Principal Scientist Jobs in San Francisco, CA

INTRODUCTION

We are seeking a highly motivated and innovative Associate Principal Scientist to join our Discovery Oncology team in South San Francisco. The successful candidate will have a strong track record in oncology and drug discovery and will lead the conception, design, and execution of discovery-stage research programs. In this role, you will partner closely with cross-functional teams across the organization to advance differentiated cancer therapies from target validation through early development.

Key Responsibilities:

• Design, establish, and optimize in vitro and ex vivo assays to elucidate mechanisms of action and assess therapeutic potential.
• Make timely, data-driven decisions that balance innovation, risk, and experimental rigor.
• Communicate scientific strategy, rationale, and results clearly to internal teams and help build external scientific presence through publications, conference presentations, and collaboration.
• Drive ideation and early-stage discovery efforts to deliver competitive oncology programs, leveraging internal expertise and emerging technologies.

QUALIFICATIONS:

Education:

• Ph.D. in Cancer Biology, Cell Biology, Pharmacology, Immunology, Biochemistry, or a related discipline with four (4) or more years of relevant oncology drug discovery experience.

Required Experience and Skills:

• Deep expertise in tumor biology and immune oncology, including cancer genomics and oncogenic signaling.
• Broad technical expertise in molecular and cellular biology, biochemistry, and analytical methods.
• Extensive hands-on in vitro experience designing, executing, and analyzing multi-color flow cytometry and mechanistic cell-based assays (e.g., viability/cytotoxicity, cell cycle, signaling, and immune response readouts).
• Demonstrated ability to drive innovative research, evidenced by high-impact publications, patents, and/or successful advancement of discovery programs.
• Passionate, creative, and collaborative scientist committed to improving outcomes for people living with cancer.
• Excellent oral and written communication skills, a positive, team-oriented mindset, and strong leadership potential.

Preferred Experience and Skills:

• Hands-on experience with different therapeutic modalities (e.g., small molecules, mAbs, ADCs and TCEs).
• Extensive hands-on experience designing, executing, and analyzing in vivo mouse model data to evaluate therapeutics.

Required Skills:

Biochemistry, Cancer Cell Biology, Cancer Research, Cell Biology, Immuno-Oncology, In Vitro Biology, In Vitro Research, In Vitro Studies, Molecular Biology, Oncology, Tumor Biology.

US and Puerto Rico Residents Only:

Our company is committed to inclusion, ensuring that candidates can engage in a hiring process that exhibits their true capabilities. Please click here if you need an accommodation during the application or hiring process.

As an Equal Employment Opportunity Employer, we provide equal opportunities to all employees and applicants for employment and prohibit discrimination on the basis of race, color, age, religion, sex, sexual orientation, gender identity, national origin, protected veteran status, disability status, or other applicable legally protected characteristics. As a federal contractor, we comply with all affirmative action requirements for protected veterans and individuals with disabilities. For more information about personal rights under the U.S. Equal Opportunity Employment laws, visit:

EEOC Know Your Rights
EEOC GINA Supplement

We are proud to be a company that embraces the value of bringing together talented and committed people with diverse experiences, perspectives, skills, and backgrounds. The fastest way to breakthrough innovation is when people with diverse ideas, broad experiences, backgrounds, and skills come together in an inclusive environment. We encourage our colleagues to respectfully challenge one another’s thinking and approach problems collectively.

Learn more about your rights, including under California, Colorado and other US State Acts.

COMPENSATION

• Salary Range: $159,600.00 - $251,200.00

This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. An employee’s position within the salary range will be based on several factors including, but not limited to relevant education, qualifications, certifications, experience, skills, geographic location, government requirements, and business or organizational needs.

The successful candidate will be eligible for annual bonus and long-term incentive, if applicable.

We offer a comprehensive package of benefits. Available benefits include medical, dental, vision healthcare and other insurance benefits (for employee and family), retirement benefits, including 401(k), paid holidays, vacation, and compassionate and sick days. More information about benefits is available at https://jobs.merck.com/us/en/compensation-and-benefits.

You can apply for this role through https://jobs.merck.com/us/en (or via the Workday Jobs Hub if you are a current employee). The application deadline for this position is stated on this posting.

San Francisco Residents Only: We will consider qualified applicants with arrest and conviction records for employment in compliance with the San Francisco Fair Chance Ordinance.

Los Angeles Residents Only: We will consider for employment all qualified applicants, including those with criminal histories, in a manner consistent with the requirements of applicable state and local laws, including the City of Los Angeles’ Fair Chance Initiative for Hiring Ordinance.

Employee Status:

Regular

Relocation:

Domestic/International

VISA Sponsorship:

Yes

Travel Requirements:

10%

Flexible Work Arrangements:

Not Applicable

Shift:

1st - Day

Valid Driving License:

No

Hazardous Material(s):

n/a

Job Posting End Date:

07/10/2026* A job posting is effective until 11:59:59PM on the day BEFORE the listed job posting end date. Please ensure you apply to a job posting no later than the day BEFORE the job posting end date.

Requisition ID: R399744