Needle-free Jet Injection Research Articles

Delivery of immunoreactive antigen using a controllable needle-free jet injector

Intradermal immunization of mice against hepatitis B surface antigen (HBsAg) using a novel real-time controlled jet injector was assessed by comparison with intradermal and subcutaneous injection of antigen using a 27G needle and syringe. Three doses of aluminium-absorbed HBsAg were delivered at 0, 14, and 28days. Antibodies to HBsAg were detected only in mice injected with antigen with antibody levels increasing with secondary injections. Mice vaccinated by intradermal injection using the jet injector or subcutaneous needle injection exhibited comparable immune responses at day 47. Differences in titer observed between intradermal jet injected and needle injected animals reflect differences in the volume of antigen delivered. With the exception of minor bleeding at the injection site in a few animals injected either by jet injection or needle, no adverse events were observed in any of the mice used in the study.

A New Concept of Needle-Free Jet Injector by the Impact Driven Method

Currently, most of commercial needle-free jet injectors generate the liquid jet by a method called “driving object method” (DOM); however, the reliability and efficiency are still questioned. This paper proposes a new concept of jet generation method, known as “impact driven method” (IDM). A prototype of an IDM jet injector is designed, built, tested, and compared to a commercial device (Cool.click, Tigard, OR). Fundamental characteristics, i.e., the exit jet velocity and impact pressure, are measured. Jet injection processes are visualized both in air and in 20% polyacrylamide by high speed photography. In this study, from the prototype of the IDM jet injector, a maximum jet velocity of 400 m/s and impact peak pressure of 68 MPa can be obtained. It is clear that the IDM jet injector provides a double pulsed liquid jet, which is a major advantage over the commercial jet injector. Because, the first pulse gives a shorter erosion stage, and then, immediately the second pulse follows and provides a better penetration, wider lateral dispersion, and considerably less back splash. Hence, lower pain level and higher delivery efficiency should be achieved. It can be concluded that the IDM concept is highly feasible for implementation in real applications, either for human or animal injection. However, the control and accuracy of IDM still needs to be carefully investigated.

A device for controlled jet injection of large volumes of liquid.

We present a needle-free jet injection device controllably actuated by a voice coil and capable of injecting up to 1.3 mL. This device is used to perform jet injections of ~900 μL into porcine tissue. This is the first time that delivery of such a large volume has been reported using an electronically controllable device. The controllability of this device is demonstrated with a series of ejections where the desired volume is ejected to within 1 % during an injection at a predetermined jet velocity.

Needle-free jet injection of intact phospholipid vesicles across the skin: a feasibility study.

Needle-free liquid jet injectors are devices developed for the delivery of pharmaceutical solutions through the skin. In this paper, we investigated for the first time the ability of these devices to deliver intact lipid vesicles. Diclofenac sodium loaded phospholipid vesicles of two types, namely liposomes and transfersomes, were prepared and fully characterized. The lipid vesicles were delivered through a skin specimen using a jet injector and the collected samples were analyzed to assess vesicle structural integrity, drug retention and release kinetics after the injection. In this regard, data concerning size, size distribution, surface charge of vesicles and bilayer integrity and thickness, before and after the injections, were measured by dynamic light scattering experiments, cryo-electron microscopy, and X-ray scattering techniques. Finally, the effect of vesicle fast jet injection through the skin on drug release kinetics was checked by in vitro experiments. The retention of the morphological, physico-chemical, and technological features after injection, proved the integrity of vesicles after skin crossing as a high-speed liquid jet. The delivery of undamaged vesicular carriers beneath the skin is of utmost importance to create a controlled release drug depot in the hypoderm, which may be beneficial for several localized therapies. Overall results reported in this paper may broaden the range of application of liquid jet injectors to lipid vesicle based formulations thus combining beneficial performance of painless devices with those of liposomal drug delivery systems.

