Custom API manufacturing from early development to commercial
As a leading global API CDMO, Siegfried provides integrated process development, analytical development, scale-up, GMP manufacturing, and regulatory support for innovative drug substances – from early phase development to commercial supply.
Your trusted partner for exclusive synthesis
Our wide range of services for custom API synthesis
Flexible API contract synthesis from gram to ton scale
Our global manufacturing network scales seamlessly with your program – from gram quantities for early development to commercial-scale production. As your integrated CDMO partner, we manage route design, process development, scale-up, and commercial supply of your drug substance, with seamless transfer into our drug product network to accelerate your path to market
Preclinical and early phase development
At our Siegfried Acceleration Hub in the US we offer comprehensive services for preclinical and early-phase drug development and manufacturing. From phase-appropriate analytical and validation method development to scalable manufacturing processes, we provide the capabilities and support needed to accelerate your path from concept to clinic. Backed with our decades long development and manufacturing experience we ensure a smooth transition into Siegfried’s global manufacturing network from early phase through to commercial production, all from a single partner.
Process development for drug substance manufacturing
Siegfried’s process and chemical development services help establish scalable, cost-effective manufacturing processes tailored to your product’s commercial requirements. Our expert scientists design entirely new synthetic routes or optimize existing ones and work closely with you to set clear development objectives.
Analytical development for API custom synthesis
Our analytical development team works hand in hand with process development to support your product at every phase. Together, we develop robust analytical methods and quality control specifications that support every stage of development.
With more than 500 method validations performed in accordance with ICH guidelines and extensive experience in cGMP compliance, we advise on purity profiles, impurity tracking, limits, structure determination, genotoxic contamination, and heavy metal analysis.
Pilot manufacturing and scale-up in API contract manufacturing
Building on experience from more than 1,600 chemical development projects, we take chemical processes from development and scale them up into robust manufacturing processes. We support your program from early clinical trials through commercial launch and routine manufacturing.
Our versatile cGMP pilot manufacturing and scale-up capabilities at our production sites in Zofingen, Evionnaz, Nantong, and Pennsville accelerate your drug development.
GMP API manufacturing
As your flexible partner, Siegfried provides reliable, consistent commercial supply of high-quality drug substances. Versatile cGMP capabilities and robust, market-tailored processes enable us to manufacture demanding APIs, intermediates, and complex syntheses, including controlled substances and high-potency materials, alongside our API portfolio of generic products.
Regulatory documentation and DMF support
Siegfried prepares, maintains, and submits cGMP-compliant documentation that keeps your filings moving. We author and update Drug Master File (DMF) modules and submission dossiers for global regulatory authorities, including the FDA, EMA, and PMDA, and manage lifecycle updates as your process evolves. Our Siegfried Acceleration Hub supports CMC sections and route scouting from the very first phase.
Analytical methods, validation reports, stability data, and specifications are prepared and provided in a format suitable for submission to international regulatory authorities, offering your regulatory affairs team submission-ready packages from day one.
Technical capabilities for exclusive drug synthesis
Advanced chemistry and process capabilities
Siegfried’s state-of-the-art laboratories and manufacturing facilities support a broad range of chemical and enzyme-catalyzed transformations, enabling efficient development and manufacture of complex drug substances. Our process capabilities cover reaction conditions from –100°C to 300°C and 1 mbar to 40 bar, providing the flexibility required for a wide variety of synthetic routes.
State-of-the-art laboratories
Advanced laboratory automation accelerates process development and deepens process understanding, while dedicated, segregated laboratory facilities enable the safe handling of highly potent compounds with occupational exposure limits (OEL) down to 1 µg/m³.
Particle engineering and solid-state expertise
Our expertise extends beyond synthesis to the critical downstream operations that determine product quality and performance. We optimize crystallization and isolation processes to maximize yield and purity and offer a comprehensive range of particle engineering technologies, including milling, spray drying, micronization, and pre-formulation blending, to achieve the desired physical characteristics.
Scalable manufacturing and technology transfer
Successful commercialization depends on robust and scalable processes. Our process development teams establish safe, sustainable, and economically viable manufacturing routes designed for seamless scale-up. Through our collaboration with the Miniplant 4.0 Association, we leverage advanced digital tools and process insights to accelerate technology transfer and manufacturing readiness.
Comprehensive analytical capabilities
Our chemical and process development capabilities are supported by a comprehensive analytical infrastructure, including HPLC, UPLC, GC, LC-MS, GC-MS, ICP-MS, NMR, IC, DSC/TGA, UV, IR, NIR, Raman spectroscopy, and advanced particle size analysis.
All analytical data, methods, specifications, and reference standards are managed within a validated Laboratory Information Management System (LIMS), ensuring data integrity, regulatory compliance, and submission-ready documentation.
Our global manufacturing network for custom APIs
Europe
Zofingen
Zofingen is the headquarters of the Siegfried Group and one of Siegfried’s two launch sites for newly developed processes. The production site specializes in the development and commercial manufacturing of active pharmaceutical ingredients (APIs) and intermediates, including high potency APIs. Founded in 1873, the site has a broad portfolio of technological capabilities including hydrogenation, organometallic and hydride chemistry, halogenation, methylation, milling and micronization and more. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Active pharmaceutical ingredients (API) and intermediates
- Highly active and controlled substances
- Custom synthesis

