Enhancing Efficacy of TCR-engineered CD4 + T Cells Via Coexpression of CD8α.

Adoptive cell therapy with T cells expressing affinity-enhanced T-cell receptors (TCRs) is a promising treatment for solid tumors. Efforts are ongoing to further engineer these T cells to increase the depth and durability of clinical responses and broaden efficacy toward additional indications. In the present study, we investigated one such approach: T cells were transduced with a lentiviral vector to coexpress an affinity-enhanced HLA class I-restricted TCR directed against MAGE-A4 alongside a CD8α coreceptor. We hypothesized that this approach would enhance CD4 + T-cell helper and effector functions, possibly leading to a more potent antitumor response. Activation of transduced CD4 + T cells was measured by detecting CD40 ligand expression on the surface and cytokine and chemokine secretion from CD4 + T cells and dendritic cells cultured with melanoma-associated antigen A4 + tumor cells. In addition, T-cell cytotoxic activity against 3-dimensional tumor spheroids was measured. Our data demonstrated that CD4 + T cells coexpressing the TCR and CD8α coreceptor displayed enhanced responses, including CD40 ligand expression, interferon-gamma secretion, and cytotoxic activity, along with improved dendritic cell activation. Therefore, our study supports the addition of the CD8α coreceptor to HLA class I-restricted TCR-engineered T cells to enhance CD4 + T-cell functions, which may potentially improve the depth and durability of antitumor responses in patients.

Efficacy and Safety of Therapeutic-Dose Heparin vs Standard Prophylactic or Intermediate-Dose Heparins for Thromboprophylaxis in High-risk Hospitalized Patients With COVID-19: The HEP-COVID Randomized Clinical Trial.

Importance: Hospitalized patients with COVID-19 are at risk for venous and arterial thromboembolism and death. Optimal thromboprophylaxis dosing in high-risk patients is unknown. Objective: To evaluate the effects of therapeutic-dose low-molecular-weight heparin (LMWH) vs institutional standard prophylactic or intermediate-dose heparins for thromboprophylaxis in high-risk hospitalized patients with COVID-19. Design, Setting, and Participants: The HEP-COVID multicenter randomized clinical trial recruited hospitalized adult patients with COVID-19 with D-dimer levels more than 4 times the upper limit of normal or sepsis-induced coagulopathy score of 4 or greater from May 8, 2020, through May 14, 2021, at 12 academic centers in the US. Interventions: Patients were randomized to institutional standard prophylactic or intermediate-dose LMWH or unfractionated heparin vs therapeutic-dose enoxaparin, 1 mg/kg subcutaneous, twice daily if creatinine clearance was 30 mL/min/1.73 m2 or greater (0.5 mg/kg twice daily if creatinine clearance was 15-29 mL/min/1.73 m2) throughout hospitalization. Patients were stratified at the time of randomization based on intensive care unit (ICU) or non-ICU status. Main Outcomes and Measures: The primary efficacy outcome was venous thromboembolism (VTE), arterial thromboembolism (ATE), or death from any cause, and the principal safety outcome was major bleeding at 30 ± 2 days. Data were collected and adjudicated locally by blinded investigators via imaging, laboratory, and health record data. Results: Of 257 patients randomized, 253 were included in the analysis (mean [SD] age, 66.7 [14.0] years; men, 136 [53.8%]; women, 117 [46.2%]); 249 patients (98.4%) met inclusion criteria based on D-dimer elevation and 83 patients (32.8%) were stratified as ICU-level care. There were 124 patients (49%) in the standard-dose vs 129 patients (51%) in the therapeutic-dose group. The primary efficacy outcome was met in 52 of 124 patients (41.9%) (28.2% VTE, 3.2% ATE, 25.0% death) with standard-dose heparins vs 37 of 129 patients (28.7%) (11.7% VTE, 3.2% ATE, 19.4% death) with therapeutic-dose LMWH (relative risk [RR], 0.68; 95% CI, 0.49-0.96; P = .03), including a reduction in thromboembolism (29.0% vs 10.9%; RR, 0.37; 95% CI, 0.21-0.66; P < .001). The incidence of major bleeding was 1.6% with standard-dose vs 4.7% with therapeutic-dose heparins (RR, 2.88; 95% CI, 0.59-14.02; P = .17). The primary efficacy outcome was reduced in non-ICU patients (36.1% vs 16.7%; RR, 0.46; 95% CI, 0.27-0.81; P = .004) but not ICU patients (55.3% vs 51.1%; RR, 0.92; 95% CI, 0.62-1.39; P = .71). Conclusions and Relevance: In this randomized clinical trial, therapeutic-dose LMWH reduced major thromboembolism and death compared with institutional standard heparin thromboprophylaxis among inpatients with COVID-19 with very elevated D-dimer levels. The treatment effect was not seen in ICU patients. Trial Registration: ClinicalTrials.gov Identifier: NCT04401293.

