A Blood-based Assay for Assessment of Tumor Mutational Burden in First-line Metastatic NSCLC Treatment: Results from the MYSTIC Study.

PURPOSE: Tumor mutational burden (TMB) has been shown to be predictive of survival benefit in patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors. Measuring TMB in the blood (bTMB) using circulating cell-free tumor DNA (ctDNA) offers practical advantages compared with TMB measurement in tissue (tTMB); however, there is a need for validated assays and identification of optimal cutoffs. We describe the analytic validation of a new bTMB algorithm and its clinical utility using data from the phase III MYSTIC trial. PATIENTS AND METHODS: The dataset used for the clinical validation was from MYSTIC, which evaluated first-line durvalumab (anti-PD-L1 antibody) ± tremelimumab (anticytotoxic T-lymphocyte-associated antigen-4 antibody) or chemotherapy for metastatic NSCLC. bTMB and tTMB were evaluated using the GuardantOMNI and FoundationOne CDx assays, respectively. A Cox proportional hazards model and minimal P value cross-validation approach were used to identify the optimal bTMB cutoff. RESULTS: In MYSTIC, somatic mutations could be detected in ctDNA extracted from plasma samples in a majority of patients, allowing subsequent calculation of bTMB. The success rate for obtaining valid TMB scores was higher for bTMB (809/1,001; 81%) than for tTMB (460/735; 63%). Minimal P value cross-validation analysis confirmed the selection of bTMB ≥20 mutations per megabase (mut/Mb) as the optimal cutoff for clinical benefit with durvalumab + tremelimumab. CONCLUSIONS: Our study demonstrates the feasibility, accuracy, and reproducibility of the GuardantOMNI ctDNA platform for quantifying bTMB from plasma samples. Using the new bTMB algorithm and an optimal bTMB cutoff of ≥20 mut/Mb, high bTMB was predictive of clinical benefit with durvalumab + tremelimumab versus chemotherapy.

Durvalumab With or Without Tremelimumab vs Standard Chemotherapy in First-line Treatment of Metastatic Non-Small Cell Lung Cancer: The MYSTIC Phase 3 Randomized Clinical Trial.

Importance: Checkpoint inhibitors targeting programmed cell death 1 or its ligand (PD-L1) as monotherapies or in combination with anti-cytotoxic T-lymphocyte-associated antigen 4 have shown clinical activity in patients with metastatic non-small cell lung cancer. Objective: To compare durvalumab, with or without tremelimumab, with chemotherapy as a first-line treatment for patients with metastatic non-small cell lung cancer. Design, Setting, and Participants: This open-label, phase 3 randomized clinical trial (MYSTIC) was conducted at 203 cancer treatment centers in 17 countries. Patients with treatment-naive, metastatic non-small cell lung cancer who had no sensitizing EGFR or ALK genetic alterations were randomized to receive treatment with durvalumab, durvalumab plus tremelimumab, or chemotherapy. Data were collected from July 21, 2015, to October 30, 2018. Interventions: Patients were randomized (1:1:1) to receive treatment with durvalumab (20 mg/kg every 4 weeks), durvalumab (20 mg/kg every 4 weeks) plus tremelimumab (1 mg/kg every 4 weeks, up to 4 doses), or platinum-based doublet chemotherapy. Main Outcomes and Measures: The primary end points, assessed in patients with ≥25% of tumor cells expressing PD-L1, were overall survival (OS) for durvalumab vs chemotherapy, and OS and progression-free survival (PFS) for durvalumab plus tremelimumab vs chemotherapy. Analysis of blood tumor mutational burden (bTMB) was exploratory. Results: Between July 21, 2015, and June 8, 2016, 1118 patients were randomized. Baseline demographic and disease characteristics were balanced between treatment groups. Among 488 patients with ≥25% of tumor cells expressing PD-L1, median OS was 16.3 months (95% CI, 12.2-20.8) with durvalumab vs 12.9 months (95% CI, 10.5-15.0) with chemotherapy (hazard ratio [HR], 0.76; 97.54% CI, 0.56-1.02; P = .04 [nonsignificant]). Median OS was 11.9 months (95% CI, 9.0-17.7) with durvalumab plus tremelimumab (HR vs chemotherapy, 0.85; 98.77% CI, 0.61-1.17; P = .20). Median PFS was 3.9 months (95% CI, 2.8-5.0) with durvalumab plus tremelimumab vs 5.4 months (95% CI, 4.6-5.8) with chemotherapy (HR, 1.05; 99.5% CI, 0.72-1.53; P = .71). Among 809 patients with evaluable bTMB, those with a bTMB ≥20 mutations per megabase showed improved OS for durvalumab plus tremelimumab vs chemotherapy (median OS, 21.9 months [95% CI, 11.4-32.8] vs 10.0 months [95% CI, 8.1-11.7]; HR, 0.49; 95% CI, 0.32-0.74). Treatment-related adverse events of grade 3 or higher occurred in 55 (14.9%) of 369 patients who received treatment with durvalumab, 85 (22.9%) of 371 patients who received treatment with durvalumab plus tremelimumab, and 119 (33.8%) of 352 patients who received treatment with chemotherapy. These adverse events led to death in 2 (0.5%), 6 (1.6%), and 3 (0.9%) patients, respectively. Conclusions and Relevance: The phase 3 MYSTIC study did not meet its primary end points of improved OS with durvalumab vs chemotherapy or improved OS or PFS with durvalumab plus tremelimumab vs chemotherapy in patients with ≥25% of tumor cells expressing PD-L1. Exploratory analyses identified a bTMB threshold of ≥20 mutations per megabase for optimal OS benefit with durvalumab plus tremelimumab. Trial Registration: ClinicalT rials.gov Identifier: NCT02453282.

