Association of SARS-CoV-2 Infection and Cardiopulmonary Long COVID With Exercise Capacity and Chronotropic Incompetence Among People With HIV.

Background Postacute sequelae of COVID-19 (PASC) and HIV are both associated with reduced exercise capacity, but whether SARS-CoV-2 or PASC are associated with exercise capacity among people with HIV (PWH) is unknown. We hypothesized that PWH with PASC would have reduced exercise capacity from chronotropic incompetence. Methods and Results We conducted cross-sectional cardiopulmonary exercise testing within a COVID recovery cohort that included PWH with and without prior SARS-CoV-2 infection and people without HIV with prior SARS-CoV-2 infection (controls). We evaluated associations of HIV, SARS-CoV-2, and PASC with exercise capacity (peak oxygen consumption) and chronotropy (adjusted heart rate reserve). We included 83 participants (median age, 54 years; 35% women; 37 PWH): 23 out of 37 (62%) PWH and all 46 controls had prior SARS-CoV-2 infection, and 11 out of 23 (48%) PWH and 28 out of 46 (61%) without HIV had PASC. Peak oxygen consumption was reduced among PWH versus controls (80% predicted versus 99%, P=0.005), a difference of 5.5 mL/kg per minute (95% CI, 2.7-8.2; P<0.001). Chronotropic incompetence was more prevalent among PWH (38% versus 11%, P=0.002), with lower adjusted heart rate reserve (60% versus 83%, P<0.0001) versus controls. Among PWH, SARS-CoV-2 coinfection and PASC were not associated with exercise capacity. Chronotropic incompetence was more common among PWH with PASC: 7 out of 11 (64%) with PASC versus 7 out of 26 (27%) without PASC (P=0.04). Conclusions Exercise capacity and chronotropy are lower among PWH compared with individuals with SARS-CoV-2 infection without HIV. Among PWH, SARS-CoV-2 infection and PASC were not strongly associated with reduced exercise capacity. Chronotropic incompetence may be a common underrecognized mechanism of exercise intolerance among PWH, especially those with cardiopulmonary PASC.

Reduced Exercise Capacity, Chronotropic Incompetence, and Early Systemic Inflammation in Cardiopulmonary Phenotype Long Coronavirus Disease 2019.

BACKGROUND: Mechanisms underlying persistent cardiopulmonary symptoms after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (postacute sequelae of coronavirus disease 2019 [COVID-19; PASC] or "long COVID") remain unclear. This study sought to elucidate mechanisms of cardiopulmonary symptoms and reduced exercise capacity. METHODS: We conducted cardiopulmonary exercise testing (CPET), cardiac magnetic resonance imaging (CMR) and ambulatory rhythm monitoring among adults >1 year after SARS-CoV-2 infection, compared those with and those without symptoms, and correlated findings with previously measured biomarkers. RESULTS: Sixty participants (median age, 53 years; 42% female; 87% nonhospitalized; median 17.6 months after infection) were studied. At CPET, 18/37 (49%) with symptoms had reduced exercise capacity (<85% predicted), compared with 3/19 (16%) without symptoms (P = .02). The adjusted peak oxygen consumption (VO2) was 5.2 mL/kg/min lower (95% confidence interval, 2.1-8.3; P = .001) or 16.9% lower percent predicted (4.3%-29.6%; P = .02) among those with symptoms. Chronotropic incompetence was common. Inflammatory markers and antibody levels early in PASC were negatively correlated with peak VO2. Late-gadolinium enhancement on CMR and arrhythmias were absent. CONCLUSIONS: Cardiopulmonary symptoms >1 year after COVID-19 were associated with reduced exercise capacity, which was associated with earlier inflammatory markers. Chronotropic incompetence may explain exercise intolerance among some with "long COVID."

Reduced exercise capacity, chronotropic incompetence, and early systemic inflammation in cardiopulmonary phenotype Long COVID.