Treatment-Dose LMWH versus Prophylactic/Intermediate Dose Heparins in High-Risk COVID-19 Inpatients: Rationale and Design of the HEP-COVID Trial.

Coronavirus disease-2019 (COVID-19) has been associated with significant risk of venous thromboembolism (VTE), arterial thromboembolism (ATE), and mortality particularly among hospitalized patients with critical illness and elevated D-dimer (Dd) levels. Conflicting data have yet to elucidate optimal thromboprophylaxis dosing. HEP-COVID (NCT04401293) is a phase 3, multicenter, pragmatic, prospective, randomized, pseudo-blinded, active control trial to evaluate efficacy and safety of therapeutic-dose low-molecular-weight heparin (LMWH) versus prophylactic-/intermediate-dose LMWH or unfractionated heparin (UFH) for prevention of a primary efficacy composite outcome of VTE, ATE, and all-cause mortality 30 ± 2 days post-enrollment. Eligible patients have COVID-19 diagnosis by nasal swab or serologic testing, requirement for supplemental oxygen per investigator judgment, and Dd >4 × upper limit of normal (ULN) or sepsis-induced coagulopathy score ≥4. Subjects are randomized to enoxaparin 1 mg/kg subcutaneous (SQ)/two times a day (BID) (creatinine clearance [CrCl] ≥ 30 mL/min) or 0.5 mg/kg (CrCl 15-30 mL/min) versus local institutional prophylactic regimens including (1) UFH up to 22,500 IU (international unit) daily (divided BID or three times a day), (2) enoxaparin 30 and 40 mg SQ QD (once daily) or BID, or (3) dalteparin 2,500 IU or 5,000 IU QD. The principal safety outcome is major bleeding. Events are adjudicated locally. Based on expected 40% relative risk reduction with treatment-dose compared with prophylactic-dose prophylaxis, 308 subjects will be enrolled (assuming 20% drop-out) to achieve 80% power. Distinguishing design features include an enriched population for the composite endpoint anchored on Dd >4 × ULN, stratification by intensive care unit (ICU) versus non-ICU, and the ability to capture asymptomatic proximal deep venous thrombosis via screening ultrasonography prior to discharge.

Preclinical evaluation of an affinity-enhanced MAGE-A4-specific T-cell receptor for adoptive T-cell therapy.

A substantial obstacle to the success of adoptive T cell-based cancer immunotherapy is the sub-optimal affinity of T-cell receptors (TCRs) for most tumor antigens. Genetically engineered TCRs that have enhanced affinity for specific tumor peptide-MHC complexes may overcome this barrier. However, this enhancement risks increasing weak TCR cross-reactivity to other antigens expressed by normal tissues, potentially leading to clinical toxicities. To reduce the risk of such adverse clinical outcomes, we have developed an extensive preclinical testing strategy, involving potency testing using 2D and 3D human cell cultures and primary tumor material, and safety testing using human primary cell and cell-line cross-reactivity screening and molecular analysis to predict peptides recognized by the affinity-enhanced TCR. Here, we describe this strategy using a developmental T-cell therapy, ADP-A2M4, which recognizes the HLA-A2-restricted MAGE-A4 peptide GVYDGREHTV. ADP-A2M4 demonstrated potent anti-tumor activity in the absence of major off-target cross-reactivity against a range of human primary cells and cell lines. Identification and characterization of peptides recognized by the affinity-enhanced TCR also revealed no cross-reactivity. These studies demonstrated that this TCR is highly potent and without major safety concerns, and as a result, this TCR is now being investigated in two clinical trials (NCT03132922, NCT04044768).

