---
title: 'Principal Associate Scientist, Bioanalytical Science at Xaira Therapeutics'
canonical: 'https://feeny.ai/job/principal-associate-scientist-bioanalytical-science-xaira-therapeutics-south-9a4gcetj8vab'
type: 'job'
last_seen: '2026-09-07'
---

# Principal Associate Scientist, Bioanalytical Science at Xaira Therapeutics

- **Company:** Xaira Therapeutics
- **Location:** South San Francisco California, United States
- **Posted:** 2026-08-31
- **Last confirmed live:** 2026-09-07
- **Apply:** https://job-boards.greenhouse.io/xairatherapeutics/jobs/5226047007

## Job description

## About Xaira Therapeutics

Xaira is an innovative biotech startup focused on leveraging AI to transform drug discovery and development. The company is leading the development of generative AI models to design protein and antibody therapeutics, enabling the creation of medicines against historically hard-to-drug molecular targets. It is also developing foundation models for biology and disease to enable better target elucidation and patient stratification. Collectively, these technologies aim to continually enable the identification of novel therapies and to improve success in drug development. Xaira is headquartered in the San Francisco Bay Area, Seattle, and London.

## About the Role

Xaira Therapeutics is seeking a Principal Associate Scientist to join our Bioanalytical Sciences team. This is a hands-on, lab-based role focused on developing and executing ligand binding assays to support pharmacokinetic, pharmacodynamic, and target engagement studies across discovery and translational programs.

This position is ideal for someone with strong experience in bioanalytical assay development and execution who enjoys bench work and contributing to data generation in a fast-paced, collaborative environment. You will work closely with scientists across biology and pharmacology to generate high-quality data that supports ongoing discovery efforts.

## What You’ll Do

- Develop, optimize, and execute ligand binding assays (ELISA, MSD/ECL) and flow cytometry-based methods to support PK, PD, receptor occupancy, and target engagement studies for biologic programs
- Support assay development, optimization, qualification, and validation activities for both non-GLP,IND-enabling GLP, and clinical studies
- Contribute to the design and execution of DMPK and bioanalytical studies, generating PK/PD and exposure data to support candidate selection
- Support bioanalytical method development, qualification, and validation for discovery, translational, and clinical programs
- Process and analyze samples across NHP and rodent matrices, including serum, plasma, and tissue
- Generate, analyze, and clearly document experimental data to support team decision-making
- Prepare presentations and data summaries to communicate experimental findings with internal program groups and external CROs.
- Maintain accurate lab records and ensure reproducibility of experimental workflows
- Collaborate with cross-functional teams to support ongoing research programs

## What We’re Looking For

- B.S. or M.S. in Biochemistry, Immunology, Analytical Chemistry, or a related field with 7+ years of relevant industry experience
- Strong hands-on experience with ligand binding assay platforms (ELISA, MSD/ECL)
- Proven experience executing flow cytometry-based assays, ideally for receptor occupancy or target engagement
- Experience supporting PK/PD sample analysis across NHP and/or rodent species in a discovery or translational research setting
- Ability to independently execute experiments and troubleshoot technical issues
- Past experience with summarizing data and presenting to internal or external groups.
- Strong attention to detail, organization, and record keeping
- Ability to work effectively in a fast-paced, team-oriented environment

## Compensation

Annual

We offer a competitive compensation and benefits package, seeking to provide an open, flexible, and friendly work environment to empower employees and provide them with a platform to develop their long-term careers. A Summary of Benefits is available for all applicants. We offer a competitive package that includes base salary, bonus, and equity. The base pay range for this position is expected to be $110,000 to $138,000 annually; however, the base pay offered may vary depending on the market, job-related knowledge, skills and capabilities, and experience.

Xaira Therapeutics an equal-opportunity employer. We believe that our strength is in our differences. Our goal to build a diverse and inclusive team began on day one, and it will never end.

TO ALL RECRUITMENT AGENCIES: Xaira Therapeutics does not accept agency resumes. Please do not forward resumes to our jobs alias or employees. Xaira Therapeutics is not responsible for any fees related to unsolicited resumes.

## About Xaira Therapeutics

## Company Overview
- **One-liner**: Xaira Therapeutics is an integrated biotechnology company applying artificial intelligence across the entire drug discovery and development process to design next-generation medicines.
- **Entity Type**: Private (Series A)
- **Headquarters**: South San Francisco, California, United States (with offices in Seattle, Washington, and London, UK)
- **Founded**: 2023
- **Founders**: Co-founded and incubated by ARCH Venture Partners and Foresite Labs, with foundational scientific contributions from Nobel Laureate Dr. David Baker (Institute for Protein Design, University of Washington).

## Core Business
- **Primary industry/industries**: Biotechnology, Drug Discovery & Development, Artificial Intelligence
- **Target customers**: B2B (pharmaceutical partners, biotech collaborators) and ultimately patients via its own therapeutic pipeline.
- **Mission or purpose statement**: "Pioneering the transformative artificial intelligence that will help discover and develop the next generation of life-changing medicines." [xaira.com](https://www.xaira.com/)

## Products & Services
- **AI-Powered Drug Discovery Platform**: An end-to-end platform integrating advanced AI research, expansive data generation (functional genomics, proteomics, multi-omics), and robust therapeutic product development to shift drug discovery from an empirical science to a precise engineering discipline. [xaira.com](https://www.xaira.com/our-approach)
- **Computational Protein Design**: Built on foundational work by Nobel Laureate Dr. David Baker, leveraging AI to design entirely new proteins from scratch for previously undruggable targets. [xaira.com](https://www.xaira.com/our-approach)
- **X-Cell (Virtual Cell Model)**: An AI model trained on billions of genomic data points to simulate and understand cellular biology. [xaira.com](https://www.xaira.com/)
- **Therapeutic Pipeline**: A pipeline of differentiated therapeutics across multiple modalities (small molecules, biologics, protein therapeutics) developed through an integrated AI-driven process.