BACKGROUND: Mechanisms underlying persistent cardiopulmonary symptoms following SARS-CoV-2 infection (post-acute sequelae of COVID-19 "PASC" or "Long COVID") remain unclear. This study sought to elucidate mechanisms of cardiopulmonary symptoms and reduced exercise capacity using advanced cardiac testing. METHODS: We performed cardiopulmonary exercise testing (CPET), cardiac magnetic resonance imaging (CMR) and ambulatory rhythm monitoring among adults > 1 year after confirmed SARS-CoV-2 infection in Long-Term Impact of Infection with Novel Coronavirus cohort (LIINC; substudy of NCT04362150 ). Adults who completed a research echocardiogram (at a median 6 months after SARS-CoV-2 infection) without evidence of heart failure or pulmonary hypertension were asked to complete additional cardiopulmonary testing approximately 1 year later. Although participants were recruited as a prospective cohort, to account for selection bias, the primary analyses were as a case-control study comparing those with and without persistent cardiopulmonary symptoms. We also correlated findings with previously measured biomarkers. We used logistic regression and linear regression models to adjust for potential confounders including age, sex, body mass index, time since SARS-CoV-2 infection, and hospitalization for acute SARS-CoV-2 infection, with sensitivity analyses adjusting for medical history. RESULTS: Sixty participants (unselected for symptoms, median age 53, 42% female, 87% non- hospitalized) were studied at median 17.6 months following SARS-CoV-2 infection. On maximal CPET, 18/37 (49%) with symptoms had reduced exercise capacity (peak VO 2 <85% predicted) compared to 3/19 (16%) without symptoms (p=0.02). The adjusted peak VO 2 was 5.2 ml/kg/min (95%CI 2.1-8.3; p=0.001) or 16.9% lower actual compared to predicted (95%CI 4.3- 29.6; p=0.02) among those with symptoms compared to those without symptoms. Chronotropic incompetence was present among 12/21 (57%) with reduced VO 2 including 11/37 (30%) with symptoms and 1/19 (5%) without (p=0.04). Inflammatory markers (hsCRP, IL-6, TNF-α) and SARS-CoV-2 antibody levels measured early in PASC were negatively correlated with peak VO 2 more than 1 year later. Late-gadolinium enhancement on CMR and arrhythmias on ambulatory monitoring were not present. CONCLUSIONS: We found evidence of objectively reduced exercise capacity among those with cardiopulmonary symptoms more than 1 year following COVID-19, which was associated with elevated inflammatory markers early in PASC. Chronotropic incompetence may explain exercise intolerance among some with cardiopulmonary phenotype Long COVID. Key Points: Long COVID symptoms were associated with reduced exercise capacity on cardiopulmonary exercise testing more than 1 year after SARS-CoV-2 infection. The most common abnormal finding was chronotropic incompetence. Reduced exercise capacity was associated with early elevations in inflammatory markers.

Chronic viral coinfections differentially affect the likelihood of developing long COVID.

BACKGROUNDThe presence and reactivation of chronic viral infections, such as EBV, CMV, and HIV, have been proposed as potential contributors to long COVID (LC), but studies in well-characterized postacute cohorts of individuals with COVID-19 over a longer time course consistent with current case definitions of LC are limited.METHODSIn a cohort of 280 adults with prior SARS-CoV-2 infection, we assessed the presence and types of LC symptoms and prior medical history (including COVID-19 history and HIV status) and performed serological testing for EBV and CMV using a commercial laboratory. We used covariate-adjusted binary logistic regression models to identify independent associations between variables and LC symptoms.RESULTSWe observed that LC symptoms, such as fatigue and neurocognitive dysfunction, at a median of 4 months following initial diagnosis were independently associated with serological evidence suggesting recent EBV reactivation (early antigen-diffuse IgG positivity) or high nuclear antigen (EBNA) IgG levels but not with ongoing EBV viremia. Serological evidence suggesting recent EBV reactivation (early antigen-diffuse IgG positivity) was most strongly associated with fatigue (OR = 2.12). Underlying HIV infection was also independently associated with neurocognitive LC (OR = 2.5). Interestingly, participants who had serologic evidence of prior CMV infection were less likely to develop neurocognitive LC (OR = 0.52).CONCLUSIONOverall, these findings suggest differential effects of chronic viral coinfections on the likelihood of developing LC and association with distinct syndromic patterns. Further assessment during the acute phase of COVID-19 is warranted.TRIAL REGISTRATIONLong-term Impact of Infection with Novel Coronavirus; ClinicalTrials.gov NCT04362150.FUNDINGThis work was supported by NIH/National Institute of Allergy and Infectious Diseases grants (3R01AI141003-03S1, R01AI158013, and K24AI145806); the Zuckerberg San Francisco General Hospital Department of Medicine and Division of HIV, Infectious Diseases, and Global Medicine; and the UCSF-Bay Area Center for AIDS Research (P30-AI027763).

