The Timing, Trajectory, and Incidence of Immune-Related Adverse Events in NSCLC Treated With Atezolizumab

Introduction

Immune-related adverse events (irAEs) due to immune checkpoint inhibitors can have complicated clinical courses. We comprehensively evaluated the timing, trajectory, and incidence of both single and multiple irAEs for NSCLC treated with atezolizumab.

Methods

Data were pooled from 2457 patients who participated in the IMpower130, IMpower132, and IMpower150 clinical trials investigating the use of atezolizumab in metastatic NSCLC as part of a chemoimmunotherapy regimen. Longitudinal irAE data with landmark analysis, time-to-onset, changes in grading severity, and occurrence of multiple events were summarized.

Results

In general, 1557 patients were treated with atezolizumab and 900 patients were in the control groups. Median follow-up was 32.3 and 23.5 months, respectively. In the atezolizumab group, 753 patients (48.4%) experienced at least one irAE. In the control group, 289 patients (32.1%) experienced at least one nonimmune adverse event that was attributed to an irAE. In the atezolizumab group, the most common irAEs were rash, hepatitis, and hypothyroidism. Furthermore, 13% of the patients experienced two irAEs and 4% experienced three irAEs. Within 5 months of treatment, the cumulative incidence for any irAE was 39.2%. Median time-to-onset varied from 1 to 10 months based on the specific irAE. Grade 1 to 2 irAEs increased in severity for 33% of the patients.

Conclusions

We identified dynamic clinical patterns for irAEs in patients treated with atezolizumab, including variations in time-to-onset, incidence of multiple irAEs, and frequency of irAEs increasing in severity. These results can guide clinical management and future reporting of adverse events to enable comprehensive longitudinal analyses.

Neoadjuvant Targeted Therapy in Resectable NSCLC: Current and Future Perspectives

The standard of care (SoC) for medically operable patients with early-stage (stages I-IIIB) NSCLC is surgery combined with (neo)adjuvant systemic therapy for patients with stages II to IIIB disease and some stage IB or, rarely, chemoradiation (stage III disease with mediastinal lymph node metastases). Despite these treatments, metastatic recurrence is common and associated with poor survival, highlighting the need for systemic therapies that are more effective than the current SoC. After the success of targeted therapy (TT) in patients with advanced NSCLC harboring oncogenic drivers, these agents are being investigated for the perioperative (neoadjuvant and adjuvant) treatment of patients with early-stage NSCLC. Adjuvant osimertinib is the only TT approved for use in the early-stage setting, and there are no approved neoadjuvant TTs. We discuss the importance of comprehensive biomarker testing at diagnosis to identify individuals who may benefit from neoadjuvant targeted treatments and review emerging data from neoadjuvant TT trials. We also address the potential challenges for establishing neoadjuvant TTs as SoC in the early-stage setting, including the identification and validation of early response markers to guide care and accelerate drug development, and discuss safety considerations in the perioperative setting. Initial data indicate that neoadjuvant TTs are effective and well tolerated in patients with EGFR- or ALK-positive early-stage NSCLC. Data from ongoing trials will determine whether neoadjuvant targeted agents will become a new SoC for individuals with oncogene-addicted resectable NSCLC.

IMpower150 Final Exploratory Analyses for Atezolizumab Plus Bevacizumab and Chemotherapy in Key NSCLC Patient Subgroups With EGFR Mutations or Metastases in the Liver or Brain

INTRODUCTION

Final overall survival (OS) analyses are presented for EGFR mutations and liver or brain metastases subgroups in the phase III IMpower150 study (NCT02366143) evaluating atezolizumab+bevacizumab+carboplatin/paclitaxel (ABCP) or atezolizumab+carboplatin/paclitaxel (ACP) vs bevacizumab+carboplatin/paclitaxel (BCP).

METHODS

Overall, 1202 patients (intention-to-treat [ITT] population) with chemotherapy-naive, metastatic, nonsquamous non-small cell lung cancer were randomized to ABCP, ACP or BCP. Patients with treated, stable brain metastases were permitted. OS was assessed in EGFR mutations and baseline liver metastases subgroups; rate and time to development (TTD) of new brain metastases was assessed in ITT patients.

