Senior Research Associate, In Vivo Biology

Cambridge$81k–$107kPosted Jul 29, 2026

Position Summary:

Prologue Medicines are seeking a highly motivated and detail-oriented Senior RA to join our dynamic In Vivo Biology team, leading projects in discovery and pre-clinical development for therapeutic proteins of viral origin. The successful candidate will play a key role in designing, executing, and analyzing in vivo studies to evaluate therapeutic proteins with the aim of nominating development candidates, and supporting preclinical development and translational science of these molecules through to IND and beyond.

As a member of our team, you will be responsible for designing and executing experiments to understand the activity, mechanism of action, and therapeutic potential of early-stage biologics in vivo. This role offers the opportunity to work in a dynamic, fast-paced, entrepreneurial environment, working independently as well as collaboratively within a highly integrated team. This is an on-site role in Somerville, MA.

Key Responsibilities:

Planning, execution, and analysis of in vivo experiments to evaluate the therapeutic potential of our test articles including pharmacokinetic/pharmacodynamic, biodistribution, and efficacy studies.
Conducting ex vivo wet lab experiments to analyze PD phenotypes and MoA in different tissues.
Ability to work independently and as part of a collaborative team to design, plan and execute experiments, and manage outcomes to support research activities, project goals, and platform development.
Creative and strategic contributions to the discussions, designs, and implementation of in vivo and ex vivo
Managing relationships with external research facilities.
Reporting results to the scientific team and management.
Critical data analysis, attention to detail, and troubleshooting abilities.
Maintaining an organized and up-to-date electronic lab notebook.
Writing, updating, and maintain high-quality experimental protocols.

Basic Requirements:

Bachelor’s or MS degree with 3+ years of relevant experience with in vivo and ex vivo lab experiments in accademia or industry.

Extensive experience with mouse handling: injections (IV, IM, IP), blood collection, and tissue harvesting is essential.
Performing and recording animal health observations, communicating adverse findings to the veterinarian technicians to ensure animal care standards are in keeping with applicable laws and regulatory guidelines.
Writes and maintains animal protocols.
Experienced with various ELN and LIMS systems.
Excellent communication and presentation skills, capable of conveying technical information in a clear and thorough manner, document results in laboratory notebooks.
Demonstrated ability to work in a highly collaborative team environment.
Motivated and excited about biological discovery and assay development.
A dynamic problem solver and self-starter

Preferred Requirements:

Hands on experience in a variety of ex vivo/in vitro analysis techniques such as ELISA, MSD, Luminex, ELISpot, and flow cytometry from a wide range of different tissue types.
A proven track record of developing and optimizing disease efficacy models in mice.

Flagship Pioneering and our ecosystem companies are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity or Veteran status.

At Flagship, we recognize there is no perfect candidate. If you have some of the experience listed above but not all, please apply anyway. Experience comes in many forms, skills are transferable, and passion goes a long way. We are dedicated to building diverse and inclusive teams and look forward to learning more about your unique background.

Recruitment & Staffing Agencies: Flagship Pioneering and its affiliated Flagship Lab companies (collectively, “FSP”) do not accept unsolicited resumes from any source other than candidates. The submission of unsolicited resumes by recruitment or staffing agencies to FSP or its employees is strictly prohibited unless contacted directly by Flagship Pioneering’s internal Talent Acquisition team. Any resume submitted by an agency in the absence of a signed agreement will automatically become the property of FSP, and FSP will not owe any referral or other fees with respect thereto.

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The salary range for this role is $81,000 - $107,250. Compensation for the role will depend on a number of factors, including a candidate’s qualifications, skills, competencies, and experience. Prologue Medicines, Inc. currently offers healthcare coverage, annual incentive program, retirement benefits and a broad range of other benefits. Compensation and benefits information is based on Prologue Medicines, Inc.'s good faith estimate as of the date of publication and may be modified in the future.