The untapped potential of drug capsules

The untapped potential of drug capsules

What groundbreaking innovations lie ahead for capsules and how will these developments redefine their role in drug delivery? 
Shincy Jacob, Subhashis Chakraborty.

Today’s health care market is overflowing with myriad products, making it increasingly difficult for businesses to stand out. This is particularly true for oral dosage forms, which currently account for over 80% of the market. This creates a daunting challenge for drug developers who must continually innovate in order to differentiate products. 

Unlike prescription drugs, the visibility of over-the-counter (OTC) medicines on the shelf play a significant role in consumer decision-making. In a saturated market where consumers are constantly bombarded with choices, product differentiation allows a brand to distinguish itself and gain competitive advantage by highlighting its unique features, benefits or qualities. It can also contribute to building brand loyalty, attracting a specific target audience, and done correctly it can enable a company to charge a premium for its distinctive offerings.

Achieving product differentiation in these sectors is not without challenges, however. Stringent regulatory requirements can limit the scope for innovation, necessitating companies to navigate complex approval processes. Moreover, the restrictions on advertising prescription drugs poses a significant hurdle for pharmaceutical companies. Overcoming these challenges requires a delicate balance between scientific credibility, regulatory compliance, and effective marketing strategies to establish a brand as a trusted and differentiated player in the market.

Capsules are a widely adopted oral dosage form for pharmaceutical use and are favored by formulators for their versatility.  Patients and consumers appreciate capsules for their convenience.  They offer a convenient and easily ingestible option for delivering a range of active ingredients, ensuring high dosage adherence. Nevertheless, researchers may have overlooked the potential of capsules as a product differentiator. 

Despite the continual advancements, the pharma industry has yet to witness a revolutionary breakthrough in the design or functionality of empty hard capsules. The question looms: What groundbreaking innovations lie ahead for capsules, and how will these developments redefine their role in drug delivery? 

Capsules for every purpose

Capsules offer a versatile range of ready-to-use options that extend beyond the more conventional immediate-release applications for powders. For example, the possibility of delayed-release and enteric capsules have proven invaluable for formulations like enzymes and probiotics, requiring protection from stomach acid and necessitating targeted delivery in the intestines. Delayed release ensures that active ingredients reach their intended site of action, enhancing the efficacy of the pharmaceutical or nutraceutical products in question.

The ability to encapsulate liquids, semi-solids, and pastes in a single unit also sets capsules apart from other dosage forms. This diverse application supports precise dosing, as compared to solutions and suspensions dispensed via bottles. Capsules also offer a unique solution for formulating poorly soluble drugs, enabling the use of lipids as a carrier to enhance their solubility and bioavailability. They offer a plethora of liquid-filled combinations, such as capsule-in-capsules, pellets-in-capsules and tablets-in-capsules which, when delivered in clear transparent capsules, also provide an aesthetic appeal to the final product. In addition, the smooth surface and easily ingestible nature of capsules contributes to a positive consumer experience, a crucial factor in today’s competitive landscape.

Moreover, the unique advantage of encapsulating various active ingredients — even if they are incompatible — within a single capsule presents new possibilities. This addresses specific patient compliance challenges, by offering a convenient means of administering multiple medications or supplements simultaneously, to help simplify treatment regimens.

Beyond conventional methods 

The simple idea of sprinkle capsules, utilizing standard capsules in the drug delivery system, stands as an excellent example of value-added product differentiation. This innovation, made possible through capsules, sets it apart from other oral dosage forms. It offers significant benefits, particularly to geriatric and pediatric patients with swallowing difficulties, where a capsule can be opened to disperse its contents over liquid or soft food for ingestion. And, in both cases, the convenience and adaptability of sprinkle capsules contribute to improved patient compliance.

Tabsules — featuring a caplet enclosed in two identical capsule shells — provide a multifaceted approach to product enhancement. Not only do they offer tamper-proofing, serving as a visible indicator of product integrity, but tabsules also offer a competitive advantage by providing an innovative approach to existing formulations without the need for a comprehensive reformulation. This innovation allows companies to refresh their product presentation without compromising the established formulation. Additionally, tabsules contribute to an improved customer experience by masking the potentially bitter taste of tablets and facilitating easier swallowing.

Clinicaps are capsules with unconventional dimensions customized to enable execution of double-blind clinical trials. These are engineered with relatively longer caps to ensure a tamper-evident design. They have broader width and available in different lengths which facilitates the concealment and blinding of large or uniquely shaped tablets or other forms of solid oral dosages. This unconventional design can be leveraged to serve as a visual differentiator, enhance aesthetic appeal and communicate a sense of innovation adding value and uniqueness in a saturated market. 

Naturally clean capsules

Today’s consumers are well-informed and are increasingly conscious of what they’re consuming. This has translated into a rising demand for all things natural and clean. 

In recent years, the shift from animal-sourced gelatine towards plant-based alternatives has marked a significant evolution in the realm of empty hard capsules. Among these alternatives, hydroxypropyl methylcellulose polymer (HPMC), has emerged as the front-runner, holding an undeniable dominance in the capsule market. HPMC caters to vegetarian and vegan consumers, while delivering performance characteristics comparable to gelatine. This remarkable balance of suitability and performance has cemented HPMC's position as the leading capsule polymer. 

In line with this growing demand for animal-free products, new-generation polymers like pullulan and starch are also gaining prominence in capsule manufacturing. These polymers, renowned for their exceptional film-forming properties and stability, are making waves as compelling alternatives. Their versatility allows them to encapsulate a diverse range of formulations, catering to the evolving needs of the pharmaceutical and nutraceutical industries.

With natural choices gaining prominence, the evolution of capsules extends beyond the choice of polymers to encompass the coloring agents used. Today's capsules can now be colored using natural colorants derived from fruits, vegetables or plant-based sources.

Transformative capsule customization

Today, almost endless capsule customization options exist — helping to make brands become instantly recognizable.

For example, the introduction of capsules with a pearl-like finish offers exciting possibilities for creating aesthetically appealing products, particularly for nutraceuticals or cosmetics. This innovative approach aligns with premium consumer expectations, adding elegance and luxury to capsules to help them stand out on shelves. 

Furthermore, the array of customizable printing options for capsules can enhance product distinctiveness and brand appeal. From intricate logos to specific color combinations, these techniques allow companies to align capsules with brand aesthetics.

360° printing — a technology that's difficult to replicate — safeguards capsules from counterfeiting. Printing dosage information, branding elements or unique patterns can enhance product recognition and foster a stronger connection between the product and its brand, aiding their visibility on market shelves — and recognition by consumers. Additionally, capsule printing aids polypharmacy patients, particularly the elderly, in correctly identifying medications in order to prevent potential mix-ups.

Capsules: a testament to formulation innovation

In essence, capsules not only serve as a vehicle for drug delivery, but also stand as a testament to innovation in pharmaceutical formulations. Their adaptability to diverse release profiles, compatibility with different types of formulations, and ability to simultaneously enhance both bioavailability and patient compliance make them a cornerstone in the pursuit of effective and patient-centric health care solutions. 

As the industry continues to evolve, capsules remain steadfast and adaptable vehicles for delivering health-promoting substances, contributing to the broader landscape of product differentiation. 

About the Author

Shincy Jacob | Product Manager, ACG Capsules

Subhashis Chakraborty | Head, Global Product Manager, ACG Capsules