Lispro administered by the QS-M Needle-Free Jet Injector generates an earlier insulin exposure

ABSTRACTObjective: The aim of this study is to evaluate the pharmacokinetic and pharmacodynamic (PK-PD) profiles of lispro administered by the QS-M needle-free jet injector in Chinese subjects.Research design and methods: A randomized, double-blind, double-dummy, cross-over study was performed. Eighteen healthy volunteers were recruited. Lispro (0.2 units/kg) was administered by the QS-M needle-free jet injector or by conventional pen. Seven-hour euglycemic clamp tests were performed.Results: A larger area under the curve (AUCs) of insulin concentration and glucose infusion rate (GIR) during the first 20 minutes after lispro injection by the jet injector compared to the insulin pen was observed (24.91 ± 15.25 vs. 12.52 ± 7.60 mg. kg−1, P < 0.001 for AUCGIR,0–20 min; 0.36 ± 0.24 vs. 0.10 ± 0.04 U min L−1, P < 0.001 for AUCINS, 0–20 min). Needle-free injection showed a shorter time to reach maximum insulin concentration (37.78 ± 11.14 vs. 80.56 ± 37.18 min, P < 0.001) and GIR (73.24 ± 29.89 vs. 116.18 ± 51.89 min, P = 0.006). There were no differences in total insulin exposure and hypoglycemic effects between the two devices.Conclusion: Lispro administered by QS-M needle-free injector results in earlier and higher insulin exposure than conventional pen, and a greater early glucose-lowering effect with similar overall potency.

Needle-free jet injection of hyaluronic acid improves skin remodeling in a mouse model

PurposeThe purpose of this study was to improve methods of jet injection using a mouse model. We investigated the mechanism of action, efficacy, and safety of the pneumatic device using injection of hyaluronic acid (HA) solution into a mouse model. MethodsWe evaluated the efficacy and safety of an INNOJECTOR™ pneumatic device that pneumatically accelerates a jet of HA solution under high pressure into the dermis of mouse skin. We examined the treatment effects using skin hybrid model jet dispersion experiments, photographic images, microscopy, and histological analyses. ResultsUse of the INNOJECTOR™ successfully increased dermal thickness and collagen synthesis in our mouse model. Jet dispersion experiments were performed using agarose gels and a polyacrylamide gel model to understand the dependence of jet penetration on jet power. The mechanisms by which pneumatic injection using HA solution exerts its effects may involve increased dermal thickening, triggering of a wound healing process, and activation of vimentin and collagen synthesis. ConclusionsCollagen synthesis and increased dermal thickening were successfully achieved in our mouse model using the INNOJECTOR™. Pneumatic injection of HA under high pressure provides a safe and effective method for improving the appearance of mouse skin. Our findings indicate that use of the INNOJECTOR™ may induce efficient collagen remodeling with subsequent marked dermal layer thickening by targeting vimentin.

Investigation of Hybrid Adaptive Control Schemes for Needle Free Jet Injection System

Investigation of Hybrid Adaptive Control Schemes for Needle Free Jet Injection System

Adaptive controller for a needle free jet-injector system.

A nonlinear, sliding mode adaptive controller was created for a needle-free jet injection system. The controller was based on a simplified lumped-sum parameter model of the jet-injection mechanics. The adaptive control scheme was compared to a currently-used Feed-forward+PID controller in both ejection of water into air, and injection of dye into ex-vivo porcine tissue. The adaptive controller was more successful in trajectory tracking and was more robust to the biological variations caused by a tissue load.

Needle-free jet injector intradermal delivery of fractional dose inactivated poliovirus vaccine: Association between injection quality and immunogenicity

