What are the 'ideal' features of an adrenaline (epinephrine) auto-injector in the treatment of anaphylaxis?

Evaluations of medical device usability during clinical investigations: a scoping review of clinical study protocols

OBJECTIVE

Combining clinical investigations with usability studies provides valuable information for medical devices evaluation. But both types of study are very different in terms of objectives and methodologies. How are usability studies integrated into clinical investigations in practice?

METHODS

We searched the ClinicalTrials.gov database for clinical investigation protocols that included usability outcome(s) and analyzed them.

RESULTS

77 study protocols were identified for the analysis, including 102 outcomes related to usability in total. The most frequently assessed outcomes were satisfaction (53/102) and ease of use (33/102). The questionnaire was the most frequently planned technique (85/102) followed by interviews (24/102). Other methods were used, such as observation (9/102), mostly when the end users was a healthcare professional, and diary (6/102), mostly with patients.

CONCLUSION

Our study results showed that the collection of usability data can be included in a clinical investigation, with various levels of investment. Resource-light, rapid integration via a questionnaire will enable the collection of subjective data on the users' perceptions. When more resources are available, observation in accessible environments can be set up (especially during use by healthcare professionals in hospital) or interviews and/or diaries for home-based environments (especially by patients).

Frequencies and predictors of subcutaneous and intraosseous injection with 4 epinephrine autoinjector devices

BACKGROUND

To prevent anaphylaxis-associated illness, intramuscular epinephrine injection is recommended. Subcutaneous injection may reduce efficacy, and intraosseous injection promotes morbidity. A few studies suggested that commercially available thigh epinephrine autoinjectors (EAIs) may induce subcutaneous/intraosseous injection in some adults.

OBJECTIVE

To estimate the subcutaneous/intraosseous-injection rates of 4 EAIs by comparing their needle lengths with the ultrasound-measured skin-to-muscle depth and skin-to-bone depth of the midthigh of adults with allergic diseases in a cross-sectional study and to determine patient factors that predict subcutaneous EAI injection.

METHODS

Thigh ultrasound was conducted in a convenience-recruited cohort with minimal and maximal compression to estimate the effect of EAI-induced compression. Subcutaneous/intraosseous-injection rates were estimated for Anapen (BioProject), EpiPen (Mylan), Jext (ALK), and Emerade (Medeca). Multivariate analyses for subcutaneous-injection risk were conducted with age, male/female sex, abdominal and thigh circumferences, and upper-arm skinfold thickness.

RESULTS

A total of 68 patients were recruited. Compression thinned the subcutaneous tissue and muscle by 1 and 9 mm, respectively, on average. Projected subcutaneous-injection rates with/without compression were high for Anapen (65%-66%), moderate for EpiPen and Jext (29%-38%), and lowest for Emerade (13%-21%). Compression introduced a small intraosseous-injection risk with Emerade (4%). Female sex predicted subcutaneous injection (odds ratio, 1.3-2.0; all P < .001). Depending on the EAI, 29% to 97% of women and 0% to 41% of men would be injected subcutaneously. Older men were at risk of intraosseous Emerade injection. Obesity-related variables predicted subcutaneous injection poorly.

CONCLUSION

Anapen was associated with high subcutaneous-injection rates. EpiPen and Jext were projected to provide intramuscular injection in all men without risk of intraosseous injection. Emerade yielded the lowest subcutaneous-injection rates in women. Compression largely affected the muscle.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02886468.

Knowledge and attitudes toward anaphylaxis to local anesthetics in dental practice

OBJECTIVE/AIM

The absence of a comprehensive understanding of potential anaphylactic reactions to local anesthetics (LAs) and management can result in grave consequences. For this reason we aim to assess Latin American dentists' knowledge, preparedness, and competency in managing anaphylactic reactions to LAs.

MATERIALS AND METHODS

Design: A cross-sectional study was conducted from November 2021 to February 2022. Board-certified dentists answered a survey comprising 26 structured questions. Chi-square tests and logistic regression models were performed in Stata 17.0.

SETTING

Argentina, Brazil, Colombia, Costa Rica, Ecuador, Honduras, Mexico, Peru, Venezuela, and other Latin American countries.

RESULTS

Of 507 respondents, lidocaine was the most frequently used LA (88.1%). While 85.2% could identify dyspnea as a symptom of anaphylaxis, only 50.1% knew the correct route for epinephrine administration, and just 43.5% had epinephrine in their emergency kits. Confidence in managing anaphylactic reactions was low (9.6%). Older age was inversely related to both knowledge of anaphylaxis management and the possession of epinephrine (P = 0.003 and P = 0.0001, respectively).

DISCUSSION

Our study highlights a concerning discrepancy between the practical readiness of Latin American dentists in handling anaphylaxis.

CONCLUSION

The study's findings underscore the need for educational interventions to improve the readiness to identify and handle anaphylactic emergencies in dental practice.

The Reliability of Auto-Injectors in Clinical Use: A Systematic Review

Auto-injectors are medical devices designed for the self-administration of injections by patients and for easy administration by healthcare professionals in emergency situations. Although they vary in design and application, auto-injectors are typically built around a spring-loaded syringe. Despite their widespread use in a variety of clinical settings, there have been limited attempts to assess their reliability. This systematic review investigates the reliability of auto-injectors, identifies common causes of failure, and summarizes the overall rate of malfunction. A systematic review of research published on the PubMed and Cochrane Library databases was performed in July 2022. The relevant studies were assessed for their methodological quality and risk of bias prior to extracting key study outcomes on auto-injector reliability. Finally, a summary rate covering all eligible studies was calculated.  The search identified a total of 110 articles, of which ten were found to be suitable for inclusion. The risk of bias was low, and the methodological quality was high across the ten studies. Out of a total of 2,964 injections administered from an auto-injector, there were 12 device malfunctions, giving a summary rate of 0.40% (±0.23) auto-injector failures. The causes of malfunction varied in nature, with the majority of cases (58.3%) not being specified or not identified. This review has demonstrated that auto-injectors are reliable devices. Although further research on the nature of malfunctions is needed, the low rate of malfunctions supports training programs for healthcare professionals and patients on the optimum use and maintenance of auto-injectors. It provides a rationale for their continued development.

