The demand for small-scale fill-finish services is rapidly expanding as the pharmaceutical industry shifts toward more personalized and targeted therapies.
This development is driven by the rise of personalized medicine, orphan drugs, and advanced biologics, each requiring highly flexible and precise manufacturing capabilities. According to the Global Data database, in August 2025, there were over 2,000 gene therapy drugs in development with just 14 on the market, and greater than 8,500 injectable biologics in development with 3,857 on the market. Early-phase clinical trials and rapid responses to emerging public health needs, such as vaccines and emergency therapeutics, also demand flexible, small-scale fill-finish capabilities to ensure timely and efficient delivery to patients.
For niche therapies, each vial, syringe, and cartridge is critical, making the choice of a fill-finish contract development and manufacturing organization (CDMO) a pivotal decision. When it comes to these high-value, low-volume drugs, every dose matters, creating unique challenges for drug developers.
Many CDMOs are optimized for large-scale manufacturing and are often unable to accommodate smaller projects. In contrast, CDMOs who focus specifically on small-scale production are better suited to handle limited batch sizes with greater precision and minimal product loss. The success of these smaller-scale operations rely heavily on several factors: the technical proficiency of the team, their ability to plan strategically, deep experience in aseptic GMP manufacturing, and strong risk management skills to navigate complex challenges.
In this article, we’ll explore the critical considerations for choosing a fill-finish partner for small-scale batches, from specialized equipment and quality systems to responsive project management and regulatory support. Pharma companies who are producing small batches need a partner who understands that small batch manufacturing isn’t a limitation; it’s a necessity for innovation.
Key Considerations When Choosing a CDMO for Small Batches
Choosing the right CDMO for small-batch fill-finish projects requires careful consideration of several critical factors, each directly impacting the quality, efficiency, and speed of drug development.
Low loss filling strategies
For small batches, every drop counts. Many of these therapies are produced in limited quantities due to the substantial time and cost required to manufacture the drug substances. It is crucial to choose a CDMO with a filling line that is designed for minimal loss.
CDMOs can reduce drug loss through a variety of methods, including reducing the amount of tubing used in filling. To learn more about methods to limit losses in drug manufacturing, read our recent article, Cutting losses in drug manufacturing: A new era in fill-finish technology.
An innovative solution for reducing loss
Sharp Sterile Manufacturing’s low loss filler is specifically designed to minimize product loss, ensuring that the majority of each high-value batch reaches patients. This innovative line is designed to fill batches of less than 1L of product with fewer than 30 mL of product loss between line losses, filter holdup, and transfer loss. Sharp Sterile’s team has produced batches with bulk product volume as low as 100 mL. By reducing waste, this filling line supports clients in maximizing their product yield and minimizing costs, which can be a critical advantage for early-stage and niche therapies.
Flexibility in Batch Size and Formats
Small-batch production demands a flexible CDMO capable of efficiently handling very small volumes without compromising product quality. This includes the ability to support a wide range of container types, from traditional vials to pre-filled syringes and cartridges, ensuring the right format for each therapeutic application. Such versatility is essential for addressing the diverse requirements of personalized medicines, orphan drugs, and complex biologics.
Sterility Assurance and Contamination Control
Maintaining the highest standards of sterility is non-negotiable for small-batch manufacturing, where even minor contamination can have significant consequences. Advanced isolator technology and fully automated systems are critical for minimizing contamination risks. Additionally, robust environmental monitoring and well-maintained cleanroom operations are essential to uphold sterility throughout the manufacturing process, ensuring each dose meets the strictest quality requirements.
Experience with Complex Products
Small batches often involve complex, high-value products, including biologics, highly potent APIs, and temperature-sensitive formulations. The right CDMO will require deep expertise to handle these challenging products, and can provide critical support, from formulation to final fill, ensuring product stability and efficacy.
Look for a CDMO that has experience in adjusting their process to protect both temperature-sensitive and shear-sensitive drugs. To learn more about filling unstable drug products, read our article, Managing Temperature-Sensitive Drug Products in Fill Finish Operations.
Another green flag is a CDMO that can handle formulation development, manufacturing, and scale up all under one roof. With experience working with these types of therapies, keeping the entire product lifecycle at one site can limit tech transfer risks.
Conclusion
In an industry where precision, flexibility, and speed can make or break a drug development program, choosing the right CDMO for small-batch fill-finish projects is critical. Specialized partners like Sharp Sterile Manufacturing offer the tailored solutions, advanced technologies, and expert support needed to navigate the unique challenges of small-scale production.
From early-phase clinical trials to commercial-scale manufacturing, we focus on flexible, low-loss filling, rigorous sterility assurance, and rapid project execution to help our clients bring their innovative therapies to market efficiently and confidently.