IntroductionThe World Health Organization recommends that as part of the polio end-game strategy a dose of inactivated poliovirus vaccine (IPV) be introduced by the end of 2015 in all countries currently using only oral poliovirus vaccine (OPV). Administration of fractional dose (1/5 of full dose) IPV (fIPV) by intradermal (ID) injection may reduce costs, but its conventional administration is with Bacillus Calmette-Guerin (BCG) needle and syringe (NS), which is time consuming and technically challenging. We compared injection quality achieved with BCG NS and three needle-free jet injectors and assessed ergonomic features of the injectors. MethodsChildren between 12 and 20 months of age who had previously received OPV were enrolled in the Camaguey, Cuba study. Subjects received a single fIPV dose administered intradermally with BCG NS or one of three needle-free injector devices: Bioject Biojector 2000® (B2000), Bioject ID Pen® (ID Pen), or PharmaJet Tropis® (Tropis). We measured bleb diameter and vaccine loss as indicators of ID injection quality, with desirable injection quality defined as bleb diameter ≥5mm and vaccine loss <10%. We surveyed vaccinators to evaluate ergonomic features of the injectors. We further assessed the injection quality indicators as predictors of immune response, measured by increase in poliovirus neutralizing antibodies in blood between day 0 (pre-IPV) and 21 (post-vaccination). ResultsDelivery by BCG NS and Tropis resulted in the highest proportion of subjects with desirable injection quality; health workers ranked Biojector2000 and Tropis highest for ergonomic features. We observed that vaccine loss and desirable injection quality were associated with an immune response for poliovirus type 2 (P=0.02, P=0.01, respectively). ConclusionsOur study demonstrated the feasibility of fIPV delivery using needle-free injector devices with high acceptability among health workers. We did not observe the indicators of injection quality to be uniformly associated with immune response.

A needle-free technique for interstitial fluid sample acquisition using a lorentz-force actuated jet injector

We present a novel method of quickly acquiring dermal interstitial fluid (ISF) samples using a Lorentz-force actuated needle-free jet injector. The feasibility of the method is first demonstrated on post-mortem porcine tissue. The jet injector is used to first inject a small volume of physiological saline to breach the skin, and the back-drivability of the actuator is utilized to create negative pressure in the ampoule and collect ISF. The effect of the injection and extraction parameters on sample dilution and extracted volumes is investigated. A simple finite element model is developed to demonstrate why this acquisition method results in faster extractions than conventional sampling methods. Using this method, we are able to collect a sample that contains up to 3.5% ISF in 3.1s from post-mortem skin. The trends revealed from experimentation on post-mortem skin are then used to identify the parameters for a live animal study. The feasibility of the acquisition process is successfully demonstrated using live rats; the process is revealed to extract samples that have been diluted by a factor of 111–125.

The use of the needle-free jet injection system with buffered lidocaine device does not change intravenous placement success in children in the emergency department.

The needle-free jet injection system with buffered lidocaine (J tip) has been shown to reduce pain for intravenous (IV) line insertion, but its relationship with successful IV placement has not been well studied. This study aimed to determine if J tip use is associated with improved first-attempt IV placement success in children. This was a retrospective cohort study of children ages 1 to 18 years with need for emergent IV placement. Approximately 300 children were selected from each of three separate age groups: 1 to 2, 3 to 6, and 7 to 18 years. The standard treatment group (no device) included children with IV insertions from January 2009 through January 2010 with no J tip. The J tip treatment group (device) included children with IV insertions from December 2010 through December 2011 who received J tips. Successful IV placement on first attempt was the primary outcome. A chi-square test was used to compare the proportion of first-attempt success and logistic regression was performed to assess the effect of device use and patient age, sex, and race on first-attempt success. A total of 958 children were identified, 501 in the no-device group and 457 in the device group. The most common diagnoses were vomiting or dehydration (30.3%), trauma or burn (20.0%), and infection (15.5%). Overall, first-attempt success was 69.0% and was similar between the no-device (68.7%) and device (69.4%) groups (p = 0.81). No difference in first-attempt success with the use of the device was found in any of the age groups. Multivariate analysis found that only age of 1 to 2 years was associated with lower odds of first-attempt success when controlling for patient characteristics and device use. The use of the J tip did not affect first-attempt success for IV placement in children.

DNA vaccine-derived human IgG produced in transchromosomal bovines protect in lethal models of hantavirus pulmonary syndrome.