Formative and Validation Human Factors studies of a new disposable autoinjector for subcutaneous delivery of chronic disease therapies

BACKGROUND

Use-related risks related to autoinjector devices have been previously identified. To minimize these problems, the identification of potential use errors is a critical task during device development.

METHODS

This article presents iterative human factor studies, which aim to assess user interaction with the tested push-on-skin BD Intevia™ 1 mL Disposable Autoinjector, across a wide range of indications, and a broad user population.

RESULTS

Through the different human factor studies, use errors were recorded when the participants completed the critical tasks, but their occurrence continuously decreased. First, the incidence of use errors was reduced when the participants read the IFU. In addition, the IFU updates and design change implemented contributed to improve the usability performance. During the validation study, some use errors were still observed, mainly during the first uses. Nevertheless, providing a training to the participants almost fully eliminated the remaining use errors.

CONCLUSION

Thus, these results demonstrated that this new autoinjector can be safely and efficiently used for its intended uses and under the expected use conditions by all tested user groups.

Digital technology for anaphylaxis management impact on patient behaviour: A randomized clinical trial

BACKGROUND

Epinephrine is the first-line treatment for anaphylaxis. Patients at risk should always carry an epinephrine autoinjector (EAI). Several EAI gaps have been identified. We sought to evaluate satisfaction using a medical device (digital technology comprising an EAI smart case connected to a mobile APP) with functions that overcome most of the EAI limitations and to determine whether patient behaviour and anaphylaxis management improve with its use.

METHODS

This was a randomized, open-label, crossover clinical trial in a tertiary hospital involving patients with history of anaphylaxis carrying an EAI. The study was conducted in two three-month periods, one with and one without the medical device. The primary endpoint was satisfaction with the medical device. Usability, adherence, anxiety and anaphylaxis episodes were evaluated as secondary endpoints.

RESULTS

A total of 100 patients were included (mean age 38.1 years, 74% female), and 95 completed the trial. The satisfaction visual analogue scale (VAS) after using the medical device was higher than before its use (89.1 [95% CI, 60.2-99.1] vs 56.3 [95% CI, 48.1-81.4]; P < .0001). The adherence VAS improved from 59.7 (95% CI, 54.0-65.3) to 88.6 (95% CI, 84.2-92.9) (P < .0001). Overall, 90% patients found the medical device easy to use. Patients' anxiety decreased from 52.2% to 29.3% (P < .001). Seven episodes of anaphylaxis occurred during the study, all in patients without the medical device (P = .025). Eighty-eight per cent of patients felt more involved in the management of anaphylaxis when using the medical device.

CONCLUSION

This is the first clinical trial evaluating digital technology for EAIs, showing a change of behaviour in patients at risk of anaphylaxis, increasing satisfaction, improving adherence, and reducing anxiety, with good usability.

Performance characterization of spring actuated autoinjector devices for Emgality and Aimovig

Objective: Autoinjectors are a convenient and efficient way to self-administer subcutaneous injections of biopharmaceuticals. Differences in device mechanical design can affect the autoinjector functionality and performance. This study investigates the performance differences of two single-spring-actuated autoinjectors.Methods: We compare the performance between Emgality (120 mg/mL) and Aimovig (140 mg/mL) autoinjector devices from an engineering point of view at two test conditions: room (25 C[Formula: see text]) and storage (5 C[Formula: see text]) temperatures. We employ a novel experimental procedure to simultaneously acquire the force and acoustic signals during operation, and high-speed imaging during the needle insertion and drug injection.Results: We perform 18 quantitative comparisons between Emgality and Aimovig, and we observe that 14 of these have statistically significant differences. For both test conditions, Emgality requires an 8 N activation force while Aimovig requires 14 N activation force, and the needle of Emgality has an insertion depth of 5 mm while Aimovig has an insertion depth of 7 mm. The injection speeds are significantly affected by temperature. Emgality has an injection speed of 0.40 mL/s and 0.28 mL/s at room and storage temperature condition, respectively; while Aimovig has an injection speed of 0.24 mL/s and 0.16 mL/s at those conditions. Lastly, confirmation "click" sound of Emgality occurs 0.75-1.53 s after dose completion, while in Aimovig, the confirmation "click" sound occurs 0.26-0.46 s before dose completion.Conclusions: This study revealed performance differences between Emgality and Aimovig autoinjector devices, despite the fact that the delivery principle of these single-spring-actuated autoinjectors are the same. These differences may result in different risk of intramuscular injection and premature device removal, both of which need to be further verified in clinical trials.

Usability and preference of epinephrine auto-injectors: Auvi-Q and EpiPen Jr

BACKGROUND

Despite the importance of prompt epinephrine auto-injector (EAI) treatment during anaphylaxis, proper administration technique is often lacking among patients and caregivers.

OBJECTIVE

To compare usability and participant preference of Auvi-Q and EpiPen Jr EAIs in a simulated life-threatening allergic emergency-use scenario.

METHODS

In this randomized, crossover, human-factors usability study, untrained adults (18-65 years) were tasked with using 0.15 mg Auvi-Q and EpiPen Jr trainers to simulate epinephrine administration to a child-sized manikin. Only written instructions on the device label and/or device voice instructions were available to participants. Endpoints included completing injection tasks per device instructions (primary endpoint), completing key injection tasks, and participant preference/ratings of devices. Completion of injection tasks were evaluated using a McNemar test for paired dichotomous data.

RESULTS

Ninety-six adults were included in study analyses. Significantly more participants completed all injection tasks per device instructions with Auvi-Q (85.4%) vs EpiPen Jr (19.8%; P < .001). Significant differences were also observed for completion of key injection tasks (Auvi -Q, 94.8%; EpiPen Jr, 72.9%; P < .001). No digital/hand injection errors were seen with Auvi-Q, whereas 14 participants (14.6%) would have accidentally received a digital/hand injection with EpiPen Jr (P < .001). Overall, significantly more participants preferred Auvi-Q over EpiPen Jr (91.7% vs 6.3%; P < .001 [2.1% no preference]). Median scores for 8 EAI characteristics were also higher for Auvi-Q vs EpiPen Jr.