Continued use of afatinib with the addition of cetuximab after progression on afatinib in patients with EGFR mutation-positive non-small-cell lung cancer and acquired resistance to gefitinib or erlotinib.

OBJECTIVES: In a phase Ib trial, afatinib plus cetuximab demonstrated promising clinical activity (objective response rate [ORR]: 29%; median progression-free survival [PFS]: 4.7 months) in patients with epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC) with acquired resistance to erlotinib or gefitinib. Here, a separate cohort exploring afatinib plus cetuximab after progression on afatinib is reported. MATERIALS AND METHODS: Patients with EGFR mutation-positive NSCLC who progressed on erlotinib or gefitinib received afatinib 40mg daily until progression, followed by afatinib daily plus cetuximab 500mg/m2 every 2 weeks until progression or intolerable adverse events (AEs). Endpoints included safety, ORR, and PFS. RESULTS: Thirty-seven patients received afatinib monotherapy. Two (5%) patients responded; median PFS was 2.7 months. Thirty-six patients transitioned to afatinib plus cetuximab. Four (11%) patients responded; median PFS was 2.9 months. Median PFS with afatinib plus cetuximab for patients who received afatinib monotherapy for ≥12 versus <12 weeks was 4.9 versus 1.8 months (p=0.0354), and for patients with T790M-positive versus T790M-negative tumors was 4.8 versus 1.8 months (p=0.1306). Fifty percent of patients receiving afatinib plus cetuximab experienced drug-related grade 3/4 AEs. The most frequent drug-related AEs (any grade) were diarrhea (70%), rash (49%), and fatigue (35%) with afatinib monotherapy and rash (69%), paronychia (39%), and dry skin (36%) with afatinib plus cetuximab. CONCLUSION: Sequential EGFR blockade with afatinib followed by afatinib plus cetuximab had a predictable safety profile and demonstrated modest activity in patients with EGFR mutation-positive NSCLC with resistance to erlotinib or gefitinib. CLINICALTRIALS. GOV IDENTIFIER: NCT01090011.

Afatinib versus erlotinib as second-line treatment of patients with advanced squamous cell carcinoma of the lung (LUX-Lung 8): an open-label randomised controlled phase 3 trial.