Higher Levels of Cerebrospinal Fluid and Plasma Neurofilament Light in Human Immunodeficiency Virus-Associated Distal Sensory Polyneuropathy.

BACKGROUND: Neurofilament light (NFL) chain concentrations, reflecting axonal damage, are seen in several polyneuropathies but have not been studied in human immunodeficiency virus (HIV) distal sensory polyneuropathy (DSP). We evaluated NFL in cerebrospinal fluid (CSF) and plasma in relation to DSP in people with HIV (PWH) from 2 independent cohorts and in people without HIV (PWoH). METHODS: Cohort 1 consisted of PWH from the CHARTER Study. Cohort 2 consisted of PWH and PWoH from the HIV Neurobehavioral Research Center (HNRC). We evaluated DSP signs and symptoms in both cohorts. Immunoassays measured NFL in CSF for all and for plasma as well in Cohort 2. RESULTS: Cohort 1 consisted of 111 PWH, mean ± SD age 56.8 ± 8.32 years, 15.3% female, 38.7% Black, 49.6% White, current CD4+ T-cells (median, interquartile range [IQR]) 532/µL (295, 785), 83.5% with plasma HIV RNA ≤50 copies/mL. Cohort 2 consisted of 233 PWH of similar demographics to PWH in Cohort 1 but also 51 PWoH, together age 58.4 ± 6.68 years, 41.2% female, 18.0% Black, Hispanic, non-Hispanic White 52.0%, 6.00% White. In both cohorts of PWH, CSF and plasma NFL were significantly higher in both PWH with DSP signs. Findings were similar, albeit not significant, for PWoH. The observed relationships were not explained by confounds. CONCLUSIONS: Both plasma and CSF NFL were elevated in PWH and PWoH with DSP. The convergence of our findings with others demonstrates that NFL is a reliable biomarker reflecting peripheral nerve injury. Biomarkers such as NFL might provide, validate, and optimize clinical trials of neuroregenerative strategies in HIV DSP.

Evaluation of Severe Acute Respiratory Syndrome Coronavirus 2 Nucleocapsid Antigen in the Blood as a Diagnostic Test for Infection and Infectious Viral Shedding.

Background: SARS-CoV-2 nucleocapsid antigen can be detected in plasma, but little is known about its performance as a diagnostic test for acute SARS-CoV-2 infection or infectious viral shedding among nonhospitalized individuals. Methods: We used data generated from anterior nasal and blood samples collected in a longitudinal household cohort of SARS-CoV-2 cases and contacts. Participants were classified as true positives if polymerase chain reaction (PCR) positive for SARS-CoV-2 and as true negatives if PCR negative and seronegative. Infectious viral shedding was determined by the cytopathic effect from viral culture. Stratified by 7 days after symptom onset, we constructed receiver operating characteristic (ROC) curves to describe optimized accuracy (Youden index), optimized sensitivity, and specificity. Results: Of 80 participants, 58 (73%) were true positives while 22 (27%) were true negatives. Using the manufacturer's cutoff of 1.25 pg/mL for evaluating infection, sensitivity was higher from 0 to 7 days (77.6% [95% confidence interval {CI}, 64%-88.2%]) than from 8 to 14 days (43.2% [95% CI, 31.1%-54.5%]) after symptom onset; specificity was unchanged at 100% (95% CI, 88.1%-100%). This test had higher sensitivity (100% [95% CI, 88.4%-100%]) and lower specificity (65% [95% CI, 40.8%-84.6%]) for infectious viral shedding as compared with infection, particularly within the first week of symptom onset. Although the presence of N-antigen correlated with infectious viral shedding (r = 0.63; P < .01), sensitivity still declined over time. Additional cutoffs from ROC curves were identified to optimize sensitivity and specificity. Conclusions: We found that this SARS-CoV-2 N-antigen test was highly sensitive for detecting early but not late infectious viral shedding, making it a viable screening test for community-dwelling individuals to inform isolation practices.

