This article is part of a special feature on injectables that was published in the February issue of PTE Digital, available
Needle-free injection technologies have been developed for injecting liquid formulations, as well as injecting drugs and vaccines
in a solid dosage form. To date, however, the uptake of these systems has been slow.
Several liquid jet injection technologies are available on the market including Ferring’s Zomajet 2 Vision, Merck Serono’s
Saizen Cool.Click and Teva’s Tev‑Tropin Tjet, which are all human growth hormone products. Zogenix’s Sumavel DosePro is also
available, which is a sumatriptan injection for treating migraines. These liquid jet injection products, however, are expensive
compared with most auto‑injectors and pen‑injectors, which also have the added advantage of being easily used by patients
at home. The key benefits of avoiding a needle and ease of use of a liquid jet injector do not outweigh the overall cost of
goods compared with other delivery technologies.
One of the first companies to develop a needle‑free technology for injecting powdered drugs into the skin was PowderJect Pharmaceuticals.
As well as avoiding the use of needles, the technology also enabled a drug to be used in solid dosage form, which enhances
the stability of the product while also offering the opportunity for controlled release. The powdered drug was fired at the
skin at high velocity in a jet of helium, which made the technology complicated and expensive. The technology was approved
by the FDA in August 2007 for Anesiva’s Zingo, a local anaesthetic agent (lidocaine), but was withdrawn after only a few months.
In November 2008, Anesiva cited “continued manufacturing challenges and the need to recall product in the field due to a potential
non-safety related shelf life issue from a lot of unreleased product” as the reason for behind the decision to cease manufacturing
Despite the obstacles, I believe that needle-free delivery systems will replace traditional needles, but only for certain
applications such as growth hormone where there are already several needle‑free products on the market. For many drugs, I
believe there will be a choice between one or more needle‑based injection systems, and one or more needle‑free systems as
more products become generic and competition increases — in these circumstances, it is only the delivery system that really
differentiates products. The human growth hormone market, for example, has several big players (Pfizer, Merck Serono, Genentech
and Novo Nordisk) that offer multiple delivery technologies for human growth hormone. There are also other players in the
market, including Eli Lilly, Teva and Ferring, with at least one human growth hormone product available.
Needles will probably still be used in the hospital environment and when used by trained healthcare professionals. When self‑injection
is required or in environments when needles cause a particular issue, such as in pediatric applications, for example, there
is a strong argument and need for needle‑free products. It is unlikely, however, that needles will ever be eliminated in any
product applications, but needle‑free technologies will take a larger market share as they become more established. To achieve
this, however, the technology will ideally offer product benefits to patients and healthcare professionals beyond ease of
use and elimination of needles to help offset an increased cost of goods.
Solid dose injector technology
Our Glide SDI (Solid Dose Injector) enables the injection of APIs in a solid dosage form without the need for a needle. The
drug is mixed with selected excipients and individual dosages are produced as tiny rods with a point at one end. A dosage
is then pre‑filled into a single‑use drug cassette.
In use, the drug cassette is placed into a spring powered, handheld actuator. Pushing the end of the cassette against the
skin target charges the spring in the actuator. At a preset spring force, the actuator automatically triggers, pushing the
dosage from the drug cassette into the skin. The small, low cost drug cassette, which contains no sharps, can be safely thrown
away and the actuator can be reused hundreds of times, resulting in low cost per administration.
Because the drug is administered in a solid dosage form, the Glide SDI offers enhanced stability and potentially avoids the
need for refrigeration, as well as providing the opportunity for controlled release formulations by using slower dissolving
excipients rather than fast dissolving sugars. In the clinic in volunteer studies, the Glide SDI has been overwhelmingly preferred
to an injection with a standard needle and syringe.
A wide range of proteins, peptides and small molecules can be delivered using the technology. Preclinical studies with a range
of antigens have also shown improved efficacy for vaccines in the Glide SDI when compared to a standard needle and syringe
injection (data held on file at Glide Pharmaceutical Technologies Ltd).
Is the future needle-less?
Patients' want safer and better methods of taking their medicine. Additionally, with increased competition, pharmaceutical
companies need new ways of differentiating their products and extending the patent life on proprietary drugs.
Many drugs and vaccines need to be administered parenterally, but there is limited scope for further new developments in the
area of autoinjectors and peninjectors. As such, there will always be demand for new technologies, such as needle-free injection
devices. Although they are currently viewed as being costly — which is one of the reasons the technology is not more widely
used — the price of liquid jet injectors will fall as use increases. They may also be able to offer other liquid formulation
benefits such as improved stability or controlled release. Although these benefits can also be offered by needlebased technologies,
needlefree devices will also offer the benefit of ease of use and no needle.
The biggest advances in needlefree injection technologies will probably relate to their ability to inject solid dosage forms.
The key challenge, however, will be the successful commercialisation of the first solid dose injection product to prove that
the key perceived risks of manufacturing scaleup and regulatory approval for a novel drug delivery platform can be achieved.
Dr Charles Potter is CTO at Glide Pharmaceutical Technologies Ltd.