SUMMARY/JOB PURPOSE:
The Senior Scientist, Analytical Development, Biologics CMC will support CMC analytical development for biologic therapeutics, with a primary focus on protein characterization using high-resolution mass spectrometry and analytical assay development for antibody-drug conjugates (ADCs). The incumbent will apply deep technical expertise in mass spectrometry, liquid chromatography and electrophoresis to perform assay development and product characterization, and to advance pre-IND and clinical-stage biologics programs.
The individual is expected to work hands-on in the laboratory to develop, optimize, qualify, and transfer analytical methods supporting internal CMC development activities and external CDMO/CTL execution. This role will support extended characterization of ADCs, monoclonal antibodies, bispecifics, and other biologic modalities, including intact and subunit mass analysis, peptide mapping, post-translational modification assessment, sequence confirmation, conjugation site analysis, linker-payload related variant identification, DAR-related characterization, and chromatographic peak identification.
Strong ownership is critical to ensure the speed, cost-effectiveness, and technical quality of our CMC activities. The individual will work independently and in cross-functional teams, and work effectively with third-party CDMOs and partners.
ESSENTIAL DUTIES AND RESPONSIBILITIES:
Serve as a subject matter expert for high-resolution mass spectrometry-based protein characterization of biologics, including ADCs, monoclonal antibodies, bispecific antibodies, and related novel biotherapeutic proteins.
Develop, optimize, and execute LC-MS methods for intact mass, reduced and non-reduced mass analysis, subunit analysis, peptide mapping, PTM identification, sequence confirmation, disulfide mapping, glycosylation assessment, and product variant characterization.
Lead or support assay development for biologics, including methods such as SEC, HIC, RP-HPLC, icIEF, CE-SDS, and residual-free drug analysis
Support ADC-specific characterization, including conjugation site analysis, drug-antibody ratio distribution, linker-payload related variants, conjugatable impurities, payload-related degradation products, and process- or storage-related modifications.
Perform method development and analytical testing to support upstream, downstream, bioconjugation, and formulation process development.
Transfer analytical methods from internal development to CDMOs/CTLs and provide technical oversight for method qualification, validation, and routine testing.
Review and author analytical procedures, SOPs, protocols, technical reports, method qualification/validation documents, and product characterization reports.
Review GMP release and stability testing results, and support OOS/OOT, deviation, change control, and investigation activities related to analytical methods and product quality.
Support CQA assessment and control strategy development by integrating analytical results from mass spectrometry, chromatography, electrophoresis, biophysical characterization, and functional assays.
Support IND/IMPD and other regulatory submission activities, including authoring and reviewing analytical development, characterization, method validation, and control strategy sections.
Collaborate closely with Process Development, DS and DP Manufacturing, Quality Assurance, Regulatory Affairs, Project Management, Discovery, external CDMOs, CTLs, and other partners.
Contribute to building and maintaining internal laboratory capabilities for advanced biologics characterization, including instrument operation, maintenance, troubleshooting, and implementation of new technologies.
Work independently and collaboratively in a fast-paced, matrixed environment while delivering high-quality technical results and documentation.
EDUCATION/EXPERIENCE/KNOWLEDGE & SKILLS:
Education:
Ph.D. in chemistry, biochemistry, analytical chemistry, pharmaceutical sciences, chemical engineering, protein chemistry, or a related field with relevant industry experience; or,
Master’s degree in chemistry, biochemistry, analytical chemistry, pharmaceutical sciences, chemical engineering, protein chemistry, or a related field with 5+ years relevant industry experience; or,
Bachelor’s degree in chemistry, biochemistry, analytical chemistry, pharmaceutical sciences, chemical engineering, protein chemistry, or a related field with 7+ years relevant industry experience; or,
Equivalent combination of education and experience.
Experience:
Demonstrated hands-on experience in protein characterization and structural elucidation using high-resolution mass spectrometry, such as Orbitrap and Q-TOF, is highly desired.
Strong technical experience with LC-MS/MS workflows for intact protein analysis, reduced/subunit analysis, peptide mapping, PTM analysis, disulfide mapping, glycan/glycopeptide analysis, sequence confirmation, and chromatographic peak identification is highly desired.
Experience in analytical assay development for ADCs is strongly preferred, including SEC, HIC, RP-HPLC, icIEF, CE-SDS, DAR-related analysis, and residual-free drug analysis.
Experience in higher order structure analysis, such as SEC-MALS, DSC, FTIR, and CD is a plus.
Knowledge/Skills:
In-depth knowledge of biologics analytical development, protein chemistry, mass spectrometry, chromatography, electrophoresis, and CMC product characterization.
Strong understanding of critical quality attributes for biologics and ADCs, including size variants, charge variants, purity, glycosylation, PTMs, sequence variants, fragmentation, aggregation, conjugation-related attributes, DAR-related species, and linker-payload related variants.
Ability to design scientifically sound studies, interpret complex analytical data, and translate findings into actionable CMC development decisions.
Strong technical writing skills for protocols, reports, SOPs, regulatory sections, and investigation summaries.
Ability to work effectively with cross-functional internal teams and external CDMOs/CTLs.
Excellent communication, presentation, collaboration, and problem-solving skills.
Ability to prioritize multiple programs and deliver high-quality work in a fast-paced environment.
Strong ownership, scientific curiosity, attention to detail, and commitment to technical excellence.