Impact of Pre-Existing Chronic Viral Infection and Reactivation on the Development of Long COVID.

The presence and reactivation of chronic viral infections such as Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human immunodeficiency virus (HIV) have been proposed as potential contributors to Long COVID (LC), but studies in well-characterized post-acute cohorts of individuals with COVID-19 over a longer time course consistent with current case definitions of LC are limited. In a cohort of 280 adults with prior SARS-CoV-2 infection, we observed that LC symptoms such as fatigue and neurocognitive dysfunction at a median of 4 months following initial diagnosis were independently associated with serological evidence of recent EBV reactivation (early antigen-D [EA-D] IgG positivity) or high nuclear antigen IgG levels, but not with ongoing EBV viremia. Evidence of EBV reactivation (EA-D IgG) was most strongly associated with fatigue (OR 2.12). Underlying HIV infection was also independently associated with neurocognitive LC (OR 2.5). Interestingly, participants who had serologic evidence of prior CMV infection were less likely to develop neurocognitive LC (OR 0.52) and tended to have less severe (>5 symptoms reported) LC (OR 0.44). Overall, these findings suggest differential effects of chronic viral co-infections on the likelihood of developing LC and predicted distinct syndromic patterns. Further assessment during the acute phase of COVID-19 is warranted. SUMMARY: The authors found that Long COVID symptoms in a post-acute cohort were associated with serological evidence of recent EBV reactivation and pre-existing HIV infection when adjusted for participant factors, sample timing, comorbid conditions and prior hospitalization, whereas underlying CMV infection was associated with a decreased risk of Long COVID.

Postacute sequelae and adaptive immune responses in people with HIV recovering from SARS-COV-2 infection.

BACKGROUND: Limited data are available on the long-term clinical and immunologic consequences of SARS-CoV-2 infection in people with HIV (PWH). METHODS: We measured SARS-CoV-2-specific humoral and cellular responses in people with and without HIV recovering from COVID-19 ( n  = 39 and n  = 43, respectively) using binding antibody, surrogate virus neutralization, intracellular cytokine staining, and inflammatory marker assays. We identified individuals experiencing postacute sequelae of SARS-CoV-2 infection (PASC) and evaluated immunologic parameters. We used linear regression and generalized linear models to examine differences by HIV status in the magnitude of inflammatory and virus-specific antibody and T-cell responses, as well as differences in the prevalence of PASC. RESULTS: Among PWH, we found broadly similar SARS-CoV-2-specific antibody and T-cell responses as compared with a well matched group of HIV-negative individuals. PWH had 70% lower relative levels of SARS-CoV-2-specific memory CD8 + T cells ( P  = 0.007) and 53% higher relative levels of PD-1+ SARS-CoV-2-specific CD4 + T cells ( P  = 0.007). Higher CD4 + /CD8 + ratio was associated with lower PD-1 expression on SARS-CoV-2-specific CD8 + T cells (0.34-fold effect, P  = 0.02). HIV status was strongly associated with PASC (odds ratio 4.01, P  = 0.008), and levels of certain inflammatory markers (IL-6, TNF-alpha, and IP-10) were associated with persistent symptoms. CONCLUSION: We identified potentially important differences in SARS-CoV-2-specific CD4 + and CD8 + T cells in PWH and HIV-negative participants that might have implications for long-term immunity conferred by natural infection. HIV status strongly predicted the presence of PASC. Larger and more detailed studies of PASC in PWH are urgently needed.

Higher cerebrospinal fluid biomarkers of neuronal injury in HIV-associated neurocognitive impairment.

