How healthcare trends inform dosage forms

Capsules encompass one of the most popular solid oral dosage forms for pharmaceutical products, with the global empty capsule market predicted to rise to USD $3.7 billion by 2026. The growth in the capsule market can be partly attributed to the many options available for drugmakers regarding capsule material, sizes, colours, and printing options. With so many options available, formulators are spoilt for choice. However, selecting the correct capsule for specific product development can lead to challenges around drug complexity and stability.  

Pharmaceutical and Nutraceutical Global Trends Inform Dosage Forms 

Roberts began the webinar with how current pharmaceutical and nutraceutical trends have been informing oral dosage forms, with patient/customer centricity, R&D innovations, and additive and continuous manufacturing making some of the greatest impacts. Given these trends, some of the major focus areas for the industry include ease of manufacturing, modified release, global regulatory requirements, and specialised applications. Armed with a solid history of capsule evolution and what the pharma industry is looking for in capsule formulations, Roberts presented the advantages of capsules as a dosage form, citing easy encapsulation, quicker development of a new product, and less additives than traditional tablets, among others. In comparison to other solid dosage forms, capsules also require less steps in the manufacturing process than tablets and can achieve a combination fill. Roberts emphasised the ease of development and scalability of capsules given their versatility in holding almost any pharmaceutical or nutraceutical active ingredient. Powders can be blended, and tastes and odours masked with additional ingredients, offering drugmakers a versatile drug formulation option and patients a product that best suits their individual needs. 

Reiterating how global consumer healthcare trends regarding patient-centricity and manufacturing innovations are informing the capsule market, Roberts highlights the forecasted growth of the capsule market to reach USD $3.7 billion by 2026, with a 7.2% CAGR during the forecast period from 2021 to 2026. Given all that hard capsules have to offer and their predicted demand, what then are the criteria for selecting the right capsule for your drug formulation?  

The Right Capsule for the Right Product 

Bhat gave a comprehensive overview of criteria to consider when selecting the appropriate capsule for a product: 

1. Shell barrier to gas and water: moisture sensitivity of the drug’s formulation to both environmental humidity and humidity inside the formulation itself will affect the type of capsule used for a particular formulation. The Oxygen Transmission Rate (OTR) and Water Vapour Transmission Rate (WVTR)  

2. Reactivity of material filled: excipients will inevitably be utilised along with the API or ANI to improve the mode of administration, solubility, or even the density of the active ingredient. However, capsules may present incompatibility issues when considering their use for a particular drug formulation. Capsule fillings are generally unfavourable for use with reactive aldehydes due to cross-linking. In a similar vein, drug formulations which use anionic and/or cationic polymeric excipients will determine the type of animal gelatine capsule used because of different reactivity between the materials. 

3. Material composition and other parameters: Bhat also focused on the physical composition of the capsule itself. For some capsules, the material composition may be hygroscopic while others could cause a Maillard reaction upon contact with primary amides. Physical reactions will generate their own set of challenges that determine the type of capsule used. 

Encapsulating pharmaceutical and nutraceutical capsule challenges 

Bhat also gave a quick overview of various challenges faced by the pharma industry in regard to capsule formulations. Physio-chemical interactions, cracking of capsules, discoloration, colour interaction, and shell-fill were all cited as specific challenges for capsule manufacturing. Bhat presented several case studies related to these challenges.  

For example, dosage forms for the antifungal drug Itraconazole were developed and marketed as gelatin capsules but faced difficulties regarding dissolution. Hydroxypropyl methylcellulose (HPMC) capsules were tested and demonstrated that drug release was higher in comparison to gelatin capsules, and pellets did not remain entrapped in the capsules during dissolution.  

Bhat emphasised how such challenges in meeting global healthcare trends with capsule technology could provide ample opportunity for innovation in capsule formulation and modifications, as well as manufacturing practices and procedures. 

The nutraceutical industry is not immune to such challenges either, as Roberts presented on challenges faced by the nutraceutical industry. In a similar vein to the pharma industry, common challenges for inserting nutraceutical ingredients into capsules include formulation compatibility, moisture sensitivity, product stability, and animal origin products, among others. Again, case studies were presented to demonstrate how capsule modifications could meet the specific requirements (such as opting for non-animal origin capsules) for nutraceutical products. With healthcare trends looking towards meeting customer choices and lifestyles, capsule development and manufacturing has steadily been moving toward vegetarian or vegan capsule options. Consumer taste and product appeal, Roberts stated, have also informed the continuous development of nutraceutical and supplement capsule technologies to accommodate for stomach sensitivities, olfactory responses, and other sensitivities.  

Capsule Questions: what’s left for capsule technology? 

Some of the big questions remaining for the Roberts and Bhat concerned regulations around innovative capsule technology for patient centricity. While Roberts stated there could be some challenges regarding colour additives, however many capsule criteria are already regulated and accepted worldwide. With the market growth for solid dosage forms and in particular capsules increasing at the rate that it is, Roberts and Bhat both emphasised how capsule development and manufacturing must account for consumer healthcare interest and trends. 

Watch the full webinar on-demand here.