Principal Scientist, Toxicology & Pharmacology

What if cancer drugs could find the tumor – and go nowhere else? What if this meant you could get potent therapy directly to the tumor, sparing healthy cells? That’s the future we’re building at Shasqi, using Nobel Prize-winning science to unleash powerful therapies only where they’re needed. We’re a small, driven team encompassing broad backgrounds and experiences, united by a single mission: make cancer treatments more effective with minimal side effects. Our Operating Principles We move fast because speed matters to cancer patients. We aim to communicate openly and challenge ideas regardless of job title. We are bold, take risks, and push boundaries being led by science. We operate with humble confidence: meaning we can balance our sense of capability and conviction without ego, while being humble to seek advice and learn from our mistakes. If that fires you up, come build the future of cancer therapy with us! You’re the right fit for Shasqi if you.. Are mission driven and eager to do the best work of your career, developing novel therapies that will transform cancer treatment. Can balance scientific rigor with a fast-paced environment. Are comfortable with ambiguity and making decisions in the face of uncertainty. Operate with a strong sense of agency and invite feedback and advice. Can challenge convention and think of creative solutions that meet the needs of the company. Are a doer, hands-on, resourceful, and do not hesitate to step up. Willing to collaborate, debate, commit to decisions clearly, and revisit when evidence demands it. Position Overview We are seeking a strategic and hands-on Principal Scientist, Toxicology & Pharmacology to contribute to strategy and execution of nonclinical safety and pharmacology for our next-generation targeted therapy technology based on pre-targeting enabled by click chemistry. You will work together with chemistry, biology, and ADME/PK teams to design, lead, and interpret toxicology and pharmacology studies that contribute to therapeutic design, candidate selection, IND-enablement, and clinical strategy in a fast-paced startup environment. Key Responsibilities Nonclinical Safety Strategy Contribute to and execute toxicology strategy for pre-targeted therapeutics, including IND-enabling studies. Design GLP and non-GLP toxicology studies. Identify, characterize, and mitigate safety risks. Establish safety margins and therapeutic index for candidate molecules. Pharmacology & Translational Science Contribute to pharmacology strategy to demonstrate proof of mechanism and proof of concept. Design and interpret in vivo efficacy studies including model selection/characterization, study design, working with CROs to execute the study, and data analysis/presentation. Define exposure-response relationships. Collaborate on dose and schedule optimization. Cross-Functional Integration Partner with ADME/PK to integrate pharmacokinetics, biodistribution, and exposure-response modeling. Work closely with chemistry and protein engineering teams to guide design toward safer and more effective molecules. Collaborate with CMC and analytical teams to ensure appropriate characterization of each therapeutic component. Support regulatory strategy, including authoring and reviewing IND sections (e.g., nonclinical overview, tox summaries). Risk Assessment & Decision Making Develop safety assessment frameworks tailored to our pre-targeting approach. Drive candidate selection by balancing efficacy, exposure, and safety. Present findings and recommendations to leadership, board members, and external partners. Required Qualifications PhD, DVM, or equivalent in Toxicology, Pharmacology, or related discipline. 4+ years of industry experience in nonclinical safety and/or pharmacology. Demonstrated experience leading IND-enabling toxicology programs. Strong background in small molecules, biologics, or targeted delivery systems (e.g., ADCs, radioconjugates, bispecifics). Experience designing and interpreting in vivo toxicology and pharmacology studies. Familiarity with regulatory expectations (FDA/ICH) for nonclinical development. Preferred Qualifications Experience with pre-targeting strategies. Familiarity with bioorthogonal click chemistry (e.g., tetrazine–TCO systems). Background in oncology or other areas involving targeted therapies. Experience evaluating on-target vs. off-target toxicities in complex systems. Knowledge of safety considerations for reactive intermediates or payload-driven toxicity. Experience integrating PK/PD and tox data for translational modeling. Strong publication record and presentation skills. How We Work: We are a remote-first company, with occasional travel for in-person team meetings or scientific conference attendance. Core collaboration window: 9:00am–3:00pm Pacific Time. You are expected to be available during this time for meetings and real-time collaboration. Async + sync balance: Outside of core hours, we work asynchronously, but timely communication and follow-through are expected. Meetings: You should be comfortable joining video calls, sharing availability on calendar and actively participating during core hours. You should be comfortable working across common tools including Zoom, Google Workspace, Microsoft 365, Slack, and similar platforms. Benefits & Eligibility Compensation at Shasqi Competitive base salary as part of a broader total rewards package. Equity: Included as port of total compensations. Comprehensive benefits: medical, dental, vision, 401(k) match, short- and long-term disability. Flexible PTO and a WFH stipend to support remote work. Ongoing growth opportunities, professional development, and mentorship. Salary Range The anticipated base salary range for this role is $150K–$180K USD. Final compensation will depend on location, experience, skills, education, and internal equity. Our ranges are intentionally broad to reflect market conditions and the specialized nature of our work. Eligibility U.S.-based employees only. Must be authorized to work in the United States. We are not currently sponsoring visas. About Shasqi Shasqi is a biotech company advancing a new class of targeted cancer therapies, built on Nobel prize-winning technology called click chemistry. Backed by leading biotech investors, we are building a pipeline of first-in-class therapies that are designed to overcome the limitations of ADCs increasing efficacy and limiting toxicities. Our lead asset will be entering the clinic in early 2027. You can learn more about our company at www.shasqi.com Please Note: At this time, Shasqi is not partnering with external recruiting agencies. We kindly ask that agencies refrain from contacting us regarding this role. Shasqi is an Equal Opportunity Employer. We are committed to creating a diverse and inclusive workplace and do not discriminate on the basis of any protected characteristic under applicable law.