Recovery from Copperhead Snake Envenomation: Role of Age, Sex, Bite Location, Severity, and Treatment.

INTRODUCTION: Few data exist to understand the recovery phase of pit viper envenomation. A recently published placebo-controlled clinical trial affords this opportunity. The purpose of this study is to examine the time course of recovery from copperhead snake (Agkistrodon contortrix) envenomation patients managed with and without the use of antivenom, stratified by age, sex, anatomic site of envenomation, initial severity of envenomation, and geographic region. METHODS: This is a post-hoc subgroup analysis of data from a multi-center double-blinded clinical trial of Fab antivenom (FabAV) vs. placebo. Outcomes were the Patient-Specific Functional Scale (PSFS) score at 3, 7, 10, and 14 days after envenomation. Least-squares mean PSFS score curves were calculated for each subgroup, and repeated measures ANOVA was used to estimate between-group comparisons. RESULTS: Seventy-two subjects were included, of whom 44 received FabAV. Males demonstrated better overall recovery than females (model predicted PSFS score 6.18 vs 4.99; difference 1.19; 95% CI 0.12 to 2.25; p = 0.029). No sex difference was found in response to FabAV. Overall recovery and effect of FabAV were similar in adult vs adolescent patients, patients with upper vs lower extremity envenomation, and patients with initially mild vs moderate envenomation signs. Analysis by geographic location was not successful due to ANOVA mode instability. CONCLUSIONS: Male victims of copperhead snake envenomation demonstrate slightly better recovery than females, but response to Fab antivenom overall is similar across all subgroups studied.

Validity and reliability of telephone administration of the patient-specific functional scale for the assessment of recovery from snakebite envenomation.

OBJECTIVES: Although more than 1.8 million people survive snakebite envenomation each year, their recovery is understudied. Obtaining long-term follow-up is challenging in both high- and low-resource settings. The Patient-Specific Functional Scale (PSFS) is an easily administered, well-accepted patient-reported outcome that is validated for assessing limb recovery from snakebite envenomation. We studied whether the PSFS is valid and reliable when administered by telephone. METHODS: This is a secondary analysis of data from a randomized clinical trial. We analyzed the results of PSFS collected in-person on days 3, 7, 14, 21, and 28 and by telephone on days 10, 17, and 24. We assessed the following scale psychometric properties: (a) content validity (ceiling and floor effects), (b) internal structure and consistency (Cronbach's alpha), and (c) temporal and external validity using Intraclass Correlation Coefficient (ICC). Temporal stability was assessed using Spearman's correlation coefficient and agreement between adjacent in-person and telephonic assessments with Cohen's kappa. Bland Altman analysis was used to assess differential bias in low and high score results. RESULTS: Data from 74 patients were available for analysis. Floor effects were seen in the early post-injury time points (median: 3 (IQR: 0, 5) at 3 days post-enrollment) and ceiling effects in the late time points (median: 9 (IQR: 8, 10). Internal consistency was good to excellent with both in-person (Cronbach α: 0.91 (95%CI 0.88, 0.95)) and telephone administration (0.81 (0.73, 0.89). Temporal stability was also good (ICC: 0.83 (0.72, 0.89) in-person, 0.80 (0.68, 0.88) telephone). A strong linear correlation was found between in-person and telephone administration (Spearman's ρ: 0.83 (CI: 0.78, 0.84), consistency was assessed as excellent (Cohen's κ 0.81 (CI: 0.78, 0.84), and Bland Altman analysis showed no systematic bias. CONCLUSIONS: Telephone administration of the PSFS provides valid, reliable, and consistent data for the assessment of recovery from snakebite envenomation.

Antivenom Treatment Is Associated with Fewer Patients using Opioids after Copperhead Envenomation.

