The role of process filtration in the pharmaceutical industry

Process filtration is essential in pharmaceutical manufacturing to ensure finished products are safe and effective for patients. Different stages of pharmaceutical production are vulnerable to diverse types of contamination that can compromise product quality and patient safety, cause regulatory non-compliance, and result in sales losses of up to $600,000 in some cases. Critical pharmaceutical processes such as water treatment, API production, and fermentation require robust process filtration, and selecting appropriate filter types is essential for meeting regulatory expectations, particularly for sterility.

At Atlas Copco, we provide comprehensive process filtration solutions across pharmaceutical production, helping manufacturers ensure their products are safe, effective, and compliant. This page outlines key filtration considerations across critical manufacturing processes to support production teams in meeting regulatory requirements.

The primary role of process filtration is to ensure contaminants are not present in pharmaceutical products. Contaminants take many forms and pose serious risks to drug safety and efficacy. Microbial contamination, for example, can cause infections and inflammatory responses while also reducing treatment effectiveness. In 2023, eye drops contaminated with a drug-resistant strain of Pseudomonas aeruginosa caused multiple deaths and permanent vision loss in some cases, highlighting the severe consequences of failures in sterility control.

Particles like plastic, metal, glass, and process aggregates can enter products during manufacturing. In one case, calcium phosphate particles in an IV-administered nutrition product were linked to deaths from respiratory distress. In addition to patient injury and loss of life, contamination can result in serious regulatory action and significant reputational damage for manufacturers. Regulatory authorities emphasise process filtration as a key element of contamination control, with specific guidance on validating filtration systems to demonstrate effective removal of defined contaminants.

Contamination can arise from many sources, including equipment, personnel, raw materials, gases, water, and steam. The following sections review contamination risks in key pharmaceutical production processes and describe how appropriate process filtration strategies help to address them.

Water is a fundamental component of pharmaceutical manufacturing and undergoes extensive treatment from municipal supply to its use in products and production processes. Early-stage prefiltration lowers particulate burden in water and safeguards downstream treatment processes, including softening, reverse osmosis, and sterile filtration. Pleated fiber filters are often used at this stage. Preparation of water for injection (WFI) requires additional particulate filtration to remove contaminants and any resin fines released during ion exchange. This is typically followed by sterilizing-grade filtration using 0.22 µm filters to meet regulatory sterility requirements. Sterilization grade pleated membrane filters such as polyethersulfone (PES) and hydrophilic polyvinylidene fluoride (PVDF) filters are suitable for water sterilization while polytetrafluoroethylene (PTFE) vent filters provide sterility for gas exchange in WFI storage tanks before use.

API manufacturing relies on diverse inputs, such as water, ingredients, and air exchange during storage and formulation, all of which have the potential to introduce contaminants. Consequently, water undergoes filtration to remove particulates and bioburden before reactor entry. This is important as even with robust prefiltration, potential contaminants such as fibres and microbiological contaminants can enter water during storage. Atlas Copco provides SMT-G polytetrafluoroethylene (PTFE) vent filters for sterile gas exchange in stored water systems and formulation reactors, helping preserve product quality and support GMP compliance. Sterilization filtration is performed following formulation to ensure sterility of the product prior to filling.

Fermentation reactors are particularly vulnerable to microbial contamination as they create ideal conditions for the growth of diverse microorganisms. Furthermore, fermentation processes require diverse inputs each with different filtration demands. These include active ingredients, compressed gases, and purified water, while sterile venting is needed to control reactor pressure. Prefiltration followed by sterile filtration of these inputs helps to ensure that only the desired microorganisms grow within the reactor. Our MSS stainless steel filters help to purify sterilizing steam for fermentation equipment, helping maintain reactor sterility before process inputs are added.

Process filtration safeguards pharmaceutical quality across core processes, including water purification, API production, and fermentation. By removing microbial and particulate contaminants at critical control points, validated process filtration systems protect patient safety, maintain product efficacy, and support regulatory compliance.

At Atlas Copco, we assist manufacturers in selecting and implementing fit-for-purpose filters across production streams, helping to reduce contamination risk, prevent costly recalls, and consistently deliver safe, effective medicines to patients worldwide.