4800 Zofingen Switzerland
Evionnaz
Siegfried Evionnaz is one of Siegfried’s two launch sites for newly developed processes. It specializes in custom synthesis of active ingredients and intermediates for the pharmaceutical industry. With an R&D Center housing advanced chemical and analytical facilities, state-of-the-art laboratories, and cutting-edge technologies, it offers chemical process R&D and analytical development services for Siegfried’s global Drug Substances network. Established in 1957, the site has a broad portfolio of technologies including micronization, azide chemistry, hydrogenation, halogenation, organometallics, cryogenics, and more. Focused on niche technologies, the facility possesses development capacity from 1 gram to industrial-scale production. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Active pharmaceutical ingredients (API) and intermediates
- Custom synthesis

1902 Evionnaz
Switzerland
Zurich
DINAMIQS, a Siegfried company, is a science-driven Contract Development and Manufacturing Organization offering end-to-end viral vector manufacturing solutions to accelerate gene therapy projects from DNA design to commercial scale. DINAMIQS offers a comprehensive and customized range of manufacturing services, process development, quality control and analytics solutions for genetic medicine companies.
Competencies
- Viral vectors

Hameln
Siegfried Hameln is one of Siegfried’s six Drug Products sites globally. It is a leading manufacturer of parenteral solutions, producing a wide range of aseptic and terminally sterilized products in ampoules and vials, with a dedicated development center for sterile injectables. Its specialization lies in the production of complex formulations, including anesthetics, flammable substances, oxygen-sensitive liquids, and cold chain products, all while ensuring strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards. The site has a broad portfolio of technological capabilities including cold-chain handling, automated visual inspection and packing and more. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Sterile and aseptic filling of ampoules and vials
- Biologics and small molecules

Minden
Siegfried Minden is one of Siegfried’s five run and deliver sites for established processes. It specializes in synthesis of active ingredients and intermediates for the pharmaceutical industry. Established in 1935 and focused on efficient operations and special technologies, the facility possesses production capacity from approximately 25 kilograms to multi-100-ton-scale production. The site has a broad portfolio of technological capabilities such as hydrogenation, organometallic and hydride chemistry, milling and micronization, halogenation and more. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Active pharmaceutical ingredients (API) and intermediates
- Highly active and controlled substances
- Custom synthesis

Karlstrasse 15
32423 Minden
Germany
St.Vulbas
Siegfried St.Vulbas is one of Siegfried’s five run and deliver sites for established processes. It specializes in synthesis of active ingredients, intermediates and custom synthesis for the pharmaceutical industry. Established in 1993, the site has a broad portfolio of technological capabilities such as organometallic and hydride chemistry, phosgenation, hydrogenation, halogenation and more. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Active pharmaceutical ingredients (API) and intermediates
- Custom synthesis

530 Allée de la Luye
01150 Saint Vulbas
France
Hal Far
Siegfried Malta is one of six Siegfried’s Drug Products sites globally. It specializes in the manufacturing of oral solid dosage forms (OSD), encompassing tablet and capsule formulations with diverse release profiles (IR, SR, DR), formulations and technologies. Established in 2007 as one of the first OSD sites within the Siegfried network, technologies range from dry blends, aqueous and organic – wet/dry granulation (bottom with Wurster technology and top spray), tableting, encapsulation, coating and blister packaging. The facility has the ability to produce manufacturing batch sizes on a mid – large scale, with a focus on tech transfer and scale up activities. All operations comply strictly with quality standards (GxPs), safety, health protection and environmental standards.
Competencies
- Bulk manufacturing and packaging of solid dosage forms for oral applications