INTRODUCTION: Copperhead envenomation causes local tissue destruction, leading people to seek treatment for the pain and swelling. First-line treatment for the pain is opioid medications. There is rising concern that an initial opioid prescription from the emergency department (ED) can lead to long-term addiction. This analysis sought to determine whether use of Fab antivenom (FabAV) for copperhead envenomation affected opioid use. METHODS: We performed a secondary analysis using data from a randomized clinical trial designed to determine the effect of FabAV on limb injury recovery following mild to moderate copperhead envenomation. Opioid use was a defined secondary outcome in the parent trial. Patients were contacted after discharge, and data were obtained regarding medications used for pain and the patients' functional status. This analysis describes the proportion of patients in each treatment group reporting opioid use at each time point. It also assesses the interaction between functional status and use of opioids. RESULTS: We enrolled 74 patients in the parent trial (45 received FabAV, 29 placebo), of whom 72 were included in this secondary analysis. Thirty-five reported use of any opioids after hospital discharge. A smaller proportion of patients treated with FabAV reported opioid use: 40.9% vs 60.7% of those in the placebo group. The proportion of patients using opioids remained smaller in the FabAV group at each follow-up time point. Controlling for confounders and interactions between variables, the model estimated that the odds ratio of using opioids after hospital discharge among those who received placebo was 5.67 times that of those who received FabAV. Patients who reported higher baseline pain, those with moderate as opposed to mild envenomation, and females were more likely to report opioid use at follow-up. Patients with ongoing limitations to functional status had an increased probability of opioid use, with a stronger association over time. Opioid use corresponded with the trial's predefined criteria for full recovery, with only two patients reporting opioid use in the 24 hours prior to achieving full limb recovery and no patients in either group reporting opioid use after full limb recovery. CONCLUSION: In this study population, the proportion of patients using opioids for pain related to envenomation was smaller in the FabAV treatment group at all follow-up time points.

The Efficacy of Antivenin Latrodectus (Black Widow) Equine Immune F(ab')2 Versus Placebo in the Treatment of Latrodectism: A Randomized, Double-Blind, Placebo-Controlled, Clinical Trial.

STUDY OBJECTIVE: The antivenom currently available for treatment of systemic black widow envenomation (latrodectism) is composed of equine whole immunoglobin. Although considered effective, it has been associated with anaphylaxis and 2 reported fatalities. We test the efficacy and safety of new equine antivenom composed of purified F(ab')2 antibody fragments. METHODS: A randomized, double-blind, placebo-controlled trial was conducted at 16 sites across the United States. Subjects aged 10 years or older with moderate to severe pain because of black widow spider envenomation received F(ab')2 antivenom or placebo. The primary outcome measure was treatment failure, which was defined as failure to achieve and maintain clinically significant reduction in pain for 48 hours posttreatment. Secondary measures of pain intensity differences and summed pain intensity difference were computed. Adverse events were recorded. RESULTS: Sixty patients were treated (29 antivenom and 31 placebo). The mean age was 39 years and 68% were male. There were 15 treatment failures in the antivenom group and 24 in the placebo group (P=.019). Differences in pain intensity difference between groups were lower at each postbaseline point, and the mean summed pain intensity difference was greater for the antivenom group (difference 2,133; 95% confidence interval 177 to 4,090). No deaths or serious drug-related adverse events were detected. CONCLUSION: The F(ab')2 antivenom met the predefined primary outcome of reduced treatment failures. Secondary outcomes of pain intensity difference and summed pain intensity difference also supported efficacy. The rate of symptom improvement in the placebo group was higher than expected, which may be related to enrollment criteria or placebo effect.

The validity, reliability and minimal clinically important difference of the patient specific functional scale in snake envenomation.