CONCLUSION

In this study, untrained adults preferred and were more likely to use Auvi-Q correctly vs EpiPen Jr, highlighting the importance of device design for successful epinephrine administration during a life-threatening allergic emergency.

Bioavailability and Cardiovascular Effects of Adrenaline Administered by Anapen Autoinjector in Healthy Volunteers

BACKGROUND

The administration of adrenaline is a life-saving intervention for anaphylactic reactions. However, it has been questioned whether the needle length of the autoinjectors is sufficient to achieve genuine intramuscular delivery and optimal bioavailability.

OBJECTIVE

To assess the adequacy of Anapen, which has a relatively short needle length (10.5 mm), through a comparison of the depot localization, plasma pharmacokinetics, and cardiovascular responses of adrenaline delivered via Anapen versus a prefilled syringe with a 25.4-mm needle, which is generally used for intramuscular injections.

METHODS

This randomized, open-label, crossover study compared the impact of adrenaline administration at 2 sites in the thigh of 18 normal weight male volunteers, using either Anapen or the prefilled syringe; in addition, we studied the treatment of 12 overweight women with Anapen. The depot depth was measured by ultrasonography, plasma adrenaline level was evaluated by ultra performance liquid chromatography-mass spectrometry (UPLC-MS), and heart rates were measured using a Holter monitor.

RESULTS

Intramuscular injections were given with both devices at both thigh sites in nonobese men, but not in overweight women. Adrenaline levels showed a double peak, with parallel changes in the heart rate. The first peak, of potential vital importance in anaphylaxis treatment, occurred at approximately 10 minutes postinjection, with maximum concentration and area under the curve significantly higher with Anapen than with prefilled syringes; the magnitude of the second peak did not differ among the various conditions. Unexpectedly, in overweight women treated with Anapen, the magnitude of the first peak was similar to that observed in men, despite the injection being subcutaneous, and the overall bioavailability was enhanced.

CONCLUSIONS

Needle length and intramuscular injection are not absolute requirements for autoinjector efficacy, but the monitoring of injection location, biphasic adrenaline levels, and cardiovascular responses is important for the assessment of their therapeutic relevance in anaphylaxis.

Update on the usage and safety of epinephrine auto-injectors, 2017

Anaphylaxis is a serious, potentially fatal allergic reaction. Guidelines recommend prompt intramuscular injections of epinephrine as the first-line therapy for anaphylaxis. Delayed epinephrine treatment may cause undesirable clinical outcomes, including death. In the community, epinephrine auto-injectors (EAIs) are commonly used to treat anaphylaxis. This literature review examines several recent concerns regarding the safety of EAIs that may prevent the timely administration of epinephrine. Reports of cardiovascular complications are linked with epinephrine administration, although recent studies suggest that these events are much more commonly associated with intravenous epinephrine rather than with EAIs. Recent studies have also highlighted accidental injections of EAIs in patients’ or caregivers’ fingers and lacerations associated with the use of EAI in children. However, the data suggest that both accidental injections and lacerations are rare and require limited medical intervention. In addition, patients may receive conflicting information on the safety and efficacy of using expired EAIs. Overall, it is believed that the benefits of using EAIs far outweigh the potential risks of not administering an EAI. Although legitimate safety concerns are associated with EAIs, adverse events are rare. Continued training of medical providers, caregivers, and patients may be beneficial to address these concerns and reduce EAI-associated injuries while ensuring that patients receive necessary medical care.

Autoinjectors Preferred for Intramuscular Epinephrine in Anaphylaxis and Allergic Reactions

INTRODUCTION

Epinephrine is the treatment of choice for anaphylaxis. We surveyed emergency department (ED) healthcare providers regarding two methods of intramuscular (IM) epinephrine administration (autoinjector and manual injection) for the management of anaphylaxis and allergic reactions and identified provider perceptions and preferred method of medication delivery.

METHODS

This observational study adhered to survey reporting guidelines. It was performed through a Web-based survey completed by healthcare providers at an academic ED. The primary outcomes were assessment of provider perceptions and identification of the preferred IM epinephrine administration method by ED healthcare providers.

RESULTS

Of 217 ED healthcare providers invited to participate, 172 (79%) completed the survey. Overall, 82% of respondents preferred the autoinjector method of epinephrine administration. Providers rated the autoinjector method more favorably for time required for training, ease of use, convenience, satisfaction with weight-based dosing, risk of dosing errors, and speed of administration (p<0.001 for all comparisons). However, manual injection use was rated more favorably for risk of provider self-injury and patient cost (p<0.001 for both comparisons). Three participants (2%) reported a finger stick injury from an epinephrine autoinjector.

CONCLUSION

ED healthcare providers preferred the autoinjector method of IM epinephrine administration for the management of anaphylaxis or allergic reactions. Epinephrine autoinjector use may reduce barriers to epinephrine administration for the management of anaphylaxis in the ED.

Self-medication of anaphylactic reactions due to Hymenoptera stings-an EAACI Task Force Consensus Statement

An anaphylactic reaction due to a Hymenoptera sting is a clinical emergency, and patients, their caregivers as well as all healthcare professionals should be familiar with its recognition and acute management. This consensus report has been prepared by a European expert panel of the EAACI Interest Group of Insect Venom Hypersensitivity. It is targeted at allergists, clinical immunologists, internal medicine specialists, pediatricians, general practitioners, emergency department doctors, and any other healthcare professional involved. The aim was to report the scientific evidence on self-medication of anaphylactic reactions due to Hymenoptera stings, to inform healthcare staff about appropriate patient self-management of sting reactions, to propose indications for the prescription of an adrenaline auto-injector (AAI), and to discuss other forms of medication. First-line treatment for Hymenoptera sting anaphylaxis is intramuscular adrenaline. Prescription of AAIs is mandatory in the case of venom-allergic patients who suffer from mast cell diseases or with an elevated baseline serum tryptase level and in untreated patients with a history of a systemic reaction involving at least two different organ systems. AAI prescription should also be considered in other specific situations before, during, and after stopping venom immunotherapy.

