HERTHENA-Lung02: phase III study of patritumab deruxtecan in advanced EGFR-mutated NSCLC after a third-generation EGFR TKI.

After disease progression on EGFR tyrosine kinase inhibitor (TKI) therapy, patients with EGFR-mutated NSCLC who are then treated with platinum-based chemotherapy (PBC) obtain only limited clinical benefit with transient responses. Therapies with greater efficacy and tolerable safety profiles are needed in this setting. The receptor tyrosine kinase HER3 is widely expressed in NSCLC, and increased expression is associated with poor treatment outcomes. In the U31402-A-U102 phase I trial, HER3-DXd showed promising antitumor activity with manageable safety in heavily pre-treated patients with EGFR-mutated NSCLC across a range of tumor HER3 expression levels and EGFR TKI resistance mechanisms. HERTHENA-Lung02 is the first phase III trial to evaluate the safety and efficacy of HER3-DXd versus PBC in patients with progression on a third-generation EGFR TKI. Clinical Trial Registration: NCT05338970 (clinicaltrials.gov); 2021-005879-40 (EudraCT Number).

In some patients with non-small-cell lung cancer, changes (or mutations) in the DNA sequence can alter a protein called EGFR and allow tumors to grow and survive. Drugs called EGFR tyrosine kinase inhibitors (EGFR TKIs for short) are used to treat these tumors by interfering with the abnormal EGFR protein. Treatment with these drugs can work well at first, but some tumors never respond, and for tumors that do respond, the cancer eventually becomes resistant to the EGFR TKI and the drug stops working. Platinum-based chemotherapy is often prescribed after an EGFR TKI stops working; however, platinum-based chemotherapy can provide only temporary control of the tumor growth. Most patients with non-small-cell lung cancer have a protein called HER3 on the surface of their tumor cells. A new drug candidate called patritumab deruxtecan (HER3-DXd) finds tumor cells and attaches to the HER3 protein on their surface. HER3-DXd then moves inside the cancer cells, where a novel antitumor payload is released and kills the tumor cells. This article describes the phase III clinical trial HERTHENA-Lung02 (NCT05338970) that compares the benefit of HER3-DXd to platinum-based chemotherapy for patients who have non-small-cell lung cancer with the abnormal EGFR protein and whose disease stopped responding or never responded to EGFR TKI therapy.

HERTHENA-Lung01: a phase II study of patritumab deruxtecan (HER3-DXd) in previously treated metastatic EGFR-mutated NSCLC.

Limited treatment options exist for EGFR-mutated NSCLC that has progressed after EGFR TKI and platinum-based chemotherapy. HER3 is highly expressed in EGFR-mutated NSCLC, and its expression is associated with poor prognosis in some patients. Patritumab deruxtecan (HER3-DXd) is an investigational, potential first-in-class, HER3-directed antibody-drug conjugate consisting of a HER3 antibody attached to a topoisomerase I inhibitor payload via a tetrapeptide-based cleavable linker. In an ongoing phase I study, HER3-DXd demonstrated promising antitumor activity and a tolerable safety profile in patients with EGFR-mutated NSCLC, with or without identified EGFR TKI resistance mechanisms, providing proof of concept of HER3-DXd. HERTHENA-Lung01 is a global, registrational, phase II trial further evaluating HER3-DXd in previously treated advanced EGFR-mutated NSCLC. Clinical Trial Registration: NCT04619004 (ClinicalTrials.gov); 2020-000730-17 (EudraCT).

This article describes a clinical trial of a new drug to treat non-small-cell lung cancer. About a third of patients with non-small-cell lung cancer have tumors with changes (mutations) in a gene called EGFR, which cause tumors to grow. These patients are treated with EGFR inhibitors and chemotherapy, both of which can stop the tumor from growing for a period of time. When these treatments stop working, new and effective treatments are needed. Most non-small-cell lung cancer tumors have a protein called HER3 on the surface of their cells. Patritumab deruxtecan (HER3-DXd) is a new drug candidate that uses HER3 to get chemotherapy inside tumor cells. In an earlier clinical trial for patients with lung cancer whose disease had grown after multiple treatments, HER3-DXd often shrank tumors or stopped them from growing. The side effects of HER3-DXd were tolerable. The clinical trial described in this publication, HERTHENA-Lung01 (NCT04619004), is testing HER3-DXd in a larger group of patients with non-small-cell lung cancer that has activating mutations in the EGFR gene and for whom previous treatments have stopped working. The results of this study will help doctors and regulators decide if HER3-DXd should be approved and used for patients with non-small-cell lung cancer with EGFR mutations.

