Senior Associate Scientist
- United States - Washington – Bothell
Use Your Power for Purpose
At Pfizer, our purpose is to deliver breakthroughs that change patients’ lives. As a Senior Associate Scientist Biology, you will be at the forefront of our mission, contributing to the development of innovative therapies and vaccines that have the potential to transform patient care. Reporting to the Research & Development division, you will leverage advanced science and cutting-edge technologies to make a tangible impact on global health. Your work will be instrumental in ensuring drug safety and efficacy, supporting clinical trials, and accelerating the delivery of top-tier medicines to patients worldwide.
What You Will Achieve
In this role, you will be part of Pharmaceutical Research and Development, supporting Pfizer’s biotherapeutics portfolio, contributing to the development of parenteral formulations for antibody–drug conjugates (ADCs) and monoclonal antibodies (mAbs), with potential to work on proteins and other biologics.
You will perform formulation development and analytical characterization of candidate molecules and formulations using a range of biophysical and biochemical techniques. You will also support drug product manufacturing process development and be responsible for data compilation, presentations, and technical report writing.
A strong foundation in scientific principles and best practices will enable you to meet critical deadlines and deliver high‑quality work. As a technical contributor, you will assess assigned tasks and make informed decisions through the direct application of your expertise. Your dedication will help Pfizer reach new milestones and ultimately improve the lives of patients worldwide.
How You Will Achieve It
The responsibilities of the Senior Associate Scientist position include, but are not limited to:
Support development of parenteral formulations and manufacturing processes for ADCs and mAbs.
Characterize candidate molecules and formulations to establish stability profiles using a broad range of biophysical and biochemical techniques (e.g., U/HPLC, imaged capillary electrophoresis (iCE), capillary gel electrophoresis (CGE), spectroscopy).
Assist with scale-up of drug product processes (fluid handling, sterilizing filtration, lyophilization) from bench to pilot scale and support technology transfer to manufacturing facilities.
Collaborate within team and cross‑functionally to advance formulation optimization and candidate progression.
Summarize data, prepare presentations, and author technical reports to communicate results.
Here Is What You Need (Minimum Requirements)
Bachelor’s degree (BA/BS) in Biochemistry, Chemical or Biochemical Engineering, Pharmacy, Chemistry, Biology, or a related discipline with at least 2 years of relevant experience, or a Master’s degree in a relevant discipline with 0+ years of experience.
Hands‑on laboratory experience with a variety of analytical techniques, which may include UPLC (SEC, IEX), capillary gel electrophoresis (CGE), imaged capillary electrophoresis (iCE), and spectroscopic methods.
Excellent problem‑solving and critical‑thinking skills used to solve scientific problems using experimental techniques, with contemporaneous recording of experimental details and data in an electronic laboratory notebook (ELN).
Ability to effectively communicate (oral and written) and collaborate, with experience working within multidisciplinary project teams
Strong attention to detail and a high level of accuracy in scientific work and documentation
Strong organizational and time‑management skills.
Proficiency with general computer software, including word processing, spreadsheets, and presentation tools.
Bonus Points If You Have (Preferred Requirements)
Experience in formulation and process development for lyophilized ADC and/or mAb drug product
Hands-on experience with analytical techniques such as SE‑UPLC, RP‑UPLC, Karl Fischer titration, differential scanning calorimetry (DSC), freeze-drying microscopy (FDM), dynamic light scattering (DLS), etc.
Knowledge of current U.S. and global regulatory requirements, including FDA and ICH guidance.
Experience using common AI‑enabled tools, including generative technologies such as ChatGPT or Microsoft Copilot, to support problem solving and enhance productivity.
PHYSICAL/MENTAL REQUIREMENTS
This is an on-site lab-based position and incumbent must be able to perform all lab-based duties.
NON-STANDARD WORK SCHEDULE, TRAVEL OR ENVIRONMENT REQUIREMENTS
Some travel expected to support work across other Pfizer sites or CMO/CDMO network.
Additional Information:
- Work Location Assignment: On Premise
- Last Day to Apply: May 15, 2026
Relocation assistance may be available based on business needs and/or eligibility.

Candidates must be authorized to be employed in the U.S. by any employer.
U.S. work visa sponsorship (such as TN, O-1, H-1B, etc.) is not available for this role now or in the future.

Sunshine Act
Pfizer reports payments and other transfers of value to health care providers as required by federal and state transparency laws and implementing regulations. These laws and regulations require Pfizer to provide government agencies with information such as a health care provider’s name, address and the type of payments or other value received, generally for public disclosure. Subject to further legal review and statutory or regulatory clarification, which Pfizer intends to pursue, reimbursement of recruiting expenses for licensed physicians may constitute a reportable transfer of value under the federal transparency law commonly known as the Sunshine Act. Therefore, if you are a licensed physician who incurs recruiting expenses as a result of interviewing with Pfizer that we pay or reimburse, your name, address and the amount of payments made currently will be reported to the government. If you have questions regarding this matter, please do not hesitate to contact your Talent Acquisition representative.