Lacerations and Embedded Needles Caused by Epinephrine Autoinjector Use in Children

STUDY OBJECTIVE

Epinephrine autoinjector use for anaphylaxis is increasing. There are reports of digit injections because of incorrect autoinjector use, but no previous reports of lacerations, to our knowledge. We report complications of epinephrine autoinjector use in children and discuss features of these devices, and their instructions for use, and how these may contribute to injuries.

METHODS

We queried emergency medicine e-mail discussion lists and social media allergy groups to identify epinephrine autoinjector injuries involving children.

RESULTS

Twenty-two cases of epinephrine autoinjector-related injuries are described. Twenty-one occurred during intentional use for the child's allergic reaction. Seventeen children experienced lacerations. In 4 cases, the needle stuck in the child's limb. In 1 case, the device lacerated a nurse's finger. The device associated with the injury was operated by health care providers (6 cases), the patient's parent (12 cases, including 2 nurses), educators (3 cases), and the patient (1 case). Of the 3 epinephrine autoinjectors currently available in North America, none include instructions to immobilize the child's leg. Only 1 has a needle that self-retracts; the others have needles that remain in the thigh during the 10 seconds that the user is instructed to hold the device against the leg. Instructions do not caution against reinjection if the needle is dislodged during these 10 seconds.

CONCLUSION

Epinephrine autoinjectors are lifesaving devices in the management of anaphylaxis. However, some have caused lacerations and other injuries in children. Minimizing needle injection time, improving device design, and providing instructions to immobilize the leg before use may decrease the risk of these injuries.

Population pharmacokinetic and pharmacodynamic modeling of epinephrine administered using a mobile inhaler

Inhaled epinephrine is a potential alternative to self-administered intramuscular epinephrine in imminent anaphylactic reactions. The objective was to develop a pharmacokinetic-pharmacodynamic model describing exposure and effects on heart rate of inhaled epinephrine. Data from a 4-phase cross-over clinical trial in 9 healthy volunteers including 0.3 mg intramuscular epinephrine, two doses of inhaled epinephrine (4 mg/mL solution administered during [mean] 18 and 25 min, respectively) using a mobile pocket inhaler, and an inhaled placebo were analyzed using mixed-effects modeling. Inhaled epinephrine was available almost immediately and more rapidly than via the intramuscular route (absorption half-live 29 min). Epinephrine plasma concentrations declined rapidly after terminating inhalation (elimination half-life 4.1 min) offering the option to stop exposure in case of adverse events. While the expected maximum concentration was higher for inhaled epinephrine, this was not associated with safety concerns due to only moderate additional hemodynamic effects compared to intramuscular administration. Bioavailability after inhalation (4.7%) was subject to high interindividual and interoccasional variability highlighting that training of inhalation would be essential for patients. The proposed model suggests that the use of a highly concentrated epinephrine solution via inhalation may offer an effective treatment option in anaphylaxis, while efficacy in patients remains to be shown.

Excess subcutaneous tissue may preclude intramuscular delivery when using adrenaline autoinjectors in patients with anaphylaxis

Intramuscular adrenaline is the gold standard treatment for anaphylaxis. Intramuscular injection provides more rapid and higher plasma concentrations than subcutaneous routes. Given the increasing epidemic of obesity patients are at increased risk of subcutaneous delivery, we therefore assessed the depth of subcutaneous tissue in a population of patients with anaphylaxis. Patients already prescribed adrenaline autoinjectors (AAIs) for anaphylaxis were examined with ultrasound, and measurements of skin-to-muscle depth (STMD) at anterolateral thigh and anterior thigh were performed. Twenty-eight patients (23 female, 5 male) with an age range of 18-75 took part in the study, and in 68%, the STMD was greater than AAI needle length (15.02 mm), using the anterolateral thigh as the recommended administration site. The key predictors for increased STMD were female gender (P=0.0003) and a BMI > 30 (P=0.04). AAIs require longer needles to ensure intramuscular administration, and ultrasound at point of prescription would aid needle length selection.

Comparison of adrenaline auto-injector devices: ease of use and ability to recall use

BACKGROUND

A limited number of adrenaline auto-injectors are currently available. Epipen and Anapen are available in Australia, New Zealand, UK and parts of Europe and Asia. Few studies have compared the performance of these devices.

OBJECTIVE

To compare the intuitiveness of use of these devices. A secondary aim was to compare the ability to recall the use of each device after a period of 3 months.

METHOD

A random sample of 100 subjects naïve to both the EpiPen and Anapen were recruited from staff and families attending Royal Children's Hospital, Melbourne Australia. Subjects were randomized to Anapen (n = 53) or EpiPen (n = 47) and asked to demonstrate use of a 'trainer' device (i) prior to and (ii) after receiving training in its correct use. A subset (n = 32) participated in a follow-up study to evaluate (iii) the ability to recall correct use of each device.

RESULTS

Most subjects correctly demonstrated all steps in use of the EpiPen and Anapen both prior to (89% vs. 79%, p = 0.17) and after training on use (100% vs. 100%). However, after 3 months, significantly more participants correctly demonstrated use of EpiPen (87%) compared to Anapen (35%) (p = 0.003) and critical errors that would likely result in failure to administer adrenaline were more common with Anapen (59% vs. 13%, p = 0.01).

CONCLUSION

Most study participants correctly demonstrated the use of both devices without prior training. There was greater attrition in correct use of Anapen compared to EpiPen over time. Critical errors in administration were more likely with Anapen than EpiPen.