We evaluated whether biomarkers of age-related neuronal injury and amyloid metabolism are associated with neurocognitive impairment (NCI) in people with and without HIV (PWH, PWoH). This was a cross-sectional study of virally suppressed PWH and PWoH. NCI was assessed using a validated test battery; global deficit scores (GDS) quantified overall performance. Biomarkers in cerebrospinal fluid (CSF) were quantified by immunoassay: neurofilament light (NFL), total Tau (tTau), phosphorylated Tau 181 (pTau181), amyloid beta (Aß)42, and Aß40. Factor analysis was used to reduce biomarker dimensionality. Participants were 256 virally suppressed PWH and 42 PWoH, 20.2% female, 17.1% Black, 7.1% Hispanic, 60.2% non-Hispanic White, and 15.6% other race/ethnicities, mean (SD) age 56.7 (6.45) years. Among PWH, the best regression model for CSF showed that higher tTau (ß = 0.723, p = 3.79e-5) together with lower pTau181 (ß = -0.510, p = 0.0236) best-predicted poor neurocognitive performance. In univariable analysis, only higher tTau was significantly correlated with poor neurocognitive performance (tTau r = 0.214, p = 0.0006; pTau181 r = 0.00248, p = 0.969). Among PWoH, no CSF biomarkers were significantly associated with worse NCI. Predicted residual error sum of squares (PRESS) analysis showed no evidence of overfitting. Poorer neurocognitive performance in aging PWH was associated with higher CSF tTau, a marker of age-related neuronal injury, but not with biomarkers of amyloid metabolism. The findings suggest that HIV might interact with age-related neurodegeneration to contribute to cognitive decline in PWH.

Markers of fungal translocation are elevated during post-acute sequelae of SARS-CoV-2 and induce NF-κB signaling.

Long COVID, a type of post-acute sequelae of SARS-CoV-2 (PASC), has been associated with sustained elevated levels of immune activation and inflammation. However, the mechanisms that drive this inflammation remain unknown. Inflammation during acute coronavirus disease 2019 could be exacerbated by microbial translocation (from the gut and/or lung) to blood. Whether microbial translocation contributes to inflammation during PASC is unknown. We did not observe a significant elevation in plasma markers of bacterial translocation during PASC. However, we observed higher levels of fungal translocation - measured as ß-glucan, a fungal cell wall polysaccharide - in the plasma of individuals experiencing PASC compared with those without PASC or SARS-CoV-2-negative controls. The higher ß-glucan correlated with higher inflammation and elevated levels of host metabolites involved in activating N-methyl-d-aspartate receptors (such as metabolites within the tryptophan catabolism pathway) with established neurotoxic properties. Mechanistically, ß-glucan can directly induce inflammation by binding to myeloid cells (via Dectin-1) and activating Syk/NF-κB signaling. Using a Dectin-1/NF-κB reporter model, we found that plasma from individuals experiencing PASC induced higher NF-κB signaling compared with plasma from negative controls. This higher NF-κB signaling was abrogated by piceatannol (Syk inhibitor). These data suggest a potential targetable mechanism linking fungal translocation and inflammation during PASC.

Plasma Markers of Neurologic Injury and Inflammation in People With Self-Reported Neurologic Postacute Sequelae of SARS-CoV-2 Infection.

BACKGROUND AND OBJECTIVES: The biologic mechanisms underlying neurologic postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC) are incompletely understood. METHODS: We measured markers of neurologic injury (glial fibrillary acidic protein [GFAP], neurofilament light chain [NfL]) and soluble markers of inflammation among a cohort of people with prior confirmed SARS-CoV-2 infection at early and late recovery after the initial illness (defined as less than and greater than 90 days, respectively). The primary clinical outcome was the presence of self-reported CNS PASC symptoms during the late recovery time point. We compared fold changes in marker values between those with and without CNS PASC symptoms using linear mixed-effects models and examined relationships between neurologic and immunologic markers using rank linear correlations. RESULTS: Of 121 individuals, 52 reported CNS PASC symptoms. During early recovery, those who went on to report CNS PASC symptoms had elevations in GFAP (1.3-fold higher mean ratio, 95% CI 1.04-1.63, p = 0.02), but not NfL (1.06-fold higher mean ratio, 95% CI 0.89-1.26, p = 0.54). During late recovery, neither GFAP nor NfL levels were elevated among those with CNS PASC symptoms. Although absolute levels of NfL did not differ, those who reported CNS PASC symptoms demonstrated a stronger downward trend over time in comparison with those who did not report CNS PASC symptoms (p = 0.041). Those who went on to report CNS PASC also exhibited elevations in interleukin 6 (48% higher during early recovery and 38% higher during late recovery), monocyte chemoattractant protein 1 (19% higher during early recovery), and tumor necrosis factor α (19% higher during early recovery and 13% higher during late recovery). GFAP and NfL correlated with levels of several immune activation markers during early recovery; these correlations were attenuated during late recovery. DISCUSSION: Self-reported neurologic symptoms present approximately 4 months after SARS-CoV-2 infection are associated with elevations in markers of neurologic injury and inflammation at earlier time points. Some inflammatory pathways seem to be involved months after acute infection. Additional work will be needed to better characterize these processes and to identify interventions to prevent or treat this condition.