Polyclonal immunoglobulin-based medical products have been used successfully to treat diseases caused by viruses for more than a century. We demonstrate the use of DNA vaccine technology and transchromosomal bovines (TcBs) to produce fully human polyclonal immunoglobulins (IgG) with potent antiviral neutralizing activity. Specifically, two hantavirus DNA vaccines [Andes virus (ANDV) DNA vaccine and Sin Nombre virus (SNV) DNA vaccine] were used to produce a candidate immunoglobulin product for the prevention and treatment of hantavirus pulmonary syndrome (HPS). A needle-free jet injection device was used to vaccinate TcB, and high-titer neutralizing antibodies (titers >1000) against both viruses were produced within 1 month. Plasma collected at day 10 after the fourth vaccination was used to produce purified α-HPS TcB human IgG. Treatment with 20,000 neutralizing antibody units (NAU)/kg starting 5 days after challenge with ANDV protected seven of eight animals, whereas zero of eight animals treated with the same dose of normal TcB human IgG survived. Likewise, treatment with 20,000 NAU/kg starting 5 days after challenge with SNV protected immunocompromised hamsters from lethal HPS, protecting five of eight animals. Our findings that the α-HPS TcB human IgG is capable of protecting in animal models of lethal HPS when administered after exposure provides proof of concept that this approach can be used to develop candidate next-generation polyclonal immunoglobulin-based medical products without the need for human donors, despeciation protocols, or inactivated/attenuated vaccine antigen.

Optimal voice coil actuators for needle-free jet injection.

We present a scaling model for electrically-actuated needle free jet injectors, establishing the relationship between injection volume and motor size. Using an analytical electromagnetic model for the motor, we derive an optimal motor design, and show that this design is approximately scale-invariant. To illustrate the utility of this model, we then describe the design of a motor for use with 300 μL disposable injection ampoules with a mass of just 300 g, including a light-weight support structure. Experimental verification of the motor performance shows close agreement to model predictions, with a peak force of 1000 N/kg and a 150 m/s water jet delivered.

A rapid immunization strategy with a live-attenuated tetravalent dengue vaccine elicits protective neutralizing antibody responses in non-human primates.

Dengue viruses (DENVs) cause approximately 390 million cases of DENV infections annually and over 3 billion people worldwide are at risk of infection. No dengue vaccine is currently available nor is there an antiviral therapy for DENV infections. We have developed a tetravalent live-attenuated DENV vaccine tetravalent dengue vaccine (TDV) that consists of a molecularly characterized attenuated DENV-2 strain (TDV-2) and three chimeric viruses containing the pre-membrane and envelope genes of DENV-1, -3, and -4 expressed in the context of the TDV-2 genome. To impact dengue vaccine delivery in endemic areas and immunize travelers, a simple and rapid immunization strategy (RIS) is preferred. We investigated RIS consisting of two full vaccine doses being administered subcutaneously or intradermally on the initial vaccination visit (day 0) at two different anatomical locations with a needle-free disposable syringe jet injection delivery devices (PharmaJet) in non-human primates. This vaccination strategy resulted in efficient priming and induction of neutralizing antibody responses to all four DENV serotypes comparable to those elicited by the traditional prime and boost (2 months later) vaccination schedule. In addition, the vaccine induced CD4+ and CD8+ T cells producing IFN-γ, IL-2, and TNF-α, and targeting the DENV-2 NS1, NS3, and NS5 proteins. Moreover, vaccine-specific T cells were cross-reactive with the non-structural NS3 and NS5 proteins of DENV-4. When animals were challenged with DENV-2 they were protected with no detectable viremia, and exhibited sterilizing immunity (no increase of neutralizing titers post-challenge). RIS could decrease vaccination visits and provide quick immune response to all four DENV serotypes. This strategy could increase vaccination compliance and would be especially advantageous for travelers into endemic areas.