Hal Far BBG 3000
Malta
Barberà del Vallès
Siegfried Barberà is one of Siegfried’s six Drug Products sites globally. It specializes in manufacturing and packaging solid oral dosage forms (OSD), including high-potency and inhalation capsules for treating respiratory diseases. Established in 1994, the site supplies products worldwide including Japan and the USA. It has a dedicated Development Center offering development and scale-up services for solid dosage forms and inhalation capules. The site has a wide range of equipment to produce solid formulations on a small and large scale, with blister, bottle and wallet/Shellpak packaging forms. Its state-of-the-art production equipment integrates Industry 4.0 technologies, such as digitization, system integration, robotics, and automation, ensuring precise processes. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Bulk manufacturing and packaging of solid dosage forms for oral applications including high potency
- Inhalation capsules for medical devices to treat respiratory diseases

08210 Barberà del Vallès (Barcelona)
Spain
El Masnou
Siegfried El Masnou is one of Siegfried’s six Drug Products sites globally. It has a long track record of expertise in manufacturing aseptic products, with the site established in 1925. It is the largest factory in Spain specialized in ophthalmic products, both eye drops and sterile eye care ointments, as well as products for nasal and otic use. It has a dedicated Development Center offering development and scale up services focused on sterile ophthalmic products. The site’s technological capabilities include ball milling molturation, pre-use post sterilization integrity testing, and multi-dose round, oval and preservative-free bottles. Processes are fully automated and use cutting-edge technology, embracing Industry 4.0 technologies like system integration, robotics, and extensive automation. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Bulk manufacturing and packaging of sterile ophthalmic products, including eye drops, eye ointments, otic/nasal sprays

08320 El Masnou (Barcelona)
Spain
USA
Pennsville
Siegfried Pennsville is one of Siegfried’s five run and deliver sites for established processes. It is Siegfried’s drug substance manufacturing site for the US market and provides spray drying operations globally. Established in 1928, its main activities are pilot and commercial manufacturing of drug substances (APIs) and intermediates, in a fully cGMP and SHE compliant manner. The site has a broad portfolio of technological capabilities including spray drying, organometallic and hydride chemistry, hydrogenation, milling and micronization and more.
Competencies
- Active pharmaceutical ingredients (API) and intermediates
- Highly active and controlled substances
- Custom synthesis

Pennsville, NJ 08070
USA
Irvine
Siegfried Irvine is one of Siegfried’s six Drug Product sites globally. It is a sterile drug product manufacturing site, specializing in innovative and difficult to manufacture pharmaceuticals, ophthalmics, and drug delivery devices. It provides cGMP sterile drug product fill and finish of biologics, suspensions, emulsions, ointments, and gels in a fully compliant manner. Established in 2002, the site’s technological capabilities include state-of-the-art filling lines for vials, droptainers and prefilled syringes; bulk filling capabilities; and low oxygen, light sensitivity, low humidity and non-aqueous product handling. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Sterile and aseptic filling of large and small molecules

Grafton
The Siegfried Acceleration Hub in Grafton specializes in early-phase development and manufacturing. Established in 1998, the site offers phase-appropriate analytical and development services, regulatory expertise, and regulatory-compliant quality systems — all with the capability to manage highly potent and controlled substances. The Acceleration Hub provides end-to-end life cycle management with services from preclinical through commercial, including scale-up, tech transfer, validation and launch, with seamless transfer into Siegfried’s global network. The site has a broad portfolio of technologies and capabilities, including phase-appropriate preclinical process development, advanced filtration technologies, CMC sections of DMFs, alternate synthesis, route scouting and more. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.

Athens

Wilmington
Siegfried Wilmington, is one of Siegfried’s five run and deliver sites for established processes. It is a large-scale commercial manufacturing facility for innovative products and controlled substances, supporting a wide range of therapeutic applications. Established in 1979, the multi-purpose site today offers 150 cubic meters of reactor capacity with a wide range of technologies, operating to the highest regulatory and quality standards.
Competencies
- Active pharmaceutical ingredients (API), Intermediates, Controlled Substances

Wilmington, DE 19801
USA
Asia
Nantong
Siegfried Nantong is one of Siegfried’s five run and deliver sites for established processes. It specializes in custom synthesis of active ingredients and intermediates for the pharmaceutical industry. Established in 2013, the chemical plant’s technological capabilities include organometallic chemistry, hydrogenation, alkylation, amination, chlorination and milling. All activities are conducted in strict compliance with quality standards (GMPs) and with safety, health protection and environmental standards.
Competencies
- Active pharmaceutical ingredients (API) and intermediates
- Custom synthesis

