (NCT03127449 [phase 2a study of furmonertinib], NCT03452592 [phase 2b study of furmonertinib]). In the phase 2a study, patients received furmonertinib 40 mg, 80 mg, 160 mg, or 240 mg orally once daily. In the phase 2b study, all patients received furmonertinib 80 mg orally once daily. CNS efficacy of furmonertinib was analyzed in patients with baseline CNS lesions by an independent review center per Response Evaluation Criteria in Solid Tumors version 1.1.ResultsA total of 132 patients with baseline CNS metastases were included in this analysis. In 52 patients with measurable CNS lesions, CNS objective response rates were zero (0/1), 65% (22/34), 85% (11/13), and 25% (1/4), and CNS disease control rates were zero (0/1), 97% (33/34), 100% (13/13), and 100% (4/4) in the 40 mg, 80 mg, 160 mg, and 240 mg orally once daily group, respectively. In patients with measurable or non-measurable CNS lesions, median CNS progression-free survival was 2.8 months (95% confidence interval [CI] 1.4–8.3), 11.6 months (95% CI 8.3–13.8), 19.3 months (95% CI 5.5-not available [NA]), and not reached (95% CI 2.8 months-NA) in the 40 mg, 80 mg, 160 mg, and 240 mg orally once daily group, respectively.ConclusionsFurmonertinib showed promising CNS efficacy in doses of 80 mg orally once daily or higher in patients with EGFR T790M mutated NSCLC.Trial registrationBoth studies were registered on ClinicalTrial.gov. The phase 2a study was registered with NCT03127449 on April 25, 2017; The phase 2b study was registered with NCT03452592 on March 2, 2018.

Central nervous system efficacy of rezivertinib (BPI-7711) in advanced NSCLC patients with EGFR T790M mutation: A pooled analysis of two clinical studies

BackgroundRezivertinib (BPI-7711) is a novel third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) which revealed the systematic and central nervous system (CNS) antitumor activities for EGFR T790M-mutated advanced NSCLC in previous clinical studies and is further analyzed here. MethodsEligible patients from the previous phase I and phase IIb studies of rezivertinib were included for pooled analysis. Post-progressive patients who received a prescribed dosage (≥180 mg) of rezivertinib orally once daily were included in full analysis set (FAS), while those with stable, asymptomatic CNS lesions, including measurable and non-measurable ones at baseline were included in CNS full analysis set (cFAS). Patients with measurable CNS lesions were included in CNS evaluable for response set (cEFR). BICR-assessed CNS objective response rate (CNS-ORR), CNS disease control rate (CNS-DCR), CNS duration of response (CNS-DoR), CNS progression-free survival (CNS-PFS), and CNS depth of response (CNS-DepOR) were evaluated. Results355 patients were included in FAS, among whom 150 and 45 patients were included in cFAS and cEFR. This pooled analysis showed the CNS-ORR was 32.0% (48/150; 95% CI: 24.6–40.1%) and the CNS-DCR was 42.0% (63/150; 95% CI: 34.0–50.3%) in cFAS, while that in cEFR were 68.9% (31/45; 95% CI: 53.4–81.8%) and 100% (45/45; 95% CI: 92.1–100.0%). In cEFR, the median CNS-DepOR and the mean of CNS-DepOR were -52.0% (range: -100.0 to 16.1%) and -46.8% (95% CI: –55.5 to -38.1%). In cFAS, the median CNS-DoR and CNS-PFS were 13.8 (95% CI: 9.6-not calculable [NC]) and 16.5 (95% CI: 13.7-NC) months. ConclusionsRezivertinib demonstrated encouraging clinical CNS efficacy among advanced NSCLC patients with EGFR T790M mutation and CNS metastases.

