Third-generation capsules: What lies ahead for drug delivery

The story of modern-day healthcare is often told through the lens of drug-development in medical sciences, and rightly so. However, the role of pharmacology and drug delivery systems cannot be overstated.

In the last four decades, capsules have emerged as a crucial device for advancing healthcare across continents. They offer obvious benefits over other forms of medication, including ease of self-administration, precise dosing and targeted delivery.

They are used to treat a range of conditions and can be produced at a lower cost than other dosage forms. They also have longer shelf life, are easier to store and transport to the last mile – other benefits include taste masking, as well as being aesthetically pleasing and tamper evident.

Capsules have been around for more than 100 years and, with an impeccable track record and with billions of units manufactured every year, they lead the fight to make medication more safe, accessible and affordable in high- and low-income countries alike. As the world's population grows and ages and diseases rise, the humble capsule also evolves.

A couple of Frenchmen are credited with patenting the capsule in 1834 – a small gelatine shell enclosed with a drug, released after ingestion. In their early days, what we called the first-generation, capsules were unstable, prone to cracking and leaking, unpackaged and thus unsanitary and thereby potentially dangerous for patients.

Absence of automated filling machines also created limitations on how many capsules can be filled manually and stuck together by workforces. I personally have had a front-row seat to the evolution of capsules.

Advances in technology led to the development of packaging that has added shelf life, making them more stable and reliable, and the advent of automated filling machines increased productivity, decreased human intervention making them more hygienic and reducing possibilities for human error.

Cut to 2000s, the second generation of capsules really pivoted and scaled from animal-based gelatine to plant-based cellulose. Though the technology existed previously, enhanced scale made these capsules more accessible to people with dietary restrictions and addressed ethical concerns on animal products.

Capsules are no longer limited to delivering drugs in powder form, as advances in materials and manufacturing have led to diversification in ingredients that can be encapsulated. They are a versatile drug delivery system that can be used to deliver various formulations, including granules, pellets, pastes and even liquids.

Not just for humans, capsules have evolved for making animals drug delivery easier. Flavouring to improve the intake of capsules is another catching trend, which is used for making medicines for pets and cattle.

Advances in materials and manufacturing processes have led to a diversification in the kind of ingredients that can be encapsulated. The shell of a capsule can be leveraged to design capsules for delayed-release and targeted-release of drugs in the body, enhancing the efficacy of the medication. Manufacturers can also make specific capsule shells that protect the ingredients inside against degradation, thus improving the shelf life of finished products.

Today we are at the precipice of revolutionizing this technology once again. Advances in combination liquid fill solutions and the probability of scaling world’s first two-in-one (any combination pellets with liquid, or pellets with powder or liquid with liquid, the combinations are versatile) capsule product with a movable membrane, is now a possibility.

Collectively these capsule technologies will usher in a new era in new combinations of dietary supplements, and even non-prescription or over-the counter remedies as well as prescription medicines to be delivered in a single dose. Research has shown that water and fat-based liquids are often necessary for the proper absorption of active ingredients in the digestive system.

By providing these components in the liquid portion of the capsule products, the bioavailability – the ability of a drug or other substance to be absorbed and used by the body – of the key ingredients can be considerably improved. The more bioavailable a product is, the greater its beneficial effect on the body. As a result, lower dosages may be required, side effects are potentially reduced, and the efficiency of delivery is substantially boosted.

This revolutionary breakthrough also allows previously nonviable combinations to be delivered simultaneously. Various liquids, including oils, can be contained within a product together with other active ingredients. This allows for a single capsule to deliver multiple ingredients, resulting in an unprecedented level of convenience and an innovative product delivery. This technological breakthrough is a solution to current formulation challenges with many combination therapies, including incompatible ingredients or molecules.

In the end, we are left with one question – what can you buy today for $0.20, which is reliable, safe to consume and helps you get better? That you trust the health of your family with? Capsules are arguably the safest and most reliable way to deliver medicine and as the march of progress continues in the fields of science and medicine, they continue to offer opportunities for innovation and will remain relevant in the years and decades to come.