RESULTS

At data cutoff (September 13, 2019; median follow-up, 39.3 months), OS improvements were sustained with ABCP versus BCP in sensitizing EGFR mutations (all: hazard ratio [HR] 0.60; 95% CI: 0.31-1.14; prior tyrosine kinase inhibitor [TKI]: HR 0.74; 95% CI: 0.38-1.46) and baseline liver metastases (HR 0.68; 95% CI: 0.45-1.02) subgroups. ACP did not show survival benefit versus BCP in sensitizing EGFR mutations (all: HR 1.0; 95% CI: 0.57-1.74; prior TKI: HR 1.22; 95% CI: 0.68-2.22) or liver metastases (HR 1.01; 95% CI: 0.68-1.51) subgroups. Overall, 100 patients (8.3%) developed new brain metastases. While not formally evaluated, an improvement toward delayed TTD was seen with ABCP vs BCP (HR, 0.68; 95% CI: 0.39-1.19).

CONCLUSIONS

This final exploratory analysis showed OS benefits for ABCP versus BCP in patients with sensitizing EGFR mutations, including those with prior TKI failures, and with liver metastases, although these results should be interpreted with caution. The impact of ABCP on delaying the development of new brain lesions requires further investigation.

Oncogene-specific differences in tumor mutational burden, PD-L1 expression, and outcomes from immunotherapy in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) patients bearing targetable oncogene alterations typically derive limited benefit from immune checkpoint blockade (ICB), which has been attributed to low tumor mutation burden (TMB) and/or PD-L1 levels. We investigated oncogene-specific differences in these markers and clinical outcome.

METHODS

Three cohorts of NSCLC patients with oncogene alterations (n=4189 total) were analyzed. Two clinical cohorts of advanced NSCLC patients treated with ICB monotherapy [MD Anderson (MDACC; n=172) and Flatiron Health-Foundation Medicine Clinico-Genomic Database (CGDB; n=894 patients)] were analyzed for clinical outcome. The FMI biomarker cohort (n=4017) was used to assess the association of oncogene alterations with TMB and PD-L1 expression.

RESULTS

High PD-L1 expression (PD-L1 ≥50%) rate was 19%-20% in classic EGFR, EGFR exon 20 and HER2-mutant tumors, and 34%-55% in tumors with ALK, BRAF V600E, ROS1, RET, or MET alterations. Compared with KRAS-mutant tumors, BRAF non-V600E group had higher TMB (9.6 vs KRAS 7.8 mutations/Mb, p=0.003), while all other oncogene groups had lower TMB (p<0.001). In the two clinical cohorts treated with ICB, molecular groups with EGFR, HER2, ALK, ROS1, RET, or MET alterations had short progression-free survival (PFS; 1.8-3.7 months), while BRAF V600E group was associated with greater clinical benefit from ICB (CGDB cohort: PFS 9.8 months vs KRAS 3.7 months, HR 0.66, p=0.099; MDACC cohort: response rate 62% vs KRAS 24%; PFS 7.4 vs KRAS 2.8 months, HR 0.36, p=0.026). KRAS G12C and non-G12C subgroups had similar clinical benefit from ICB in both cohorts. In a multivariable analysis, BRAF V600E mutation (HR 0.58, p=0.041), PD-L1 expression (HR 0.57, p=0.022), and high TMB (HR 0.66, p<0.001) were associated with longer PFS.

CONCLUSIONS

High TMB and PD-L1 expression are predictive for benefit from ICB treatment in oncogene-driven NSCLCs. NSCLC harboring BRAF mutations demonstrated superior benefit from ICB that may be attributed to higher TMB and higher PD-L1 expression in these tumors. Meanwhile EGFR and HER2 mutations and ALK, ROS1, RET, and MET fusions define NSCLC subsets with minimal benefit from ICB despite high PD-L1 expression in NSCLC harboring oncogene fusions. These findings indicate a TMB/PD-L1-independent impact on sensitivity to ICB for certain oncogene alterations.