Abstract PD7-03: Translational Breast Cancer Research Consortium Trial 022: Neratinib and Trastuzumab-Emtansine for HER2+ Breast Cancer Brain Metastases (BCBM)

Abstract PURPOSE: Treatment options for patients (pts) with HER2+ BCBM remain limited. We previously reported that neratinib monotherapy is associated with a volumetric central nervous system objective response rate (CNS ORR) of 8%, whereas the combination of neratinib and capecitabine resulted in a volumetric CNS ORR of 49% (in lapatinib-naïve pts). Preclinical data suggest that neratinib may overcome resistance to trastuzumab-emtansine (T-DM1) and that the combination has potential CNS efficacy. Here, we report results of neratinib plus T-DM1 in pts with HER2+ BCBM. PATIENTS AND METHODS: In this prospective, multicenter, phase II study, pts with measurable HER2+ BCBM received neratinib 160 mg orally once daily plus T-DM1 3.6 mg/kg IV every 21 days in three parallel-enrolling cohorts. Cohort 4A enrolled pts with previously untreated brain metastases. Cohort 4B enrolled pts with BCBM progressing after prior local CNS-directed therapy without prior exposure to T-DM1. Cohort 4C enrolled pts with BCBM progressing after prior local CNS-directed therapy who had previous exposure to T-DM1. Diarrhea prophylaxis with colestipol and loperamide was required during cycle 1. Cohorts 4A and 4B were single-stage with a planned enrollment of 20 patients; cohort 4C had a two-stage design, with a requirement for at least 1 of the first 9 pts to achieve a response in order to enroll a total of 24 patients. The primary endpoint was Response Assessment in Neuro-Oncology-Brain Metastases (RANO BM) in each cohort separately. Correlative studies included patient-reported outcomes (PROs) for gastrointestinal toxicity. RESULTS: We enrolled 6, 17, and 21 patients to cohorts 4A, 4B, and 4C, during 11/07/2018 – 11/01/2021. Enrollment was stopped prematurely due to slow accrual. Across Cohorts 4A-4C, the median number of prior lines of chemotherapy prior to enrollment was 2 (range 1-10); 25% received prior lapatinib and no patients received prior tucatinib. In cohorts 4B and 4C (prior CNS-treated cohorts), 33% had prior CNS surgery and >94% had prior CNS radiation. Among evaluable patients, CNS ORR in cohorts 4A (n=6), 4B (n=16), and 4C (n=21) was 50.0% (95% CI 18.8- 81.2%), 25.0% (95% CI 8.3-52.6%), and 38.1% (95% CI 19.0-61.3%), respectively. Median (range) number of cycles completed for 4A, 4B, and 4C was 4.5 (1-15), 4 (range 0-49+), and 6 (0-23); three patients on Cohort 4B remain on protocol therapy (cycles 14, 45, and 49). The overall survival at 12-months for cohorts 4A, 4B, and 4C was 83.3% (95% CI, 58.3-100%), 86.2% (95% CI 70-100%), and 83.3% (95% CI 67.6-100%). Diarrhea was the most common grade 3 toxicity (19.0–33.3% across cohorts); one grade 4 liver function event occurred in cohort 4B. Updated efficacy results will be reported at the meeting; PRO analyses are ongoing. CONCLUSION: Intracranial activity was observed for the combination of neratinib plus T-DM1 across all three enrolled cohorts, including those with prior T-DM1 exposure, suggesting synergistic effects of this treatment combination. Our data provide additional evidence for consideration of neratinib-based combinations in pts with HER2+ BCBM. Citation Format: Rachel Freedman, Siyang Ren, Nabihah Tayob, Rebecca Gelman, Karen L. Smith, Raechel Davis, Alyssa Pereslete, Victoria Attaya, Christine Cotter, Wendy Y. Chen, Cesar Augusto Santa-Maria, Catherine Van Poznak, Beverly Moy, Adam M. Brufsky, Michelle Melisko, Ciara C. O’Sullivan, Nadia Ashai, Yasmeen Rauf, Julie Nangia, Dario Trapani, Jennifer Savoie, Robyn Burns, Antonio C. Wolff, Eric Winer, Mothaffar Rimawi, Ian Krop, Nancy U. Lin. Translational Breast Cancer Research Consortium Trial 022: Neratinib and Trastuzumab-Emtansine for HER2+ Breast Cancer Brain Metastases (BCBM) [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 PD7-03.

