OSD Manufacturing Process: From Formulation to Finish


Aspirin is one of the most popular and commonly used medicines. Historically, this drug had a humble discovery 3500 years ago from the bark of the willow tree, known for its traditional herbal remedy. Similarly, all medicinal drugs originated from natural sources like herbs, plants, roots, bacteria, fungi etc. As science advanced, chemicals were put to use for fetching out the active ingredients from natural sources to produce more potent medicines.

With further technological development and with the collaborative efforts of researchers, biologists, physicians and chemists, drug discovery took rapid strides forward, and more throughput screenings and clinical trials began playing a vital role in relieving human pains and suffering.

Today, every pharmaceutical manufacturing plant project has a well-proven drug delivery system undergoing a series of well-defined processes. Oral Solid Dosage, which takes the course of tablets, capsules, soft gels, effervescence, gummies, and pills, involves key steps from formulation and development to packaging until the drug becomes ready to be consumed as a final drug product.

Formulation and Development: 

The process begins with formulation followed by development, wherein the active pharmaceutical ingredient (API) is combined with suitable excipients to create a stable and effective dosage form. Formulation development is carried out with an effective approach to attain the desired drug release profiles, enhanced bioavailability, and significant regulatory compliance. In the case of highly potent API, specialised technology is employed to reach a good solubility level with ensured therapeutic efficacy. All in all, the excipients and API must be well understood to have a well-defined formulation.


Granulation is a continuous manufacturing process in which the powdered API and excipients are agglomerated into granules to improve the flowability, compressibility, and uniformity of the powder mixture. The core granulation methods for pharma manufacturing comprise wet granulation, dry granulation, and direct compression, which are selected depending on the operational conditions, formulation properties and requirements.

Dry granulation – This economical method is most suited when the temperature and moisture-sensitive compounds need to be critically controlled. The granulation technique involves slugging, i.e. compressing the small, dry particles into larger granules to form a tablet of the right ingredient ratio with the right amount of excipient. 

Wet Granulation – This one is regarded as a superior method for its ability to work without special excipients and for providing content uniformity. The procedure is adaptive and reproducible and calls for perfect dispersion and preparation of granules. The quick processing time makes dealing with soluble low-dose medication easier.

Direct Compression – Direct compression is a simplified and shorter process of ingredient mixing that works well with heat and moisture-sensitive APIs and allows for tablets to disintegrate into particles of API instead of granules, as in the case of wet granulation. This method also helps avoid extreme compaction pressure during tablet production.

Isolators/containment systems: 

Dealing with potent products necessitates incorporating containment systems. These pharmaceutical isolators are built-in air filtration systems and fulfil the demand for high personnel and product protection from external contaminants. Positive pressure isolators help maintain sterility by protecting the product against contaminants. In contrast, negative pressure isolators provide personnel and or environmental protection by containing hazardous or toxic materials inside the isolator. The choice of granulation isolator system is a process strategy based on batch size and capacities.


After granulation, the granules may undergo blending with additional excipients, such as diluents, disintegrants, and lubricants. Blending ensures a homogeneous distribution of API and excipients throughout the mixture, enhancing content uniformity and tablet-to-tablet consistency. The prime objective of the blending process is to ensure the adequacy of mixing the ingredients through various mixing equipment/blenders such as octagonal blenders, V blenders, bin blenders, conta blenders etc.


Compression is known to be one of the most challenging steps as it can have a direct bearing on the hardness of the tablet and, resultantly, on the dosage form integrity and bioavailability. It includes compressing the granules or blending them into tablets using a high-speed mechanical device – a tablet press. The compression process involves precise squeezing of ingredients to reach a required tablet shape, vizround, oval, or scoredThe compressed tablets must determine the physical and chemical properties of the tablet while ensuring appropriate hardness, thickness, and weight.


In the tablet coating process, a thin layer of coating material is applied to the tablet surface to achieve the desired properties of dosage form over the uncoated variety. Equipment such as auto coaters for granulation line bring effectiveness to the coating operation by serving multiple purposes, such as protecting the drug from environmental factors, improving swallowability and product stability, providing taste masking, or modifying drug release characteristics  The amount of coating on the surface of a tablet is critical to the effectiveness of the oral dosage form.


The packaging of medicines must be done with utmost care. Once the tablets are manufactured and coated, they go through critical packaging to avoid contact with external components like heat, air, and water, which may alter the drugs’ properties. This requires primary packaging, where the tablets are placed in blister packs, bottles, or other suitable containers. Secondary packaging, such as labelling and cartoning, is also performed to provide information and protect the product during distribution. The selection of the package begins with the determination of the product’s physical and chemical characteristics.

Quality Control: 

Throughout the manufacturing processes, quality control is crucial in ensuring product quality and compliance with regulatory standards. The quality control process in a pharmaceutical manufacturing plant project takes into consideration the raw materials, in-process samples, and finished products for various parameters, including identity, purity, potency, dissolution, and physical attributes. It identifies the distinct areas of the material like appearance, usability, compatibility and dimension.

Quality Assurance: 

Quality assurance involves implementing a comprehensive quality management system encompassing all OSD manufacturing aspects. It includes establishing standard operating procedures (SOPs), documentation control, deviation management, change control, and compliance with regulatory guidelines. All these processes necessitate the need for pharmaceuticals to meet all the quality control standards in order to further meet their intended use.

Process Validation:

Process validation is conducted to demonstrate that the manufacturing processes consistently produce OSD forms of the desired quality. It necessitates conducting tests to ensure the reliability and reproducibility of the manufacturing processes that have an impact on the quality of the products. The tests include viz. validation studies, including equipment qualification wherein a series of tests are conducted to ensure reliable performance of each piece of equipment –  User Requirement Specification (URS), Design Qualification (DQ), Factory Acceptance Test (FAT) at manufacturers’ site, Site Acceptance Test (SAT) at the user site, Installation Qualification (IQ), Operation Qualification (OQ) and Performance Qualification (PQ). Process qualification is an act to conform to the standard compliances and evaluate the process sustainability, and cleaning validation aims to establish a high degree of assurance for due prevention and control of product contaminants.

Regulatory Compliance: 

OSD manufacturing must comply with Good Manufacturing Practices (GMP) guidelines for pharmaceuticals. This compliance is a stamp of approval that the technique and processes correspond to the quality practices. The guidelines address the maintenance of proper documentation, record-keeping, facility design, personnel training, and adherence to safety and environmental regulations.

Thus, our successful OSD processing results from our expert blend of scientific knowledge, advanced technology, and adherence to regulatory standards.

As a pharmaceutical engineering firm dedicated to meticulous planning and diligent processing, we help pharmaceutical companies produce safe, effective, high-quality oral solid dosage forms for patients and accomplish our collective goal for better healthcare. From single units for lab and pilot production to complete production lines for powder processing and oral solid dosage forms, our specialists work with you to understand the unique needs of your pharmaceutical manufacturing plant project and provide innovative solutions so you can get to the market through cost-effective ways in the shortest time possible.

Much like our complete OSD production line, we give complete solutions for Turnkey Pharmaceutical Projects, i.e. from Start to Finish and everything in between.