Needle-free drug delivery systems

Lidocaine is absorbed rapidly after parenteral administration and from the gastrointestinal and respiratory tracts. Although it is effective when used without any vasoconstrictor, epinephrine decreases the rate of absorption, such that the toxicity is decreased and the duration of action usually is prolonged. In addition to preparations for injection, an iontophoretic, needle-free drug-delivery system for a solution of lidocaine and epinephrine (lontocaine) is available. This system generally is nsed for dermal procedures and provides anesthesia to a depth of np to 10 mm. 

Needle-Free Drug Delivery Systems. The three types of needle-free drug delivery systems are liquid, powder, and depot injections. Each of these types uses some form of mechanical compression to create enough pressure to force the medication into the skin. Although these needle-free delivery systems cost more initially and require more technical expertise... 

A drug product can only be successful if it is delivered in a timely manner to the site of action in a way that will be amenable to the patient and in a way to ensure product quality. Different routes of administration may be used to achieve either systemic or local delivery of the protein. Devices such as needle-free injectors and nebulizers may be used to deliver the protein and to enhance patient compliance with use of the drug. Both the route of administration and the decision to use a device are optimally determined early in clinical development of the protein so that there is plenty of clinical experience with the final product. Some... 

The present summary will cover only those technologies where the drug formulation itself is used to penetrate the skin via its mechanical energy. It will not describe any technology where a needle is used to puncture the skin, even if the needle is not visible to the patient or only the epidermis is punctured, such as mini-needles, microneedles, pen injectors, or autoinjectors. Also excluded are systems that ablate the skin mechanically or otherwise disrupt its chemical or mechanical structure to increase its permeability, such as laser ablation, microdermal ablation, electroporation, or iontophoresis. These are usually referred to as transdermal drug delivery, but can also be described as needle free. 

There are instances of older designs of needle-free injectors that, even with a well-characterized molecule such as insulin, show substantial differences between needle-free and needle delivery. However, improvements in the understanding of the aforementioned principles as well as advancements in the design of needle-free injectors have led to the recent reporting of improved clinical data. Table 1 summarizes an incomplete list of drugs for which there exist clinical data from needle-free administration, all of which demonstrated broadly similar performance between the needle-free system and the needle system (not every report provides sufficient data to determine if bioequivalence was demonstrated). 

More investigation is needed into transcutaneous delivery. Needle-free systems such as jet injectors , which force liquid or powdered drug though the skin by the means of compressed gas, could be an alternative if discomfort (bruising) is minimised. The microneedle system of delivery also seems very promising. Compared with hypodermic needles, microneedles do not significantly stimulate nerve endings and are thus well tolerated. 

The hi-dose delivery system for our intransal ketamine product candidate provides non-invasive (i.e. needle-free) administration compared to IV or IM injections, via a rugged, simple to use device that can be patient-administered if necessary. Each disposable device delivers a total of 30 mg ketamine with well-characterized, predictable pharmacokinetics. This approach to delivering subanesthetic doses of ketamine may be particularly advantageous in emergency situations where convenience, speed of drug delivery/onset, and avoidance of accidental needle sticks in healthcare providers are desirable. In addition, our intranasal ketamine product candidate was formulated to minimize neurotoxicity, a question that has been raised regarding the differently formulated ketamine product currently approved for anesthesia. 

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