Central Nervous System Efficacy of Furmonertinib (AST2818) Versus Gefitinib as First-Line Treatment for EGFR-Mutated NSCLC: Results From the FURLONG Study

IntroductionFurmonertinib (AST2818) is a pan-EGFR tyrosine kinase inhibitor with central nervous system (CNS) antitumor activity. We report the CNS efficacy of furmonertinib compared with gefitinib in untreated EGFR-sensitizing mutation-positive NSCLC from the FURLONG study. MethodsFURLONG was a randomized, double-blind, phase 3 study conducted in 55 hospitals in the People’s Republic of China. Patients 1:1 randomly received furmonertinib 80 mg once daily or gefitinib 250 mg once daily treatment. At screening, all the patients underwent brain imaging examination. Patients with asymptomatic steady CNS metastases at baseline constituted this preplanned CNS subgroup analysis. ResultsA total of 358 patients were enrolled in the FURLONG study. In the 133 (37%) patients who had measurable or nonmeasurable CNS lesions, CNS progression-free survival was 20.8 months (95% confidence interval [CI]: 15.2–25.3) in the furmonertinib group and 9.8 months (95% CI: 7.2–18.0) in the gefitinib group (hazard ratio = 0.40 [95% CI: 0.23–0.71], p = 0.0011). In the 60 patients (17%) who had measurable CNS lesions, CNS objective response rate was 91% (95% CI: 72–99) with furmonertinib and 65% (95% CI: 48–80) with gefitinib (OR = 6.82 [95% CI: 1.23–37.67], p = 0.0277). The least-square mean of CNS depth of response was 62% (95% CI: 51–72) in the furmonertinib group and 39% (95% CI: 30–47) in the gefitinib group, the mean difference was 23% (95% CI: 10–37, p = 0.0011). ConclusionsFurmonertinib first-line treatment was found to have superior efficacy in CNS progression-free survival, CNS objective response rate, and CNS depth of response compared with gefitinib in patients with EGFR-mutated NSCLC with CNS metastases.

Central nervous system efficacy of furmonertinib versus gefitinib in patients with non–small cell lung cancer with epidermal growth factor receptor mutations: Results from FURLONG study.

9101 Background: Furmonertinib (AST2818) is a third-generation epidermal growth factor receptor ( EGFR) tyrosine kinase inhibitor (TKI) with central nervous system (CNS) penetration. Here we report the CNS response to furmonertinib versus gefitinib as first-line therapy in EGFR-mutated non-small cell lung cancer (NSCLC) patients in the FURLONG study. Methods: FURLONG was a randomized, double-blind, multi-center phase III study. Patients were randomized 1:1 to receive first-line furmonertinib 80mg/d or gefitinib 250mg/d. Brain scan was mandatory at screening. Patients with asymptomatic CNS metastases who did not require steroid treatment for 28 days or more were enrolled. A pre-planned CNS efficacy analysis was done using RECIST v1.1 in patients with measurable or non-measurable CNS lesions (cFAS) and patients with only measurable CNS lesions (cEFR). Results: Of 358 enrolled patients in the FURLONG study, 133 (37%) patients were defined as cFAS and 60 (17%) were defined as cEFR according to baseline brain scan judged by a blinded independent review committee (IRC). At the cut-off date of Sep 15, 2021, CNS progression-free survival (PFS) assessed by IRC in the cFAS population was significantly longer in the furmonertinib group than in the gefitinib group (20.8 vs 9.8 months, HR 0.40 [95% 0.23-0.71]; p = 0.0011). CNS PFS rate at 6, 12, 18 months were 91%, 77%, 63% in the furmonertinib group, and 76%, 46%, 34% in the gefitinib group. In the cEFR set, confirmed CNS objective response rate was 91% in patients with furmonertinib and 65% in patients with gefitinib (p = 0.0277), and CNS disease control rate were 100% vs 84% (p = 0.9420), respectively. The mean best percentage change in the sum of target CNS lesion size from baseline in cEFR was -61.8% in the furmonertinib group versus -38.7% in the gefitinib group (p = 0.0011). Conclusions: Furmonertinib showed CNS efficacy as first-line therapy in EGFR-mutated NSCLC patients with CNS lesions. Patients treated with furmonertinib had a reduced risk of CNS progression or death, a higher CNS ORR and a deeper CNS response compared with gefitinib. Clinical trial information: NCT03787992.