BACKGROUND: There is a major unmet need for effective treatments in patients with squamous cell carcinoma of the lung. LUX-Lung 8 compared afatinib (an irreversible ErbB family blocker) with erlotinib (a reversible EGFR tyrosine kinase inhibitor), as second-line treatment for patients with advanced squamous cell carcinoma of the lung. METHODS: We did this open-label, phase 3 randomised controlled trial at 183 cancer centres in 23 countries worldwide. We enrolled adults with stage IIIB or IV squamous cell carcinoma of the lung who had progressed after at least four cycles of platinum-based-chemotherapy. Participants were randomly assigned (1:1) to receive afatinib (40 mg per day) or erlotinib (150 mg per day) until disease progression. The randomisation was done centrally with an interactive voice or web-based response system and stratified by ethnic origin (eastern Asian vs non-eastern Asian). Clinicians and patients were not masked to treatment allocation. The primary endpoint was progression-free survival assessed by independent central review (intention-to-treat population). The key secondary endpoint was overall survival. This trial is registered with ClinicalTrials.gov, NCT01523587. FINDINGS: 795 eligible patients were randomly assigned (398 to afatinib, 397 to erlotinib). Median follow-up at the time of the primary analysis of progression-free survival was 6·7 months (IQR 3·1-10·2), at which point enrolment was not complete. Progression free-survival at the primary analysis was significantly longer with afatinib than with erlotinib (median 2·4 months [95% CI 1·9-2·9] vs 1·9 months [1·9-2·2]; hazard ratio [HR] 0·82 [95% CI 0·68-1·00], p=0·0427). At the time of the primary analysis of overall survival (median follow-up 18·4 months [IQR 13·8-22·4]), overall survival was significantly greater in the afatinib group than in the erloinib group (median 7·9 months [95% CI 7·2-8·7] vs 6·8 months [5·9-7·8]; HR 0·81 [95% CI 0·69-0·95], p=0·0077), as were progression-free survival (median 2·6 months [95% CI 2·0-2·9] vs 1·9 months [1·9-2·1]; HR 0·81 [95% CI 0·69-0·96], p=0·0103) and disease control (201 [51%] of 398 patients vs 157 [40%] of 397; p=0·0020). The proportion of patients with an objective response did not differ significantly between groups (22 [6%] vs 11 [3%]; p=0·0551). Tumour shrinkage occurred in 103 (26%) of 398 patients versus 90 (23%) of 397 patients. Adverse event profiles were similar in each group: 224 (57%) of 392 patients in the afatinib group versus 227 (57%) of 395 in the erlotinib group had grade 3 or higher adverse events. We recorded higher incidences of treatment-related grade 3 diarrhoea with afatinib (39 [10%] vs nine [2%]), of grade 3 stomatitis with afatinib (16 [4%] vs none), and of grade 3 rash or acne with erlotinib (23 [6%] vs 41 [10%]). INTERPRETATION: The significant improvements in progression-free survival and overall survival with afatinib compared with erlotinib, along with a manageable safety profile and the convenience of oral administration suggest that afatinib could be an additional option for the treatment of patients with squamous cell carcinoma of the lung. FUNDING: Boehringer Ingelheim.

Phase II study of afatinib, an irreversible ErbB family blocker, in demographically and genotypically defined lung adenocarcinoma.