Needle-free jet injection for administration of influenza vaccine: a randomised non-inferiority trial

Administration of vaccines by needle-free technology such as jet injection might offer an alternative to needles and syringes that avoids the issue of needle phobia and the risk of needle-stick injury. We aimed to assess the immunogenicity and safety of trivalent influenza vaccine given by needle-free jet injector compared with needle and syringe. For this randomised, comparator-controlled trial, we randomly assigned (1:1) healthy adults (aged 18-64 years) who attended one of four employee health clinics in the University of Colorado health system, with stratification by site, to receive one dose of the trivalent inactivated influenza vaccine Afluria given either intramuscularly with a needle-free jet injector (Stratis; PharmaJet, Golden, CO, USA) or with needle and syringe. Randomisation was done with a computer-generated randomisation schedule with a block size of 100. Because of the nature of the study, masking of participants was not possible. Immunogenicity was assessed by measurement of the hemagglutination inhibition antibody titres in serum for the three viral strains included in the vaccine. We included six coprimary endpoints: three strain-specific geometric mean titre ratios and the absolute differences in three strain-specific seroconversion rates. The immune response of the jet injector group was regarded as non-inferior to that of the needle and syringe group if both the upper bound of each of the three 95% CIs for the strain-specific geometric mean titre ratios was 1.5 or less, and the upper bound of the three 95% CIs for the strain-specific seroconversion rate differences was less than 10 percentage points. We used t test for group comparison. This study is registered with ClinicalTrials.gov, number NCT01688921. During the 2012-13 influenza season of the northern hemisphere, we allocated 1250 participants to receive vaccination by needle-free jet injector (n=627) or needle and syringe (n=623). In the intention-to-treat immunogenicity population, all participants with two serum samples were included (575 in the jet injector group and 574 in the needle and syringe group). The immune response to Afluria when given by needle-free jet injector met the criteria for non-inferiority for all six coprimary endpoints. The jet injector group met the geometric mean titre criterion for non-inferiority for the A/H1N1, A/H3N2, and B strains (upper bound of the 95% CI for the geometric mean titre ratios were 1·10 for A/H1N1, 1·17 for A/H3N2, and 1·04 for B strains). The jet injector group met the seroconversion rate criterion for non-inferiority for the A/H1N1, A/H3N2, and B strains (upper bound of the 95% CI of the seroconversion rate differences were 6·0% for A/H1N1, 7·0% for A/H3N2, and 5·7% for B strains). We recorded serious adverse events in three participants, none of which were study related. The immune response to influenza vaccine given with the jet injector device was non-inferior to the immune response to influenza vaccine given with needle and syringe. The device had a clinically acceptable safety profile, but was associated with a higher frequency of local injection site reactions than was the use of needle and syringe. The Stratis needle-free jet injector device could be used as an alternative method of administration of Afluria trivalent influenza vaccine. Biomedical Advanced Research and Development Authority (BARDA), PATH, bioCSL, and PharmaJet.

Treatment of palmar hyperhidrosis with needle-free injection of botulinum toxin A

We read with great interest the article ‘‘Treatment of palmar hyperhidrosis with botulinum toxin type A: results of a pilot study based on a novel injective approach’’ [1]. We praise the authors’ new injective approach using a needle adapter to reduce pain and hand grip weakening. The needle adapter prevents Botulinum Toxin type A (BoNT/ A) from reaching deeper layers, producing less muscle weakening. The authors briefly discussed the treatment of palmar hyperhidrosis with needle-free (jet) injector, the MED-JET , requiring the anesthetic use. There are advantages to using needle-free anesthesia, prior to BoNT/A needle injection, as opposed to direct needle-free injection of BoNT/A: (a) Needle-free injection can waste up to 5 % of BoNT/A through splash and splatter (b) Delivery through a pressurized injector causes agitation, decreasing its efficacy. Newer models of jet injectors used with appropriate parameters reduce this waste [3]. Shome et al. [5] recently reported that agitation does not affect the efficacy of BoNT/A. Direct jet injection of BoNT/A is indicated for palmar hyperhidrosis in the needle-phobic patient. The rapidity and lack of needle use decrease apprehension. A vial of 100 units of BoNT/A is reconstituted in 5 ml of preserved saline. The driving pressure of the MED-JET is set to 140 pounds per square inch (psi) and the volume is set to 0.1 ml per spurt, delivering two units per spurt. The pressure is gradually increased with 10 psi increments until a subepidermal wheal is formed. Most procedures are accomplished with a driving pressure of 140 psi. Traditional jet injectors like the Dermojet are springloaded and have a fixed driving pressure of more than 1,400 psi. According to Mitragorti, these devices cause more pain, due to their deeper penetration level [2]. Naumann et al. [4] have used the Dermojet safely to inject BoNT/A directly into the skin for plantar hyperhidrosis, but do not advocate its use for palmar hyperhidrosis due to the potential damage to superficial nerves and vessels. The MED-JET, powered by carbon dioxide, has pressure settings ten times lower than that of traditional jet injectors. Higher driving pressures, higher volumes per spurt, wider nozzle diameters and shorter distances between the tip of the nozzle and the skin surface correlate with higher pain sensitivity and nerve or vessel damage. Further research is needed to objectively identify measurable parameters to insure safe and effective outcome in BoNT/A jet injection.

