| Ian Thompson at Ypsomed AG discusses the trends of pre-filled syringes, including disposable mono-dose auto-injectors and pen-injectors
In previous articles in this series we have discussed the scale of convenience for pre-filled syringes/auto-injectors and market trends for self-injection devices. In this article we focus on disposable pens and auto-injectors for mono-dose formulations which are influenced by the primary drug container and by the user/patient population.
The market for self-injection devices – pens and auto-injectors – continues to show above-average growth due to the continued development of injectable drugs. The market for pen injectors (see ‘What is a pen-injector?’) continues to evolve and expand for frequent use cartridge-based injections such as insulin, GLP-1, hGH, FSH and PTH. In addition, the demand for new drugs with less frequent injections is growing rapidly, requiring devices for mono-dose formulations such as autoinjectors (see ‘What is an auto-injector?’) and manual pen-injectors. The relevant indication areas include: long-acting formulations of traditionally frequently-injected drugs; drugs for the treatment of auto-immune diseases, such as TNF-inhibitors; and emergency injections. The pre-filled syringe is the primary container of choice for liquid-stable drugs, while the dual-chamber cartridge is most convenient for lyophilised formulations.
MONO-DOSE FORMULATIONS: PRE-FILLED SYRINGES AND DUAL-CHAMBER CARTRIDGES
Mono-dose formulations (see Figure 1) are single doses in which the dose is fixed and fully injected or can be varied and therefore partially injected. In either case, only a single dose is given and the syringe or injection device is disposed of after the injection. Ideally the drug is liquid-stable and the full dose is injected from a pre-filled syringe; the need to inject a partial dose using a pre-filled syringe is not very common. If different doses are needed, providing different drug volumes/concentrations and thus different SKUs (stock-keeping units) is often preferred, for example Amgen’s Aranesp/EPO. If the drug is lyophilised, the preference is to use a dual-chamber cartridge and inject the full dose after reconstitution. Manufacturing various concentrations of freeze-dried drugs is costly; there are examples of devices on the market today where a partial dose is injected from a dualchamber cartridge, such as Schering-Plough’s Pegintron/α-IFN (see Figure 2). |