Implementing a low-threshold audio-only telehealth model for medication-assisted treatment of opioid use disorder at a community-based non-profit organization in Washington, D.C.

BACKGROUND: The COVID-19 pandemic has had especially devastating effects on people who use drugs. Due to pandemic protocols in the USA, medication-assisted treatment (MAT) regulations became more flexible, permitting our community-based nonprofit organization to transition its low-threshold MAT clinic to an audio-only telehealth model of care in 2020. Lessons learned have the potential to improve MAT delivery to people with OUD. CASE PRESENTATION: This case study describes our transition from a low-threshold community-based in-person MAT clinic to an audio-only telehealth model. We extracted data from electronic health records to describe patient characteristics and to calculate treatment retention rates. Patients were predominantly male (74.4%) and black (90.6%). The mean age was 53 years old with more than half of the clients aged 55 or older. Less than half (42.3%) of the patients lived in stable housing. Patients commonly had self-reported comorbid conditions such as hypertension (35.4%), hepatitis C (23.5%), diabetes (11.9%), human immunodeficiency virus (HIV) (7.2%). A majority of patients (68.6%) reported engagement with behavioral health care. We measure the success of our intervention relative to published retention rates, both overall as well as for in-person and telehealth care. In-person retention rates at 90- and 180-days were substantially higher than telehealth retention rates (93.9% vs 68.4% and 91.5% vs 51.9%, respectively). CONCLUSIONS: Low-threshold medication-assisted treatment in the care of people with opioid use disorder is essential to increasing treatment access and continuity. We found that an audio-only telehealth model was viable. Although we had decreased retention rates following the transition to an audio-only telehealth model, our rates remained excellent compared to published values for in-person MAT care. We call for advocacy and regulations to support continued use of telehealth services throughout and beyond the COVID-19 pandemic.

Concurrent Initiation of Hepatitis C and Opioid Use Disorder Treatment in People Who Inject Drugs.

BACKGROUND: People who inject drugs have a high prevalence of hepatitis C virus (HCV) and significant disease associated with drug use; however, HCV treatment often occurs in absence of interventions to address opioid use disorder and drug use-related harms. The impact of concurrent initiation of opioid agonist therapy (OAT) on HCV treatment and drug use outcomes is unknown. METHODS: In this prospective, open-label, observational trial at a harm reduction organization's drop-in center in Washington, DC, 100 patients with chronic HCV infection, opioid use disorder, and ongoing injection drug use were treated with sofosbuvir-velpatasvir for 12-weeks and offered buprenorphine initiation. The primary end point was sustained virologic response (SVR), and secondary end points included uptake of and retention in OAT, change in risk behavior, and determinants of SVR. RESULTS: Eighty-two patients (82%) achieved SVR, which was not associated with baseline OAT status (P = .33), on-treatment drug use (P >.99), or imperfect daily adherence (P = .35) but was significantly associated with completing 2 or more 28-pill bottles of sofosbuvir-velpatasvir (P < .001) and receiving OAT at week 24 (P = .01). Of 67 patients not already receiving OAT at baseline, 53 (79%) started OAT. At week 24, 68 (68%) patients were receiving OAT. Receipt of OAT was associated with fewer opiate-positive urine drug screens (P = .003), lower human immunodeficiency virus risk-taking behavior scores (P < .001), and lower rates of opioid overdose (P = .04). CONCLUSIONS: The Novel Model of Hepatitis C Treatment as an Anchor to Prevent HIV, Initiate Opioid Agonist Therapy, and Reduce Risky Behavior study demonstrates high uptake of buprenorphine collocated with HCV treatment, and it shows that concurrent initiation of OAT with HCV treatment can result in high rates of SVR while reducing risks associated with drug use. CLINICAL TRIALS REGISTRATION: NCT03221309.

Efficacy and Safety of Midostaurin in Advanced Systemic Mastocytosis.