AFT-16: Phase II trial of neoadjuvant and adjuvant atezolizumab and chemoradiation (CRT) for stage III non-small cell lung cancer (NSCLC)

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Background: A minority of the approximately 40,000 US patients diagnosed annually with stage III NSCLC can be cured by concurrent CRT. Standard adjuvant immune checkpoint inhibitors (ICI) improve outcome for those patients who complete CRT with good performance status (PS) and without disease progression, but most patients diagnosed with unresectable stage III NSCLC will not meet the criteria for adjuvant ICI. AFT-16 investigated safety and efficacy of neoadjuvant and adjuvant atezolizumab as a strategy that may allow more patients to benefit from ICI. Methods: Eligible patients received 4 cycles (cy) of atezolizumab 1200 mg IV q 21 days followed by CRT with 60 Gy + weekly carboplatin and paclitaxel (CP), CP consolidation and adjuvant atezolizumab to complete 1 year of therapy (17 cy). The primary endpoint of disease control rate at 12 weeks (wks) has been reported. Secondary endpoints reported here include overall response rate, safety, and progression-free and overall survival (PFS, OS) measured from the start of induction therapy. Correlative science data and quality of life endpoints will be reported elsewhere. Results: 64 patients with unresectable stage III NSCLC, PS 0-1 and no active autoimmune disease or significant organ dysfunction were enrolled at 13 Alliance for Clinical Trials in Oncology sites from 11/2017 to 7/2019. 62 patients who received at least one dose of atezolizumab are included in this analysis. Median age was 63.9 years (range 38.1-86.5). Patients were 51.6% female, 77.4% white, 88.7% current & former smokers and 56.5% PS 0. All patients are off study treatment. Mean cycles of treatment received was 9 (1-17). 46 patients were alive at median follow up 24.1 mo (range 3 – 34.1 mo). PFS at 12 and 18 mo from start of induction atezolizumab was 66% (95%CI 55-79) and 57% (95%CI 45-71) respectively. Median PFS was 23.7 mo (95%CI 13.2-NE). OS at 18 mo was 84% (95%CI 75-94). Median OS is not yet estimable. Atezolizumab was well tolerated. One grade (gr) 4 Guillain-Barre syndrome and 1 each gr 3 pneumonia, pneumonitis and colitis were attributable to neoadjuvant atezolizumab. The remaining 9 severe adverse events were unrelated to ICI. Conclusions: Atezolizumab prior to and following CRT for stage III unresectable NSCLC was well tolerated with encouraging PFS and OS without unexpected safety signals. Analysis of correlative endpoints and quality of life are ongoing. Further study of induction atezolizumab is warranted in patients with unresectable stage III NSCLC. Support: https://acknowledgments.alliancefound.org ; Clinical trial information: NCT03102242.

Pooled analyses of immune-related adverse events (irAEs) and efficacy from the phase 3 trials IMpower130, IMpower132, and IMpower150