OBJECTIVES: Afatinib, an oral irreversible ErbB family blocker, has demonstrated efficacy in patients with epidermal growth factor receptor (EGFR) mutation-positive advanced lung adenocarcinoma. Other potential biomarkers predicting response to afatinib, such as human epidermal growth factor receptor-2 (HER2) mutations and EGFR gene amplification, have not been validated yet. This phase II study investigated whether afatinib conferred clinical benefit in cohorts of adenocarcinoma patients with: (1) EGFR mutation and failing on erlotinib/gefitinib; or (2) increased copy number of EGFR by fluorescence in situ hybridization (FISH); or (3) HER2 mutation. MATERIALS AND METHODS: Patients started daily afatinib 50mg monotherapy. Upon disease progression, patients could continue, at the investigator's discretion, afatinib (40mg) with the addition of paclitaxel (80mg/m(2) weekly for 3 weeks/4-week cycle). Endpoints included confirmed objective response (OR), progression-free survival (PFS), disease control, and safety. RESULTS: Of 41 patients treated (cohort 1: n=32; cohort 2: n=2; cohort 3: n=7), 33 received afatinib monotherapy; eight subsequently received afatinib plus paclitaxel. With afatinib monotherapy, one patient achieved a confirmed OR (partial response [PR]; cohort 2). Two further patients achieved unconfirmed PRs (one each in cohort 1 and cohort 3). Disease control was achieved by 17/32 (53%), 2/2 (100%) and 5/7 (71%) patients in cohorts 1, 2 and 3, respectively. In patients receiving combination therapy (median PFS: 6.7 weeks), one (cohort 3) had confirmed PR of 41.9 weeks. The most common afatinib-related adverse events were diarrhea (95%) and rash/acne (80%). CONCLUSION: Afatinib demonstrated signs of clinical activity in heavily pretreated patients with activating HER2 or EGFR mutations or EGFR FISH-positive tumors.

A phase I, dose-escalation trial of continuous- and pulsed-dose afatinib combined with pemetrexed in patients with advanced solid tumors.

INTRODUCTION: Afatinib, an irreversible ErbB family blocker, demonstrated synergistic inhibition of epidermal growth factor receptor-mutant cell growth with pemetrexed. This phase I study investigated the maximum tolerated dose (MTD), safety, pharmacokinetics, and antitumor activity of afatinib plus pemetrexed in patients with advanced solid tumors. METHODS: In a 3 + 3 dose-escalation design, patients were given intravenous pemetrexed (500 mg/m(2)) on day 1 of a 21-day cycle (maximum 6 cycles), combined with continuous daily oral afatinib (schedule A [SA]; starting dose 30 mg, escalation to 50 mg) or pulsed-dose daily oral afatinib (schedule B [SB]; starting dose 50 mg, escalation to 70 mg) on days 1-6 of each 21-day cycle. Primary endpoint was determination of MTD based on dose-limiting toxicities (DLTs) in cycle 1. RESULTS: Fifty-three patients were treated (SA: n = 23; SB: n = 30). Eight patients had DLTs in SA, 11 patients in SB; diarrhea and fatigue were the most common. MTD of afatinib was 30 mg in SA and 50 mg in SB. Six patients in SA and eight in SB completed 6 treatment cycles. One patient in each schedule had confirmed objective response; 18/53 patients had disease control (SA: n = 7; SB: n = 11). Most frequent drug-related adverse events were diarrhea, rash, fatigue, and stomatitis. No relevant pharmacokinetic interactions were observed. CONCLUSIONS: Continuous- or pulsed-dose afatinib combined with pemetrexed exhibited a manageable safety profile. Pulsed dosing conferred no apparent safety or dose advantage. Continuous-dose afatinib 30 mg/day with pemetrexed is recommended for phase II studies.

Dual inhibition of EGFR with afatinib and cetuximab in kinase inhibitor-resistant EGFR-mutant lung cancer with and without T790M mutations.

UNLABELLED: EGFR-mutant lung cancers responsive to reversible EGFR inhibitors (gefitinib/erlotinib) develop acquired resistance, mediated by second-site EGFR T790M mutation in >50% of cases. Preclinically, afatinib (irreversible ErbB family blocker) plus cetuximab (anti-EGFR monoclonal antibody) overcomes T790M-mediated resistance. This phase Ib study combining afatinib and cetuximab enrolled heavily pretreated patients with advanced EGFR-mutant lung cancer and acquired resistance to erlotinib/gefitinib. Patients provided post-acquired-resistance tumor samples for profiling EGFR mutations. Among 126 patients, objective response rate (overall 29%) was comparable in T790M-positive and T790M-negative tumors (32% vs. 25%; P = 0.341). Median progression-free survival was 4.7 months (95% confidence interval, 4.3-6.4), and the median duration of confirmed objective response was 5.7 months (range, 1.8-24.4). Therapy-related grade 3/4 adverse events occurred in 44%/2% of patients. Afatinib-cetuximab demonstrated robust clinical activity and a manageable safety profile in EGFR-mutant lung cancers with acquired resistance to gefitinib or erlotinib, both with and without T790M mutations, warranting further investigation. SIGNIFICANCE: This article reports the results of a trial combining afatinib and cetuximab in patients with acquired resistance and details the first clinical proof-of-concept for the preclinical hypothesis that a significant proportion of tumors in patients with acquired resistance to gefitinib/erlotinib remain dependent on EGFR signaling for survival.

