Atezolizumab as the First Systemic Therapy Approved for Alveolar Soft Part Sarcoma.

OBJECTIVE: The objective was to review the pharmacology, efficacy, and safety of atezolizumab (Tecentriq) for the treatment of adult and pediatric patients aged 2 years and older with unresectable or metastatic alveolar soft part sarcoma (ASPS). DATA SOURCES: A literature search was conducted using PubMed and MEDLINE databases, published abstracts, and ongoing studies from ClinicalTrials.gov between January 1, 1981, and May 31, 2023. Keywords included atezolizumab, Tecentriq, MPDL3280, immunotherapy, PD-L1, PD-1, pediatrics, sarcoma, and ASPS. STUDY SELECTION AND DATA EXTRACTION: All English-language studies involving atezolizumab for ASPS were included and discussed. DATA SYNTHESIS: Atezolizumab is an anti-programmed death-ligand 1 (PD-L1) monoclonal antibody designed to block the interaction between PD-L1 and the programmed cell death protein 1 (PD-1) receptor. Atezolizumab was granted approval by the FDA specifically for ASPS based on a phase II clinical trial in adult and pediatric patients (n = 49), which reported an overall response rate of 24% and a durable response rate at 6 and 12 months of 67% and 42%, respectively. Common grade 3/4 adverse reactions include musculoskeletal pain (8%), followed by hypertension (6%), weight gain (6%), headache (4%), and dizziness (4%). RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON WITH EXISTING DRUGS: Advanced ASPS is a high-risk disease with limited treatment options. Atezolizumab appears to be a viable treatment option in ASPS demonstrating clinical efficacy and a manageable toxicity profile. CONCLUSIONS: With no other treatments that are FDA approved specifically for ASPS, and few demonstrating efficacy in the advanced setting, the approval of atezolizumab, including the first approval for pediatric patients, represents a landmark improvement to the therapeutic arsenal against this rare disease.

De-glycosylated membrane PD-L1 in tumor tissues as a biomarker for responsiveness to atezolizumab (Tecentriq) in advanced breast cancer patients.

The atezolizumab (Tecentriq), a humanized antibody against human programmed death ligand 1 (PD-L1), combined with nab-paclitaxel was granted with accelerated approval to treat unresectable locally advanced or metastatic triple-negative breast cancer (TNBC) due to the encouraging positive results of the phase 3 IMpassion130 trial using PD-L1 biomarker from immune cells to stratify patients. However, the post-market study IMpassion131 did not support the original observation, resulting in the voluntary withdrawal of atezolizumab from the indication in breast cancer by Genentech in 2021. Emerging evidence has revealed a high frequency of false negative result using the standard immunohistochemical (IHC) staining due to heavy glycosylation of PD-L1. The removal of glycosylation prevents from the false negative staining, enabling more accurate assessment of PD-L1 levels and improving prediction for response to immune checkpoint therapy. In the present study, the natural and de-glycosylated PD-L1 expression in tumor and immune cells from nine TNBC patients were analyzed by using clone 28-8 monoclonal antibody to correlate with treatment outcome. Our results demonstrate that: (1) Removal of the glycosylation indeed enhances the detection of PD-L1 by IHC staining, (2) The PD-L1 levels on tumor cell surface after removal of the glycosylation correlates well with clinical responses for atezolizumab treatment; (3) The criteria used in the IMpassion130 and IMpassion131 trials which scored the natural PD-L1 in the immune cells failed to correlate with the clinical response. Taken together, tumor cell surface staining of PD-L1 with de-glycosylation has a significant correlation with the clinical response for atezolizumab treatment, suggesting that treatment of atezolizumab may be worthy of further consideration with de-glycosylation procedure as a patient stratification strategy. A larger cohort to validate this important issue is warranted to ensure right patient population who could benefit from the existing FDA-approved drugs.

The European Medicines Agency review of the initial application of atezolizumab and the role of PD-L1 expression as biomarker for checkpoint inhibitors.

