When evaluating different dosage forms, it is clear that hard-shell capsules provide significant advantages over tablets and pressed pills: they are more simple to formulate and easier to produce. With support from the right partner in terms of quality, technical services and training, drug manufacturers can increase productivity and optimize the profitability of oral solid dosage formulations.
The use of hard capsules simplifies the development and manufacturing of solid oral dosage forms. Compared with other OSD manufacturing, the hard-shell capsule production process is relatively simple (filling of the capsule body, placement of the cap on the body and sealing/banding). Formulation is also easier, and raw material costs tend to be lower because fewer excipients are required. Preparation of product for filling into capsules is also generally less intensive compared to granulation.
Tablet presses apply more stress on the active ingredient, and tablet formulations must address the challenges of flow, compressibility (without sticking), friability and bioavailability through proper dissolution. The capabilities of the two-piece capsule and filling process naturally overcome most of these obstacles. Most tablets are also subjected to a coating process, which introduces additional opportunities for process failure. The simplified nature of capsule production facilitates process transfer and scale-up. The same formulation can be used on low output and high-speed capsule filling machines — this is not often the case when switching from low- to high-speed tablet presses.
Practical steps to avoiding defects
Empty capsules with pre-existing defects can negatively impact the capsule filling process. Capsules must be dimensionally correct with consistent wall thicknesses and also be impeccably round to ensure that the body and cap are joined properly. Defective capsules can get stuck in the filling machine and may also lead to defects in the filled capsules, such as splits, pinholes, cap tucks and body folds — all of which can result in under-filled capsules, increasing the amount of loss per batch.
When these defects occur, operators are challenged to identify the source. Large particle sizes in the formulation, worn tooling in the capsule filler, weak sidewalls in the capsules or poor setup of the machine must be considered when troubleshooting. Problem-solving requires stopping the machine to diagnose the issue, where downtime can be significant.
A quality capsule supplier will utilize automated inspection equipment to remove visibly identifiable nonconformities, an approach that reduces defect levels far beyond traditional acceptance quality limit (AQL) criteria. Testing of fill materials in advance to make sure that they have the appropriate properties is strongly advised. Documenting equipment settings is also important to ensure consistent operation from batch to batch, and reduces setup time and material.
During product setup, ensure machine and capsule performance first by running the empty capsules through each step of the process to verify that rectification, closing and ejecting all run smoothly before introducing the fill material.
Leveraging continuous improvement
Utilizing continuous improvement, such as holding Kaizen events, or short improvement projects, helps everyone work synergistically on common goals, providing an opportunity to discuss problems, identify root causes and propose solutions.
The secret to fully optimized manufacturing
The processing benefits for hard capsules can only be fully realized if high-quality capsules, finely tuned filling machines and effective processes are utilized by highly trained operators.
CapsCanada customers benefit from the extensive expertise of our technical service team, whose members each have 20+ years of experience working with a range of equipment and formulation types. Our Technical Services Team dramatically improves operations productivity — in one case, a client shared their experience where CapsCanada training helped reduce capsule inspections by nearly 75%, while increasing run rates and efficiencies. CapsCanada offers several levels of training, including monthly webinars, on-site classroom education and hands-on machine training.
The numerous benefits of hard-shell capsules are best realized through collaboration with a partner that has expertise in all aspects of formulation and production. Become a CapsCanada Partner by switching to our premium hard-shell capsules and take advantage of the extensive training and technical support we offer to our customers at no cost. Reduce expenses and optimize your capsule production with CapsCanada.