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Background: PD-L1/PD-1 inhibitors have transformed the treatment (tx) of advanced NSCLC. Evidence suggests that the occurrence of irAEs with these agents may predict improved outcomes in cancers such as NSCLC. Atezolizumab (atezo; anti–PD-L1) has shown efficacy and tolerability in NSCLC and is currently approved in the 1L and 2L+ settings. The Ph 3 IMpower130, IMpower132 and IMpower150 trials evaluated atezo + chemo ± bevacizumab (bev) as 1L tx of NSCLC. We explore the association between irAEs and efficacy in these trials. Methods: Each trial enrolled tx-naive patients (pts) with nonsquamous stage IV NSCLC. Pts were randomized to: carboplatin (carbo) + nab-paclitaxel alone or with atezo in IMpower130; carbo or cisplatin alone or with atezo in IMpower132; atezo (A) + bev (B) + carbo + paclitaxel (CP), ACP or BCP in IMpower150. Data were pooled (data cutoffs: Mar 15 2018 [IMpower130]; May 22 2018 [IMpower132]; Sep 13 2019 [IMpower150]) and analyzed by tx (atezo-containing vs control) and irAE status. A time-dependent Cox model and landmark analyses at 1, 3, 6 and 12 mo were used to control for immortal bias. Study protocols required atezo tx interruption/discontinuation for grade (Gr) ≥3 irAEs. Results: 2503 pts were included in the analysis (atezo, n = 1577; control, n = 926). In both arms, baseline characteristics were generally balanced between pts with irAEs (atezo, n = 753; control, n = 289) and without irAEs (atezo, n = 824; control, n = 637). Any-Gr irAEs occurred in 48% (atezo) and 32% (control) of pts; Gr 3-5 irAEs occurred in 11% (atezo) and 5% (control). The most common irAEs (atezo vs control) were rash (28% vs 18%), hepatitis (lab abnormalities; 15% vs 10%) and hypothyroidism (12% vs 4%). Median time to onset of first irAE was 1.7 (atezo) vs 1.4 mo (control). OS HRs (95% CI) from the time-dependent Cox model between pts with vs without irAEs were 0.69 (0.60, 0.78) in the atezo arm and 0.82 (0.68, 0.99) in the control arm; after excluding rash (perceived as the least specific irAE), OS HRs (95% CI) were 0.75 (0.65, 0.87) and 0.90 (0.71, 1.12), respectively. OS landmark data are in the Table. Conclusions: In this exploratory pooled analysis, pts with irAEs had longer OS vs pts without irAEs in the atezo-containing and control arms per the time-dependent Cox model and landmark analyses; this trend remained for the atezo arm after excluding rash. Landmark analyses suggest that in the atezo arm, pts with Gr 1/2 irAEs had the longest OS and pts with Gr ≥3 irAEs had the shortest OS, potentially due to tx interruption/discontinuation. Clinical trial information: NCT02367781; NCT02657434; NCT02366143. [Table: see text]

AFT-16: Phase II trial of atezolizumab before and after definitive chemoradiation (CRT) for unresectable stage III non-small cell lung cancer (NSCLC)

9045

Background: A minority of the > 40,000 patients (pts) diagnosed with stage III NSCLC annually in the US are cured by CRT, more recently followed by adjuvant immune checkpoint inhibitors (ICI). PD-L1 blockade with CRT may attenuate tumor-related immunosuppression via depletion of regulatory T cells and clonal expansion of effector T cells. Further, CRT may expose otherwise hidden antigens that present additional targets to the reconstituting immune system. Adjuvant ICI has improved survival. Whether ICI before CRT will further improve outcomes is unknown. Methods: This Alliance Foundation Trials (AFT) study evaluated safety and efficacy of atezolizumab before and after CRT. 4 cycles of atezolizumab 1200 mg IV q 21 days with restaging after cycles 2 and 4 were followed by carboplatin and paclitaxel (C/P) weekly with 60 Gy radiation and C/P consolidation followed by atezolizumab for 1 year of therapy. Primary endpoint is disease control rate (DCR) (complete response + partial response (PR) + stable disease (SD)) at 12 weeks (wks). Secondary endpoints include overall response rate, progression-free survival, overall survival, safety and quality of life assessed by EORTC QLQ-30. Correlatives include PD-L1 and tumor mutation burden as predictive biomarkers. Tumor tissue was obtained at study entry; plasma and immune cells were isolated at multiple timepoints. Results: 64 pts with stage III NSCLC, performance status (PS) 0-1, no active autoimmune disease or significant organ dysfunction enrolled at 13 Alliance sites from 11/2017 to 7/2019. 62 pts received ≥ 1 dose of atezolizumab and are included in the primary analysis; median age 63.9 years (38.1-86.5), 51.6% female, 77.4% white, 61.3% former smokers, 56.5% PS 0. DCR at 12 wks was 77.4% (80% confidence interval 69.2-84.3%) (30.7% PR, 46.8% SD). 54 pts reported adverse events (AEs) during induction, mostly grade (gr) 1. There were 13 serious AEs, most unrelated to study treatment; 1 gr 3 anaphylactic reaction, 1 gr 3 colitis, and 1 gr 4 Guillain-Barre syndrome were attributable to atezolizumab. Baseline PD-L1 status was available for 49 pts. DCR was 82.4% for pts with PD-L1 negative and 90.9% for pts with PD-L1 positive tumors. Conclusions: Atezolizumab prior to and following CRT for stage III unresectable NSCLC was well tolerated with an encouraging 12-wk DCR. Analysis of secondary endpoints is ongoing. Further study of induction ICI therapy is warranted in patients with unresectable stage III NSCLC. Support: AFT, Genentech; Clinical trial information: NCT03102242.