Intradermal fractional booster dose of inactivated poliomyelitis vaccine with a jet injector in healthy adults

For global eradication of poliomyelitis, inactivated poliovirus vaccine (IPV) needs to become available in all countries. Using fractional-doses (reduced-doses) may impact affordability and optimize the utilization of the production capacity. Intradermal administration has the potential to lower the dose without reducing immunogenicity. A needle-free jet injector may be a reliable way to administer vaccines intradermally. The primary objective of this randomized controlled trial was to compare the immunogenicity and tolerability of fractional-dose intradermal IPV (Netherlands Vaccine Institute, NVI) booster vaccination administered with a jet injector (PharmaJet) to full-dose and fractional-dose intramuscular vaccination with a needle and syringe. Immunogenicity was assessed by comparing the differences in the post-vaccination log2 geometric mean concentrations of neutralizing antibodies (GMC) between the study groups. A total of 125 Dutch adult volunteers with a well-documented vaccination history were randomized to one of four groups: full-dose intramuscular needle (IM-NS-0.5), full-dose intramuscular jet injector (IM-JI-0.5), 1/5th dose intramuscular needle (IM-NS-0.1), 1/5th dose intradermal jet injector (ID-JI-0.1). Vaccination with the JI was less painful (87% no pain) than vaccination with a NS (60% no pain), but caused more transient erythema (JI 85%, NS 24%) and swelling (JI 50%, NS 5%). Intradermal vaccination caused less vaccination site soreness (ID 16%, IM 52%). At baseline all subjects had seroprotective antibody concentrations. After 28 days, GMC were slightly lower in the ID-JI-0.1 group than in the reference group (IM-NS-0.5). The differences were not statistically significant, but the stringent non-inferiority criterion (i.e. a difference of 1 serum dilution in the microneutralization assay) was not met. After one year, differences in GMC were no longer apparent. In contrast, intramuscular vaccination with a fractional dose administered with a needle (IM-NS-0.1) was statistically inferior to full-dose intramuscular vaccination. This shows that intradermal but not intramuscular delivery of fractional-dose IPV may be sufficient for routine polio vaccination.

A pilot randomized study to assess immunogenicity, reactogenicity, safety and tolerability of two human papillomavirus vaccines administered intramuscularly and intradermally to females aged 18–26 years

Intradermal administration of human papillomavirus (HPV) vaccines could be dose-sparing and cost-saving. This pilot randomized study assessed Cervarix® and Gardasil® administered either intramuscularly or intradermally, in different doses (full-dose or reduced to 20%) by different methods (needle and syringe or PharmaJet needle-free jet injection device). Following an initial reactogenicity study of 10 male subjects, sexually naïve women aged 18–26 years were randomized to the eight study groups to receive vaccine at 0, 2 and 6 months. 42 female subjects were enrolled and complete data were available for 40 subjects. Intradermal administration of either vaccine raised no safety concerns but was more reactogenic than intramuscular administration, although still tolerable. All subjects demonstrated a seroconversion (titre≥1:320) by Day 95. Further evaluation of intradermal HPV vaccination and its potential for cost reduction in resource poor settings is warranted.