BACKGROUND: Advanced systemic mastocytosis comprises rare hematologic neoplasms that are associated with a poor prognosis and lack effective treatment options. The multikinase inhibitor midostaurin inhibits KIT D816V, a primary driver of disease pathogenesis. METHODS: We conducted an open-label study of oral midostaurin at a dose of 100 mg twice daily in 116 patients, of whom 89 with mastocytosis-related organ damage were eligible for inclusion in the primary efficacy population; 16 had aggressive systemic mastocytosis, 57 had systemic mastocytosis with an associated hematologic neoplasm, and 16 had mast-cell leukemia. The primary outcome was the best overall response. RESULTS: The overall response rate was 60% (95% confidence interval [CI], 49 to 70); 45% of the patients had a major response, which was defined as complete resolution of at least one type of mastocytosis-related organ damage. Response rates were similar regardless of the subtype of advanced systemic mastocytosis, KIT mutation status, or exposure to previous therapy. The median best percentage changes in bone marrow mast-cell burden and serum tryptase level were -59% and -58%, respectively. The median overall survival was 28.7 months, and the median progression-free survival was 14.1 months. Among the 16 patients with mast-cell leukemia, the median overall survival was 9.4 months (95% CI, 7.5 to not estimated). Dose reduction owing to toxic effects occurred in 56% of the patients; re-escalation to the starting dose was feasible in 32% of those patients. The most frequent adverse events were low-grade nausea, vomiting, and diarrhea. New or worsening grade 3 or 4 neutropenia, anemia, and thrombocytopenia occurred in 24%, 41%, and 29% of the patients, respectively, mostly in those with preexisting cytopenias. CONCLUSIONS: In this open-label study, midostaurin showed efficacy in patients with advanced systemic mastocytosis, including the highly fatal variant mast-cell leukemia. (Funded by Novartis Pharmaceuticals and others; ClinicalTrials.gov number, NCT00782067.).

Can species traits predict the susceptibility of riverine fish to water resource development? An Australian case study.

Water resource developments alter riverine environments by disrupting longitudinal connectivity, transforming lotic habitats, and modifying in-stream hydraulic conditions. Effective management of anthropogenic disturbances therefore requires an understanding of the range of potential ecosystem effects and the inherent traits symptomatic of elevated vulnerability to disturbance. Using 42 riverine fish native to South Eastern Australia as a case study, we quantified six morphological, behavioral, and life-history traits to classify species into groups reflecting potential differences in their response to ecosystem changes as a result of water resource development. Classification analysis identified five strategies based on fish life-history dispersal requirements, climbing potential, and habitat preference. These strategies in turn highlight the potential species at risk from the separate impacts of water resource development and inform management decisions to mitigate those risks. Swimming ability did not contribute to distinguishing species into functional groups, likely due to methodological inconsistencies in quantifying swimming performance that may ultimately hinder the ability of fish passage facilities to function within the physical capabilities of species at risk of habitat fragmentation. This study improves our ability to predict the performance of groups of species at risk from the multiple environmental changes imposed by humans and goes beyond broad-scale dispersal requirements as a predictor of individual species response.

Real-World Treatment Patterns and Clinical Outcomes Among Patients with Metastatic or Unresectable EGFR-Mutated Non-Small Cell Lung Cancer Previously Treated with Osimertinib and Platinum-Based Chemotherapy.

INTRODUCTION: For patients with epidermal growth factor receptor-mutated (EGFRm) locally advanced/metastatic non-small cell lung cancer (mNSCLC) whose disease has progressed on or after osimertinib and platinum-based chemotherapy (PBC), no uniformly accepted standard of care exists. Moreover, limited efficacy of standard treatments indicates an unmet medical need, which is being addressed by ongoing clinical investigations, including the HERTHENA-Lung01 (NCT04619004) study of patritumab deruxtecan (HER3­DXd). However, because limited information is available on real-world clinical outcomes in such patients, early-phase trials of investigational therapies lack sufficient context for comparison. This study describes the real-world clinical characteristics, treatments, and outcomes for patients with EGFRm mNSCLC who initiated a new line of therapy following previous osimertinib and PBC, including a subset matched to the HERTHENA-Lung01 population. METHODS: This retrospective analysis used a US database derived from deidentified electronic health records. The reference cohort included patients with EGFRm mNSCLC who had initiated a new line of therapy between November 13, 2015 and June 30, 2021, following prior osimertinib and PBC. A subset of patients resembling the HERTHENA-Lung01 population was then extracted from the reference cohort; this matched subset was optimized using propensity score (PS) weighting. Endpoints were real-world overall survival (rwOS) and real-world progression-free survival (rwPFS). Confirmed real-world objective response rate (rwORR; partial/complete response confirmed ≥ 28 days later) was calculated for the response-evaluable subgroups of patients (with ≥ 2 response assessments spaced ≥ 28 days apart). RESULTS: In the reference cohort (N = 273), multiple treatment regimens were used, and none was predominant. Median rwPFS and rwOS were 3.3 and 8.6 months, respectively; confirmed rwORR (response evaluable, n = 123) was 13.0%. In the matched subset (n = 126), after PS weighting, median rwPFS and rwOS were 4.2 and 9.1 months, respectively; confirmed rwORR (response evaluable, n = 57) was 14.1%. CONCLUSION: The treatment landscape for this heavily pretreated population of patients with EGFRm mNSCLC is fragmented, with no uniformly accepted standard of care. A high unmet need exists for therapeutic options that provide meaningful improvements in clinical benefit.

