Popular as this technology is, there are others vying for a niche in the same markets with equal claims on convenience and popularity with patients and clinicians alike.

In 2011/12 Garcia-Diaz et al studied patient satisfaction and fear levels for both pre-filled syringes and a pen. The 30 long-term arthritis patients at Hospital Moises Broggi in Barcelona had been using the syringe before being switched to the pen after suitable training. Results showed no significant difference with management of the device or with post-injection pain; satisfaction levels of 90% for the syringe and 93.3% for the pen were recorded but patents showed statistically significant increased levels of fear with the syringe. In diabetes patients, pen use is very common and many patients re-use the needles on their pens, although these needles are designed to be used ideally only once. Mismikova et al studied three groups using insulin pens in Moscow in 2011 and found that patients using a single needle for seven days had more pain, increased bacterial contamination than those using a needle for four those only using the needle once had the lowest levels. Hyperemic foci at injection sites were found only in the groups using needles multiple times.

Used correctly, pens are very popular and suppliers are constantly working to improve their designs based on feedback from patients and practitioners, whose concerns were particularly needle-stick injuries. For example in April 2015 Oxfordshire company Owen Mumford announced their latest product called Autoject Micro. Business development manager George I’ons said: “Autoject Micro has been developed to make it easier for patients and healthcare professionals to deliver single dose injectable treatments while also addressing cold store and logistics costs with its smaller form factor. Its intuitive design and safety features have been created to address key patient concerns such as needle-stick anxiety and adherence, while providing advanced drug delivery capabilities.”

Earlier in the same year the same company’s Unifine Pentips Plus pen needle won a Red Dot Award. At that time Richard Walker, global product manager for the company, said: “The initial concept behind Unifine Pentips Plus was to make the injection process as easy and comfortable for the end user as possible, which plays an integral part in encouraging good self-management practices. “The research and design team went back to the drawing board to create a completely new solution for the long-established standard insulin pen. [The product] is proven to encourage better needle change behaviour and for our design to be recognised by the judging panel at Red Dot is great news.” In situations where many injections need to be carried out or where patients are very fearful of needles, science fiction has become reality to offer the hypospray. Although not universally accepted as the terminology for needle-free injection devices, the Star Trek word does seem to have entered the lexicon. Using compressed air or a spring system to inject a thin stream of fluid either subcutaneously or intramuscularly in 0.1second or less, there is no needle and therefore no risks associated with needle re-use or needle-stick injuries.

In September 2015 Pharmajet, one of the manufacturers of such devices, announced that its equipment would be used across the USA for seasonal flu vaccinations through a pharmaceutical supply company. CEO Ron Lowy said: “Entering the market, the Pharmajet needle-free injector has been well received by patients and health care providers alike. Based on our post-market surveys with patients receiving a needle-free flu shot, 93 per cent of patients and 87 per cent of health care providers reported that they would choose the Pharmajet needle-free option again for the up-coming flu season.” The previous year the company announced that it was the only needle-free injection company to receive a performance, quality and safety pre-qualification certificate from the World Health Organisation (WHO), allowing its Stratis jet injectors to be used for mass immunisation campaigns.

Diabetes patients are another major potential user group for this technology, especially those individuals with a needle phobia. In early 2016 Glide Technologies announced progress with its solid dose needle-free system and exenatide, a GLP-1 antagonist for the treatment of type 2 diabetes, showing no statistical difference between the solid product and Byetta, the current liquid product. Glide technology uses a spring-loaded mechanical device to introduce tiny solid pellet of a drug or vaccine which quickly dissipates into the body.

The company announced: “The technology has multiple advantages over currently marketed liquid peptide products, which are needle administered and require cold chain logistics and refrigeration in the home. In particular, the technology has the potential to significantly improve patient compliance, which is important where self-administered injections are required, such as in diabetes. The results follow previously announced successful proof-of-concept studies with Glide’s novel solid dose formulations of currently marketed liquid products teriparatide and octreotide. Consequently Glide’s solid dose formulation technology has now achieved equivalence across a series of peptide products, demonstrating the flexibility of the platform to deliver this important class of therapeutics.”

The variety of injection technologies and range of manufacturers available is testament to the importance place on having the right tool for the job by millions of patients and medical practitioners. Market forces are driving innovation at a staggering rate, although different solutions are being adopted in different places at different rates and some prove unsuccessful in the long term. There is certainly no shortage of imagination or ingenuity being brought to bear on this fast-moving field.