Senior/Principal Process Development Scientist - HPAPIs

About the role

The Senior/Principal Process Development Scientist - HPAPIs drives the development and optimization of robust, scalable synthetic processes for small molecule APIs—with a focus on highly potent active pharmaceutical ingredients (HPAPIs), payloads, linkers, and payload-linker intermediates—from early development to technology transfer into manufacturing in a fast-paced CDMO environment.

The role involves writing and reviewing technical documents such as SOPs, training modules, technical transfer documents, specifications, and development reports for clients or regulatory filings. It requires ensuring complex technical information is well understood by team associates, management, and clients, while demonstrating leadership in Sterling’s core competencies.

Expertise is required in developing synthetic routes and scalable manufacturing processes for highly potent compounds, including antibody-drug conjugate (ADC) payloads, linker technologies, payload-linker intermediates, and related HPAPI molecules, with a strong focus on safety, containment, and successful transfer into cGMP manufacturing environments.

Responsibilities

• Design, plan, and execute process development and optimization for HPAPIs, payloads, linkers, payload-linker intermediates, and small molecule APIs, owning synthetic strategy through to robust, scalable processes with minimal supervision.
• Perform process characterization using techniques such as Design of Experiments (DOE) and impurity fate/purge studies to understand and control critical process parameters, including those relevant to highly potent compounds and payload-linker syntheses.
• Oversee and support lab-to-plant scale-up activities, providing on-site support for critical operations and troubleshooting, collaborating with analytical, quality, EHS, and manufacturing teams to ensure programs are delivered right first time while meeting containment and safe handling requirements.
• Execute synthesis activities from gram to multi-kilogram scale (up to 20 L), including routine maintenance and troubleshooting of laboratory equipment, containment systems, and engineering controls for handling HPAPIs and payload-linker intermediates.
• Isolate and purify products and intermediates using standard laboratory techniques, including automated preparative chromatography systems.
• Design multi-step synthetic processes from commercially available starting materials to target compounds, including ADC payloads, linker molecules, payload-linker intermediates, highly potent cytotoxic agents, and related pharmaceutical compounds.
• Perform routine analytical procedures (e.g., TLC, GC, NMR, HPLC, LC-MS, KF) to monitor reaction progress, interpret data, and communicate results, including assessment of impurity profiles and product quality attributes.
• Prepare project documentation such as development reports, material specifications, containment assessments, and technology transfers of high technical complexity with minimal supervision.
• Serve as the chemistry technical lead and point of contact for client technical representatives during project meetings, technical reviews, and site visits.
• Establish and coordinate activities at contract chemical and analytical laboratories as required.
• Ensure timely completion and compliance with cGMP, safety, and all other relevant company training requirements.
• Provide technical leadership in the safe handling, process development, scale-up, and manufacture of HPAPIs, payloads, and linker technologies, while mentoring, training, and coaching junior scientists.
• Contribute to the evaluation, implementation, and continuous improvement of containment strategies, risk assessments, and operational practices associated with highly potent compounds.

Requirements

• Understands reaction mechanisms and can apply them to practical execution of synthesis.
• Knowledge in handling, analyzing, and characterizing chemicals, pharmaceuticals, HPAPIs, ADC payloads, linker molecules, payload-linker intermediates, and related organic molecules.
• Proficiency in hands-on execution of analytical techniques such as HPLC, GC, NMR, etc.
• Technical ability to independently design and execute non-routine experiments.
• Ability to analyze data, interpret experimental outcomes, and propose follow-up actions with minimal supervision.
• Demonstrated understanding of containment practices, occupational exposure controls, risk assessments, and safe handling procedures for highly potent compounds.
• Knowledge of synthetic route design, process optimization, impurity control strategies, and scale-up considerations for HPAPIs.
• Ability to read, analyze, and interpret professional journals, technical procedures, and governmental regulations, and to write reports, business correspondence, and procedure manuals.
• Ability to effectively present information and respond to questions from groups of managers, clients, customers, and the public.
• Ability to perform complex math functions, compute ratios, rates, and percentages, and interpret graphs and charts.
• Strong working knowledge of GMP principles and expectations for HPAPI and API development, as well as relevant regulatory requirements.
• Competency with IT systems and Microsoft Office (Outlook, PowerPoint, Word, Excel).

Qualifications

• Demonstrated experience in synthetic route development, reaction optimization, and scale-up for HPAPIs and payload linkers.
• Demonstrated experience working with highly potent compounds, including knowledge of containment strategies, occupational exposure controls, and safe laboratory practices.
• Bachelor’s degree in Chemistry or related field with a minimum of 15+ years of experience, or Master’s degree in Chemistry or related field with a minimum of 9+ years of experience, or PhD in Organic Chemistry or related field with 5+ years of experience.
• The level of this position (Senior or Principal Scientist) will be determined based on the candidate’s experience.

Preferred Qualifications

• Experience working within a CDMO or other fast-paced development environment.
• Experience supporting development and scale-up of ADC payloads, linker technologies, payload-linker intermediates, or other highly potent pharmaceutical compounds.
• Track record of mentoring or managing junior scientists in a laboratory environment.

Schedule

Travel requirement: Up to 5%.

Benefits

• Competitive compensation and benefits package.
• Medical, dental, vision, and life insurance.
• Paid time off.
• Bonus program.
• 401k match.
• Tuition reimbursement.
• 24/7 employee assistance program.
• Flexible work hours.
• Opportunities for career training and development.

Location

This position is located in Germantown, WI, a vibrant city northwest of Milwaukee in Southeast Wisconsin. The area offers a variety of activities and a diverse cultural scene, making it a great place to live, work, and raise a family.

About the Company

Sterling Pharma Solutions is a global contract development and manufacturing organization (CDMO) with over 50 years of experience in developing and manufacturing Active Pharmaceutical Ingredients (APIs). The company also provides Antibody Drug Conjugate (ADC) research and development bioconjugation services.

With facilities in the UK, Europe, and the US, Sterling employs more than 1,300 talented and passionate people who support customers in bringing new medicines to market, improving and saving the lives of patients.

The company’s culture emphasizes delivering exceptional science and service, with a supportive team working toward shared goals. Sterling is an equal opportunity employer.