Careers
Raven StealthCo - Principal Scientist, In Vivo Pharmacology
Boston, MA, USA
USD 170k-185k / year
Posted on Sep 1, 2026
About Raven:
We are Raven, RA Capital’s healthcare incubator. From discovery to delivery, whether we incubate, accelerate or rejuvenate, Raven’s goal is to turn scientific breakthroughs into transformative therapies and get them quickly, safely and efficiently to the patients that need them most. Raven’s experienced scientists, operators, and healthcare innovators have deep sector expertise across therapeutics, diagnostics, devices and services. They have brought hundreds of therapeutics into development, managed hospital systems, optimized clinical trials and navigated payor and regulatory systems to deliver patient impact - and they are ready to work with you.
About RA Capital:
Founded in 2004, RA Capital Management is a multi-stage investment manager dedicated to evidence-based investing in public and private healthcare, life sciences, and planetary health companies. RA Capital creates and funds innovative companies, from private seed rounds to public follow-on financings, allowing management teams to drive value creation from inception through commercialization and beyond. RA Capital's knowledge engine is guided by our TechAtlas internal research division, and Raven, RA Capital’s company building team, offers entrepreneurs and innovators a collaborative and comprehensive platform to explore the novel and the re-imagined. RA Capital has more than 150 employees and over $10 billion in assets under management.
Company Background
We are a well-funded, stealth-mode biotechnology focused on next generation oligo-based modalities targeting tissues beyond the liver, muscle, and kidney. We are building a platform to deliver oligos with high precision to previously untargeted cells, while focused on “undruggable” genes, alone or in combination with previously validated targets. Many of our targets carry "pipeline-in-a-drug" potential: a single gene or protein with meaningful biological effects across multiple disease areas. Headquartered in Cambridge, Massachusetts, the company was incubated in RA Capital’s venture group (Raven) and is led by an experienced CEO. After a robust incubation and vetting process, Raven StealthCo was launched and funded by RA Capital. The company’s therapeutic areas of interest lie outside commonly targeted cells and tissues, and represent multi-billion-dollar markets that are continuing to grow as the population ages. Our initial focus is creating transformational therapies to treat diseases, but given the platform potential, we have longer-term ambitions to address healthy aging. These targets are backed by strong biological and genetic evidence but have historically resisted small molecule and biologic approaches. Raven StealthCo is moving quickly to address multiple disease indications at scale and with significant market potential.
Opportunity
We are in the discovery stage and will invest heavily in our emerging platform for oligonucleotide delivery. Our disease focus is supported by highly predictive animal models with strong translatability to humans, offering a potentially rapid and efficient path to the clinic. Given our recent funding and commitment to building a first-in-class platform, we are recruiting a Principal Scientist / Associate Director, In Vivo Pharmacology to design, manage, and interpret the externally executed studies that establish pharmacokinetics, target engagement, pharmacodynamics, and efficacy for our programs.
The Position
The Principal Scientist reports to the Director of Biology and Pharmacology and leads the company’s in vivo pharmacology efforts, owning how studies are designed, run, and analyzed. Working in close partnership with the Director, who sets the overall biology and pharmacology strategy in accordance with the company goals and broad scientific strategy, this person translates that strategy into a rigorous in vivo program and drives it end to end.
In vivo studies will be run externally at contract research organizations while the ex vivo analyses will be executed both internally and externally. The Principal Scientist’s focus will be the design, direction, and interpretation of that work rather than its hands-on execution. The successful candidate will be point of contact for day to day management including study design, CRO scoping and oversight, sample logistics, tissue-processing support, and data interpretation. This will be an individual contributor role at hire, with clear room to expand in scope and influence as the portfolio and team grow.
Specific responsibilities include:
- Partner with the Director to set the staged in vivo pharmacology plan (target validation and proof-of-concept through dose-response, duration of effect, and candidate selection and development), and own its execution
- Design the CRO-executed rodent and non-human-primate studies (controls, power, pre-specified endpoints) and author the protocols and analysis plans
- Qualify and manage CRO partners for in vivo studies and outsourced analytics (scope, budget, timeline, quality), serving as day-to-day scientific contact from pre-study alignment through in-life monitoring and troubleshooting
- Select, qualify, and de-risk the in vivo models, setting performance, variability, and effect-size expectations before pivotal studies
- Own the in vivo endpoint suite: quantitative histology and morphometry, tissue-based PD readouts, circulating and tissue biomarkers, and -omics readouts as needed
- With the delivery and analytical chemistry groups, connect biodistribution and tissue exposure to pharmacodynamics and phenotype, and design and interpret the PK/PD studies that set exposure–activity–efficacy relationships for dose, schedule, and duration
- Define the in vivo and translational biomarker plan carrying programs from research into development, aligned with overall program strategy
- Own sample logistics for in vivo studies (receipt, cataloging, storage, chain of custody, and shipment to and from CRO and analytical partners), specifying per study which tissues and readouts are needed and handing samples to the in vitro scientist for execution
- Provide hands-on support for tissue processing so samples reach downstream analysis fit for purpose
- Benchmark candidates against standard-of-care and mechanistic comparators, and contribute to IND-enabling and larger-species study design and the nonclinical narrative as programs mature
- Provide sponsor-side data integrity, documentation, and animal-welfare oversight of external studies (CRO and IACUC review, chain of custody, reproducibility) for an eventual regulatory package, and build the in vivo record-keeping, data, and protocol templates the group runs on
- Mentor junior team members and help grow the team as remits expand
- Bring in vivo results, their program implications, and competitive-landscape intelligence into cross-functional and leadership discussion, help shape how in vivo findings reach the Board, investors, and partners, and contribute to publications, patents, and presentations
The Individual
The Principal Scientist can design a study, direct its execution through a third party, and defend its interpretation. Because our in vivo work is externalized, they must anticipate where a model will fail, recognize when data quality has drifted, and know which questions to ask before a study, not after, with the judgment to separate a real pharmacologic effect from an artifact of model, timing, or analysis.