Patritumab Deruxtecan (HER3-DXd), a Human Epidermal Growth Factor Receptor 3-Directed Antibody-Drug Conjugate, in Patients With Previously Treated Human Epidermal Growth Factor Receptor 3-Expressing Metastatic Breast Cancer: A Multicenter, Phase I/II Trial.

PURPOSE: Human epidermal growth factor receptor 3 (HER3) is broadly expressed in breast cancer; high expression is associated with an adverse prognosis. Patritumab deruxtecan (HER3-DXd) is an investigational HER3-targeted antibody-drug conjugate that is being evaluated as a novel treatment in HER3-expressing advanced breast cancer in the U31402-A-J101 study. METHODS: Adults with disease progression on previous therapies were eligible. Patients in the dose-escalation, dose-finding, and dose-expansion parts received HER3-DXd 1.6-8.0 mg/kg intravenously once every 3 weeks or one of two alternative dosing regimens. In the dose-escalation part, the primary objectives were to determine the maximum tolerated dose and recommended dose for expansion (RDE). The safety and efficacy of the RDE were assessed during dose expansion. RESULTS: One hundred eighty-two enrolled patients received ≥1 dose of HER3-DXd. Patients had a median of five previous therapies for advanced disease. Efficacy results are reported across clinical subtypes: hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-negative) breast cancer (n = 113; objective response rate [ORR], 30.1%; median progression-free survival [mPFS], 7.4 months), triple-negative breast cancer (n = 53; ORR, 22.6%; mPFS, 5.5 months), and HER2-positive breast cancer (n = 14; ORR, 42.9%; mPFS, 11.0 months). Objective responses were observed in cancers with HER3-high and HER3-low membrane expression. Dose-limiting toxicities observed during dose selection were decreased platelet count and elevated aminotransferases. In dose expansion, GI and hematologic toxicities were the most common treatment-emergent adverse events (TEAEs) observed. Grade ≥3 TEAEs were observed in 71.4% of patients, and 9.9% discontinued treatment because of TEAEs. Three grade 3 and one grade 5 treatment-related interstitial lung disease events occurred. CONCLUSION: HER3-DXd demonstrated a manageable safety profile and durable efficacy in heavily pretreated patients across clinical subtypes. These data warrant further evaluation of HER3-DXd in patients with HER3-expressing metastatic breast cancer.

HERTHENA-Lung01, a Phase II Trial of Patritumab Deruxtecan (HER3-DXd) in Epidermal Growth Factor Receptor-Mutated Non-Small-Cell Lung Cancer After Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Therapy and Platinum-Based Chemotherapy.

PURPOSE: Patritumab deruxtecan, or HER3-DXd, is an antibody-drug conjugate consisting of a fully human monoclonal antibody to human epidermal growth factor receptor 3 (HER3) attached to a topoisomerase I inhibitor payload via a stable tetrapeptide-based cleavable linker. We assessed the efficacy and safety of HER3-DXd in patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC). METHODS: This phase II study (ClinicalTrials.gov identifier: NCT04619004) was designed to evaluate HER3-DXd in patients with advanced EGFR-mutated NSCLC previously treated with EGFR tyrosine kinase inhibitor (TKI) therapy and platinum-based chemotherapy (PBC). Patients received HER3-DXd 5.6 mg/kg intravenously once every 3 weeks or an uptitration regimen (3.2 → 4.8 → 6.4 mg/kg). The primary end point was confirmed objective response rate (ORR; RECIST 1.1) by blinded independent central review (BICR), with a null hypothesis of 26.4% on the basis of historical data. RESULTS: Enrollment into the uptitration arm closed early on the basis of a prespecified benefit-risk assessment of data from the phase I U31402-A-U102 trial. In total, 225 patients received HER3-DXd 5.6 mg/kg once every 3 weeks. As of May 18, 2023, median study duration was 18.9 (range, 14.9-27.5) months. Confirmed ORR by BICR was 29.8% (95% CI, 23.9 to 36.2); median duration of response, 6.4 months; median progression-free survival, 5.5 months; and median overall survival, 11.9 months. The subgroup of patients with previous osimertinib and PBC had similar outcomes. Efficacy was observed across a broad range of pretreatment tumor HER3 membrane expression levels and across diverse mechanisms of EGFR TKI resistance. In patients with nonirradiated brain metastases at baseline (n = 30), the confirmed CNS ORR by BICR per CNS RECIST was 33.3% (95% CI, 17.3 to 52.8). The safety profile (National Cancer Institute Common Terminology Criteria for Adverse Events v5.0) was manageable and tolerable, consistent with previous observations. CONCLUSION: After tumor progression with EGFR TKI therapy and PBC in patients with EGFR-mutated NSCLC, HER3-DXd once every 3 weeks demonstrated clinically meaningful efficacy with durable responses, including in CNS metastases. A phase III trial in EGFR-mutated NSCLC after progression on an EGFR TKI is ongoing (HERTHENA-Lung02; ClinicalTrials.gov identifier: NCT05338970).

