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Research Associate - Assay and Screening

Assay and Screening | South San Francisco, CA | Full Time

Job Description

Research Associate - Assay and Screening

Plexxikon, a member of the Daiichi Sankyo group, is a leader in the discovery and development of novel, small molecule pharmaceuticals. The company utilizes its proprietary discovery platform to successfully develop a portfolio of competitively differentiated clinical and preclinical stage compounds in a number of therapeutic areas. Our most advanced program, Zelboraf™ (vemurafenib) was the first precision medicine to be approved for the treatment of BRAF-mutant metastatic melanoma. Turalio™ (pexidartinib), Plexxikon’s second FDA-approved drug, is the first and only approved therapy for tenosynovial giant cell tumor. Plexxikon's novel discovery approach, experienced management and scientific teams, and broad network of scientific and development partners, have been key drivers of the company's success since operations began in 2001. Plexxikon is a small business with approximately 70 employees based in South San Francisco, CA

The Assay and Screening group supports projects at all stages of the pipeline as part of an integrated and cross-functional drug discovery team. In addition to developing and executing biochemical and cell-based screens, Assay and Screening group members also conduct studies for validation of novel targets and mechanism of action of lead compounds. The Research Associate will report to and work under the guidance of a Scientist in the Assay and Screening team. This is a unique opportunity to become a key contributor to drug discovery in a successful biotechnology company.  


  • Conduct compound screens using various biochemical and cell-based assays
  • Maintain cell lines for internal and external studies
  • Database entry and analysis, and quality control of compound activity data
  • Provide compound activity reports to interdisciplinary project teams
  • Assist in target validation and biochemical/cellular characterization of hits or leads
  • Document work in electronic laboratory notebook, with quality suitable for publication and patent protection
  • Maintain various lab equipment and a clean, safe lab environment
  • Present progress at Assay and Screening group and cross-functional team meetings
  • Other duties as assigned


  • BS/MS degree in life science or related field, title commensurate with experience
  • Understanding of scientific concepts in assay development and interest in the drug discovery process
  • Experience with standard laboratory instrumentation, detection techniques, and cell culture is highly desired
  • Experience with western blotting, stable cell line development, and genetic approaches for interrogating protein function (eg. siRNA, shRNA, or CRISPR) a plus
  • High attention to detail and accuracy
  • Excellent interpersonal, verbal, and written communication skills
  • Team-oriented, highly motivated, and adaptable to changing priorities in a fast-paced environment


We offer a chance to work with talented people in a collaborative environment and provide top-notch benefits including health insurance, generous time off, annual performance bonuses, and long-term incentives. As an equal opportunity employer, Plexxikon is committed to a diverse workforce. Employment decisions regarding recruitment and selection will be made without discrimination based on race, color, religion, national origin, gender, age, sexual orientation, physical or mental disability, genetic information or characteristic, gender identity and expression, veteran status, or other non-job-related characteristics or other prohibited grounds specified in applicable