EEO & Employment Eligibility
Pfizer is committed to equal opportunity in the terms and conditions of employment for all employees and job applicants without regard to race, color, religion, sex, sexual orientation, age, gender identity or gender expression, national origin, disability or veteran status. Pfizer also complies with all applicable national, state and local laws governing nondiscrimination in employment as well as work authorization and employment eligibility verification requirements of the Immigration and Nationality Act and IRCA. Pfizer is an E-Verify employer. This position requires permanent work authorization in the United States.
Pfizer endeavors to make www.pfizer.com/careers accessible to all users. If you would like to contact us regarding the accessibility of our website or need assistance completing the application process and/or interviewing, please email disabilityrecruitment@pfizer.com. This is to be used solely for accommodation requests with respect to the accessibility of our website, online application process and/or interviewing. Requests for any other reason will not be returned.
Breakthroughs that change patients’ lives
Research confirms what intuition tells us: that purpose-driven companies perform better, are more innovative, attract and retain the best people, and know how to unleash the power of those people. Pfizer’s purpose—Breakthroughs that change patients' lives—fuels everything we do and reflects our passion for building on our legacy as one of the greatest contributors of good to the world.
Each word in our purpose has meaning and reflects the value we strive to bring to patients and society:
“Breakthroughs” - These are the innovations, scientific and commercial, that we seek to deliver every day. All colleagues, regardless of role, level or location, strive for breakthroughs every day.
“Change” - We want to do more than simply improve patients’ medical conditions; we want to dramatically change their lives for the better.
“Patients’ lives” - We consider not only patients, but everyone they touch—including their families, caregivers, and friends—and everything they love to do. It’s an intentionally holistic view.
Our purpose ensures that patients remain at the center of all we do. We live our purpose by sourcing the best science in the world; partnering with others in the healthcare system to improve access to our medicines; using digital technologies to enhance our drug discovery and development, as well as patient outcomes; and leading the conversation to advocate for pro-innovation/pro-patient policies.
Every decision we make and every action we take is done with the patient in mind—and to nurture an environment where breakthroughs can thrive.
Our Values
To fully realize Pfizer’s purpose, we have established a clear set of expectations regarding “what” we need to achieve for patients and “how” we will go about achieving those goals.
The “how” is represented by four simple, powerful values—courage, excellence, equity, and joy—that define our company and our culture.
Courage: Breakthroughs start by challenging convention, especially in the face of uncertainty or adversity. This happens when we think big, speak up, and are decisive.
Excellence: We can only change patients’ lives when we perform at our best together. This happens when we focus on what matters, agree who does what, and measure our outcomes.
Equity: We believe that every person deserves to be seen, heard, and cared for. This happens when we are inclusive, act with integrity, and reduce healthcare disparities.
Joy: We give ourselves to our work, but it also gives to us. We find joy when we take pride, recognize one another, and have fun.
Pfizer Research & Development
Pfizer Research & Development serves as the beating heart of Pfizer's trailblazing product pipeline, the essence of our mission to bring life-changing medicines to the world.
With an unwavering commitment to innovation, we use a multidisciplinary approach that blends scientific expertise, cutting-edge technologies, and strategic collaborations, igniting a powerful engine that propels groundbreaking discoveries into life-saving treatments for patients in need.
Through our relentless pursuit of progress, we envision a future where cutting-edge medicines pave the way to healthier, happier lives worldwide.
Benefits at Pfizer
Pfizer offers competitive compensation and benefits programs designed to meet the diverse needs of our colleagues. Our Pay for Performance Philosophy and Practices reward colleagues based on the contributions they make to our business.
Our Competitive Benefits Programs help our colleagues by:
- Promoting Health and Wellness to help colleagues maintain and improve their physical and mental wellbeing. Pfizer offerings include health and disability insurance, preventative health programs, medical screenings, free or reduced-cost vaccinations, discounts on Pfizer products, mental health support, nutrition and fitness counseling and more.
- Strengthening Colleagues’ Financial Security by providing company contributions to retirement plans, life insurance and financial planning education to help colleagues achieve their financial goals.
- Providing Benefits and Time off for the Moments that Matter to ensure Pfizer colleagues have the time away from the office to recharge, recover and return to work as the best version of themselves. Vacation, Holiday time and Sick time are just the beginning, with a 12 week parental leave policy for both parents of a new born, 10 day of caregiver leave for those times when your family needs you whether it’s a child, spouse or parent, bereavement leave, and additional country-specific programs.
- And so much more, depending on your country and site, Pfizer offers childcare facilities or discount programs, on-site health and/or fitness centers, movement and mindfulness solutions, “Log in for your Day” work flexibility and so much more.
For U.S. based jobs, view an overview of Pfizer’s U.S. benefits program (opens in a new window)