IMpower150: Exploratory efficacy analysis in patients (pts) with bulky disease

e21637

Background: In the Ph 3 IMpower150 study (NCT02366143), 1L treatment (tx) with atezolizumab (A) + bevacizumab (B) + carboplatin + paclitaxel (CP; ABCP) significantly improved PFS and OS vs B + CP (BCP) in pts with chemotherapy-naive metastatic (met) nsq NSCLC. As pts with high tumor burden or large size (bulky disease) have poor survival outcomes, an exploratory analysis was conducted to determine whether pts with bulky disease in IMpower150 could derive benefit from ABCP. Methods: 1202 pts (ITT population) were randomized 1:1:1 to ABCP, atezo + CP (ACP) or BCP arms. Doses were given q3w: A, 1200 mg; B, 15 mg/kg; C, AUC 6 mg/mL/min; P, 200 mg/m2. Disease burden subgroups (high or low) were defined using the 3rd quartile of the sum of the longest diameter (SLD) of the target lesions or median number (no.) of met sites at baseline (BL). Exploratory efficacy analyses included PFS, OS, ORR, time to response (TTR) in these subgroups; safety was also assessed. Outcomes are reported for pts enrolled in the ABCP vs BCP arms. Results: Per 3rd quartile SLD (108 mm), 91 ABCP and 85 BCP pts had high disease burden. Per median no. of met sites (median = 2), 210 ABCP and 190 BCP pts had high disease burden. BL characteristics were generally balanced between ABCP and BCP in high disease burden subgroups. With a minimum follow-up of 32.4 mo (data cutoff: Sep 13, 2019), ABCP showed improved OS, PFS and ORR vs BCP in pts with high and low disease burden (Table). High disease burden did not impact TTR. The safety profile of ABCP was comparable between ITT-WT (no EGFR or ALK alterations) pts and high disease burden subgroups. Conclusions: A tx effect for OS, PFS and ORR was seen in pts with and without bulky disease when ABCP vs BCP was compared, regardless of the method used to define “bulky”; TTR was not affected in high disease burden pts. ABCP had a comparable safety profile in bulky disease and ITT-WT pts. ABCP may be a 1L tx option for pts with nsq NSCLC who have high disease burden. Clinical trial information: NCT02366143. [Table: see text]

IMpower150: Exploratory analysis of brain metastases development

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Background: In the global phase III IMpower150 study (NCT02366143), atezolizumab (atezo) + bevacizumab (bev) + chemo (carboplatin + paclitaxel [CP] (ABCP) showed significant improvements in PFS and OS vs BCP in patients with chemotherapy-naive metastatic NSCLC (Socinski et al. N Engl J Med 2018). Because bev has been shown to delay or prevent brain metastases progression in NSCLC (Fu et al. J Chemother 2016; Ilhan-Mutlu et al. Mol Can Ther 2016), exploratory analyses were conducted to assess the development of brain metastases in patients treated with ABCP, BCP and atezo + CP (ACP) in IMpower150. Methods: A total of 1202 patients (intention-to-treat [ITT] population) were randomized 1:1:1 to receive ABCP, ACP or BCP. Doses were given every 3 weeks: atezo 1200 mg, bev 15 mg/kg, carboplatin AUC 6 mg/mL/min and paclitaxel 200 mg/m2. Co-primary endpoints were investigator-assessed PFS and OS in ITT–wild-type (no EGFR or ALK alterations) patients. Exploratory analyses included the rate and time to development (TTD) of new brain metastases in the ITT population, regardless of the presence of baseline brain metastases, as well as safety. Brain scans were performed as clinically indicated, and analyses were based on investigator assessments. Results: With a minimum follow-up of 32.4 months in the ITT population (data cutoff: September 13, 2019), 100 patients had developed brain metastases, with the highest rate of new brain lesions seen in the ACP (11.9%) vs the ABCP (7.0%) and BCP (6.0%) arms (table). Median TTD was not reached in any arm; a trend toward delayed TTD was seen in the ABCP vs BCP arm (HR, 0.68 [95% CI: 0.39, 1.19]). Among patients with and without brain metastases, 17 (35.4%) and 155 (44.0%) in the ACP arm, 18 (64.3%) and 207 (56.7%) in the ABCP arm and 10 (41.7%) and 183 (49.5%) in the BCP arm had Grade 3-4 treatment-related adverse events, respectively. Conclusions: The ACP arm had the highest rate of new brain lesions, whereas the ABCP and BCP arms had similar, lower rates. Taken together with the trend toward delayed development of new brain lesions with ABCP, the data suggest that adding atezo to BCP may not reduce the rate of new brain lesion development but may delay the time to new lesion development. No new safety signals were observed in this exploratory analysis. Clinical trial information: NCT02366143 . [Table: see text]