Anaphylaxis treatment: current barriers to adrenaline auto-injector use

Anaphylaxis is a life-threatening condition that is increasing in prevalence in the developed world. There is universal expert agreement that rapid intramuscular injection of adrenaline is life-saving and constitutes the first-line treatment of anaphylaxis. The unpredictable nature of anaphylaxis and its rapid progression makes necessary the availability of a portable emergency treatment suitable for self-administration. Thus, anaphylaxis treatment guidelines recommend that at-risk patients are provided with adrenaline auto-injectors (AAIs). Despite these clear recommendations, current emergency treatment of anaphylaxis continues to be inadequate in many cases. The aim of this review is to highlight the barriers that exist to the use and availability of AAIs and that prevent proper management of anaphylaxis. In addition, we review the characteristics of all AAIs that are presently available in Europe and the USA and discuss the need for regulatory requirements to establish the performance characteristics of these devices.

New autoinjector technology for the delivery of subcutaneous methotrexate in the treatment of rheumatoid arthritis

Methotrexate (MTX) is the cornerstone of treatment for rheumatoid arthritis (RA), and is widely used both as first-line therapy and as an important component of long-term therapy. Although subcutaneous MTX is typically delivered orally, parenteral administration offers benefits with respect to tolerability and systemic exposure, and may be an underutilized treatment option. The RA patient population presents specific challenges for safe and accurate administration of parenteral therapies, because of common symptoms of joint pain and limited manual dexterity. These challenges may contribute to the low incidence of parenteral MTX administration. A novel MTX autoinjector (MTXAI) was recently introduced, which is designed to facilitate subcutaneous MTX self-administration among patients with RA. Here we review the development and utility of the MTXAI in the treatment of RA, and discuss how this technology may facilitate the use of subcutaneous MTX.

Bioavailability of epinephrine from Auvi-Q compared with EpiPen

BACKGROUND

Epinephrine autoinjectors are underused for the treatment of anaphylaxis in community settings. Auvi-Q, a novel epinephrine autoinjector, was designed to be intuitive to use and reduce the potential for use-related errors.

OBJECTIVE

To compare the bioavailability of 0.3 mg of epinephrine (adrenaline) injected with Auvi-Q and EpiPen in healthy adults.

METHODS

In this randomized, single-blind, 2-treatment, 3-period, 3-sequence crossover study, healthy adults (18-45 years old) received a single injection of 0.3 mg of epinephrine with Auvi-Q in one period and with EpiPen in the other 2 periods. Blood samples were obtained before and 14 times during 6 hours after the dose. Outcomes included peak plasma concentration (Cmax), total epinephrine exposure (area under the concentration-time curve [AUC] from baseline to the last measurable concentration [AUC0-t] and extrapolated to infinity [AUCinf]), and adverse events.

RESULTS

Seventy-one volunteers (53 male, 74.6%), with a mean age of 33.2 years and a mean body mass index of 25.4, were randomized. Epinephrine peak concentration and total exposure were similar between Auvi-Q (Cmax = 0.486 ng/mL; AUC0-t = 0.536 ng·h/mL; AUCinf = 0.724 ng·h/mL) and EpiPen (Cmax = 0.520 ng/mL; AUC0-t = 0.466 ng·h/mL; AUCinf = 0.583 ng·h/mL). Cmax and AUC analyses demonstrated bioequivalence between Auvi-Q and EpiPen. Most treatment-emergent adverse events were mild (98%), and all resolved spontaneously. Rates of injection-site pain and bleeding were 13% and 5%, respectively, for Auvi-Q vs 24% and 10%, respectively, for EpiPen.

CONCLUSION

After a single injection of 0.3 mg of epinephrine, Auvi-Q and EpiPen had similar peak and total epinephrine exposure, were bioequivalent, and had similar safety profiles.

Auvi-Q versus EpiPen: preferences of adults, caregivers, and children

BACKGROUND

Auvi-Q is a novel epinephrine autoinjector (EAI) that provides audio and visual cues for patients at risk for life-threatening allergic reactions.

OBJECTIVE

We tested the preference for Auvi-Q or EpiPen with regard to method of instruction, preference to carry, device size, and device shape.

METHODS

This large, multicenter, simulated-use study evaluated whether adults (aged 18-65 years), caregivers (parents/guardians aged 18-65 years of children aged 5-17 years), and children (aged 11-17 years), with and without experience in using an EAI, had a preference for the current design of Auvi-Q or the current design of EpiPen. Participants were given a scenario that involved anaphylaxis and were instructed to simulate use of an EAI. They received and tested each device individually according to the randomization assignment. After testing both devices, they completed a survey to indicate their preference for Auvi-Q versus EpiPen.

RESULTS

Among all 693 participants combined, Auvi-Q was preferred over EpiPen on all study end points (P < .001). For experienced and inexperienced participants in all 3 groups (adults, caregivers, and children), Auvi-Q was preferred over EpiPen for method of instruction, preference to carry, and device size (all P < .001). The preference for Auvi-Q device shape was not significant among experienced children (P = .10); however, it was significant for inexperienced children (P = .04) and highly significant for experienced and inexperienced adults and caregivers (P < .001).

CONCLUSION

In this large multicenter, simulated-use study, Auvi-Q was preferred over EpiPen by experienced and inexperienced adults, caregivers, and children.

Design validation and labeling comprehension study for a new epinephrine autoinjector

BACKGROUND

To facilitate the correct use of epinephrine autoinjectors (EAIs) by patients and caregivers, a novel EAI (Auvi-Q) was designed to help minimize use-related hazards.

OBJECTIVE

To support validation of Auvi-Q final design and assess whether the instructions for use in the patient information leaflet (PIL) are effective in training participants on proper use of Auvi-Q.

METHODS

Healthy participants, 20 adult and 20 pediatric, were assessed for their ability to complete a simulated injection by following the Auvi-Q instructions for use. Participants relied only on the contents of the PIL and other labeling features (device labeling and its instructions for use, electronic voice instructions and visual prompts).

RESULTS

The mean ± SD age of the adult and pediatric participants was 39.4 ± 11.6 and 10.9 ± 2.3 years, respectively. In total, 80% of adult and 35% of pediatric participants had prior experience with EAIs. All adults and 95% of pediatric participants completed a simulated injection on the first attempt; 1 pediatric participant required parental training and a second attempt. Three adult and 4 pediatric participants exhibited a noncritical issue while successfully completing the simulated injection. Most participants agreed that the injection steps were easy to follow and the PIL facilitated understanding on using Auvi-Q safely and effectively.