OBJECTIVE: Valid, reliable, and clinically relevant outcome measures are necessary in clinical studies of snake envenomation. The aim of this study was to evaluate the psychometric (validity and reliability) and clinimetric (minimal clinically important difference [MCID]) properties of the Patient-Specific Functional Scale (PSFS) in snakebite envenomation. METHODS: We performed a secondary analysis of two existing snakebite trials that measured clinical outcomes using the PSFS as well as other quality of life and functional assessments. Data were collected at 3, 7, 10, and 17 days. Reliability was determined using Cronbach's alpha for internal consistency and the intraclass correlation coefficient (ICC) for temporal stability at 10 and 17 days. Validity was assessed using concurrent validity correlating with the other assessments. The MCID was evaluated using the following criteria: (1) the distribution of stable patients according to both standard error of measurement (SEM) and responsiveness techniques, and (2) anchor-based methods to compare between individuals and to detect discriminant ability of a positive change with a receiver operator characteristic (ROC) curve and optimal cutoff point. RESULTS: A total of 86 patients were evaluated in this study. The average PSFS scores were 5.37 (SD 3.23), 7.95 (SD 2.22), and 9.12 (SD 1.37) at 3, 7, and 10 days, respectively. Negligible floor effect was observed (maximum of 8% at 3 days); however, a ceiling effect was observed at 17 days (25%). The PSFS showed good reliability with an internal consistency of 0.91 (Cronbach's alpha) (95% CI 0.88, 0.95) and a temporal stability of 0.83 (ICC) (95% CI 0.72, 0.89). The PSFS showed a strong positive correlation with quality of life and functional assessments. The MCID was approximately 1.0 for all methods. CONCLUSIONS: With an MCID of approximately 1 point, the PSFS is a valid and reliable tool to assess quality of life and functionality in patients with snake envenomation.

Early administration of Fab antivenom resulted in faster limb recovery in copperhead snake envenomation patients.

BACKGROUND: No previous research has studied whether early snake antivenom administration leads to better clinical outcomes than late antivenom administration in North American pit viper envenomation. METHODS: A secondary analysis of data from a clinical trial of Fab antivenom (FabAV) versus placebo for copperhead snake envenomation was conducted. Patients treated before the median time to FabAV administration were classified as receiving early treatment and those treated after the median time were defined as the late treatment group. A Cox proportional hazards model was used to compare time to full recovery on the Patient-Specific Functional Scale (PSFS) instrument between groups. Secondary analyses compared estimated mean PSFS scores using a generalized linear model and the estimated proportion of patients with full recovery at each time point using logistic regression. To evaluate for confounding, the main analysis was repeated using data from placebo-treated subjects. RESULTS: Forty-five subjects were treated with FabAV at a median of 5.47 h after envenomation. Patients in the early treatment group had a significantly shorter time to full recovery than those treated late (median time: 17 versus 28 days, p = .025). Model-estimated PSFS scores were numerically higher at each time point in the early group. No difference was found between patients treated early versus late with placebo. CONCLUSIONS: In this secondary analysis of trial data, recovery of limb function was faster when Fab antivenom was administered soon after envenomation, as opposed to late administration.

Tuning T-Cell Receptor Affinity to Optimize Clinical Risk-Benefit When Targeting Alpha-Fetoprotein-Positive Liver Cancer.

Patients with hepatocellular carcinoma (HCC) have a poor prognosis and limited therapeutic options. Alpha-fetoprotein (AFP) is often expressed at high levels in HCC and is an established clinical biomarker of the disease. Expression of AFP in nonmalignant liver can occur, particularly in a subset of progenitor cells and during chronic inflammation, at levels typically lower than in HCC. This cancer-specific overexpression indicates that AFP may be a promising target for immunotherapy. We verified expression of AFP in normal and diseased tissue and generated an affinity-optimized T-cell receptor (TCR) with specificity to AFP/HLA-A*02+ tumors. Expression of AFP was investigated using database searches, by qPCR, and by immunohistochemistry (IHC) analysis of a panel of human tissue samples, including normal, diseased, and malignant liver. Using in vitro mutagenesis and screening, we generated a TCR that recognizes the HLA-A*02-restricted AFP158-166 peptide, FMNKFIYEI, with an optimum balance of potency and specificity. These properties were confirmed by an extension of the alanine scan (X-scan) and testing TCR-transduced T cells against normal and tumor cells covering a variety of tissues, cell types, and human leukocyte antigen (HLA) alleles. Conclusion: We have used a combination of physicochemical, in silico, and cell biology methods for optimizing a TCR for improved affinity and function, with properties that are expected to allow TCR-transduced T cells to differentiate between antigen levels on nonmalignant and cancer cells. T cells transduced with this TCR constitute the basis for a trial of HCC adoptive T-cell immunotherapy.

