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Sr. Scientist / Scientist, Analytical Development

Company Overview:

Janux Therapeutics is a biotechnology company based in San Diego that is leveraging an innovative and proprietary discovery platform to efficiently develop tumor activated therapeutics that attack and kill cancer. These protein biologics empower the immune system to fight cancer without destroying the patient’s healthy tissues. Janux is looking for an energetic and talented candidate with a desire to work in a rapidly growing, fast-paced, and dynamic cross functional team environment. We believe that the whole team contributes to the overall mission. We succeed as a team, and we grow as a team!

Sr Scientist/ Scientist, Analytical Development

We are seeking a Sr Scientist/ Scientist with demonstrated research skills who can lead the development and implementation of state-of-the-art quantitative and qualitative bioanalytical methods to support discovery and pre-clinical development of lead candidates. As a key member of the bioanalytical development team, they will provide scientific and technical expertise in efforts to develop and execute bioanalytical assays in support of CMC and R&D efforts. The successful candidate will have extensive hands-on experience with assay development including LC-MS/MS, RP-HPLC, SEC, IEX, cIEF, ELISA. The Sr Scientist/Scientist will be responsible for supporting CMC efforts and working with CDMOs as well as supporting internal research efforts related to pre-clinical drug discovery and characterization.

This position is hands-on and requires effective communication and documentation of results that enable the advancement of novel research molecules toward development and clinical candidates and ultimately into late-stage development and commercial. Ideal applicants will be highly driven, collaborative and team-oriented, possess excellent communication and organizational skills, and carry a strong commitment to excellence.

Education and Experience Requirement:

  • PhD and 5+ years of industry experience or highly proficient MS with 8+ years’ experience in bioanalytical chemistry or a related field.
  • Current knowledge with the characterization of mammalian-derived biologics and/or bispecifics is preferred.
  • Proven expertise and experience in LC-MS and MS/MS including intact mass, peptide mass mapping, immunocapture, digestion and MRM based quantitation of proteins.
  • Previous experience in mass spectrometry applications in ADC/protein biologics analytics, metabolomics and proteomics would be advantageous. 
  • Scientific curiosity and strong capabilities in experimental design, execution, data interpretation and troubleshooting with limited supervision.
  • Ability to think critically and to prioritize and manage multiple projects in a fast-paced environment.
  • Proven track record of success in anticipating and managing issues in a proactive fashion.

Role Responsibilities

  • Design, conduct, analyze, interpret, and report laboratory experiments both internally and at external CDMOs
  • Develop, validated and troubleshoot new bioanalytical methods including LC-MS and LC-MS/MS, HPLC e.g., IEX, SEC, RP purity and capillary-based nano-immunoassays
  • Support stability, formulation and in-use studies with assay development; generate key data sets to accelerate programs.
  • Develop and execute standard operating procedures within the Janux programs, supervise assay transfer to our partners and contract labs
  • Help manage internal laboratory activities under tight timelines
  • Supervise, train and mentor junior staff and provide insight and technical expertise for project progression
  • Conduct multiple research activities in parallel
  • Support identification and prioritization of high-impact research activities
  • Keep up with published literature centered around bioanalytical characterization of protein biologics relevant to Janux programs

Required Key Attributes:

  • Excellent oral and written communication skills
  • Candidate must have effective troubleshooting and problem-solving skills
  • Success in this role requires great attention to detail with the ability to multitask
  • Candidate must be an effective team player, strong individual contributor, self-motivated, flexible, and able to handle multiple tasks and deliver high-quality results under tight timelines
  • Highly organized and diligent about documentation is required and cannot be overstated
  • Some travel domestic and international (when permitted) may be required (<10%)

Does this sound like you? Apply now to take your first steps toward contributing to the development of next generation protein therapeutics to eliminate cancer.


  • 401K
  • Medical insurance
  • Dental insurance
  • Vision insurance
  • Supplemental disability insurance plans
  • Flexible schedule
  • Life insurance
  • Flexible vacation
  • Incentive stock option plan
  • Employee stock purchase plan


Monday to Friday On-Site (La Jolla, CA)

Work authorization:

United States (Required)

COVID-19 Vaccination required

Janux requires all new hires to be fully vaccinated for COVID-19 prior to the first date of employment.  As required by applicable law, Janux will consider requests for Reasonable Accommodations.


Janux Therapeutics, Inc. is an equal opportunity employer that is committed to providing a work environment free of harassment and discrimination based upon a protected category, as well as an environment free from retaliation for protected activity.