CONCLUSION

The PIL and other labeling features were effective in communicating instructions for successful use of Auvi-Q. This study provided validation support for the final design and anticipated instructions for use of Auvi-Q.

Pharmacokinetics and pharmacodynamics of moist inhalation epinephrine using a mobile inhaler

BACKGROUND

Intramuscular (L-)epinephrine is used as self-medication for serious hypersensitivity reactions. Inhalative administration has the theoretical advantage of a more rapid absorption and better controllability.

OBJECTIVES

The current trial was conducted to explore pharmacokinetics and pharmacodynamics of two nebulized inhalative epinephrine doses (4 mg and 8 mg in aqueous solution) using a mobile pocket inhaler relative to intramuscular administration (0.3 mg) and placebo.

METHODS

This randomized, open-label, change-over pilot study involved eight young healthy men and women. Noncompartmental pharmacokinetic and pharmacodynamic parameters were calculated from epinephrine plasma concentrations and hemodynamic parameters.

RESULTS

Mean exposure to epinephrine decreased from the 8 mg dose to the 4 mg inhalative dose, and further with the 0.3 mg intramuscular dose, with active treatments showing significantly higher concentrations than placebo (geometric mean area under the curve AUC0-t(last) values: 282, 236, 204 and 81.6 hr*ng/L). Maximal concentrations were reached within approximately 15 min for all active treatments. Epinephrine effects for inhalative administrations on heart rates were significantly higher than those for the intramuscular or placebo administration, while no excessive effects occurred. Pronounced overall variability prohibited a definite assessment of relative bioavailability between treatments. However, results indicated that epinephrine concentrations obtained following the 8 mg inhalative dose were not inferior to those after 0.3 mg i.m.

CONCLUSIONS

A relevant fraction of moist inhalation epinephrine doses is absorbed and mediates systemic effects. This suggests that administration of epinephrine via a suitable pocket inhaler device may be beneficial in ambulatory emergency treatment of systemic hypersensitivity reactions. EudraCT number: 2010-021493-11.

Intelligent drug-delivery devices based on micro- and nano-technologies

This review focuses on the current drug-delivery modalities in R&D, as well as commercially available. Intelligent drug-delivery systems are described as novel technological innovations and clinical approaches to improve conventional treatments. These systems differ in methodology of therapeutic administration, intricacy, materials and patient compliance to address numerous clinical conditions that require various pharmacological therapies. These systems have been primarily described as active and passive microelectrical mechanical system devices, injectors and nanoparticle-based therapies, optimized to tailor specific pharmacokinetic profiles. The most critical considerations for the design of these intelligent delivery systems include the controlled release, target specificity, on-demand dosage adjustment, mass transfer and stability of the pharmacological agents. Drug-delivery systems continue to be developed and enhanced to provide better and more sophisticated treatments, promising an improvement in quality of life and extension of life expectancy.

Preventive and therapeutic effects of rapamycin, a mammalian target of rapamycin inhibitor, on food allergy in mice

BACKGROUND

Because few curative treatments are available for food allergy, we investigated the therapeutic potential of rapamycin, a mammalian target of rapamycin (mTOR) inhibitor, on mouse food allergy.

METHODS

The preventive and therapeutic effects of oral rapamycin on anaphylactic symptoms induced by oral ovalbumin (OVA) challenge in food allergy mice were investigated. Mast cell functions in response to rapamycin were also measured in the passive systemic anaphylaxis model and bone marrow-derived mast cells (BMMCs).

RESULTS

Daily rapamycin from the first challenge (preventive protocol) attenuated food allergy symptoms including diarrhea, anaphylactic reactions, and hypothermia in mice. The treatment decreased the challenge-induced increases in mouse mast cell protease-1 in serum and mast cell numbers in the intestine. Notably, the mice that already showed food allergy symptoms by previous challenges recovered from the disease with daily administration of rapamycin (therapeutic protocol). Anti-OVA IgG1 and IgE levels in serum, as well as IFN-γ, IL-4, IL-13, IL-9, IL-10, and IL-17 secretion from splenocytes, were decreased by the treatments. In contrast, a single dose of rapamycin failed to affect passive systemic anaphylaxis. Spontaneous and IL-9-dependent survival and IgE-induced IL-13 secretion, but not degranulation, of BMMCs were reduced by rapamycin.

CONCLUSION

Our data show that mouse food allergy was attenuated by rapamycin through an immunosuppressive effect and inhibition of intestinal mast cell hyperplasia. Inhibition of the IL-9 production-mast cell survival axis is one of the mechanisms of the therapeutic effect of rapamycin. Rapamycin and other mTOR inhibitors might be good candidates for therapeutic drugs for food allergy.

Comparison of the robustness and functionality of three adrenaline auto-injectors

BACKGROUND

Anaphylaxis is a medical emergency that requires the intramuscular injection of adrenaline using an adrenaline auto-injector (AAI). This study compared the robustness and performance characteristics of three AAIs available in Europe.

METHODS

Three AAIs (Jext(®), EpiPen(®), and Anapen(®)) were tested in terms of the force needed to activate the AAIs, exposed needle length, injection volume, and injection time. Three conditions were used to assess robustness: base conditions, after three successive free-fall drops from 1.5 m, and after a 40 kg static load challenge. The injection depth and estimated volume of solution delivered into ballistic gelatin were also assessed.

RESULTS

Less force was required to remove the safety cap from Jext and EpiPen than from Anapen under base conditions. The required force was unaffected by free-fall drop tests, whereas the static load test significantly increased the force required to remove the safety cap from Jext (difference from base value 7.7 N; P < 0.001) and from EpiPen ( difference from base value 30.3 N; P < 0.001). Two Anapens could not be activated after the free-fall and static load tests. The mean exposed needle length was 15.36 mm (standard error [SE] 0.04) for Jext, 15.02 mm (SE 0.05) for EpiPen, and 7.49 mm (SE 0.15) for Anapen. The mean maximum injection depth in gelatin within 10 seconds was 28.87 mm (standard deviation [SD] 0.73) for Jext, 29.68 mm (SD 2.08) for EpiPen, and 18.74 mm (SD 1.25) for Anapen.