Role of antibodies, inflammatory markers, and echocardiographic findings in postacute cardiopulmonary symptoms after SARS-CoV-2 infection.

Shortness of breath, chest pain, and palpitations occur as postacute sequelae of COVID-19, but whether symptoms are associated with echocardiographic abnormalities, cardiac biomarkers, or markers of systemic inflammation remains unknown. In a cross-sectional analysis, we assessed symptoms, performed echocardiograms, and measured biomarkers among adults more than 8 weeks after confirmed SARS-CoV-2 infection. We modeled associations between symptoms and baseline characteristics, echocardiographic findings, and biomarkers using logistic regression. We enrolled 102 participants at a median of 7.2 months following COVID-19 onset; 47 individuals reported dyspnea, chest pain, or palpitations. Median age was 52 years, and 41% of participants were women. Female sex, hospitalization, IgG antibody against SARS-CoV-2 receptor binding domain, and C-reactive protein were associated with symptoms. Regarding echocardiographic findings, 4 of 47 participants (9%) with symptoms had pericardial effusions compared with 0 of 55 participants without symptoms; those with effusions had a median of 4 symptoms compared with a median of 1 symptom in those without effusions. There was no strong evidence for a relationship between symptoms and echocardiographic functional parameters or other biomarkers. Among adults more than 8 weeks after SARS-CoV-2 infection, SARS-CoV-2 RBD antibodies, markers of inflammation, and, possibly, pericardial effusions are associated with cardiopulmonary symptoms. Investigation into inflammation as a mechanism underlying postacute sequelae of COVID-19 is warranted.

Markers of Immune Activation and Inflammation in Individuals With Postacute Sequelae of Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

BACKGROUND: The biological processes associated with postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC) are unknown. METHODS: We measured soluble markers of inflammation in a SARS-CoV-2 recovery cohort at early (<90 days) and late (>90 days) timepoints. We defined PASC as the presence of 1 or more coronavirus disease 2019 (COVID-19)-attributed symptoms beyond 90 days. We compared fold-changes in marker values between those with and without PASC using mixed-effects models with terms for PASC and early and late recovery time periods. RESULTS: During early recovery, those who went on to develop PASC generally had higher levels of cytokine biomarkers including tumor necrosis factor-α (1.14-fold higher mean ratio [95% confidence interval {CI}, 1.01-1.28]; P = .028) and interferon-γ-induced protein 10 (1.28-fold higher mean ratio [95% CI, 1.01-1.62]; P = .038). Among those with PASC, there was a trend toward higher interleukin 6 levels during early recovery (1.29-fold higher mean ratio [95% CI, .98-1.70]; P = .07), which became more pronounced in late recovery (1.44-fold higher mean ratio [95% CI, 1.11-1.86]; P < .001). These differences were more pronounced among those with a greater number of PASC symptoms. CONCLUSIONS: Persistent immune activation may be associated with ongoing symptoms following COVID-19. Further characterization of these processes might identify therapeutic targets for those experiencing PASC.

Molecular and Clinical Activity of CDX-3379, an Anti-ErbB3 Monoclonal Antibody, in Head and Neck Squamous Cell Carcinoma Patients.

