Founding Scientist

Tessering Biosciences is a biotech startup developing small-molecule therapeutics and computational tools to advance women's health. Our approach is precise modulation of nuclear hormone receptor signaling at the tissue and sub-tissue level, enabling tolerable and effective solutions to unmet needs.

Our lead asset is a once-weekly, hormone-free oral contraceptive in lead optimization, a uterine estrogen receptor antagonist that offers a more targeted approach to preventing pregnancy than current oral and hormonal options, with the goal of mitigating side effects while improving convenience. Across our portfolio, we are working to better understand, model, and address the biological differences that contribute to the differential and disproportionate burden of disease experienced by women.

We're looking for an exceptional bench scientist to join our founding team and support our preclinical discovery and development programs. If you thrive with high agency, want your work to directly shape a company's trajectory, and are an innovator seeking to bring the frontier of drug development to women's health, this is the opportunity for you.

This role is for someone with gold hands, sharp scientific intuition, and the drive to do what could be the most important work of their career. We are seeking the kind of scientists who live at the most ambitious edge of their field, think across disciplines, and ultimately want to build and lead companies of their own someday.

Core Qualifications (Required)

• PhD in Pharmacology, Cell/Molecular Biology, Reproductive Biology, Endocrinology, or closely related field, with at least 3 years of postdoctoral or equivalent industry experience; OR MSc with 5+ years of rigorous hands-on preclinical research at the Scientist IV-V level.
• Exceptional technical execution: precise, reproducible, high-quality data across both in vitro and in vivo platforms.
• Ability to independently design, execute, troubleshoot, and interpret experiments with efficiency and rigor.
• Demonstrated ability to execute preclinical programs end-to-end, from assay development through a non-GLP data package ready for GLP and/or IND-enabling studies, with strong documentation habits and an eye toward future regulatory requirements throughout.
• Proficiency across cell-based in vitro assays: reporter gene assays, Western blot, cell proliferation assays, ELISA, qPCR, and immunohistochemistry.
• Experience working with multiple relevant cell lines (e.g., MCF-7, HepG2, endometrial, uterine epithelial, neuronal lines).
• Estrogen receptor (ERα/ERβ) binding affinity assays.
• Reporter gene / transactivation assays: ERE-luciferase, C3 promoter-luciferase, hepatic lipase promoter, and others across relevant cell backgrounds.
• MCF-7 proliferation and antagonism assays.
• Estrogenicity cell-based agonist/antagonist profiling.
• Nuclear receptor selectivity and transporter interaction screening panels.
• Extensive experience with rodent surgery and a full suite of in vivo rodent studies (ovariectomy, contraceptive efficacy, toxicology, reproductive toxicology models).
• Uterine wet weight and histological assessment in immature, ovariectomized, and intact rat models.
• Fertility and reversibility studies; basic reproductive toxicology screens. Acute and repeat-dose toxicology studies (multi-species).
• Rodent pharmacodynamic and behavioral models to assess physiological endpoints (vasomotor response, temperature regulation, locomotor activity, pain/nociception, etc.).
• Pharmacokinetic studies: single- and multi-dose PK, tissue distribution in mice and rats.
• Bone mineral density / osteopenia model; histomorphometry; collagen cross-link analysis.
• Lipid and cholesterol profiling from rodent plasma.
• Rodent surgery: ovariectomy, laparotomy with reproductive tract dissection and morphological assessment (including ovarian cyst evaluation), surgically-induced endometriosis models, and recovery management.

What Makes You Exceptional

• Publications or reports demonstrating experimental depth in related fields.
• Prior experience setting up or scaling a research lab, workflow, or screening platform at an early-stage company.
• Comfort interfacing with external vendors to extend in-house capabilities (i.e., prior biotech, CRO, and/or multi-institution collaboration experience).
• Track record of developing and validating novel assays from scratch.
• Experience with executing GLP studies.
• Ability to communicate complex data clearly to non-specialist audiences including investors and advisors.
• Comfortable working at the interface of wet lab and computational biology; experience generating high-quality datasets for computational analysis and partnering closely with computational biologists.
• Familiarity with tissue-selective hormone receptor biology and pharmacology.

What You’ll Design / Build / Own

• Lead execution of preclinical drug development plans end-to-end, with a pipeline focus on sex-specific biology.
• Development, submission, amendment, and ongoing management of IACUC protocols.
• Support strategy across the company, including experimental and preclinical plans, early-stage discovery, hiring, and portfolio and lifecycle management.
• Build in-house assay capabilities and SOPs that become core company infrastructure.
• Contribute directly to IND-enabling data packages and associated scientific writing, positioning programs for clinical and commercial success.
• Develop and define company culture and our standards for rigor, strategy, and velocity.
• Partner with computational team to encode learnings into our models.
• We move fast and focus on what matters most, taking smart risks and learning quickly from the data.
• We are resourceful and scrappy, doing more with less and finding creative ways around obstacles.
• We thrive in ambiguity and are energized by tackling complex, undefined problems.
• We are mission-driven and relentless about improving outcomes for patients.

What We Offer

Compensation & Equity

• Founding-team-level equity and substantial long-term upside; cash compensation aligned with pre-seed/seed stage, growing as the company grows.
• Co-author publication support.
• Professional development budget for conferences, courses, and continuous learning.

Impact & Growth

• Shape a category-defining company from the earliest stage with maximum ownership.
• Learn and engage with world-class advisors, clinicians, and researchers, build an unparalleled network.
• Directly impact seminal, underserved areas of women's health.