How we got to now: Aseptic filling for pharmaceutical cartridges

The PBS documentary How We Got To Now highlights the unintended, evolutionary consequences of inventions. In this article, we chart the path to the development of the auto-injector for biologics, and therefore, the need for new aseptic filling methods for pharmaceutical cartridges.

The history of auto-injectors

The journey to auto-injectors starts at the Gutenberg printing press. Printing creates a need for eyeglasses, which spurs the development of optics. The German and Italian glass industries grow (hint: they’re still going strong). Optics result in the microscope, and the expansion of chemistry and microbiology. Medicines are invented, which are packaged in glass vials and ampoules, then administered using syringes.

The need for auto-injectors and filling cartridges begins during World War II as battlefield medics at the front lines don’t have the time to perform sterile injections. In 1943, Wyeth introduced the Tubex syringe cartridge, which used a metal injection device containing a disposable glass cartridge. This made injection easier and made its way into a variety of markets like dentistry and diabetes care. Today, self-administration by cartridges is an important drug delivery method.

The Tubex syringe cartridge was the first auto-injector, used in battlefield medicine during World War II
The Tubex syringe was the first auto-injector, used in battlefield medicine during World War II.

Getting to now: Flexible, high-value cartridge filling

Since the cartridge was created, pharmaceutical companies have been able to fill them in high volume. Think of a product like dental anesthetics. These are drug products with certain demand and long product lifecycles. Time can be taken for customization and refinement of the manufacturing process, including the implementation of high-speed, conventional filling lines. It is expensive and complex to achieve precision in this type of filling.

Now, try to apply that same model to the delivery of biologics, where each unit is high-value, and there could be significantly more demand volatility. Product lifecycles are shorter and more uncertain. Investing in that level of infrastructure and precision for cartridge filling does not make as much sense. The old model breaks down.

That situation leaves customers looking for an easier, more flexible path to building cartridge filling capacity. Filling accuracy and stopper placement are key goals; think extremely accurate and bubble-free.

The Vanrx SA25 Aseptic Filling Workcell can fill cartridges and syringes for auto-injectors, such as the West SmartDose.
The Vanrx SA25 Aseptic Filling Workcell can fill cartridges and syringes for auto-injectors, such as the West SmartDose.

So how do we collectively achieve this level of process precision for low-volume, high-value medicines in cartridges?

The How We Got To Now story is that we choose an entirely robotic filling and closing process for its repeatability and precision. Robots are better suited to handling pre-sterilized, nested cartridges. The interface between robotics, cartridges, and stoppers requires advanced control systems.

The Vanrx SA25 Aseptic Filling Workcell takes advantage of:

  • Nested ready-to-fill cartridges that eliminate the need for in-house washing, depyrogenation and sterilization.
  • The precision and repeatability of robots that perform all the aseptic processes.
  • A completely digital architecture and control system that enables repeatable, recipe-driven process development and manufacturing.
  • A unique closing process that advances stoppering technology to achieve new levels of precision.

Vanrx customers find themselves in the position to be able to fill nested cartridges at a level of precision 10 times better than competing technologies. While others are saying that nested cartridges cannot be filled to the specifications of larger traditional lines, our customers are finding that our systems can do just that to a quality level of better than Six Sigma.

That is how we got to now