Phase 2 trial of afatinib, an ErbB family blocker, in solid tumors genetically screened for target activation.

BACKGROUND: The efficacy of afatinib, an irreversible ErbB Family Blocker, was evaluated in patients who had 1 of 4 categories of solid tumors with epidermal growth factor receptor/human epidermal growth factor receptor 2 (EGFR/HER2) gene amplification or EGFR-activating mutations. METHODS: Patients with previously treated but ErbB inhibitor-naive esophagogastric, biliary tract, urothelial tract, or gynecologic cancers (lung cancers were excluded) harboring EGFR/HER2 gene amplification or high polysomy were identified by fluorescence in situ hybridization (FISH). Tumors were also screened for EGFR mutations. The primary endpoint was the objective response rate; secondary endpoints included the clinical benefit rate, pharmacokinetics, and safety. RESULTS: Of 385 prescreened patients, 38 had FISH-positive tumors (10 with EGFR amplification and 29 with HER2 amplification or high polysomy [1 tumor had EGFR/HER2 high polysomy]; none had EGFR-activating mutations), and 20 patients received treatment with afatinib 50 mg daily. The objective response rate was 5% (1 of 20 patients), and the best objective response included 1 complete response. Eight patients experienced stable disease. The most frequently reported adverse events were diarrhea, rash, and decreased appetite. The trial closed early because of slow recruitment. CONCLUSIONS: Single-agent afatinib activity was limited, yet encouraging, in selected tumors that were screened prospectively for target activation. The implementation of a biomarker-driven approach using a low-frequency biomarker for patient selection across multiple tumor types can be challenging.

Neutropenia and febrile neutropenia in patients with Hodgkin's lymphoma treated with doxorubicin (Adriamycin), bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy.

When uncomplicated neutropenia during doxorubicin (Adriamycin), bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy for the treatment of Hodgkin's lymphoma is encountered, it is unclear whether or not treatment should be modified. In the present study, we determined the incidence of neutropenia, febrile neutropenia, and the relationship of febrile neutropenia to grade III/IV neutropenia and dose modification, in a large university patient population. We reviewed the charts of patients diagnosed with Hodgkin's lymphoma between 1 January 1990 and 31 December 2002 who were treated with ABVD chemotherapy, and seen at the University of Iowa with complete diagnosis, staging, and treatment dosing records. Adequate data was available on 894 treatments in 81 patients with Hodgkin's lymphoma treated with ABVD chemotherapy. Grade III/IV neutropenia was present on the scheduled day of treatment in 187 (20.9%) treatments in 64 (79%) patients. Grade III/IV neutropenia was most common at cycle 1 day 15. Febrile neutropenia developed nine times in eight patients, and eight episodes of febrile neutropenia developed when the treatment-day absolute neutrophil count (ANC) > or =1000. Dose delay of >4 days and/or dose reduction to <80% of original doxorubicin dose following grade III/IV neutropenia occurred in 29 of 187 treatments, with no episodes of febrile neutropenia. With grade III/IV neutropenia on the day of therapy, 158 treatments were administered without dose reduction or dose delay with one subsequent episode of febrile neutropenia. Neutropenia during ABVD is common, and dose modification for uncomplicated neutropenia on the day of treatment may not reduce the risk of febrile neutropenia. It may be possible to maintain dose intensity in the face of uncomplicated neutropenia during ABVD therapy.