PURPOSE: ErbB3 and its ligand neuregulin-1 (NRG1) are widely expressed in head and neck squamous cell carcinoma (HNSCC) and associated with tumor progression. A "window-of-opportunity" study (NCT02473731) was conducted to evaluate the pharmacodynamic effects of CDX-3379, an anti-ErbB3 mAb, in patients with HNSCC. PATIENTS AND METHODS: Twelve patients with newly diagnosed, operable HNSCC received two infusions of CDX-3379 (1,000 mg) at a 2-week interval prior to tumor resection. The primary study objective was to achieve ≥50% reduction in tumor ErbB3 signaling (phosphorylation of ErbB3; pErbB3) in ≥30% of patients. Other potential tumor biomarkers, pharmacokinetics, safety, and tumor measurements were also assessed. RESULTS: pErbB3 was detectable in all tumors prior to treatment and decreased for 10 of 12 (83%) patients following CDX-3379 dosing, with ≥50% reduction in 7 of 12 (58%; P = 0.04; 95% confidence interval, 27.7%-84.8%). Target trough CDX-3379 serum levels were achieved in all patients. CDX-3379 treatment-related toxicity was grade 1-2 and included diarrhea, fatigue, and acneiform dermatitis. Five of 12 (42%) patients had shrinkage in tumor burden, including a marked clinical response in a patient with human papillomavirus-negative oral cavity HNSCC. All patients with tumor shrinkage had tumors that expressed both NRG1 and ErbB3 and demonstrated reduced pErbB3 with CDX-3379 treatment. CONCLUSIONS: This study demonstrates that CDX-3379 can inhibit tumor ErbB3 phosphorylation in HNSCC. CDX-3379 was well tolerated and associated with measurable tumor regression. A phase II study (NCT03254927) has been initiated to evaluate CDX-3379 in combination with cetuximab for patients with advanced HNSCC.

p95HER2-T cell bispecific antibody for breast cancer treatment.

T cell bispecific antibodies (TCBs) are engineered molecules that include, within a single entity, binding sites to the T cell receptor and to tumor-associated or tumor-specific antigens. The receptor tyrosine kinase HER2 is a tumor-associated antigen in ~25% of breast cancers. TCBs targeting HER2 may result in severe toxicities, likely due to the expression of HER2 in normal epithelia. About 40% of HER2-positive tumors express p95HER2, a carboxyl-terminal fragment of HER2. Using specific antibodies, here, we show that p95HER2 is not expressed in normal tissues. We describe the development of p95HER2-TCB and show that it has a potent antitumor effect on p95HER2-expressing breast primary cancers and brain lesions. In contrast with a TCB targeting HER2, p95HER2-TCB has no effect on nontransformed cells that do not overexpress HER2. These data pave the way for the safe treatment of a subgroup of HER2-positive tumors by targeting a tumor-specific antigen.

High p95HER2/HER2 Ratio Associated With Poor Outcome in Trastuzumab-Treated HER2-Positive Metastatic Breast Cancer NCCTG N0337 and NCCTG 98-32-52 (Alliance).

Purpose: p95HER2 is a truncated form of HER2 that confers resistance to trastuzumab in vitro, but clinical results have been conflicting to date. Given that p95HER2 levels correlate with total HER2 expression levels, which confer better outcomes, we sought to evaluate the p95HER2/HER2 ratio in the North Central Cancer Treatment Group N0337 and N98-32-52 trials.Experimental Design: The HERmark assay and VeraTag technology (Monogram Biosciences) were used to measure total HER2 and p95HER2 expression levels in 91 patient samples.Results: In the multivariate model, increasing total HER2 level was significantly associated with longer (OS; HR, 0.33; P = 0.002) and decreasing p95HER2 level was significantly associated with longer OS (HR, 4.2; P = 0.01). Total HER2 expression level was significantly associated with longer progression-free survival (PFS) (HR, 0.57; P = 0.04), whereas p95HER2 level was not (HR, 1.7; P = 0.25). However, there was a positive association between p95HER2 and total HER2 expression levels (R2 = 0.48; P < 0.001). Consistent with our hypothesis, the ratio of p95HER2/HER2 was significantly associated with worsening PFS (HR, 1.7; P = 0.04) and OS (HR, 2.8; P = 0.002). Patients with the highest tertile of p95HER2/HER2 values had significantly less favorable PFS (HR, 1.8; P = 0.06) and OS (HR, 2.3; P = 0.02).Conclusions: A high p95HER2/HER2 ratio identified patients with metastatic breast cancer with poor outcomes on trastuzumab-based therapies. Further investigation of the p95HER2/HER2 ratio as a potential prognostic or predictive biomarker for HER2-targeted therapy is warranted. Clin Cancer Res; 24(13); 3053-8. ©2018 AACR.

p95HER2 Methionine 611 Carboxy-Terminal Fragment Is Predictive of Trastuzumab Adjuvant Treatment Benefit in the FinHer Trial.