CONCLUSION

A comparison of the robustness and performance characteristics of the three AAIs showed that cartridge-based devices (Jext and EpiPen) appeared to be significantly more robust and capable of rapidly and consistently delivering the correct dose of adrenaline to the correct tissue compartment than the syringe-based Anapen. Overall, Jext performed better than EpiPen or Anapen following mechanical stress designed to mimic real-world use.

Adrenaline auto-injectors for the treatment of anaphylaxis with and without cardiovascular collapse in the community

BACKGROUND

Anaphylaxis is a serious hypersensitivity reaction that is rapid in onset and may cause death. Adrenaline (epinephrine) auto-injectors are recommended as the initial, potentially life-saving treatment of choice for anaphylaxis in the community, but they are not universally available and have limitations in their use.

OBJECTIVES

To assess the effectiveness of adrenaline (epinephrine) auto-injectors in relieving respiratory, cardiovascular, and other symptoms during episodes of anaphylaxis that occur in the community.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 1), MEDLINE (Ovid SP) (1950 to January 2012), EMBASE (Ovid SP) (1980 to January 2012 ), CINAHL (EBSCO host) (1982 to January 2012 ), AMED (EBSCO host) (1985 to January 2012 ), LILACS, (BIREME) (1980 to January 2012 ), ISI Web of Science (1950 to January 2012 ). We adapted our search terms for other databases. We also searched websites listing on-going trials: the World Health Organization International Clinical Trials Registry Platform, the UK Clinical Research Network Study Portfolio, and the meta Register of Controlled Trials; and contacted pharmaceutical companies who manufacture adrenaline auto-injectors in an attempt to locate unpublished material.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing auto-injector administration of adrenaline with any control including no intervention, placebo, or other adrenergic agonists were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed articles for inclusion.

MAIN RESULTS

None of the 1328 studies that were identified satisfied the inclusion criteria.

AUTHORS' CONCLUSIONS

Based on this review, we cannot make any new recommendations on the effectiveness of adrenaline auto-injectors for the treatment of anaphylaxis. Although randomized, double-blind, placebo-controlled clinical trials of high methodological quality are necessary to define the true extent of benefits from the administration of adrenaline in anaphylaxis via an auto-injector, such trials are unlikely to be performed in individuals experiencing anaphylaxis because of ethical concerns associated with randomization to placebo. There is, however, a need to consider trials in which, for example, auto-injectors of different doses of adrenaline and differing devices are compared in order to provide greater clarity on the dose and device of choice. Such trials would be practically challenging to conduct. In the absence of appropriate trials, we recommend that adrenaline administration by auto-injector should still be regarded as the most effective first-line treatment for the management of anaphylaxis in the community. In countries where auto-injectors are not commonly used, it may be possible to conduct trials to compare administration of adrenaline via auto-injector with adrenaline administered by syringe and ampoule, or comparing the effectiveness of two different types of auto-injector.

Part 2

Management of food allergy on a daily basis is multifaceted, time consuming, costly, and becomes compounded when multiple food allergies are involved. Allergen avoidance methodologies, monitoring of signs/symptoms of allergic reactions, handling serious medication needs, and planning ahead for a potential emergency due to an accidental exposure can be demanding concerns to the patient/family. Due to the complexity of this diagnosis, its implications to health-related quality of life, and extensive patient/family informational needs, it was necessary to divide this article into a 2-part series. This is the second article of the series. The content of Part 1 of the series focused on patient education associated with common food allergens, food allergy avoidance (eg, allergen identification, ingredient label reading, hidden allergens, cross-contact, precautionary labeling, potential routes of accidental exposures) and the food allergy action plan. Part 2 of the series reviews food-induced anaphylaxis and associated patient educational interventions (eg, use of self-injectable epinephrine, medical identification). Both parts of the series consider developmental concerns of the food allergic young child and adolescent. Parts 1 and 2 should be read collectively to acquire a complete view of suggested patient education for the newly diagnosed food hypersensitive pediatric patient and the role of a food allergy educator in an ambulatory care setting.

What factors affect the carriage of epinephrine auto-injectors by teenagers?

Background

Teenagers with allergies are at particular risk of severe and fatal reactions, but epinephrine auto-injectors are not always carried as prescribed. We investigated barriers to carriage.

Methods

Patients aged 12-18 years old under a specialist allergy clinic, who had previously been prescribed an auto-injector were invited to participate. Semi-structured interviews explored the factors that positively or negatively impacted on carriage.

Results

Twenty teenagers with food or venom allergies were interviewed. Only two patients had used their auto-injector in the community, although several had been treated for severe reactions in hospital. Most teenagers made complex risk assessments to determine whether to carry the auto-injector. Most but not all decisions were rational and were at least partially informed by knowledge. Factors affecting carriage included location, who else would be present, the attitudes of others and physical features of the auto-injector. Teenagers made frequent risk assessments when deciding whether to carry their auto-injectors, and generally wanted to remain safe. Their decisions were complex, multi-faceted and highly individualised.

Conclusions

Rather than aiming for 100% carriage of auto-injectors, which remains an ambitious ideal, personalised education packages should aim to empower teenagers to make and act upon informed risk assessments.

Make-up of the epinephrine autoinjector: the effect on its use by untrained users

BACKGROUND

Part of the problems related to proper use of the epinephrine autoinjector may be related to the design of the autoinjector itself.

AIM

We investigated whether minor modifications in the design of the currently available epinephrine autoinjector ease its use and abrogate common use errors.

METHODS

All interns other than those who had previously worked in allergy department in a medical school were invited to the study. Two identical epinephrine autoinjector trainers (Epipen trainer(®) ) were used, one of which was modified by changing the gray safety cap to red and placing a yellow arrow pointing to the black injection tip. A written and visual instruction sheet for each trainer was provided. Participants were asked to demonstrate the use of the Epipen trainer either with the original or with the modified one. They were scored and timed for their demonstration.

