A first-in-human study of the anti-LAG-3 antibody favezelimab plus pembrolizumab in previously treated, advanced microsatellite stable colorectal cancer.

BACKGROUND: Treatment options are limited for participants with microsatellite stable (MSS) metastatic colorectal cancer (mCRC) that progressed after two or more prior therapies. Studies have shown that blockade of both lymphocyte-activation gene 3 (LAG-3) and programmed cell death protein 1 (PD-1) can improve antitumor activity. Here, we evaluate the antitumor activity of the LAG-3 antibody favezelimab alone or in combination with pembrolizumab in participants with MSS mCRC. PATIENTS AND METHODS: Eligible participants with MSS PD-1/programmed death-ligand 1 (PD-L1) treatment-naive mCRC that progressed on two or more prior therapies received 800 mg favezelimab, 800 mg favezelimab plus 200 mg pembrolizumab, or 800 mg favezelimab/200 mg pembrolizumab co-formulation, every 3 weeks. The primary endpoint was safety, the secondary endpoint was objective response rate (ORR), and exploratory endpoints included duration of response, progression-free survival (PFS), and overall survival (OS). RESULTS: At the data cut-off date of 23 October 2020, a total of 20 participants received favezelimab alone, 89 received favezelimab plus pembrolizumab (including as favezelimab/pembrolizumab co-formulation); 48 had PD-L1 combined positive score (CPS) ≥1 tumors. At this interim analysis median follow-up was 5.8 months with favezelimab and 6.2 with favezelimab plus pembrolizumab. Treatment-related adverse events (TRAEs) were 65% with favezelimab and 65.2% with favezelimab plus pembrolizumab. Grade ≥3 TRAEs were 15% with favezelimab and 20% with favezelimab plus pembrolizumab. No grade 5 TRAEs occurred. Common TRAEs (≥15%) included fatigue (20.0%), nausea (15.0%) with favezelimab, and fatigue (16.9%) with favezelimab plus pembrolizumab. Confirmed ORR was 6.3% with favezelimab plus pembrolizumab, with median duration of response of 10.6 months (range 5.6-12.7 months), median OS of 8.3 months (95% confidence interval 5.5-12.9 months), and median PFS of 2.1 months (1.9-2.2 months). In an exploratory analysis of PD-L1 CPS ≥1 tumors, the confirmed ORR was 11.1%, median OS was 12.7 months (4.5 to not reached), and median PFS was 2.2 months (1.8-4.2 months) with favezelimab plus pembrolizumab. CONCLUSIONS: Favezelimab with or without pembrolizumab had a manageable safety profile, with no treatment-related deaths. Promising antitumor activity was observed with combination therapy, particularly in participants with PD-L1 CPS ≥1 tumors.

Treatment with a retinoic acid-inducible gene I (RIG-I) agonist as monotherapy and in combination with pembrolizumab in patients with advanced solid tumors: results from two phase 1 studies.

BACKGROUND: We evaluated MK-4621, an oligonucleotide that binds and activates retinoic acid-inducible gene I (RIG-I), as monotherapy (NCT03065023) and in combination with the anti-programmed death 1 antibody pembrolizumab (NCT03739138). PATIENTS AND METHODS: Patients were ≥ 18 years with histologically/cytologically confirmed advanced/metastatic solid tumors with injectable lesions. MK-4621 (0.2‒0.8 mg) was administered intratumorally as a stable formulation with jetPEI™ twice weekly over a 4-week cycle as monotherapy and weekly in 3-week cycles for up to 6 cycles in combination with 200 mg pembrolizumab every 3 weeks for up to 35 cycles. Primary endpoints were dose-limiting toxicities (DLTs), treatment-related adverse events (AEs), and treatment discontinuation due to AEs. RESULTS: Fifteen patients received MK-4621 monotherapy and 30 received MK-4621 plus pembrolizumab. The only DLT, grade 3 pleural effusion that subsequently resolved, occurred in a patient who received MK-4621/jetPEI™ 0.8 mg plus pembrolizumab. 93% of patients experienced ≥ 1 treatment-related AE with both monotherapy and combination therapy. No patients experienced an objective response per RECIST v1.1 with MK-4621 monotherapy; 4 (27%) had stable disease. Three (10%) patients who received combination therapy had a partial response. Serum and tumor biomarker analyses provided evidence that MK-4621 treatment induced an increase in gene expression of interferon signaling pathway members and associated chemokines and cytokines. CONCLUSIONS: Patients treated with MK-4621 monotherapy or in combination with pembrolizumab experienced tolerable safety and modest antitumor activity, and there was evidence that MK-4621 activated the RIG-I pathway. At the doses tested, MK-4621 did not confer meaningful clinical benefit. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03065023 and NCT03739138.

Treatment outcome of atypical EGFR mutations in the German National Network Genomic Medicine Lung Cancer (nNGM).

