Raven StealthCo - Associate Scientist, In Vitro Pharmacology and Assay Development

Raven StealthCo - Associate Scientist, In Vitro Pharmacology and Assay Development 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 thepopulation ages. Our initial focus is creating transformational therapies to treatdiseases, but given the platform potential, we have longer‑term ambitions to address‑healthy aging. These targets are backed by strong biological and genetic evidence buthave historically resisted small molecule and biologic approaches. Raven StealthCo ismoving quickly to address multiple disease indications at scale and with significantmarket potential. We are in the discovery stage and will invest heavily in our emerging platform for oligonucleotide delivery. Our disease focus offers strong translatability from animal models to humans, which provides 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 Associate Scientist In Vitro Pharmacology and Assay Development to help build and run the in vitro pharmacology engine (target ID and pathway validation, oligonucleotide profiling, and mechanism-of-action work) and to execute the ex vivo analyses that turn our externalized in vivo studies into interpretable results. The Associate Scientist reports to the Director of Biology and Pharmacology and works closely with delivery, conjugation chemistry, and analytical colleagues. This lab-based role spans two capabilities the company cannot advance without: a rigorous in vitro pharmacology engine (physiologically relevant primary and stem-cell-derived models, oligonucleotide screening, mechanism-of-action work), and hands‑on support of our externalized in vivo pharmacology, executing the ex vivo analyses on samples returning from CRO-run studies in partnership with the in vivo pharmacology lead. The two are connected by deep molecular biology, biochemistry, and -omics fluency, and as programs move toward development, translational biomarker work grows more central. As a founding member of the scientific team, this person helps build the lab and define how our core assays run. First-year priorities are clear: stand up cell culture, bring the CRO-run cell-based screening in-house, and establish the tissue-processing and ex vivo readouts our programs depend on. Specific responsibilities include: Stand up the company’s cell culture from the ground up: primary and stem-cell-derived cells, directed differentiation, and readouts of maturation and functional states Design, develop, and run reproducible in vitro assays for oligonucleotides and conjugates, quantifying target engagement and PD effect across delivery formats (RT-qPCR, digital PCR, branched-DNA, immunoassays) and characterizing dose–response for conjugate optimization Build an assay toolkit for deeper hit profiling, including uptake, internalization, and trafficking assays for conjugate-mediated delivery Establish tissue-processing techniques and the ex vivo PD and efficacy analyses supporting in vivo studies (including RNA and protein extraction from difficult tissues); run the readouts on returning CRO samples and contribute to the ex vivo analytical plan up front With analytical chemistry, who lead bioanalytical method development for oligonucleotide and conjugate quantitation, deliver the tissue-exposure and biodistribution data anchoring PK/PD interpretation In line with the team’s biomarker strategy, develop and implement assays for translational biomarkers that track PD effect, target engagement, and early efficacy into development Bring in new methods, technologies, and vendors where existing approaches fall short, and operationalize methods once established: robust, documented, transferable assays with defined controls, acceptance criteria, and performance tracking Help build the lab (procurement, installation, equipment qualification), train future team members, and build and maintain the templates and records the organization runs on (data management, inventory, SOPs, assay protocols, and electronic lab notebook) Work hand-in-hand with the Director, the in vivo pharmacology lead, delivery scientists, and chemists to keep in vitro and ex vivo readouts timely and well-controlled, and contribute ideas and interpretation to broader scientific discussion The Individual The Associate Scientist is a self‑starter who generates high-quality, reproducible biological data and helps interpret it, with direct hands‑on expertise in mammalian cell culture and molecular biology in a discovery setting and real attention to detail. It is a technically advanced role: we expect deep independence in execution, paired with eagerness to grow the scientific and strategic judgment that turns good data into good decisions. We want someone drawn to establishing new methods, comfortable with the ambiguity of building something for the first time, and uncompromising about rigor, someone who believes a method is not finished until it is operationalized: documented, controlled, reproduced, and trustworthy when a program decision rests on it. Builder acumen matters, as does setting the assay, data, and quality standards a young organization will run on for years. The work is deeply collaborative, so we want someone collegial, adaptable as priorities shift, and glad to take as much satisfaction in the team’s success as their own. BS with 8+ years or MS with 6+ years of relevant experience, preferably in biotech settings. Title will be commensurate with depth of qualifications and experience Hands‑on aseptic technique and mammalian cell culture (immortalized and primary lines) and end‑to‑end cell-based assay development (conception, optimization, troubleshooting, routine execution); experience with differentiation or stem‑cell‑derived systems strongly preferred Strong molecular biology and biochemistry: RNA and protein isolation from cells and tissues and quantitative gene‑and protein‑expression analysis (RT-qPCR, ddPCR, MSD/ELISA, Protein Simple, flow cytometry) Experience with oligonucleotide modalities and a range of delivery systems (transfection, free uptake, LNP, and/or conjugate), and supporting in vivo pharmacology through target‑engagement, pharmacodynamic, and translational biomarkers Fluency accessing and synthesizing -omics datasets (RNA-seq, spatial transcriptomics, metabolomics, proteomics), with enough grounding in the methods to scrutinize and interpret the data Some familiarity with histology and in situ tissue analysis (sectioning, immunohistochemistry, in situ hybridization, microscopy, quantitative image analysis), and some coding for larger‑dataset analysis (R or Python), are pluses A track record of establishing a method, assay, or capability that did not previously exist in a lab, including the documentation and training that made it reliable for others Initiative and independent scientific thinking: identifying a problem, proposing an approach, and carrying it through with limited supervision Process‑and detail‑oriented, with the creativity to build novel assays while keeping data decision‑grade, and an effective communicator who operates independently in the lab 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 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 accessible mentorship is the spine of strong teams. Underlying all of it is a commitment to rigorous science and to the patients waiting for treatments that better 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 real influence on the science and room to grow as the company advances. 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 dictated by wet‑lab experimental needs. 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

$100,000 - $120,000 USD