RESULTS

Out of the 224 interns who were invited to participate, one hundred and sixty-four interns (73.2%) participated in the study. The number of participants correctly demonstrating the use of epinephrine autoinjectors was 22.6% and 65% in unmodified and modified trainer groups, respectively (p < 0.001). The mean time to administer trainers was 26.78 ± 10.6 and 15.88 ± 2.55 s; total median scores were 3.08 ± 1.48 and 4.47 ± 0.84 in unmodified and modified groups, respectively (p < 0.001 for both). Significantly fewer participants had presumptive unintentional injection injury while using modified (5%) compared with unmodified trainer (45.2%) (p < 0.001).

CONCLUSION

Few and simple modifications in the design of epinephrine autoinjector were found effective in increasing its correct use and decreasing common use errors by untrained users. (Clinical trials identifier: NCT01217138).

Anaphylaxis pathogenesis and treatment

Anaphylaxis is a serious allergic reaction that is rapid in onset and sometimes leads to death. Understanding mechanisms, triggers, and patient-specific risk factors for severe or fatal anaphylaxis is critically important. Diagnosis of anaphylaxis is currently based on established clinical criteria. Epinephrine (adrenaline) is the first-line medication for anaphylaxis treatment and delay in injecting it contributes to biphasic reactions, hypoxic-ischemic encephalopathy, and fatality. Here, we focus on four important areas of translational research in anaphylaxis: studies of potential new biomarkers to support the clinical diagnosis of anaphylaxis, laboratory tests to distinguish allergen sensitization from clinical risk of anaphylaxis, the primary role of epinephrine (adrenaline) in anaphylaxis treatment, and strengthening the overall evidence base for anaphylaxis treatment.

Epinephrine auto-injector use in adolescents at risk of anaphylaxis: a qualitative study in Scotland, UK

BACKGROUND

Adolescents with severe allergies are at particular risk of severe and fatal anaphylactic reactions. Epinephrine (adrenaline) is known to be under-utilized by teenagers.

OBJECTIVE

We sought to gain knowledge of adolescents' attitudes towards and experience of epinephrine auto-injectors in order to inform improvements in patient education.

METHODS

A qualitative study of adolescents in Scotland, UK with a history of anaphylaxis and their parents. In-depth interviews explored adolescents' accounts of anaphylactic reactions, including issues related to using epinephrine auto-injectors. Focus groups with adolescents and parents were used to discuss interventions to improve adolescent self-management of anaphylaxis.

RESULTS

Twenty-six adolescents and 28 parents were interviewed. Eight adolescents and 10 parents participated in separate focus groups. Most adolescents had not used the auto-injector in an anaphylactic emergency. We identified multi-faceted barriers to use, including: failure to recognize anaphylaxis; uncertainty about auto-injector technique and when to administer it; fear of using the auto-injector. Most adolescents reported carrying auto-injectors some of the time, though several found this inconvenient due to the size; only one reported non-use of an auto-injector because it had not been carried.

CONCLUSION AND CLINICAL RELEVANCE

Adolescents and parents reported under-use of epinephrine auto-injectors. Carriage is insufficient to ensure that auto-injectors are used. Barriers to use are multiple and complex, and unlikely to be overcome using simple educational interventions. Auto-injector training currently offered is often inadequate preparation for an emergency. A more comprehensive approach is needed, addressing the psychosocial dimensions of anaphylactic emergencies as well as treatment. Training should ideally be provided by specialist allergists or nurses, but can also be provided and reinforced in primary care.

Are adrenaline autoinjectors fit for purpose? A pilot study of the mechanical and injection performance characteristics of a cartridge-versus a syringe-based autoinjector

Background:

Adrenaline autoinjectors (AAIs) are prescribed to facilitate the intramuscular administration of adrenaline in patients diagnosed with life-threatening anaphylaxis. This pilot study investigated the injection and functional properties of two AAIs (deploying different delivery systems) under standard conditions, after dynamic and mechanical stresses, and in the presence of denim.

Methods:

The differences between a cartridge-based AAI (EpiPen^® Junior) and a syringe-based AAI (Anapen^® Junior) were assessed using three sets of tests. Test 1: under standard conditions, the injection depth and dose were measured in ballistic gelatine (a validated tissue simulant). Test 2: before the safety cap removal and activation forces were measured, AAIs were subjected to either of two preconditioning tests: 1) free-fall drop test; or 2) static load (ie, 400 N, equivalent to 40 kg weight) test; or 3) no preconditioning. Test 3: under standard conditions, injection properties into ballistic gelatine in the presence and absence of denim were investigated. Statistical analyses were performed using the Student’s t-test or Welch’s test.

Results:

The maximum depth of delivery was significantly greater with cartridge AAI (n = 4, mean 21.09 ± 2.54 mm) than with syringe AAI (n = 5; mean 11.64 ± 0.80 mm; P = 0.003). After 2.5 seconds, cartridge AAI (n = 4) discharged significantly more dose than syringe AAI (n = 3; 74.3% versus 25.7% of total dose; P = 0.001). Both cartridge and syringe AAI withstood the free-fall drop test, but almost all devices failed to activate following the static load test. Under standard conditions, significantly less force was required to remove the safety cap of cartridge AAI than syringe AAI (both n = 15; mean 9.56 ± 2.36 N versus 20.23 ± 6.61 N, respectively; P < 0.001), but a significantly greater activation force was required for cartridge AAI than syringe AAI (mean 23.01 ± 3.96 N versus 8.06 ± 0.51 N, respectively; P < 0.001). The presence of denim did not alter the activation force or effective needle length of either of the AAIs.

Conclusion:

Cartridge AAI appears significantly more capable of consistently and rapidly delivering a clinically relevant dose of intramuscular adrenaline than syringe AAI. However, both devices showed shortcomings in their ability to sustain mechanical stress similar to that which is likely over their shelf life, and as such, may not be fit for life-saving purpose.