Immune checkpoint inhibitors have revolutionised cancer therapeutics. Translational research evaluating the role of biomarkers is essential to identify the ideal target population for these drugs. From a regulatory perspective, the identification of biomarkers and diagnostic assays is strongly encouraged by the European Medicines Agency (EMA). The aim of this article is to analyse the role of programmed death-ligand 1 (PD-L1) expression as a predictive biomarker in relation to the data submitted for the initial assessment of atezolizumab, a monoclonal antibody targeting human PD-L1. On 20 July 2017, atezolizumab was granted a marketing authorisation valid throughout the European Union (EU) for adult patients with (i) locally advanced or metastatic non-small-cell lung cancer (NSCLC) after chemotherapy and (ii) locally advanced or metastatic urothelial carcinoma (UC) after chemotherapy or cisplatin-ineligibility. Initially, these indications were not restricted by the level of PD-L1 expression, but preliminary data from an ongoing phase III trial in patients with UC led to a restriction in the UC indication to cisplatin-ineligible patients whose tumours have ≥5% PD-L1 expression. Still, the role of PD-L1 expression as predictive biomarker for atezolizumab therapy remains inconclusive and further research is needed. Data in this paper came from the scientific review leading to the initial regulatory approval of atezolizumab in the EU and its complementary application for indication (EMEA/H/C/004143/II/0010). The full scientific assessment report and product information are available on the EMA website (www.ema.europa.eu).

Safety and patient-reported outcomes of atezolizumab, carboplatin, and etoposide in extensive-stage small-cell lung cancer (IMpower133): a randomized phase I/III trial.

BACKGROUND: The addition of atezolizumab to carboplatin and etoposide (CP/ET) significantly improved progression-free and overall survival for patients with extensive-stage small-cell lung cancer (ES-SCLC) in the IMpower133 study (NCT02763579). We have evaluated adverse events (AEs) and patient-reported outcomes in IMpower133 to assess the benefit-risk profile of this regimen. PATIENTS AND METHODS: Patients received four 21-day cycles of CP/ET plus intravenous atezolizumab 1200 mg or placebo (induction phase), followed by atezolizumab or placebo (maintenance phase) until progression or loss of benefit. AEs were assessed and patient-reported outcomes were evaluated every 3 weeks during treatment using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 (QLQ-C30) and QLQ-LC13. RESULTS: Overall, 394 patients were assessable for safety in the induction phase and 318 in the maintenance phase. The frequency of AEs, grade 3-4 AEs, and serious AEs was similar between arms in both phases. Immune-related AEs were more frequent in the atezolizumab arm during both induction (28% versus 17%; leading to atezolizumab/placebo interruption 9% versus 5%, leading to withdrawal 4% versus 0%) and maintenance (26% versus 15%; leading to atezolizumab/placebo interruption, 3% versus 2%, leading to withdrawal 1% versus 1%), most commonly rash (induction 11% versus 9%, maintenance 14% versus 4%), and hypothyroidism (induction 4.0% versus 0%, maintenance 10% versus 1%). Changes in patient-reported treatment-related symptoms commonly associated with quality of life impairment were generally similar during induction and most of the maintenance phase. Patient-reported function and health-related quality of life (HRQoL) improved in both arms after initiating treatment, with more pronounced and persistent HRQoL improvements in the atezolizumab arm. CONCLUSIONS: In patients with ES-SCLC, atezolizumab plus CP/ET has a comparable safety profile to placebo plus CP/ET, and the addition of atezolizumab did not adversely impact patient-reported HRQoL. These data demonstrate the positive benefit-risk profile of first-line atezolizumab plus CP/ET in ES-SCLC and further support this regimen as a new standard of care in this setting. CLINICAL TRIALS NUMBER: NCT02763579.

Subgroup Analysis of Japanese Patients in a Phase III Study of Atezolizumab in Extensive-stage Small-cell Lung Cancer (IMpower133).