Block of C/EBP alpha function by phosphorylation in acute myeloid leukemia with FLT3 activating mutations.

Mutations constitutively activating FLT3 kinase are detected in approximately 30% of acute myelogenous leukemia (AML) patients and affect downstream pathways such as extracellular signal-regulated kinase (ERK)1/2. We found that activation of FLT3 in human AML inhibits CCAAT/enhancer binding protein alpha (C/EBPalpha) function by ERK1/2-mediated phosphorylation, which may explain the differentiation block of leukemic blasts. In MV4;11 cells, pharmacological inhibition of either FLT3 or MEK1 leads to granulocytic differentiation. Differentiation of MV4;11 cells was also observed when C/EBPalpha mutated at serine 21 to alanine (S21A) was stably expressed. In contrast, there was no effect when serine 21 was mutated to aspartate (S21D), which mimics phosphorylation of C/EBPalpha. Thus, our results suggest that therapies targeting the MEK/ERK cascade or development of protein therapies based on transduction of constitutively active C/EBPalpha may prove effective in treatment of FLT3 mutant leukemias resistant to the FLT3 inhibitor therapies.

PrEP Indications and PrEP Knowledge, Access, and Interest Among Individuals With HCV.

Background: Individuals with hepatitis C (HCV) represent a population that may benefit from pre-exposure prophylaxis (PrEP), given the overlapping risk factors and transmission networks of HCV and HIV. This analysis assesses the prevalence of PrEP indications among individuals with HCV monoinfection and PrEP awareness, interest, and access in this population. Methods: GRAVITY was an observational study for the collection of epidemiologic data from individuals with HCV and/or HIV in Washington DC and Baltimore, with the present analysis limited to HCV-monoinfected patients. The prevalence of PrEP indications was determined using epidemiologic survey responses. Bivariate and multivariable analyses assessed for associations between PrEP indications and PrEP awareness, access, and interest. Results: Among 314 HCV-monoinfected participants, 109 (35%) had an indication for PrEP. Forty-eight (44%) had a drug use indication alone, 40 (37%) had a sexual indication alone, and 21 (19%) had both drug use and sexual indications. Eighty-five (27%) participants had heard of PrEP, 32 (10%) had been offered PrEP by a provider, 114 (38%) were interested or maybe interested in PrEP, and 6 (2%) were currently taking PrEP. On bivariate analysis, PrEP awareness was significantly associated with study site (P < .0001), race (P = .0003), age (P < .0001), and sexual PrEP indication (P = .04). However, only study site remained significant (P = .0002) on regression analysis. Conclusions: Though indications for PrEP were prevalent among individuals with HCV in this cohort, most patients were unaware of PrEP, had never been offered PrEP, and were not using PrEP. These data support the need for improved PrEP implementation among people with HCV.

Initiation of Low-threshold Buprenorphine in Nontreatment Seeking Patients With Opioid Use Disorder Engaged in Hepatitis C Treatment.