Lorlatinib for advanced anaplastic lymphoma kinase–positive non–small cell lung cancer: Results of the IFCT-1803 LORLATU cohort

BackgroundAnaplastic lymphoma kinase (ALK)-rearranged (ALK+) non–small cell lung cancer (NSCLC) represents a rare subset of lung cancer, with specific presentation, and multiple treatment options, including selective tyrosine kinase inhibitors (TKIs). Real-world evidence is insufficient regarding the actual real-life treatment sequences in the late line setting, and available clinical trials may not reflect real-world situation. Here, we took advantage of the French Expanded Access Program (EAP) of lorlatinib, a third-generation TKI targeting ALK and ROS1, to assess treatment sequencing, and lorlatinib efficacy and safety, in patients with ALK+ NSCLC. MethodsAll consecutive patients with advanced ALK+ NSCLC treated between October 2015 and June 2019 with lorlatinib as part of EAP were included. Data were collected and reviewed from medical records by independent research staff of the French Thoracic Cancer Intergroup. The primary endpoint was progression-free survival (PFS). ResultsOf the 208 patients included, 117 (56%) were female, 142 (69%) were never smokers, and 180 (87%) had stage IV NSCLC at diagnosis. The most frequent histology was adenocarcinoma (94%), and the median age was 60.9 years. At the time of lorlatinib initiation, 160 (77%) patients had brain metastases, and 125 (72%) were performance status 0/1. Lorlatinib was delivered as 2nd/3rd/4th/5th+ line in 4%/17%/30%/49% of patients. A total of 162 (78%) patients had previously been treated with chemotherapy, 194 (93%) with a first-generation ALK-TKI, 195 (94%) with a second-generation ALK-TKI. The median follow-up from lorlatinib initiation was 23.3 months. The median PFS, median overall survival (OS) from lorlatinib initiation and median OS from advanced NSCLC diagnosis were 9.9 months (95% confidence interval [CI] 6–12.3 months), 32.9 months (95% CI 18.7 months to not reached) and 97.3 months (95% CI 75.7–152.8 months), respectively. The median duration of treatment with lorlatinib was 11.8 months (95% CI 8.5–18.8 months). Overall response and disease control rate were 49% and 86%, respectively. Central nervous system objective response rate was 56%. Treatment was stopped due to toxicity in 28 patients (14%). The safety profile of lorlatinib was consistent with previously published data. ConclusionsReal-world evidence indicates that lorlatinib offers a significant clinical benefit and high intracerebral antitumour activity in heavily pretreated patients with ALK+ NSCLC. ClinicalTrials.gov identifierNCT03727477.

Assessment of Effectiveness and Safety of Osimertinib for Patients With Intracranial Metastatic Disease