Real-Time, 2D and 3D Ultrasound Evaluation of Needle-Free Vaccination Devices

Brief Description of the Purpose of the StudyIntradermal injections induces better immunological response than subcutaneous or intramuscular injections with smaller vaccine volumes. Real-time, 2D and 3D Ultrasound imaging was performed to better understand tissue distribution of needle-free-jet-injection (NFJI) systems to evaluate depth of penetration and tissue dispersion of vaccines.MethodsTwo different brands of NFJE were evaluated comparing intradermal injection performances. Twenty healthy human volunteers were selected to participate in the study. They were equally distributed among two device groups according to racial, age, sex and BMI. Two needle free injections of 0,2 and 0,5 ml saline solution were monitored using real time ultrasound imaging scanning tissue distribution, cavitation and leak back phenomena. Imediately, 2D and 3D scans were performed to evaluate dermal thickness pre and post injection, maximum dispersion and maximum depth of injection. These data were analised with ANOVA and Mann-Whitney /Wilcoxon tests.Main ResultsThe skin thickness not varies significantly with populational parameters but there were significant differences between pre and post injection thickness. Ultrasound could confidently discriminate intradermal and/or subcutaneous saline distribution in patients with different populational parameters and different injector brands, pressure profiles and performances.Importance of the ConclusionsUltrasound is a good, harmless, confident, reproductible and cheap method to evaluate performance NFJI devices optimization with huge impact in populational immunization. Brief Description of the Purpose of the StudyIntradermal injections induces better immunological response than subcutaneous or intramuscular injections with smaller vaccine volumes. Real-time, 2D and 3D Ultrasound imaging was performed to better understand tissue distribution of needle-free-jet-injection (NFJI) systems to evaluate depth of penetration and tissue dispersion of vaccines. Intradermal injections induces better immunological response than subcutaneous or intramuscular injections with smaller vaccine volumes. Real-time, 2D and 3D Ultrasound imaging was performed to better understand tissue distribution of needle-free-jet-injection (NFJI) systems to evaluate depth of penetration and tissue dispersion of vaccines. MethodsTwo different brands of NFJE were evaluated comparing intradermal injection performances. Twenty healthy human volunteers were selected to participate in the study. They were equally distributed among two device groups according to racial, age, sex and BMI. Two needle free injections of 0,2 and 0,5 ml saline solution were monitored using real time ultrasound imaging scanning tissue distribution, cavitation and leak back phenomena. Imediately, 2D and 3D scans were performed to evaluate dermal thickness pre and post injection, maximum dispersion and maximum depth of injection. These data were analised with ANOVA and Mann-Whitney /Wilcoxon tests. Two different brands of NFJE were evaluated comparing intradermal injection performances. Twenty healthy human volunteers were selected to participate in the study. They were equally distributed among two device groups according to racial, age, sex and BMI. Two needle free injections of 0,2 and 0,5 ml saline solution were monitored using real time ultrasound imaging scanning tissue distribution, cavitation and leak back phenomena. Imediately, 2D and 3D scans were performed to evaluate dermal thickness pre and post injection, maximum dispersion and maximum depth of injection. These data were analised with ANOVA and Mann-Whitney /Wilcoxon tests. Main ResultsThe skin thickness not varies significantly with populational parameters but there were significant differences between pre and post injection thickness. Ultrasound could confidently discriminate intradermal and/or subcutaneous saline distribution in patients with different populational parameters and different injector brands, pressure profiles and performances. The skin thickness not varies significantly with populational parameters but there were significant differences between pre and post injection thickness. Ultrasound could confidently discriminate intradermal and/or subcutaneous saline distribution in patients with different populational parameters and different injector brands, pressure profiles and performances. Importance of the ConclusionsUltrasound is a good, harmless, confident, reproductible and cheap method to evaluate performance NFJI devices optimization with huge impact in populational immunization. Ultrasound is a good, harmless, confident, reproductible and cheap method to evaluate performance NFJI devices optimization with huge impact in populational immunization.

PS17 - 81. Pharmacology of rapid-acting insulin injected by needle-free jet-injection in patients with diabetes

Insulin injected by a jet injector dispenses over a larger subcutaneous area than insulin administered by a syringe, which may facilitate more rapid absorption.