OBJECTIVE: The ANCHOR program offered buprenorphine treatment to people who inject drugs engaged in hepatitis C (HCV) treatment at a Washington, DC harm reduction organization. This analysis describes the program model and outcomes of the opioid care continuum at 1 year. METHODS: Primary outcomes were initiation of buprenorphine and retention in care, defined by an active buprenorphine prescription at given time points. Secondary outcomes included treatment interruptions, reasons for treatment noninitiation and termination, buprenorphine and opiate use, and HIV risk behaviors. Buprenorphine and opiate use were measured by urine toxicology screens and HIV risk behavior was quantified using a validated survey. RESULTS: Of 67 patients receiving HCV treatment not on opioid agonist therapy at baseline, 96% (n = 64) were interested and 73% (n = 49) initiated buprenorphine. Retention was 82% (n = 40), 65% (n = 32), and 59% (n = 29) at months 1, 6, and 12, respectively. Retention at 12 months was associated with self-reported engagement in routine medical care (P < 0.01), but was not associated with gender, stable housing, past opioid agonist therapy, or past overdose. Among retained patients, urine screens positive for opioids were 73% (n = 29), 56% (n = 18), and 79% (n = 23) at months 1, 6, and 12. There was a significant mean decrease in HIV risk-taking behavior scores over the treatment period, primarily driven by reduced injection frequency. CONCLUSIONS: Patients engaged in HCV treatment at a harm reduction organization showed a high rate of initiation of buprenorphine treatment, with retention comparable to other treatment settings. Although most patients continued using opioids on treatment, there was a reduced frequency of injection drug use, a significant driver of OUD-related risk. These data support the use of low-threshold buprenorphine access alongside HCV treatment to reduce morbidity and mortality in people with OUD.

Suboptimal Uptake, Retention, and Adherence of Daily Oral Prexposure Prophylaxis Among People With Opioid Use Disorder Receiving Hepatitis C Virus Treatment.

BACKGROUND: Daily oral preexposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) prevents human immunodeficiency (HIV) among people who inject drugs (PWID). Despite rising HIV incidence and injection drug use (IDU), PrEP use remains low and there is limited research about uptake, adherence, and retention among PWID. METHODS: The ANCHOR investigation evaluated a community-based care model collocating hepatitis C virus (HCV) treatment, medication for opioid use disorder (OUD), and PrEP in individuals in Washington, DC, and Baltimore, Maryland. PrEP counseling was conducted from HCV treatment day 0 until week 24. Subjects could start any time during this window, were followed for 48 weeks, and were assessed for adherence by self-report and dried blood spot TDF analysis. RESULTS: One hundred ninety-eight participants were enrolled, of whom 185 (93%) were HIV negative. Twenty-nine individuals (15.7% of HIV-negative cohort) initiated PrEP. One hundred sixteen participants (62.7%) met 2014 Centers for Disease Control and Prevention (CDC) PrEP criteria due to IDU (82 [44.3%]), sex (9 [4.9%]), or both practices (25 [13.5%]). Providers recommended PrEP to 94 individuals (50.8%), and recommendation was associated with PrEP uptake. Median treatment duration was 104 days (interquartile range, 28-276 days), with 8 participants retained through week 48. Adherence was variable over time by self-report and declined by TDF analysis. No HIV seroconversions occurred. CONCLUSIONS: This cohort of people with HCV and OUD experienced low uptake of PrEP despite the majority meeting CDC criteria. High rates of disruption and discontinuation, compounded by variable adherence, made TDF/FTC a suboptimal prevention strategy. Emerging modalities like long-acting formulations may address these barriers, but PWID have been excluded from their development to date.

Efficacy and Safety of Patritumab Deruxtecan (HER3-DXd) in EGFR Inhibitor-Resistant, EGFR-Mutated Non-Small Cell Lung Cancer.

Receptor tyrosine-protein kinase ERBB3 (HER3) is expressed in most EGFR-mutated lung cancers but is not a known mechanism of resistance to EGFR inhibitors. HER3-DXd is an antibody-drug conjugate consisting of a HER3 antibody attached to a topoisomerase I inhibitor payload via a tetrapeptide-based cleavable linker. This phase I, dose escalation/expansion study included patients with locally advanced or metastatic EGFR-mutated non-small cell lung cancer (NSCLC) with prior EGFR tyrosine kinase inhibitor (TKI) therapy. Among 57 patients receiving HER3-DXd 5.6 mg/kg intravenously once every 3 weeks, the confirmed objective response rate by blinded independent central review (Response Evaluation Criteria in Solid Tumors v1.1) was 39% [95% confidence interval (CI), 26.0-52.4], and median progression-free survival was 8.2 (95% CI, 4.4-8.3) months. Responses were observed in patients with known and unknown EGFR TKI resistance mechanisms. Clinical activity was observed across a broad range of HER3 membrane expression. The most common grade ≥3 treatment-emergent adverse events were hematologic toxicities. HER3-DXd has clinical activity in EGFR TKI-resistant cancers independent of resistance mechanisms, providing an approach to treat a broad range of drug-resistant cancers. SIGNIFICANCE: In metastatic EGFR-mutated NSCLC, after disease progression on EGFR TKI therapy, treatment approaches include genotype-directed therapy targeting a known resistance mechanism or chemotherapy. HER3-DXd demonstrated clinical activity spanning known and unknown EGFR TKI resistance mechanisms. HER3-DXd could present a future treatment option agnostic to the EGFR TKI resistance mechanism.See related commentary by Lim et al., p. 16.This article is highlighted in the In This Issue feature, p. 1.