Intracranial metastatic disease (IMD) is a serious and life-altering complication for many patients with cancer. Targeted therapy may address the limitations of current treatments as an additional agent to achieve intracranial disease control in some patients with IMD. Given the paucity of evidence regarding effectiveness, current guidelines have not made recommendations on the use of targeted therapy. Osimertinib mesylate is a mutant epidermal growth factor receptor (EGFR) inhibitor that can penetrate the blood-brain barrier and inhibit tumor cell survival and proliferation in patients with non-small cell lung cancer (NSCLC) with specific EGFR alterations. To assess the effectiveness and safety of osimertinib in the management of IMD. Studies were selected from MEDLINE and Embase databases from their inception to September 20, 2019, using the following search query: (osimertinib OR mereletinib OR tagrisso OR tamarix OR azd9291) AND (brain metastases OR intracranial metastatic disease OR cns). Studies reporting intracranial outcomes for patients with metastatic EGFR-variant NSCLC and IMD treated with osimertinib were included in this systematic review and meta-analysis. Among 271 records identified in the systematic review, 15 studies fulfilled eligibility criteria for inclusion in the meta-analysis. Data were extracted from published studies and supplements. These data were pooled using a random-effects model. Risk of bias was assessed using the Cochrane risk of bias tool and the modified Newcastle-Ottawa Scale. Information extracted included study characteristics, intracranial effectiveness measures, and safety measures. Meta-analyses of proportions were conducted to pool estimates for central nervous system (CNS) objective response rate and CNS disease control rate. Fifteen studies reporting on 324 patients were included in the meta-analysis. The CNS objective response rate was 64% (95% CI, 53%-76%; n = 195), and CNS disease control rate was 90% (95% CI, 85%-93%; n = 246). Included studies reported complete intracranial response rates of 7% to 23%, median best decrease in intracranial lesion size of -40% to -64%, and Common Terminology Criteria for Adverse Events (version 3.0) grade 3 or higher adverse event rates of 19% to 39%. Subgroup analyses did not reveal additional sources of heterogeneity. Findings reported herein support a potential role for osimertinib in the treatment of patients with metastatic EGFR-variant NSCLC and IMD treated with osimertinib. Clinical decision makers would benefit from the inclusion of patients with IMD in future trials to identify factors that predict responses to targeted therapy.

Abstract P2-20-01: Impact of neratinib on development and progression of central nervous system (CNS) metastases in patients with HER2-positive metastatic breast cancer (MBC): Findings from the NALA, NEfERT-T, and TBCRC 022 trials