Validity and reliability of telephone administration of the patient-specific functional scale for the assessment of recovery from snakebite envenomation

Objectives Although more than 1.8 million people survive snakebite envenomation each year, their recovery is understudied. Obtaining long-term follow-up is challenging in both high- and low-resource settings. The Patient-Specific Functional Scale (PSFS) is an easily administered, well-accepted patient-reported outcome that is validated for assessing limb recovery from snakebite envenomation. We studied whether the PSFS is valid and reliable when administered by telephone. Methods This is a secondary analysis of data from a randomized clinical trial. We analyzed the results of PSFS collected in-person on days 3, 7, 14, 21, and 28 and by telephone on days 10, 17, and 24. We assessed the following scale psychometric properties: (a) content validity (ceiling and floor effects), (b) internal structure and consistency (Cronbach’s alpha), and (c) temporal and external validity using Intraclass Correlation Coefficient (ICC). Temporal stability was assessed using Spearman’s correlation coefficient and agreement between adjacent in-person and telephonic assessments with Cohen’s kappa. Bland Altman analysis was used to assess differential bias in low and high score results. Results Data from 74 patients were available for analysis. Floor effects were seen in the early post-injury time points (median: 3 (IQR: 0, 5) at 3 days post-enrollment) and ceiling effects in the late time points (median: 9 (IQR: 8, 10). Internal consistency was good to excellent with both in-person (Cronbach a: 0.91 (95%CI 0.88, 0.95)) and telephone administration (0.81 (0.73, 0.89). Temporal stability was also good (ICC: 0.83 (0.72, 0.89) in-person, 0.80 (0.68, 0.88) telephone). A strong linear correlation was found between in-person and telephone administration (Spearman’s Ró: 0.83 (CI: 0.78, 0.84), consistency was assessed as excellent (Cohen’s capa 0.81 (CI: 0.78, 0.84), and Bland Altman analysis showed no systematic bias. Conclusions Telephone administration of the PSFS provides valid, reliable, and consistent data for the assessment of recovery from snakebite envenomation.

Validity and reliability of telephone administration of the patient-specific functional scale for the assessment of recovery from snakebite envenomation

Objectives Although more than 1.8 million people survive snakebite envenomation each year, their recovery is understudied. Obtaining long-term follow-up is challenging in both high- and low-resource settings. The Patient-Specific Functional Scale (PSFS) is an easily administered, well-accepted patient-reported outcome that is validated for assessing limb recovery from snakebite envenomation. We studied whether the PSFS is valid and reliable when administered by telephone. Methods This is a secondary analysis of data from a randomized clinical trial. We analyzed the results of PSFS collected in-person on days 3, 7, 14, 21, and 28 and by telephone on days 10, 17, and 24. We assessed the following scale psychometric properties: (a) content validity (ceiling and floor effects), (b) internal structure and consistency (Cronbach’s alpha), and (c) temporal and external validity using Intraclass Correlation Coefficient (ICC). Temporal stability was assessed using Spearman’s correlation coefficient and agreement between adjacent in-person and telephonic assessments with Cohen’s kappa. Bland Altman analysis was used to assess differential bias in low and high score results. Results Data from 74 patients were available for analysis. Floor effects were seen in the early post-injury time points (median: 3 (IQR: 0, 5) at 3 days post-enrollment) and ceiling effects in the late time points (median: 9 (IQR: 8, 10). Internal consistency was good to excellent with both in-person (Cronbach a: 0.91 (95%CI 0.88, 0.95)) and telephone administration (0.81 (0.73, 0.89). Temporal stability was also good (ICC: 0.83 (0.72, 0.89) in-person, 0.80 (0.68, 0.88) telephone). A strong linear correlation was found between in-person and telephone administration (Spearman’s Ró: 0.83 (CI: 0.78, 0.84), consistency was assessed as excellent (Cohen’s capa 0.81 (CI: 0.78, 0.84), and Bland Altman analysis showed no systematic bias. Conclusions Telephone administration of the PSFS provides valid, reliable, and consistent data for the assessment of recovery from snakebite envenomation.