Altered lymphocyte trafficking and diminished airway reactivity in transgenic mice expressing human MMP-9 in a mouse model of asthma.

Matrix metalloproteinase-9 (MMP-9) is hypothesized to facilitate leukocyte extravasation and extracellular remodeling in asthmatic airways. Careful descriptive studies have shown that MMP-9 levels are higher in the sputum of asthmatics; however, the consequence of increased MMP-9 activity has not been determined in this disease. We induced asthma in transgenic mice that express human MMP-9 in the murine lung tissue macrophage to determine the direct effect of human MMP-9 expression on airway inflammation. Transgenic (TG) and wild-type (WT) mice were immunized and challenged with ovalbumin. Forty-eight hours after the ovalbumin challenge, airway hyperresponsiveness (AHR) was measured, and inflammatory cell infiltration was evaluated in bronchoalveolar lavage fluid (BALF) and lung tissue. Baseline levels of inflammation were similar in the TG and WT groups of mice, and pulmonary eosinophilia was established in both groups by sensitization and challenge with ovalbumin. There was a significant reduction in AHR in sensitized and challenged trangenics compared with WT controls. Although total BALF cell counts were similar in both groups, the lymphocyte number in the lavage of the TG group was significantly diminished compared with the WT group (0.25 +/- 0.08 vs. 0.89 +/- 0.53; P = 0.0032). In addition, the draining lymphocytes were found to be larger in the TG animals compared with the WT mice. Equal numbers of macrophages, eosinophils, and neutrophils were seen in both groups. IL-13 levels were found to be lower in the sensitized TG compared with the WT mice. These results demonstrate an inverse relationship between human MMP-9 and AHR and suggest that MMP-9 expression alters leukocyte extravasation by reducing lymphocyte accumulation in the walls of asthmatic airways.

Eosinophil and T cell markers predict functional decline in COPD patients.

BACKGROUND: The major marker utilized to monitor COPD patients is forced expiratory volume in one second (FEV1). However, a single measurement of FEV1 cannot reliably predict subsequent decline. Recent studies indicate that T lymphocytes and eosinophils are important determinants of disease stability in COPD. We therefore measured cytokine levels in the lung lavage fluid and plasma of COPD patients in order to determine if the levels of T cell or eosinophil related cytokines were predictive of the future course of the disease. METHODS: Baseline lung lavage and plasma samples were collected from COPD subjects with moderately severe airway obstruction and emphysematous changes on chest CT. The study participants were former smokers who had not had a disease exacerbation within the past six months or used steroids within the past two months. Those subjects who demonstrated stable disease over the following six months (DeltaFEV1 % predicted = 4.7 +/- 7.2; N = 34) were retrospectively compared with study participants who experienced a rapid decline in lung function (DeltaFEV1 % predicted = -16.0 +/- 6.0; N = 16) during the same time period and with normal controls (N = 11). Plasma and lung lavage cytokines were measured from clinical samples using the Luminex multiplex kit which enabled the simultaneous measurement of several T cell and eosinophil related cytokines. RESULTS AND DISCUSSION: Stable COPD participants had significantly higher plasma IL-2 levels compared to participants with rapidly progressive COPD (p = 0.04). In contrast, plasma eotaxin-1 levels were significantly lower in stable COPD subjects compared to normal controls (p < 0.03). In addition, lung lavage eotaxin-1 levels were significantly higher in rapidly progressive COPD participants compared to both normal controls (p < 0.02) and stable COPD participants (p < 0.05). CONCLUSION: These findings indicate that IL-2 and eotaxin-1 levels may be important markers of disease stability in advanced emphysema patients. Prospective studies will need to confirm whether measuring IL-2 or eotaxin-1 can identify patients at risk for rapid disease progression.

Identification of the benign mesenchymal tumor gene HMGA2 in lymphangiomyomatosis.