BACKGROUND: Atypical EGFR mutations occur in 10%-30% of non-small-cell lung cancer (NSCLC) patients with EGFR mutations and their sensitivity to classical epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) is highly heterogeneous. Patients harboring one group of uncommon, recurrent EGFR mutations (G719X, S768I, L861Q) respond to EGFR-TKI. Exon 20 insertions are mostly insensitive to EGFR-TKI but display sensitivity to exon 20 inhibitors. Clinical outcome data of patients with very rare point and compound mutations upon systemic treatments are still sparse to date. PATIENTS AND METHODS: In this retrospective, multicenter study of the national Network Genomic Medicine (nNGM) in Germany, 856 NSCLC cases with atypical EGFR mutations including co-occurring mutations were reported from 12 centers. Clinical follow-up data after treatment with different EGFR-TKIs, chemotherapy and immune checkpoint inhibitors were available from 260 patients. Response to treatment was analyzed in three major groups: (i) uncommon mutations (G719X, S7681, L861Q and combinations), (ii) exon 20 insertions and (iii) very rare EGFR mutations (very rare single point mutations, compound mutations, exon 18 deletions, exon 19 insertions). RESULTS: Our study comprises the largest thus far reported real-world cohort of very rare EGFR single point and compound mutations treated with different systemic treatments. We validated higher efficacy of EGFR-TKI in comparison to chemotherapy in group 1 (uncommon), while most exon 20 insertions (group 2) were not EGFR-TKI responsive. In addition, we found TKI sensitivity of very rare point mutations (group 3) and of complex EGFR mutations containing exon 19 deletions or L858R mutations independent of the combination partner. Notably, treatment responses in group 3 (very rare) were highly heterogeneous. Co-occurring TP53 mutations exerted a non-significant trend for a detrimental effect on outcome in EGFR-TKI-treated patients in groups 2 and 3 but not in group 1. CONCLUSIONS: Based on our findings, we propose a novel nNGM classification of atypical EGFR mutations.

Risk stratification of EGFR+ lung cancer diagnosed with panel-based next-generation sequencing.

OBJECTIVE: Panel-based next-generation sequencing (NGS) is increasingly used for the diagnosis of EGFR-mutated non-small-cell lung cancer (NSCLC) and could improve risk assessment in combination with clinical parameters. MATERIALS AND METHODS: To this end, we retrospectively analyzed the outcome of 400 tyrosine kinase inhibitor (TKI)-treated EGFR+ NSCLC patients with validation of results in an independent cohort (n = 130). RESULTS: EGFR alterations other than exon 19 deletions (non-del19), TP53 co-mutations, and brain metastases at baseline showed independent associations of similar strengths with progression-free (PFS hazard ratios [HR] 2.1-2.3) and overall survival (OS HR 1.7-2.2), in combination defining patient subgroups with distinct outcome (EGFR+NSCLC risk Score, "ENS", p < 0.001). Co-mutations beyond TP53 were rarely detected by our multigene panel (<5%) and not associated with clinical endpoints. Smoking did not affect outcome independently, but was associated with non-del19 EGFR mutations (p < 0.05) and comorbidities (p < 0.001). Laboratory parameters, like the blood lymphocyte-to-neutrophil ratio and serum LDH, correlated with the metastatic pattern (p < 0.01), but had no independent prognostic value. Reduced ECOG performance status (PS) was associated with comorbidities (p < 0.05) and shorter OS (p < 0.05), but preserved TKI efficacy. Non-adenocarcinoma histology was also associated with shorter OS (p < 0.05), but rare (2-3 %). The ECOG PS and non-adenocarcinoma histology could not be validated in our independent cohort, and did not increase the range of prognostication alongside the ENS. CONCLUSIONS: EGFR variant, TP53 status and brain metastases predict TKI efficacy and survival in EGFR+ NSCLC irrespective of other currently available parameters ("ENS"). Together, they constitute a practical and reproducible approach for risk stratification of newly diagnosed metastatic EGFR+ NSCLC.

Distribution and levels of cell surface expression of CD33 and CD123 in acute myeloid leukemia.

Owing to the more recent positive results with the anti-CD33 immunotoxin gemtuzumab ozogamicin, therapy against acute myeloid leukemias (AMLs) targeting CD33 holds many promises. Here, CD33 and CD123 expression on AML blasts was studied by flow cytometry in a cohort of 319 patients with detailed information on French-American-British/World Health Organization (FAB/WHO) classification, cytogenetics and molecular aberrations. AMLs of 87.8% express CD33 and would therefore be targetable with anti-CD33 therapies. Additionally, 9.4% of AMLs express CD123 without concomitant CD33 expression. Thus, nearly all AMLs could be either targeted via CD33 or CD123. Simultaneous presence of both antigens was observed in 69.5% of patients. Most importantly, even AMLs with adverse cytogenetics express CD33 and CD123 levels comparable to those with favorable and intermediate subtypes. Some patient groups with unfavorable alterations, such as FMS-related tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutations, high FLT3-ITD mutant/wild-type ratios and monosomy 5 are even characterized by high expression of CD33 and CD123. In addition, blasts of patients with mutant nucleophosmin (NPM1) revealed significantly higher CD33 and CD123 expression pointing toward the possibility of minimal residual disease-guided interventions in mutated NPM1-positive AMLs. These results stimulate the development of novel concepts to redirect immune effector cells toward CD33- and CD123-expressing blasts using bi-specific antibodies or engineered T cells expressing chimeric antigen receptors.