Adverse Events in the Efficacy of Crotalidae Polyvalent Immune Fab Antivenom vs Placebo in Recovery from Copperhead Snakebite Trial.

OBJECTIVE: To compare the incidence of hypersensitivity reactions following copperhead envenomation treated with Fab antivenom (FabAV) or placebo. METHODS: Patients with copperhead snakebites received treatment and follow-up in a prospective, randomized, double-blind, placebo-controlled trial of FabAV or placebo. The treatment allocation ratio was 2:1 (FabAV:placebo). All of the included patients received at least one dose of study treatment. We reviewed all treatment-emergent adverse events (AEs) using a previously published scale to classify likely hypersensitivity reactions as mild, moderate, or severe. RESULTS: We enrolled 74 patients at 13 sites. Forty-five patients received FabAV, and 29 patients received placebo. Five FabAV patients and 4 placebo patients had moderate envenomations; the rest were mild. Twenty-five FabAV patients and 8 placebo patients had at least 1 AE. Mild skin reactions occurred in 11 (24%) FabAV patients (pruritis, urticaria, rash, ecchymosis, erythema) and 1 (3%) placebo patient (pruritis). Moderate gastrointestinal AEs occurred in 7 (16%) FabAV patients (nausea, vomiting, constipation, diarrhea, oral paresthesia) and in 2 (7%) placebo patients (nausea). Respiratory AEs occurred in 3 (7%) FabAV patients (dyspnea, pulmonary embolism, nasal congestion, sneezing) and no placebo patients. Hypotension occurred in 1 patient in each group. CONCLUSIONS: In a randomized controlled trial of FabAV for copperhead bites, the incidence of hypersensitivity reactions was low. Most reactions were mild skin reactions.

Expert Consensus Guidelines for Stocking of Antidotes in Hospitals That Provide Emergency Care.

We provide recommendations for stocking of antidotes used in emergency departments (EDs). An expert panel representing diverse perspectives (clinical pharmacology, medical toxicology, critical care medicine, hematology/oncology, hospital pharmacy, emergency medicine, emergency medical services, pediatric emergency medicine, pediatric critical care medicine, poison centers, hospital administration, and public health) was formed to create recommendations for antidote stocking. Using a standardized summary of the medical literature, the primary reviewer for each antidote proposed guidelines for antidote stocking to the full panel. The panel used a formal iterative process to reach their recommendation for both the quantity of antidote that should be stocked and the acceptable timeframe for its delivery. The panel recommended consideration of 45 antidotes; 44 were recommended for stocking, of which 23 should be immediately available. In most hospitals, this timeframe requires that the antidote be stocked in a location that allows immediate availability. Another 14 antidotes were recommended for availability within 1 hour of the decision to administer, allowing the antidote to be stocked in the hospital pharmacy if the hospital has a mechanism for prompt delivery of antidotes. The panel recommended that each hospital perform a formal antidote hazard vulnerability assessment to determine its specific need for antidote stocking. Antidote administration is an important part of emergency care. These expert recommendations provide a tool for hospitals that offer emergency care to provide appropriate care of poisoned patients.

Serum paracetamol-protein adducts in ambulatory subjects: Relationship to recent reported paracetamol use.

CONTEXT: Serum paracetamol-protein adducts (PPAs) are a novel potential biomarker of paracetamol exposure. The relationship between serum PPA concentrations and reported paracetamol use in ambulatory adults has not been previously described. MATERIALS AND METHODS: This was a cross-sectional study of ambulatory adults. A detailed medication history was obtained from all subjects and subjects were stratified by reported paracetamol use in the 2 weeks prior to enrolment. Serum PPAs were measured in all subjects and correlated with reported dose, time of last ingestion and demographics. RESULTS: We enrolled 230 in the paracetamol exposure arm and 74 in the no exposure arm. 98/230 (42.6%)of subjects who reported paracetamol exposure had PPA detected and 68/74 (91.9%) of subjects who denied paracetamol exposure had no PPA detected. PPA concentrations were positively correlated with total paracetamol dose and with more recent ingestion. DISCUSSION: Detection of serum PPA generally reflects paracetamol exposure histories in ambulatory adults. Concentrations are well correlated with reported dose and time from last dose. CONCLUSIONS: Serum PPA can be detected with reported therapeutic use of paracetamol but may not be detected in all patients who report taking paracetamol.