Abstract Background: The development of metastatic disease in the CNS presents a considerable challenge in the management of patients with MBC as a result of the lack of evidence-based treatment options currently available. Up to 50% of patients with HER2+ MBC develop CNS metastases. A (non-significant) reduction in the cumulative incidence of CNS recurrences was seen in the randomized phase 3 ExteNET trial of neratinib as extended adjuvant treatment of patients with early-stage HER2+ breast cancer following adjuvant trastuzumab-based therapy (Martin et al. Lancet Oncol 2017). Here we review data from the following three trials of neratinib in the metastatic setting: the Phase 3 NALA trial (ClinicalTrials.gov: NCT01808573; Saura et al. ASCO 2019), the Phase 2 NEfERT-T trial (NCT00915018; Awada et al. JAMA Oncol 2016); and the TBCRC 022 trial (NCT01494662; Freedman et al. J Clin Oncol 2019), which suggest activity for neratinib in patients with MBC and CNS metastases. Methods: Patients in NALA (who had received at least 2 lines of HER2-directed therapy for MBC) were randomized 1:1 to neratinib (N; 240 mg qd po) + capecitabine (C; 750 mg/m2 bid po) or lapatinib (L; 1250 mg qd po) + C (1000 mg/m2 bid po). In the NEfERT-T trial, previously untreated patients with recurrent and/or MBC were randomized 1:1 to N (240 mg qd po) or trastuzumab (T; 4 mg/kg then 2 mg/kg weekly), each combined with paclitaxel (P; 80 mg/m2 on days 1, 8, and 15 every 28 days). In TBCRC 022, patients with measurable, progressive HER2+ brain metastases received N (240 mg qd po) + C (750 mg/m2 qd po). The co-primary endpoints in NALA were centrally assessed progression-free survival (PFS) and overall survival (OS); time to intervention for symptomatic metastatic CNS disease was a secondary endpoint. PFS was the primary endpoint in NEfERT-T; frequency of and time to symptomatic and/or progressive CNS lesions was a secondary endpoint. The primary endpoint in TBCRC 022 was composite CNS objective response rate (ORR), requiring a reduction of ≥50% in the sum of target CNS lesion volumes without progression of non-target lesions, new lesions, escalating steroids, progressive neurologic signs or symptoms, or non-CNS progression. Results: CNS outcomes in NALA, NEfERT-T, and TBCRC 022 are summarized in the Table. In NALA, significantly fewer N+C vs L+C-treated patients required intervention for symptomatic CNS metastases. In NEfERT-T, the frequency of symptomatic or progressive CNS recurrences was significantly reduced and the time to onset of CNS progression significantly delayed in the N+P group vs the T+P group. In TBCRC 022, almost half of L-naive patients had a partial response using composite criteria. Table. Overall/CNS outcomes in NALA, NEfERT-T, and TBCRC 022NALANEfERT-TTBCRC 022N+CL+CN+PT+PL-naive N+CL-treated N+CNo. of patients3073142422373712ORR, %332775781443Composite CNS ORR, %aN/AN/AN/AN/A4933CBR, %45*368885N/AN/APFSHR (p-value)0.76 (0.0059)1.02 (0.89)N/AMedian, months8.8b6.6b12.912.95.53.1OSHR (p-value)0.88 (0.2086)1.05 (0.77)N/AMedian, months24.0b22.2bNENE13.315.1Intervention for CNS disease, overall cumulative incidence, %22.8*29.2N/AN/AN/AN/AProgressive CNS disease, cumulative incidence, %c11.213.910.1**20.2N/AN/A*p<0.05 for N+C vs L+C. **p=0.002 for N+P vs T+P. aDefined as a reduction of ≥50% in the sum of target CNS lesion volumes without progression of non-target lesions, new lesions, escalating steroids, progressive neurologic signs or symptoms, or non-CNS progression. bRestricted mean values. cOverall cumulative index in NALA; 2-year cumulative index in NEfERT-T. CBR = clinical benefit rate; N/A = not applicable. NE = not estimable.Conclusions: Neratinib has demonstrated activity against CNS brain metastasis in the setting of advanced and metastatic breast cancer and may also limit the development of new CNS metastases in the adjuvant setting. A pooled analysis of data from NALA and NEfERT-T, which will enable subgroup analyses to be performed, is underway and will be presented at the meeting. Citation Format: Ahmad H Awada, Adam M Brufsky, Cristina Saura, Rachel A Freedman, Nancy U Lin, Judith Bebchuk, Feng Xu, Sara Hurvitz. Impact of neratinib on development and progression of central nervous system (CNS) metastases in patients with HER2-positive metastatic breast cancer (MBC): Findings from the NALA, NEfERT-T, and TBCRC 022 trials [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-20-01.

Phase 2 study of brigatinib in patients (pts) with anaplastic lymphoma kinase (ALK)−positive, advanced non–small cell lung cancer (NSCLC) that progressed on alectinib or ceritinib.

