Intranasal epinephrine in dogs: Pharmacokinetic and heart rate effects

Fast Acting, Dry Powder, Needle-Free, Intranasal Epinephrine Spray: A Promising Future Treatment for Anaphylaxis

BACKGROUND

Epinephrine intramuscular (IM) autoinjector is a life-saving drug for the emergency treatment of immediate-type allergic reactions (type I). Nevertheless, it is sometimes applied incorrectly or underused because of short shelf life, high costs, fear of use, or inconvenience of carrying. FMXIN002, a nasal powder spray of epinephrine, was developed as a needle-free alternative.

OBJECTIVE

To compare epinephrine pharmacokinetics, pharmacodynamics, and safety after the administration of the FMXIN002 nasal spray versus autoinjector.

METHODS

An open-label trial was performed in 12 adults with seasonal allergic rhinitis without asthma. Epinephrine pharmacokinetics, pharmacodynamics, and safety were compared between FMXIN002 (1.6 mg and 3.2 mg) administered intranasally with/without a nasal allergen challenge and IM (0.3 mg) EpiPen.

RESULTS

FMXIN002 3.2 mg, administered after a nasal allergen challenge, displayed a shorter Tmax than EpiPen (median: 2.5 minutes vs 9.0 minutes, statistically nonsignificant [NS]) and a significantly shorter time when the measured analyte concentration is 100 pg/mL during the absorption phase pg/mL (median: 1.0 minutes vs 3.0 minutes for FMXIN002, P < .02). Moreover, FMXIN002 3.2 mg administered after the challenge test has resulted in a doubling of the maximal measured plasma analyte concentration over the sampling period (1110 vs 551 pg/mL, NS); area under the curve from 0 to 8 hours was 56% higher (672 vs 431 hours pg/mL, compared with EpiPen, NS). Pharmacodynamic response was comparable at all treatments. FMXIN002 was well tolerated, and treatment-emergent adverse events (AEs) were mild, local, and resolved spontaneously. No AEs were reported after the administration of EpiPen in our study. FMXIN002 was stable for 2 years at room temperature conditions. However, variability in the pharmacokinetics (expressed in coefficient of variation) is high. Having a prior nasal allergen challenge results in a substantial increase and speed of absorption.

CONCLUSIONS

Intranasal absorption of dry powder epinephrine is faster than EpiPen offering a clinical advantage in the short therapeutic window for the treatment of anaphylaxis. The FMXIN002 product offers a needle-free, pocket-size, safe, user-friendly, and stable alternative to epinephrine autoinjectors.

Finding potential inhibitors against RNA-dependent RNA polymerase (RdRp) of bovine ephemeral fever virus (BEFV): an in-silico study

The bovine ephemeral fever virus (BEFV) is an enzootic agent that affects millions of bovines and causes major economic losses. Though the virus is seasonally reported with a very high morbidity rate (80-100%) from African, Australian, and Asiatic continents, it remains a neglected pathogen in many of its endemic areas, with no proper therapeutic drugs or vaccines presently available for treatment. The RNA-dependent RNA polymerase (RdRp) catalyzes the viral RNA synthesis and is an appropriate candidate for antiviral drug developments. We utilized integrated computational tools to build the 3D model of BEFV-RdRp and then predicted its probable active binding sites. The virtual screening and optimization against these active sites, using several small-molecule inhibitors from a different category of Life Chemical database and FDA-approved drugs from the ZINC database, was performed. We found nine molecules that have docking scores varying between -6.84 to -10.43 kcal/mol. Furthermore, these complexes were analyzed for their conformational dynamics and thermodynamic stability using molecular dynamics simulations in conjunction with the molecular mechanics generalized Born surface area (MM-GBSA) scheme. The binding free energy calculations depict that the electrostatic interactions play a dominant role in the RdRp-inhibitor binding. The hot spot residues, such as Arg565, Asp631, Glu633, Asp740, and Glu707, were found to control the RdRp-inhibitor interaction. The ADMET analysis strongly suggests favorable pharmacokinetics of these compounds that may prove useful for treating the BEFV ailment. Overall, we anticipate that these findings would help explore and develop a wide range of anti-BEFV therapy.Communicated by Ramaswamy H. Sarma.