BACKGROUND: Atezolizumab is effective and well-tolerated in patients with extensive-stage small-cell lung cancer (ES-SCLC), but differences in response to systemic therapy exist between Asian and Caucasian patients. Here, we assess the efficacy and tolerability of atezolizumab in Japanese patients from the IMpower133 trial (NCT02763579). PATIENTS AND METHODS: Key eligibility criteria for this multicenter, double-blind, placebo-controlled, randomized study included age ≥ 18 years; histologically or cytologically confirmed ES-SCLC, measurable per Response Evaluation Criteria in Solid Tumors version 1.1; an Eastern Cooperative Oncology Group performance status of 0/1; and no prior systemic treatment for ES-SCLC. Patients were treated with either atezolizumab 1200 mg or placebo with carboplatin (area under the curve of 5 mg/mL/min) and etoposide (100 mg/m2). Primary endpoints were overall survival and investigator-assessed progression-free survival in the intention-to-treat population. Of the 403 patients randomized in the IMpower133 trial, 42 were enrolled at Japanese centers. RESULTS: In Japanese patients in the intention-to-treat population, the median overall survival in the atezolizumab group (n = 20) was longer than that in the placebo group (n = 22; 14.6 months; 95% confidence interval [CI], 11.8-17.8 months vs. 11.9 months; 95% CI, 8.4-15.8, respectively; hazard ratio, 0.72; 95% CI, 0.31-1.67). The median progression-free survival was 4.5 months (95% CI, 4.2-8.1 months) versus 4.0 months (95% CI, 2.9-5.6 months; hazard ratio, 0.47; 95% CI, 0.23-0.96), respectively. Atezolizumab was generally well-tolerated, with no treatment-related deaths. CONCLUSION: The addition of atezolizumab to carboplatin and etoposide was effective and well-tolerated in Japanese patients with ES-SCLC. Results are consistent with the primary analysis of the IMpower133 trial.

Atezolizumab in Japanese Patients With Previously Treated Advanced Non-Small-Cell Lung Cancer: A Subgroup Analysis of the Phase 3 OAK Study.

INTRODUCTION: Atezolizumab, an anti-programmed death-ligand 1 (PD-L1) agent, is effective and well tolerated in patients with pretreated advanced non-small-cell lung cancer (NSCLC). We assessed its efficacy and safety in Japanese patients through subgroup analyses of the phase 3 OAK study (NCT02008227). PATIENTS AND METHODS: Key eligibility criteria of this randomized, controlled, open-label, international study include locally advanced/metastatic NSCLC, ≥ 1 prior platinum-based chemotherapy, age ≥ 18 years, measurable disease (Response Evaluation Criteria in Solid Tumors v1.1), and Eastern Cooperative Oncology Group performance status 0 or 1. Atezolizumab 1200 mg or docetaxel 75 mg/m2 was provided intravenously every 3 weeks. Co-primary end points were overall survival (OS) in the intention-to-treat (ITT) population and those with ≥ 1% PD-L1 expression on tumor cells (TC) or tumor-infiltrating immune cells (IC; TC1/2/3 or IC1/2/3). RESULTS: Sixty-four ITT patients were Japanese; 19 had TC1/2/3 or IC1/2/3 status. In Japanese ITT patients, median OS in the atezolizumab arm (n = 36) was longer than the docetaxel arm (n = 28; 21.3 months [95% confidence interval (CI), 11.0-not estimable (NE)] versus 17.0 months [95% CI, 12.5-NE], respectively; hazard ratio 0.80 [95% CI, 0.41-1.57]). In the TC1/2/3 or IC1/2/3 population, median OS was 21.3 months (95% CI, 15.0-NE) and NE in the atezolizumab (n = 11) and docetaxel (n = 8) groups, respectively (hazard ratio, 0.81 [95% CI, 0.22-3.05]). Atezolizumab was generally well tolerated, with no treatment-related deaths. CONCLUSION: Atezolizumab was effective and well tolerated in pretreated Japanese patients with NSCLC. Results are consistent with the primary analysis of OAK.

Checkpoint inhibitors: a cutting edge in oncology.

The checkpoint inhibitor field, and indeed the whole of immuno-oncology, is fast-paced and fascinating, with huge clinical and commercial potential. The challenge in the coming years will be to define the best type and combination of immunotherapy, and the best target population to receive it. Keytruda's ground-breaking approval for a biomarker-based rather than location-based indication is a solid step in this direction, and is likely to be followed by other such approvals. As the field develops, it is to be hoped that immuno-oncology therapeutics will continue to deliver the significant improvements in patient outcome that have been seen so far.

Precision medicine in immune checkpoint blockade therapy for non-small cell lung cancer.

Immune checkpoint blockade therapy by targeting the programmed death protein 1/programmed death ligand 1 (PD-L1) axis using antibodies has yielded promising clinical responses in patients with non-small cell lung cancer (NSCLC). However, owing to the dynamic expression of PD-L1, degree of mutational/neoantigen load, intratumoral heterogeneity, infiltrated immune cells of tumor microenvironment of NSCLC, the response rates to these agents are limited, despite several companion diagnostic assays by detecting PD-L1 in tumor cells have been introduced into clinical practice. Therefore, in this era of precision medicine, there is an urgent need for predictive biomarkers to identify NSCLC patients likely to benefit from this novel therapy.