TPS9115 Background: Second-generation ALK tyrosine kinase inhibitors (TKIs) alectinib and ceritinib have demonstrated efficacy and acceptable safety in ALK TKI-pretreated and TKI-naive NSCLC. However, as with crizotinib, resistance to alectinib and ceritinib eventually develops, with secondary resistance mutations detected in approximately 50% of pts. Brigatinib is a next-generation ALK TKI designed to have potent and broad activity against ALK mutants. Post-crizotinib, brigatinib demonstrated high systemic and CNS objective response rates (ORR) and the longest reported median progression-free survival (PFS) of any ALK inhibitor in this setting (16.3–16.7 mo) (Huber. J Clin Oncol 2018;36; Bazhenova. Ann Oncol 2017;28); efficacy was demonstrated regardless of mutations. Based on nonclinical and clinical data, brigatinib may show efficacy in ALK+ NSCLC that has developed resistance or failed to respond to alectinib/ceritinib. This trial was designed to assess efficacy and safety of brigatinib in pts with ALK+ NSCLC that has progressed on alectinib or ceritinib. Methods: This is a phase 2, open-label, single-arm, multicenter, international trial (NCT03535740) in pts (≥18 y) with locally advanced/metastatic NSCLC and disease progression on alectinib or ceritinib (± prior crizotinib; ≤3 different systemic regimens for locally advanced/metastatic disease). Pts receive oral brigatinib 180 mg QD with 7-day lead-in at 90 mg QD. Treatment beyond progression or escalation to brigatinib 240 mg QD is permitted. Primary endpoint: independent review committee (IRC)−assessed confirmed ORR (cORR) per RECIST v1.1. Secondary endpoints: investigator (INV)-assessed cORR, duration of response (INV- and IRC-assessed), PFS, disease control rate, and time to response; in pts with baseline brain metastases: IRC-assessed intracranial cORR, duration of intracranial response, and intracranial PFS; OS; safety/tolerability; and HRQoL. Exploratory endpoints include biomarker analyses. The study was initiated in Dec 2018 at 78 sites (North America, Europe, Asia), with a planned sample size of 103 pts. Accrual is ongoing. Clinical trial information: NCT03535740.

Alectinib versus crizotinib in untreated Asian patients with anaplastic lymphoma kinase-positive non-small-cell lung cancer (ALESIA): a randomised phase 3 study

Anaplastic lymphoma kinase-positive (ALK-positive) disease occurs in approximately 5% of all patients with non-small-cell lung cancer, with a similar incidence reported in Asian patients. This study is the first phase 3 randomised trial recruiting only Asian patients to compare alectinib with crizotinib as a first-line treatment for ALK-positive non-small-cell lung cancer with 600 mg of alectinib twice per day. This study assessed consistency of the progression-free survival benefit with the global phase 3 ALEX study. In this randomised, open-label, phase 3 study done at 21 investigational sites in China, South Korea, and Thailand, Asian patients, aged 18 years or older, with ALK-positive non-small-cell lung cancer were randomly assigned (2:1) to twice-daily oral alectinib (600 mg) or crizotinib (250 mg). Patients were randomly assigned via a block-stratified (block size three) randomisation procedure, done centrally via an interactive voice or web response system, with stratification by Eastern Cooperative Oncology Group performance status and baseline CNS metastases. Clinical staff and the funder's drug safety and medical monitoring staff had access to treatment assignments. The independent review committee was masked to treatment assignment, and funder personnel did not have access to efficacy and safety summaries by treatment group, before the formal reporting of study results. Patients with asymptomatic CNS metastases were permitted. The primary endpoint was investigator-assessed progression-free survival. The primary analysis population for efficacy was the intention-to-treat population, defined as all randomly assigned patients. The primary analysis population for safety was defined as all patients who received at least one dose of study medication. This trial is registered with ClinicalTrials.gov, number NCT02838420. Between Aug 3, 2016, and May 16, 2017, 187 patients were randomly assigned to treatment: 125 to alectinib and 62 to crizotinib. Median follow-up was 16·2 months (IQR 13·7-17·6) in the alectinib group, and 15·0 months (12·5-17·3) in the crizotinib group. Investigator-assessed progression-free survival was significantly prolonged with alectinib versus crizotinib (hazard ratio [HR] 0·22, 95% CI 0·13-0·38; p<0·0001; median progression-free survival not estimable vs 11·1 months). Independent review committee-assessed progression-free survival was also significantly longer in the alectinib group compared with the crizotinib group (HR 0·37, 0·22-0·61; p<0·0001). The proportion of patients who achieved an objective response was 114 (91%) of 125 with alectinib, and 48 (77%) of 62 with crizotinib, with a longer duration of response for alectinib than crizotinib (HR 0·22, 95% CI 0·12-0·40; p<0·0001). Time to CNS progression (cause-specific HR 0·14) and the percentage of patients who achieved a CNS objective response with measurable or non-measurable baseline CNS lesions were improved (32 [73%] of 44 patients treated with alectinib vs five [22%] of 23 patients treated with crizotinib). Despite longer treatment duration with alectinib than crizotinib (14·7 months vs 12·6 months, respectively), fewer patients had grade 3-5 adverse events (36 [29%] of 125 vs 30 [48%] of 62, respectively) or serious adverse events (19 [15%] of 125 vs 16 [26%] of 62, respectively). Our results align with ALEX, confirming the clinical benefit of 600 mg of alectinib twice per day as a first-line treatment for ALK-positive non-small-cell lung cancer. F Hoffmann-La Roche.