IMpower150: Analysis of efficacy in patients (pts) with liver metastases (mets)

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Background: Atezolizumab (atezo) + bevacizumab (bev) + chemo (carboplatin + paclitaxel [CP]; ABCP) showed improved PFS and OS vs bev + CP (BCP) in pts with chemo-naive NSCLC (IMpower150). Benefit with ABCP vs BCP extended to key subgroups, including pts with baseline (BL) liver mets, which is a poor prognostic factor in metastatic NSCLC. Similar outcomes were not seen with atezo + chemo (IMpower150 [atezo + CP; ACP]; IMpower130; IMpower132), suggesting that the addition of bev to atezo + chemo is important for conferring clinical benefit in these pts. Here we further explore characteristics and responses of pts with BL liver mets in IMpower150. Methods: 1202 ITT pts were randomized 1:1:1 to receive ABCP, ACP or BCP. Doses were: A, 1200 mg; B, 15 mg/kg; C, AUC 6 mg/mL/min; P, 200 mg/m2. Coprimary endpoints were OS and investigator-assessed PFS in ITT–wild-type pts. Exploratory analyses included efficacy and safety in pts with liver mets. Results: The data capture ≥ 20-mo follow-up in ITT pts (data cutoff: Jan 22, 2018). 162 pts had BL liver mets (ABCP, n = 52; ACP; n = 53; BCP, n = 57), with a median of 3 metastatic sites and median BL tumor SLD of 109 mm (range, 10-249). BL characteristics in these pts were generally balanced across study arms. PFS and OS were improved with ABCP vs BCP (Table). Gr 3-4 treatment-related AEs occurred in 52.1%, 36.5% and 54.5% of pts with liver mets in the ABCP, ACP and BCP arms, respectively. Conclusions: ABCP reduced the risk of death in pts with liver mets by 48% vs BCP and may represent an important new treatment option for this population. Clinical trial information: NCT02366143. [Table: see text]

Pooled analysis of clinical outcome for EGFR TKI-treated patients with EGFR mutation-positive NSCLC

Patients with non-small-cell lung cancer (NSCLC) appear to gain particular benefit from treatment with epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitors (TKI) if their disease tests positive for EGFR activating mutations. Recently, several large, controlled, phase III studies have been published in NSCLC patients with EGFR mutation-positive tumours. Given the increased patient dataset now available, a comprehensive literature search for EGFR TKIs or chemotherapy in EGFR mutation-positive NSCLC was undertaken to update the results of a previously published pooled analysis. Pooling eligible progression-free survival (PFS) data from 27 erlotinib studies (n = 731), 54 gefitinib studies (n = 1802) and 20 chemotherapy studies (n = 984) provided median PFS values for each treatment. The pooled median PFS was: 12.4 months (95% accuracy intervals [AI] 11.6-13.4) for erlotinib-treated patients; 9.4 months (95% AI 9.0-9.8) for gefitinib-treated patients; and 5.6 months (95% AI 5.3-6.0) for chemotherapy. Both erlotinib and gefitinib resulted in significantly longer PFS than chemotherapy (permutation testing; P = 0.000 and P = 0.000, respectively). Data on more recent TKIs (afatinib, dacomitinib and icotinib) were insufficient at this time-point to carry out a pooled PFS analysis on these compounds. The results of this updated pooled analysis suggest a substantial clear PFS benefit of treating patients with EGFR mutation-positive NSCLC with erlotinib or gefitinib compared with chemotherapy.