The normal expression pattern of HMGA2, an architectural transcription factor, is primarily restricted to cells of the developing mesenchyme before their overt differentiation during organogenesis. A detailed in situ hybridization analysis showed that the undifferentiated mesoderm of the embryonic lung expressed Hmga2 but it was not expressed in the newborn or adult lung. Previously, HMGA2 was shown to be misexpressed in a number of benign, differentiated mesenchymal tumors including lipomas, uterine leiomyomas, and pulmonary chondroid hamartomas. Here, we show that HMGA2 is misexpressed in pulmonary lymphangiomyomatosis (LAM), a severe disorder of unknown etiology consisting of lymphatic smooth muscle cell proliferation that results in the obstruction of airways, lymphatics, and vessels. Immunohistochemistry was done with antibodies to HMGA2 and revealed expression in lung tissue samples obtained from 21 patients with LAM. In contrast, HMGA2 was not expressed in sections of normal adult lung or other proliferative interstitial lung diseases, indicating that the expression of HMGA2 in LAM represents aberrant gene activation and is not due solely to an increase in cellular proliferation. In vivo studies in transgenic mice show that misexpression of HMGA2 in smooth muscle cells resulted in increased proliferation of these cells in the lung surrounding the epithelial cells. Therefore, similar to the other mesenchymal neoplasms, HMGA2 misexpression in the smooth muscle cell leads to abnormal proliferation and LAM tumorigenesis. These results suggest that HMGA2 plays a central role in the pathogenesis of LAM and is a potential candidate as a therapeutic target.

THOC5 spliceosome protein: a target for leukaemogenic tyrosine kinases that affects inositol lipid turnover.

The fusion protein TEL/PDGFRB is associated with chronic myelomonocytic leukaemia and has intrinsic tyrosine kinase activity. The effects of TEL/PDGFRB were assessed using the multipotent haemopoietic cell line FDCP-Mix. In the absence of growth factors, TEL/PDGFRB expression increased survival that was associated with elevated levels of phosphatidylinositol 3,4,5 trisphosphate (PIP3). Whilst TEL/PDGFRB had subtle effects on the growth factor requirements it had a profound effect on differentiation. The cells became refractory to cytokine-stimulated development, showing limited maturation but failing to produce fully mature cells. We have previously identified the spliceosome protein THOC5 as a target in macrophage colony-stimulating factor signalling and a protein involved in the regulation of transcription factor expression. TEL/PDGFRB expression increased the expression and phosphorylation of THOC5. Elevated expression of THOC5 increased PIP3 levels and decreased apoptosis. Mass spectrometry was used to identify a site for TEL/PDGFRB-mediated phosphorylation on THOC5, which was shown to be a target for a number of other leukaemogenic tyrosine kinases. Thus, THOC5 is a novel target for modulation of signal transduction with a potential role in leukaemogenesis.

Parameterization of Fuel-Optimal Synchronous Approach Trajectories to Tumbling Targets.

Docking with potentially tumbling Targets is a common element of many mission architectures, including on-orbit servicing and active debris removal. This paper studies synchronized docking trajectories as a way to ensure the Chaser satellite remains on the docking axis of the tumbling Target, thereby reducing collision risks and enabling persistent onboard sensing of the docking location. Chaser satellites have limited computational power available to them and the time allowed for the determination of a fuel optimal trajectory may be limited. Consequently, parameterized trajectories that approximate the fuel optimal trajectory while following synchronous approaches may be used to provide a computationally efficient means of determining near optimal trajectories to a tumbling Target. This paper presents a method of balancing the computation cost with the added fuel expenditure required for parameterization, including the selection of a parameterization scheme, the number of parameters in the parameterization, and a means of incorporating the dynamics of a tumbling satellite into the parameterization process. Comparisons of the parameterized trajectories are made with the fuel optimal trajectory, which is computed through the numerical propagation of Euler's equations. Additionally, various tumble types are considered to demonstrate the efficacy of the presented computation scheme. With this parameterized trajectory determination method, Chaser satellites may perform terminal approach and docking maneuvers with both fuel and computational efficiency.

Surgical therapy of lung metastases.

Almost 125 years after the first documented case, pulmonary metastasectomy is still poorly understood. No other organ is subject to the wide histologic variety of metastatic insults, and this fact has complicated a complete exposition of when pulmonary metastasectomy may be beneficial. Many physicians still consider pulmonary metastatic disease to be always incurable, and they may underestimate existing surgical options including the benefits of pulmonary metastasectomy. In addition, technological improvements in radiological screening of pulmonary metastases and thoracoscopic resection are fundamentally altering the management of these patients and their surgery. This article reviews the history, form, and future of pulmonary metastasectomy, the literature that supports or refutes its application in various tumor types, and the screening and surgical evaluation that is needed prior to its performance.