SUPERVISORY RESPONSIBILITIES:
No direct people management responsibility is required. The incumbent may provide technical guidance, training, and work direction to junior scientists, research associates, consultants, CDMOs, CTLs, and other external partners
WORKING CONDITIONS:
Environment: primarily working in laboratories or in office
Exposures encountered, such as hazardous materials, and extreme cold.
Limited travel requirement
#LI-MB1
Our compensation reflects the cost of labor across several U.S. geographic markets, and we pay differently based on those defined markets. The base pay range for this position is $127,500 - $180,500 annually. The base pay range may take into account the candidate’s geographic region, which will adjust the pay depending on the specific work location. The base pay offered will take into account the candidate’s geographic region, job-related knowledge, skills, experience and internal equity, among other factors.In addition to the base salary, as part of our Total Rewards program, Exelixis offers comprehensive employee benefits package, including a 401k plan with generous company contributions, group medical, dental and vision coverage, life and disability insurance, and flexible spending accounts. Employees are also eligible for a discretionary annual bonus program, or if field sales staff, a sales-based incentive plan. Exelixis also offers employees the opportunity to purchase company stock, and receive long-term incentives, 15 accrued vacation days in their first year, 17 paid holidays including a company-wide winter shutdown in December, and up to 10 sick days throughout the calendar year.If you have a disability and need an accommodation in relation to the recruiting process, please email us at: [email protected].
WORKING CONDITIONS:
Our office is a modern space that fosters collaboration and creativity. Teams work closely together, sharing ideas and solutions in a supportive atmosphere. We provide all necessary equipment, including dual monitors and ergonomic chairs, to ensure a comfortable workspace.
DISCLAIMER:
The preceding job description has been designed to indicate the general nature and level of work performed by employees within this classification. It is not designed to contain or be interpreted as a comprehensive inventory of all duties, responsibilities and qualifications required of employees assigned to the job.
We are an Equal Opportunity Employer and do not discriminate against any employee or applicant for employment because of race, color, sex, age, national origin, religion, sexual orientation, gender identity, status as a veteran, and basis of disability or any other federal, state or local protected class.
Skills Required
- Ph.D. in chemistry, biochemistry, analytical chemistry, pharmaceutical sciences, chemical engineering, protein chemistry, or a related field with relevant industry experience
- Alternatively, a master's degree in a related field with 5 or more years of relevant industry experience
- Alternatively, a bachelor's degree in a related field with 7 or more years of relevant industry experience
- Equivalent combination of education and experience
- Hands-on experience in protein characterization and structural elucidation using high-resolution mass spectrometry, including Orbitrap or Q-TOF
- Technical experience with LC-MS/MS workflows for intact protein, reduced/subunit, peptide mapping, PTM, disulfide mapping, glycan/glycopeptide, sequence confirmation, and chromatographic peak identification
- Experience developing analytical assays for ADCs, including SEC, HIC, RP-HPLC, icIEF, CE-SDS, DAR-related analysis, and residual-free drug analysis
- Experience with higher-order structure analysis, including SEC-MALS, DSC, FTIR, or CD
- In-depth knowledge of biologics analytical development, protein chemistry, mass spectrometry, chromatography, electrophoresis, and CMC product characterization
- Understanding of critical quality attributes for biologics and ADCs
- Ability to design scientifically sound studies, interpret complex analytical data, and translate findings into CMC decisions
- Strong technical writing skills for protocols, reports, SOPs, regulatory sections, and investigation summaries
- Ability to collaborate with cross-functional teams and external CDMOs or CTLs
- Excellent communication, presentation, collaboration, and problem-solving skills
- Ability to prioritize multiple programs and deliver high-quality work in a fast-paced environment
Exelixis Compensation & Benefits Highlights
The following summarizes recurring compensation and benefits themes identified from responses generated by popular LLMs to common candidate questions about Exelixis and has not been reviewed or approved by Exelixis.
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Retirement Support — Retirement plans are highlighted as a strength, featuring a 401(k) with generous company contributions and immediate vesting. This emphasis signals strong long‑term financial support within the total rewards package.
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Healthcare Strength — Healthcare coverage is positioned as comprehensive, with multiple medical plan options (HDHP with HSA, EPO, and Kaiser HMO in CA) and employer HSA contributions in 2026. Posted plan documents and contribution details indicate structured support for managing care and costs.
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Parental & Family Support — Family support is robust, including fully paid parental leave, caregiver leave, and expanded fertility benefits. Additional elements such as grandparent leave and backup care broaden assistance across life stages.
Exelixis Insights
What We Do
Every Exelixis employee is united in an ambitious cause: to launch innovative medicines that give patients and their families hope for the future. In this pursuit, we know our employees are our most valuable asset. After operating in the challenging biotech sector for more than 25 years, we have a proven track record of resiliency in the face of adversity. The success of our lead product has provided a solid commercial foundation allowing us to reinvigorate our research efforts, and grow our team in areas such as Drug Discovery, Clinical Development and Commercial. As we expand our global partnerships and further reinvest in R&D to help us discover the next breakthrough for difficult-to-treat cancers, we’re seeking to add talented, dedicated employees to power our mission. Cancer is our cause. Make it yours, too. Please see our Community Guidelines: bit.ly/2XXw9w3 For more information about Exelixis, please visit www.exelixis.com, follow @ExelixisInc on Twitter or like Exelixis, Inc. on Facebook.








