Interest in the convenience and safety of pre-filled syringes is growing to the extent that some commentators are suggesting they will largely replace the traditional syringe for standard medical care.
The technology has been around for decades and is slowly gaining popularity with the medical profession as a safe, convenient and cost-effective solution. More than 50 drugs and vaccines are available in this way with more companies providing the product and more countries and health services adopting this option all the time. Anaesthetics, vaccines, insulin, biologicals for treatment of inflammatory varieties of arthritis and psoriasis are just some of the applications of this technology. Pre-filled syringes virtually eliminate waste, minimise the opportunities for mistakes and decrease potential for contamination, in addition to which they are much easier for patients to manage in a home environment. Issues around their use involve shelf life and the safety of the plastic packaging against proven glass receptacles but studies have shown they are certainly capable of meeting the required standard.
Elimination of waste is a major argument in their favour because standard glass phials are routinely overfilled by as much as 25% to ensure there is enough drug in the phial to allow for ease of filling an ordinary syringe – right down to the last dose. This can be very expensive, particularly with compounds which are difficult to produce. By pre-filling the syringe over-filling is virtually eliminated. Repeated use of the same phial to draw doses also involves a risk of contamination, which is eliminated by using a pre-filled syringe. Increased safety and speed of access are arguments in the favour of ready-prepared dosage in an emergency context and for patients administering their own doses at home, when they are more comfortable not having to draw up their own medicines.
In February 2015 a Smithers Rapra market report into pre-filled syringes predicted continued growth in this market to $6.6 billion by 2020, accounting for 6.7 billion units. New developments include the two-chamber syringe for mixing dried compounds with water prior to injection. The mixing used to have to carried out by hand but it can now be done with pre-measured quantities in a sealed environment – further reducing opportunities for error and contamination. Announcing their joint development with Arte Corporation, ProJect Pharmaceutics described the manufacturing process of the two-chamber product: “The diluent is filled first and can be autoclaved as required by international guidelines. The drug solution is filled into the second chamber and completely sealed on the filling line before entering the freeze drier. Due to its special design, the system opens by itself within the freeze drier enabling lyophilization of the drug solution in presence of the diluent.”