Evaluation of EGFR protein expression by immunohistochemistry using H-score and the magnification rule: re-analysis of the SATURN study

INTRODUCTION

The phase III SATURN study demonstrated that first-line maintenance erlotinib extended progression-free survival (PFS) and overall survival (OS) versus placebo in patients with advanced non-small cell lung cancer (NSCLC). Analysis of epidermal growth factor receptor (EGFR) expression by immunohistochemistry (IHC) found no significant interaction between EGFR IHC status and PFS (p = 0.63) or OS (p = 0.52). The FLEX study of first-line cetuximab plus chemotherapy demonstrated that EGFR IHC expression was predictive of improved OS with cetuximab when assessed by H-score with a magnification rule. This novel method was used to reassess samples from SATURN.

METHODS

The H-score method assigned a score of 0-300 to each patient, based on the percentage of cells stained at different intensities viewed at various magnifications. The discriminatory threshold was set at 200, per the FLEX study, and existing samples were re-read and classed as low (H-score < 200) or high (≥200) EGFR expression. PFS and OS were re-analyzed based on these new classifications.

RESULTS

In the overall and EGFR wild-type populations, erlotinib provided a consistent survival benefit versus placebo. Hazard ratios (HRs) in the overall population were similar between EGFR IHC-positive and -negative patients for median PFS (HR 0.68 [95% confidence interval (CI) 0.53-0.86] and 0.76 [95% CI 0.62-0.93], respectively) and OS (HR 0.80 [95% CI 0.62-1.05] and 0.80 [95% CI 0.64-1.01] for IHC-positive and IHC-negative, respectively). In the EGFR wild-type population, HRs were again similar between EGFR IHC-positive and -negative subpopulations for PFS (HR 0.69 [95% CI 0.51-0.95] and 0.84 [95% CI 0.63-1.12], respectively) and OS (HR 0.78 [95% CI 0.55-1.10] and 0.76 [95% CI 0.55-1.05], respectively).

CONCLUSIONS

These data suggest that EGFR IHC does not have value as a marker to predict erlotinib benefit in the first-line maintenance setting for advanced NSCLC.

Pathophysiology of bronchial smooth muscle remodelling in asthma

Whereas the role of bronchial smooth muscle remains controversial in healthy subjects its role is well established in asthmatics. Bronchial smooth muscle contraction induces airway narrowing. The smooth muscle also contributes to bronchial inflammation by secreting a range of inflammatory mediators, recruiting and activating inflammatory cells, such as mast cells or T-lymphocytes. In addition, bronchial smooth muscle mass is significantly increased in asthma. Such an increase has been related to a deposition of extracellular matrix proteins, and an increase in both cell size and number. However, the mechanisms of this smooth muscle remodelling are complex and not completely understood. The article will review recent data regarding the pathophysiology of bronchial smooth muscle remodelling in asthma.

Validated assay for the quantification of anastrozole in human plasma by capillary gas chromatography-63Ni electron capture detection

An assay was developed for the quantification of anastrozole [2,2'-[5-(1H-1,2,4-triazol-1-ymethyl)-1,3-phenylene]bis(2-++ +methylpropiononitrile)] in human plasma using liquid-liquid extraction. Anastrozole and an internal standard were chromatographed and detected by gas chromatography with electron capture detection, using a combination temperature-pressure program. The range of the assay is 3 to 100 ng/ml. Anastrozole was quantified by comparing its peak area to that of an internal standard. A cross-validation of this assay was also successfully performed between several laboratories.