Management of CNS metastases in patients with EGFR mutation-positive NSCLC.

Central nervous system (CNS) metastases are a frequent and severe complication associated with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). The first- and second-generation EGFR tyrosine kinase inhibitors (TKIs) have shown considerable efficacy in EGFR-mutated NSCLC. However, their limited potential to cross the blood-brain barrier (BBB) renders them less effective in the management of CNS metastases in NSCLC. Osimertinib, a third-generation irreversible EGFR-TKI with good potential to cross the BBB, has shown significant clinical activity and acceptable safety profile in patients with EGFR-positive NSCLC brain and leptomeningeal metastases. The progression-free survival (PFS) of up to 15.2 months in CNS metastases patients in the FLAURA trial and the CNS objective response rates (ORRs) of 54% and 43% in the AURA/AURA2 and BLOOM trials, respectively, have established the role of osimertinib in patients with NSCLC with CNS metastases. The AURA3 trial also reported a PFS of 8.5 months and overall ORR of 71%. These data have supported osimertinib to be recognized as a "preferred" first-line treatment for EGFR-positive metastatic NSCLC by the National Comprehensive Cancer Network (NCCN). With limited treatment options available, upfront administration of osimertinib in patients with NSCLC irrespective of EGFR T790M and CNS metastases may improve the overall response rate and potentially reduce the adverse effects of radiotherapy. Our review focuses on the management of EGFR-mutated NSCLC CNS metastases in the context of recent NCCN guidelines.

Efficacy of Alectinib in Patients with ALK-Positive NSCLC and Symptomatic or Large CNS Metastases

BackgroundCentral nervous system (CNS) metastases represent a significant source of morbidity and mortality for patients with ALK tyrosine kinase gene (ALK)-positive NSCLC. Alectinib has demonstrated robust CNS activity in both crizotinib-naive and crizotinib-resistant settings. However, the CNS efficacy of alectinib has not been established in patients with untreated symptomatic, large CNS metastases. MethodsIn this retrospective study, patients were eligible if they had advanced ALK-positive NSCLC with large (defined as ≥1 cm) or symptomatic CNS metastases and received alectinib. Medical records and radiographic imaging were reviewed to determine treatment outcomes. CNS efficacy was assessed per the modified Response Evaluation Criteria in Solid Tumors version 1.1. ResultsOf the 19 patients, 15 (79%) had measurable CNS disease at baseline and were evaluable for response. The CNS objective response rate in these patients was 73.3% (95% confidence interval [CI]: 44.9%–92.2%), the CNS disease control rate was 100.0% (95% CI: 78.2%–100.0%), and the median CNS duration of response was 19.3 months (95% CI: 14.3 months–not evaluable). In 18 evaluable patients with measurable and/or nonmeasurable baseline CNS disease, the CNS objective response rate was 72.2% (95% CI: 46.5%–90.3%), the CNS disease control rate was 100.0% (95% CI: 81.5%–100.0%), and the median CNS duration of response was 17.1 months (95% CI: 14.3 months–not evaluable). All eight patients with symptoms attributable to CNS metastases had clinical improvement upon starting alectinib therapy. Six patients (32%) eventually required salvage brain radiotherapy. ConclusionsAlectinib demonstrated meaningful CNS efficacy in patients with ALK-positive NSCLC with untreated symptomatic or large brain metastases.