Pharmacokinetics of intravenous, oral transmucosal, and intranasal buprenorphine in healthy male dogs

Effective management of pain in animals is of critical importance but options are limited for treating acute pain in dogs on an outpatient basis. The objective of this study was to compare the plasma concentrations and pharmacokinetics of a concentrated solution of buprenorphine, 1.8 mg/ml (Simbadol™) administered intravenously, intranasally, and via the oral transmucosal (OTM) route in healthy male dogs. Five healthy castrated adult male Beagle‐cross dogs were included in this randomized blocked crossover study. The dogs received 0.03 mg/kg body weight buprenorphine intravenously, intranasally, or via the OTM route, with a minimum 72‐h washout period between treatments. Blood samples were collected at multiple intervals up to 24 h post administration and buprenorphine plasma concentrations were determined by liquid chromatography tandem mass spectrometry. Non‐compartmental pharmacokinetic analysis revealed that the area under the curve of intravenous, intranasal, and OTM routes were 28.0 (15.1–41.3) h × ng/ml, 16.1 (3.4–28.7) h × ng/ml and 10.8 (8.8–11.8) h × ng/ml, respectively. The bioavailability of intranasal and OTM routes were 57.5 (22.7–93.7)% and 41.1 (25.5–69.4)%, respectively. Intranasal and OTM routes of administration of concentrated buprenorphine in dogs may allow for the provision of analgesic care at home.

Emerging Therapies in Anaphylaxis: Alternatives to Intramuscular Administration of Epinephrine

PURPOSE OF REVIEW

Anaphylaxis is a severe, life-threatening, systemic allergic reaction that should be recognized and treated promptly. Intramuscular (IM) epinephrine is the first-line treatment for anaphylaxis and there are no absolute contraindications to its use. Despite its established track record of efficacy and safety, physicians and patients face barriers in the recognition and treatment of anaphylaxis, including the maintenance and appropriate use of epinephrine auto-injectors. This has led to investigation into potential alternatives to IM epinephrine administration in anaphylaxis.

RECENT FINDINGS

This review investigates the current standard of care in the treatment of anaphylaxis, barriers to IM epinephrine use, and alternative therapies under investigation for administration in anaphylaxis. Alternative routes under investigation include intranasal, sublingual, inhaled, and needle-free intramuscular administration of epinephrine. There are currently numerous investigational alternatives to IM epinephrine therapy which could hold promise as future effective treatments in the emergent management of anaphylaxis.

Effects of Intranasal Epinephrine on Cerebrospinal Fluid Epinephrine Pharmacokinetics, Nasal Mucosa, Plasma Epinephrine Pharmacokinetics, and Cardiovascular Changes

PURPOSE

We aimed to assess intranasal (IN) epinephrine effects on cerebrospinal fluid (CSF) absorption, nasal mucosa quality, plasma epinephrine pharmacokinetics (PK), and cardiovascular changes in dogs.

METHODS

CSF epinephrine concentration was measured and nasal mucosa quality was evaluated after IN epinephrine 4 mg and one or two 4 mg doses (21 min apart), respectively. Maximum plasma concentration [C_max], time to C_max [T_max], area under the curve from 0 to 120 min [AUC_0-120], and cardiovascular effects were evaluated after epinephrine IN (4 and 5 mg) and intramuscular (IM; 0.3 mg). Clinical observations were assessed.

RESULTS

After epinephrine IN, there were no changes in CSF epinephrine or nasal mucosa. C_max, T_max, and AUC_1-120 were similar following epinephrine IN and IM. Epinephrine IN versus IM increased plasma epinephrine at 1 min (mean ± SEM, 1.15 ± 0.48 for 4 mg IN and 1.7 ± 0.72 for 5 mg IN versus 0.47 ± 0.11 ng/mL for 0.3 mg IM). Epinephrine IN and IM produced similar heart rate and ECG results. Clinical observations included salivation and vomiting.

CONCLUSIONS

Epinephrine IN did not alter CSF epinephrine or nasal tissue and had similar cardiovascular effects as epinephrine IM. Epinephrine IN rapidly increased plasma epinephrine concentration versus epinephrine IM.