Purpose: Expression of p95HER2 (p95), a truncated form of the HER2 receptor, which lacks the trastuzumab binding site but retains kinase activity, has been reported as a prognostic biomarker for poor outcomes in patients with trastuzumab-treated HER2-positive metastatic breast cancer. The impact of p95 expression on trastuzumab treatment efficacy in early HER2-positive breast cancer is less clear. In the current study, p95 was tested as a predictive marker of trastuzumab treatment benefit in the HER2-positive subset of the FinHer adjuvant phase III trial.Experimental Design: In the FinHer trial, 232 patients with HER2-positive early breast cancer were randomized to receive chemotherapy plus 9 weeks of trastuzumab or no trastuzumab treatment. Quantitative p95 protein expression was measured in formalin-fixed paraffin-embedded samples using the p95 VeraTag assay (Monogram Biosciences), specific for the M611 form of p95. Quantitative HER2 protein expression was measured using the HERmark assay (Monogram Biosciences). Distant disease-free survival (DDFS) was used as the primary outcome measure.Results: In the arm receiving chemotherapy only, increasing log10(p95) correlated with shorter DDFS (HR, 2.0; P = 0.02). In the arm receiving chemotherapy plus trastuzumab (N = 95), increasing log10(p95) was not correlated with a shorter DDFS. In a combined analysis of both treatment arms, high breast tumor p95 content was significantly correlated with trastuzumab treatment benefit in multivariate models (interaction P = 0.01).Conclusions: A high p95HER2/HER2 ratio identified patients with metastatic breast cancer with poor outcomes on trastuzumab-based therapies. Further investigation of the p95HER2/HER2 ratio as a potential prognostic or predictive biomarker for HER2-targeted therapy is warranted. Clin Cancer Res; 24(13); 3046-52. ©2018 AACR.

Adverse Health Effects of Thirdhand Smoke: From Cell to Animal Models.

The newly identified smoke hazard, thirdhand smoke (THS), has gained public attention in recent years but its health impact and biological effects are largely unknown. THS may be defined by "the four Rs": tobacco chemicals that remain, react, re-emit, and/or are resuspended long after active smoking has ceased. This review summarizes recent research progress in the effects of THS on genotoxicity, metabolism and early life development using cellular and animal models. We first reported that THS generated in laboratory systems caused significant DNA damage in human cell lines. Our finding that THS significantly induces oxidative base lesions has been confirmed in skin wounds of mice models exposed to THS. THS also induced metabolomic changes in human reproductive cell lines. Furthermore, we demonstrated that early exposure to THS not only negatively impacts body weight in both male and female mice, but also induces persistent changes to immunological parameters in peripheral blood in these mice. These results indicate that THS is genotoxic at realistic experimental doses and that there may be a window of susceptibility for some forms of cellular damage induced by THS.

Prolonged Response to Trastuzumab in a Patient With HER2-Nonamplified Breast Cancer With Elevated HER2 Dimerization Harboring an ERBB2 S310F Mutation.

In the current genomic era, increasing evidence demonstrates that approximately 2% of HER2-negative breast cancers, by current standard testings, harbor activating mutations of ERBB2. However, whether patients with HER2-negative breast cancer with activating mutations of ERBB2 also experience response to anti-HER2 therapies remains unclear. This case report describes a patient with HER2-nonamplified heavily pretreated breast cancer who experienced prolonged response to trastuzumab in combination with pertuzumab and fulvestrant. Further molecular analysis demonstrated that her tumors had an elevated HER2 dimerization that corresponded to ERBB2 S310F mutation. Located in the extracellular domain of the HER2 protein, this mutation was reported to promote noncovalent dimerization that results in the activation of the downstream signaling pathways. This case highlights the fact that HER2-targeted therapy may be valuable in patients harboring an ERBB2 S310F mutation.