API Manufacturing

Scalable small molecule API manufacturing, from grams to tons

As small molecule complexity continues to rise, we deliver our customers the scientific and engineering expertise they need to develop and deliver scalable and innovative solutions for active pharmaceutical ingredient manufacture, from pre-clinical to commercialisation.

API Manufacturing at Sterling

The rapid pace of innovation in small molecule development today calls for an equally dynamic approach to API manufacturing. With a 50+ year track record as a leading small molecule API manufacturer, we combine our team’s scientific and engineering expertise with close collaboration to help our customers solve complex challenges in the manufacturing process, maintain a secure supply chain and transparency through every stage of programme design and execution, and uphold the exceptional quality they should expect from a partner.

Our flexible and tailored approach to API manufacturing enables us to support even the most specialised and complex project requirements. Our facilities in the UK and US are equipped with state-of-the-art API manufacturing equipment to support a wide range of project requirements. We have the capabilities and expertise to offer our customers manufacturing support for a wide range temperatures, pressures, vacuums, and other technical demands. ... Read more

Core to our API manufacturing capabilities are our dynamic facilities, which are well-equipped to support a broad range of technical requirements for active pharmaceutical ingredient manufacturing processes.

Our comprehensive facilities for API manufacture feature: 

  • 10L and 20L small scale cGMP hydrogenation equipment
  • cGMP kilo laboratory facilities at 10, 20, 25, 50, 100 and 200L for clinical and commercial API batches up to 20 kg
  • High potency capability of 10 – 100L for batch size up to 10 kg
  • Broad range of intermediate and API trains from 200 – 14,800L scale
  • Range of pressure filters, centrifuges and filter driers
  • USP purified water system
  • Cryogenic capability (-90°C)
  • High temperature capability (+200°C)
  • High vacuum WFE/SPE unit and fractionating unit with 30 theoretical plates
  • Hydrogenation vessel from 10 – 4500L scale
  • Range of milling facilities in cleanroom environment
  • Extensive range of capabilities including fluorination, hydroxylamine, organometallic, Friedel-Crafts and carbonylation
  • Systems to deliver bulk Br2 Cl2 H2, ethylene oxide, propylene oxide
  • Controlled substance manufacturing for Schedule I, II, III and IV Read less

Fast Facts

50+ year track record:
We have been a leading small molecule API manufacturer for more than 50 years.

Six facilities:
Our cGMP facilities are equipped with technologies and capabilities to support a diverse range of API manufacturing requirements.

Specialised capabilities:
We are capable of handling highly specialised API manufacturing programmes, supporting fluorination, hydroxylamine, organometallic, Friedel Craft, carbonylation, and more.

Outstanding safety and compliance:
We uphold stringent HSE standards in line with our ZeroHarm initiative to ensure that products are produced safely for both people and planet.

Seamless process design and scale-up

Scaling up an API from small to commercial-scale batches is highly complex, bringing about an entirely new set of process and safety considerations. Our operations and engineering teams have extensive experience scaling our customers’ products from grams to tons, while maintaining the highest standards of quality and safety along the way. ... Read more

We are dedicated to providing our customers full-lifecycle support, from discovery through commercialisation. Our New Product Introduction (NPI) team and processes ensure the successful transfer of your product from the lab to the production plant. We offer end-to-end services in API development and manufacturing with, flexibility, transparency, and quality. Read less

Expert engineering teams

Our engineering team has extensive expertise in working with customers to overcome complex challenges and deliver repeatable and scalable quality in API manufacturing.  Each customer project is assigned a dedicated process engineer to ensure streamlined communication every step of the way. ... Read more

Our engineers work closely with our customers and our chemists to develop tailored, flexible engineering solutions and successfully bring projects from the lab, to the plant, to the commercial scale. Our multi-disciplinary team is widely known among our customer base for its deep experience, commitment to transparency, and passion for customer success. Read less

Comprehensive hazard evaluation

We know that as the scale of a project increases, so does the potential for hazard. We have over 50 years of experience in hazardous chemistry, and we adhere to stringent safety standards in all of our API manufacturing processes. Our hazardous chemistry services are supported by a hazard evaluation laboratory where we integrate our process engineering and chemistry expertise to ensure the safety and success of your project. ... Read more

Committed to protecting our people and our planet, we carry out robust hazard evaluation at the onset of every manufacturing project and ensure the proper safeguards and engineering controls remain in place throughout its entirety. Our hazardous chemistry expertise enables us to safely scale up reactions involving diazomethane, chlorination, bromination, hydrogenation, and much more. Read less

Repeatable quality at the commercial scale

In a highly regulated industry, it is critical to ensure the safety and quality of your products and processes, as well as that of the patients these drugs will eventually help. Our quality team ensures that your product’s manufacturing processes adhere to cGMP standards throughout the entire product lifecycle. They are also responsible for making sure that all manufacturing processes are carried out correctly and as planned, while adhering to our customers’ desired timelines. ... Read more

As a leading API manufacturing company, we have a deep knowledge of regulatory requirements around the world, and our facilities have undergone successful cGMP inspections with the FDA, MHRA and PMDA. We have supported our customers in their regulatory filings for many years, including compiling data on our customers’ behalf for CMC submissions. Click for more on compliance. Read less

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