Comparing propofol versus sevoflurane anesthesia for epileptogenic focus detection during positron emission tomography in pediatric patients.

BACKGROUND: Fluoro-D-deoxyglucose positron emission tomography (FDG-PET) is a standard procedure for interictal assessment and accurate pre-surgical evaluation of presumed epileptogenic zone localization. Profound sedation or general anesthesia is frequently required to reduce movement artefacts in young or cognitively impaired patients during image acquisition. This study compares the impact of propofol and sevoflurane anesthesia on overall quality of PET images, detectability of a hypometabolic lesion and demarcation of the detected lesion in pediatric patients suffering from focal epilepsia. METHODS: Pediatric patients with focal epilepsia were anesthesized using propofol (N.=37) or sevoflurane (N.=43). Two independent blinded investigators rated the PET-scans on a 3-point Likert scale with respect to overall quality of PET images, detectability of a hypometabolic lesion and demarcation of the detected lesion. Mann-Whitney-U-Test was conducted to compare the rating results between the two anesthesia regimes. Inter-rater reliability was calculated using Cohen's Kappa. RESULTS: Anesthesia was throughout uneventful and there was no clinical evidence for peridiagnostic seizures. Differences in neither single dimension ratings nor in sum scores (mean 5.8 ± SD 1.5 for propofol, and 5.7 ± SD 1.5 for sevoflurane; P=0.567) were statistically significant. Cohen's Kappa was between 0.428 and 0.499. CONCLUSION: For surgical planning in patients with epilepsy, FDG-PET imaging is an indispensable functional imaging technique to detect hypometabolism. We conclude that both, sevoflurane and propofol based anesthetic regimes are suitable to detect hypometabolic cerebral lesions during FDG-PET.

Respiratory failure in patients undergoing allogeneic hematopoietic SCT--a randomized trial on early non-invasive ventilation based on standard care hematology wards.

The prognosis of patients suffering from respiratory failure (RF) after allogeneic hematopoietic SCT (HSCT) is poor. However, early treatment for using non-invasive ventilation (NIV) may be of benefit. We conducted a randomized trial to prove the impact of early NIV in patients in the early post-transplant period. A total of 526 patients undergoing HSCT in a single center were monitored for signs of RF. Patients with RF were enrolled into either treatment arm A (oxygen supply only) or treatment arm B (oxygen+intermittent NIV). RF had to be diagnosed in 86 patients (16%). RF was an independent risk factor for both short-term (100 day mortality/ OR 2.76; P<0.001) and long-term survival (OR 1.57; P<0.01). Although early RF treatment with NIV was associated with a decreased rate of failure to achieve sufficient oxygenation (39% in arm A vs 24% in arm B, P=0.17), neither intensive care unit admission rate, nor need for intubation or survival parameters were affected by the treatment strategy. An early interventional strategy using NIV was not associated with improvement of the prognosis of the patients. The limited influence of NIV may be related to the study design allowing for switching of treatment in case of unsatisfactory efficacy.

Azacitidine for treatment of imminent relapse in MDS or AML patients after allogeneic HSCT: results of the RELAZA trial.

This study evaluated azacitidine as treatment of minimal residual disease (MRD) determined by a sensitive donor chimerism analysis of CD34(+) blood cells to pre-empt relapse in patients with CD34(+) myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (HSCT). At a median of 169 days after HSCT, 20/59 prospectively screened patients experienced a decrease of CD34(+) donor chimerism to <80% and received four azacitidine cycles (75 mg/m(2)/day for 7 days) while in complete hematologic remission. A total of 16 patients (80%) responded with either increasing CD34(+) donor chimerism to ≥80% (n=10; 50%) or stabilization (n=6; 30%) in the absence of relapse. Stabilized patients and those with a later drop of CD34(+) donor chimerism to <80% after initial response were eligible for subsequent azacitidine cycles. A total of 11 patients (55%) received a median of 4 (range, 1-11) additional cycles. Eventually, hematologic relapse occurred in 13 patients (65%), but was delayed until a median of 231 days (range, 56-558) after initial decrease of CD34(+) donor chimerism to <80%. In conclusion, pre-emptive azacitidine treatment has an acceptable safety profile and can substantially prevent or delay hematologic relapse in patients with MDS or AML and MRD after allogeneic HSCT.