The Efficacy of Crotalidae Polyvalent Immune Fab (Ovine) Antivenom Versus Placebo Plus Optional Rescue Therapy on Recovery From Copperhead Snake Envenomation: A Randomized, Double-Blind, Placebo-Controlled, Clinical Trial.

STUDY OBJECTIVE: Copperhead snake (Agkistrodon contortrix) envenomation causes limb injury resulting in pain and disability. It is not known whether antivenom administration improves limb function. We determine whether administration of antivenom improves recovery from limb injury in patients envenomated by copperhead snakes. METHODS: From August 2013 through November 2015, we performed a multicenter, randomized, double-blind, placebo-controlled, clinical trial to evaluate the effect of ovine Crotalidae polyvalent immune Fab (ovine) (CroFab; FabAV) antivenom therapy on recovery of limb function in patients with copperhead snake envenomation at 14 days postenvenomation. The study setting was 18 emergency departments in regions of the United States where copperhead snakes are endemic. Consecutive patients aged 12 years or older with mild- to moderate-severity envenomation received either FabAV or placebo. The primary outcome was limb function 14 days after envenomation, measured by the Patient-Specific Functional Scale. Additional outcomes included the Patient-Specific Functional Scale at other points; the Disorders of the Arm, Shoulder, and Hand, Lower Extremity Functional Scale, and Patient's Global Impression of Change instruments; grip strength; walking speed; quality of life (Patient-Reported Outcomes Measurement Information System Physical Fucntion-10); pain; and analgesic use. RESULTS: Seventy-four patients received study drug (45 FabAV, 29 placebo). Mean age was 43 years (range 12 to 86 years). Fifty-three percent were men, 62% had lower extremity envenomation, and 88% had mild initial severity. The primary outcome, the least square mean Patient-Specific Functional Scale score at 14 days postenvenomation, was 8.6 for FabAV-treated subjects and 7.4 for placebo recipients (difference 1.2; 95% confidence interval 0.1 to 2.3; P=.04). Additional outcome assessments generally favored FabAV. More FabAV-treated subjects experienced treatment-emergent adverse events (56% versus 28%), but few were serious (1 in each group). CONCLUSION: Treatment with FabAV reduces limb disability measured by the Patient-Specific Functional Scale 14 days after copperhead envenomation.

Accuracy of the Structured Medication History Assessment Tool (MedHAT) Compared with Recorded Real-Time Medication Use.

STUDY OBJECTIVE: Medication histories are collected to measure drug exposure in epidemiologic studies, to identify adverse drug events and in clinical practice. The objective of this study was to compare the accuracy of a structured medication history obtained by using the Medication History Assessment Tool (MedHAT) with a medication diary in which subjects recorded real-time medication use. DESIGN: Prospective observational study. SETTING: Outpatient research center. SUBJECTS: Sixty-seven adult healthy volunteers. INTERVENTIONS: Subjects were provided diaries to record the product name, dose quantity, and time that they used a prescription or nonprescription medication, supplement, or vitamin. After a minimum of 30 continuous days of diary use, a final interview was conducted, and medication history data were collected by using the MedHAT. MEASUREMENTS AND MAIN RESULTS: We compared the medications reported during the interview with the medications recorded in the diary for each day to determine the accuracy of the verbal history. The primary outcome was the proportion of matches for each day for each subject. Overall accuracy for medication use for the day preceding the interview was 90%, and accuracy during the 30 days preceding the interview was 76%. Recall was higher for subjects taking prescription medications, those who had more recent medication use, older subjects, and subjects taking a higher proportion of prescription medications. CONCLUSION: The MedHAT system provided relatively high accuracy for immediate past use and for prescription medications and may offer better accuracy than other methods. Medication histories are often inaccurate, however, and may represent an important source of misclassification in epidemiologic studies. Thus medication histories alone should be used cautiously when measuring associations between drug exposure and health outcomes.