Scientist/Sr. Scientist, Preclinical Bioassay Development

South San Francisco, CA
Jul 23, 2021
Required Education
Position Type
Full time

About Mantra Bio:

At Mantra Bio, we seek to eliminate disease-related suffering to enhance the well-being of all. We believe that the key to creating cures is targeted, tissue-specific delivery of therapeutics for dramatically increased efficacy and reduced toxicity. To achieve this, our team of biologists, data scientists, and platform engineers have created REVEALTM, a targeted cargo delivery platform that harnesses exosomes, the body's natural cellular transport system, to create  highly tunable exosome therapeutics for some of the most devastating  diseases. The foundation of our success is our truly interdisciplinary team of experts who work collaboratively to use the power of data science to fuel and accelerate our wet-lab successes. As a team, we value Self-Empowerment, Candor, Curiosity, and Collaboration and consider our human-centric culture to be our most important asset. We are proud to count 8VC, Viking, Illumina, Allen & Company and TenCent among our investors. Mantra Bio operates out of a newly constructed facility in South San Francisco.

About the Role:

Mantra Bio is seeking a highly motivated Scientist to perform bioanalytical and immune assay development and preclinical sample analysis, in support of existing therapeutic candidates and other early discovery efforts. As part of our preclinical team, you will work cross-functionally with scientists, engineers, and data scientists to develop critical assays. As a successful applicant, you are operationally minded, able to drive multiple projects in parallel, while communicating strategy, methodology, and progress updates. You will have prior hands-on experience developing bioanalytical and immune assays, along with animal handling (primarily rodents) for preclinical studies. You are comfortable working independently, mentoring junior staff, working collaboratively across various projects to meet milestones, and playing a key role in building the culture of a growing company.


  • Development and execution of bioanalytical and immune assays in vitro and ex vivo for new candidates selection to generate SOPs and support the preclinical activities.
  • Perform ex vivo and in vitro analyses to examine drug pharmacodynamics and support biomarker discovery.
  • Independently design, develop and execute cell based assays, using primary and cell line cultures to examine target binding and downstream pathway modulation for different candidates to meet strict timelines.
  • Assist the in vivo team as needed with sample collection and processing.
  • Complete accurate documentation of all work performed in a database and electronic lab notebook (ELN).
  • Work very closely with scientists from other teams at Mantra to coordinate tasks and ensure that projects milestones are completed.
  • Analyze and process data to generate presentations for internal and external company meetings, supporting company leadership in patent filing and scientific publications.
  • Work closely with Senior Director of Preclinical Development to communicate strategy, methodology, progress and challenges to drive the team and projects forward.
  • Provide training, guidance and mentorship to junior staff on the preclinical team.

What We're Looking For:

  • Ph.D. in immunology, pharmacology, biomedical engineering or similar with >3 years, or MS with 5-7 years or BS with 7-10 years of relevant experience of drug development in an industry or academic setting. 
  • Extensive hands-on experience with translation assays, developing and validating bioanalytical and immune assays, using animal samples with various methods, such as multicolor flow cytometry, tissue histology, cytokine analysis panel, ELISA, neutralization assays, ELISPOT, western blotting, RT-qPCR, confocal microscopy and enzymatic activity assays to support the preclinical activities.
  • Experience with various in vitro assay and techniques using primary and cell line cultures.
  • High level of expertise to troubleshooting complex technical problems and finding appropriate solutions.
  • Small molecule knowledge and hands-on experience with metabolic assays using HPLC is a plus.
  • Hands-on experience with animal (rodent) handling, including but not limited to drug administration (IV, IP, and IM injection), anesthesia, organ harvest and in vivo imaging is nice to have.
  • Excellent organizational and documentation skills with prior experience writing bioassay development reports in a GLP-like environment is highly desirable.
  • Ability to work independently, with minimal supervision, highly self-motivated and detail-oriented individual, with proven ability to work in a dynamic and fast paced environment in a small startup company.
  • Experience mentoring, coaching, and training junior staff members is preferred.
  • Familiarity or experience with scripting and statistical analysis of data is nice to have.
  • Comfortable or with experience collaborating with data-driven computational scientists and platform engineers from different backgrounds, while analyzing data is nice to have.

Mantra Bio’s Culture:

At Mantra Bio, we value Self-Empowerment, Candor, Curiosity, and Collaboration. We take pride in being a  human centric, collaborative work place that brings  wildly intelligent and business savvy Top Talents  together to build the next revolution in targeted drug delivery. We believe that a great team makes a successful company and we trust each team member to do what’s best for the organization. We believe that a culture of feedback in an environment of empathy and respect is essential to cultivating curiosity and learning, leading to personal growth and the growth of our organization. Most importantly, we love handing out Kudos, being creative and celebrating our success together. We are committed to creating a diverse and inclusive environment and we are proud to be an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status.


  • Comprehensive health benefits package
  • 401k
  • Meaningful stock option grants
  • Flexible PTO and year-end shutdown
  • Generous Parental Leave program
  • Growth-oriented professional development opportunities
  • Team-building events
  • Fully stocked kitchen