Nantong City, Jiangsu Province
P.R.C. (post code: 226017)
Australia
Westbury

FAQ: Custom API manufacturing
What is custom API manufacturing?
Custom API manufacturing is the production of an active pharmaceutical ingredient (API) to a customer’s exact specifications. An API CDMO develops or optimizes the synthetic route, manufactures the API under cGMP, and supports every stage from process and analytical development to pilot scale-up, commercial supply, and regulatory documentation.
What is an API CDMO?
An API CDMO (Contract Development and Manufacturing Organization) develops, optimizes, and manufactures active pharmaceutical ingredients for pharmaceutical and biotechnology companies. Services typically include process development, analytical development, scale-up, commercial manufacturing, technology transfer, and regulatory support, helping sponsors move efficiently from early development to commercial supply.
hat is the difference between a CMO and an API CDMO?
A CMO (Contract Manufacturing Organization) primarily manufactures a process provided by the customer. An API CDMO also provides development services, including designing or optimizing synthetic routes, developing analytical methods, scaling manufacturing processes, and supporting regulatory filings before commercial production. Working with a single API CDMO helps reduce technology-transfer risk and simplifies the path from development to commercialization.
What does exclusive synthesis mean?
Exclusive synthesis is the dedicated, confidential manufacture of a proprietary API or intermediate for a single customer. The CDMO develops a tailored manufacturing process and produces the molecule exclusively for that sponsor, rather than supplying a generic catalog product. Siegfried has built its reputation as an exclusive synthesis CDMO, protecting customer intellectual property while delivering scalable, cGMP-compliant API manufacturing.
Is Siegfried's API contract manufacturing cGMP compliant?
Yes. All Siegfried manufacturing sites operate under current Good Manufacturing Practice (cGMP) and are regularly inspected by national and international regulatory authorities. Our API manufacturing capabilities include validated processes, controlled raw materials, comprehensive batch documentation, and independent quality oversight, supporting reliable clinical and commercial supply worldwide.
Does Siegfried provide DMF and regulatory submission support?
Yes. Siegfried prepares, maintains, and submits cGMP-compliant regulatory documentation, including Drug Master File (DMF) modules and submission dossiers for authorities such as the FDA, EMA, and PMDA. Analytical methods, validation reports, stability data, and specifications are provided in submission-ready formats to support efficient regulatory filings across global markets.
Can Siegfried manufacture high-potency APIs (HPAPIs) and controlled substances?
Yes. Siegfried develops, manufactures, and analyzes high-potency APIs (HPAPIs) in dedicated, segregated facilities with occupational exposure limits (OELs) down to 1 µg/m³. We also hold the required national licenses to manufacture controlled substances, enabling us to safely support highly potent and complex molecules from development through commercial production.
What scale of API custom synthesis can Siegfried support?
Our network supports everything from gram quantities for early clinical trials to multi-ton commercial production. Reaction conditions range from -100 °C to 300 °C and 1 mbar to 40 bar, covering a broad chemistry space. We scale your process step by step, keeping it cost-effective and robust as volumes grow from pilot batches to routine commercial supply.
How do I choose the right API CDMO?
When selecting an API CDMO, consider expertise in process and analytical development, cGMP manufacturing, regulatory support, technology transfer, and commercial supply. A global manufacturing network, strong regulatory inspection history, and broad chemistry capabilities help reduce development risk, simplify scale-up, and improve supply security. Siegfried combines these capabilities within one integrated global network.
What is the difference between API manufacturing and drug product manufacturing?
API manufacturing produces the active pharmaceutical ingredient that provides a medicine’s therapeutic effect. Drug product manufacturing formulates the API into the finished dosage form, such as tablets, capsules, sterile injectables, or ophthalmic products. As an integrated CDMO, Siegfried offers both drug substance and drug product manufacturing, enabling seamless technology transfer from API development through commercial finished dosage production.
Where does Siegfried manufacture APIs?
Siegfried operates drug substance competency centers across Europe, North America, Asia, and Australia, including Zofingen, Evionnaz, St. Vulbas, Minden, Nantong, Pennsville, Grafton, Athens, Wilmington, and Westbury. This global footprint supports regional regulatory filings and secure commercial supply close to your target markets.