Equally important is ownership: someone who treats the in vivo package as theirs to deliver, anticipating needs, raising concerns early, and following issues to resolution unprompted. They bring independent, well-reasoned thinking to the in vivo strategy and partner closely with the Director to shape it, going deep as the in vivo pharmacology expert the rest of the team relies on. Experience mentoring juniors is welcome; the appetite to build rigorous in vivo practice from the ground up matters more than a long management record.
Key qualifications include:
- PhD. in pharmacology, physiology, cell and molecular biology, or a related discipline, with 7+ years of relevant biopharmaceutical industry experience; or M.S./B.S. with commensurate experience. Title will be commensurate with level of qualifications and experience
- Demonstrated ownership of in vivo pharmacology workstreams in discovery research and preclinical development, from target validation through candidate selection and development, with learning agility across disease biology
- Track record designing, outsourcing, and managing CRO-executed in vivo studies: vendor qualification, protocol negotiation, budget and timeline ownership, on-site oversight (if needed), and critical evaluation of external data
- Hands-on rodent experience (dosing by multiple routes, in-life assessment, terminal collection) sufficient to design realistic protocols and challenge a CRO, plus experience designing or running non-human-primate studies
- In vivo phenotyping experience (quantitative imaging, histology and morphometry, tissue functional testing, circulating biomarkers); experience in our indication is a plus, not a requirement
- Experience developing translational biomarkers across research and development is a plus, as is experience with oligonucleotide therapeutics or other genetic medicines, especially interpreting pharmacology where exposure, target engagement, and phenotype are separated in time
- Strong quantitative and statistical fluency; comfort with R or Python for larger datasets is a plus
- Working familiarity with IACUC review, AAALAC-accredited facilities, and the documentation behind a defensible nonclinical package, sufficient for sponsor-side oversight of external studies
- Comfortable guiding junior scientists day to day, or eager to grow into it
- Brings a strategic, program-level perspective to in vivo pharmacology and is motivated to expand that influence as the company grows
- Process- and detail-oriented, and an effective communicator who operates independently and manages external partners with authority, keeping in vivo data reproducible, well-controlled, and decision-grade
At a personal level, we want someone collaborative, collegial, intellectually curious, driven, trustworthy, and humble, with sound judgement and strong technical decision-making. As one of our earliest and more senior hires, this person helps shape a culture we are deliberate about: rooted in psychological safety, where good ideas are welcomed from any seat, respect is paramount, failure is a chance to learn rather than a cause for blame, and mentorship is the spine of strong teams. In a role this senior, they set the standard for how we mentor and develop scientists as the team grows. Underlying all of it is a commitment to rigorous science and to the patients waiting for treatments that meet their needs, which is why we move with urgency. The team is small, the work deeply cross-functional, and priorities shift, so we want someone thoughtful, highly organized, and energized by a fast-paced start-up, with significant latitude to shape how we run in vivo pharmacology and a clear path to grow in scope and leadership as the organization matures.
From an educational perspective, we are seeking an individual with a degree in a relevant discipline such as pharmacology, physiology, or cell and molecular biology. It is understood that education, while an important index of achievement, orientation, and intellectual capacity, will not constitute the primary variable in this decision process. Personal characteristics, leadership abilities, technical fluency, creativity, work ethic, behavioral flexibility, and demonstrated accomplishments will serve as key components in the evaluation of candidates. This person will be based at the company’s headquarters in Cambridge, MA, on a hybrid schedule.
The base salary range reflects our good faith estimate at the time of posting. Final compensation will depend on factors like experience, skills, and location. The role may also be eligible for an annual bonus and long-term incentives. Compensation and benefits may be updated in the future.
Salary base range
$170,000—$185,000 USD