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed. The company launched in 2023 with a $1 billion Series A financing, one of the largest in biotech history.
- **Key Metric**: Total Funding of $1 billion (Series A, 2023).
- **Notable Investors/Partners**: ARCH Venture Partners (co-founder and lead investor), Foresite Labs (co-founder and incubator), F-Prime Capital, and other top-tier investors. Board includes leaders from ARCH, Foresite, NEA, and Johnson & Johnson. Scientific advisors include Nobel Laureates Carolyn R. Bertozzi and David Baker, and other luminaries. [xaira.com](https://www.xaira.com/our-team)
- **Growth Signals**: Launched in 2023 with a record $1B Series A; rapidly building a world-class team across three global hubs (South San Francisco, Seattle, London); actively hiring across AI, computational biology, protein design, and drug development roles; announced X-Cell, a virtual cell model trained on billions of genomic data points. [xaira.com](https://www.xaira.com/)

## Competitive Advantages
- **Unprecedented Capital & Talent**: Launched with a $1B Series A, enabling aggressive hiring of top-tier AI and biology talent and long-term investment in infrastructure.
- **End-to-End AI Integration**: Uniquely positioned to apply AI across the entire drug discovery and development lifecycle, from target identification to clinical development, creating a powerful data flywheel.
- **World-Class Scientific Foundation**: Built on foundational AI protein design work from Nobel Laureate David Baker's lab, with a board and advisory board including multiple Nobel Laureates, former FDA commissioners, and industry leaders from Genentech, Johnson & Johnson, and top venture firms. [xaira.com](https://www.xaira.com/our-team)
- **Massive Data Generation**: Investing heavily in functional genomics and proteomics to generate proprietary, multi-dimensional datasets that fuel AI model development, creating a defensible data moat.

## Strategic Focus
- **End-to-End AI Integration**: Building predictive and agentic AI models across the complete drug discovery and development spectrum to increase probability of success, reduce timelines, and lower costs. [xaira.com](https://www.xaira.com/our-approach)
- **Data as a Core Asset**: Generating and integrating massive, multi-dimensional biological datasets (from molecular to human scales) to train and improve AI models continuously.
- **Pipeline Development**: Advancing a pipeline of differentiated therapeutics across multiple modalities (small molecules, biologics, protein therapeutics).
- **Talent Acquisition**: Aggressively hiring across AI research, engineering, computational biology, protein design, and drug development to build a world-class, interdisciplinary team.

## Why Work Here
- **Mission-Driven**: Opportunity to work at the forefront of AI and biology to fundamentally transform how medicines are discovered and developed, with the potential to impact millions of patients.
- **World-Class Team & Mentorship**: Work alongside and learn from Nobel Laureates, top AI researchers, and experienced drug developers from leading pharma and biotech companies. [xaira.com](https://www.xaira.com/our-team)
- **Interdisciplinary Culture**: A unique blend of AI/ML engineers, protein designers, computational biologists, and drug hunters all working together in a highly collaborative environment.
- **Global Hubs & Flexibility**: Offices in South San Francisco, Seattle, and London, offering multiple locations for talent.
- **Generous Resources**: Backed by a $1B Series A, providing the resources to pursue ambitious, long-term research without short-term funding pressure.
- **Job Scam Awareness**: The company has issued a warning about fraudulent job offers; all legitimate recruitment is conducted through official channels (Greenhouse) and never via Google Chat or requests for payment. [xaira.com](https://www.xaira.com/work-with-us)

## Sources
1. [xaira.com](https://www.xaira.com/)
2. [xaira.com](https://www.xaira.com/our-approach)
3. [xaira.com](https://www.xaira.com/our-team)
4. [xaira.com](https://www.xaira.com/work-with-us)
5. [greenhouse.io](https://job-boards.greenhouse.io/xairatherapeutics)

## Other roles at Xaira Therapeutics

- [Lab Software Engineer](https://feeny.ai/job/lab-software-engineer-xaira-therapeutics-south-san-francisco-california-mt9p82bbxdfp) — South San Francisco California, United States
- [AI Scientist Intern, Computational Protein Design](https://feeny.ai/job/ai-scientist-intern-computational-protein-design-xaira-therapeutics-seattle-cwyf0hr1nk3c) — Seattle Washington, United States / South San Francisco California, United States
- [Senior Scientist, Biology](https://feeny.ai/job/senior-scientist-biology-xaira-therapeutics-south-san-francisco-california-am8z6cjwb0xn) — South San Francisco California, United States
- [Facilities Coordinator II  - Lab Operations (Contract)](https://feeny.ai/job/facilities-coordinator-ii-lab-operations-contract-xaira-therapeutics-south-san-z65y9vbqwcce) — South San Francisco California, United States
- [AI in Residence, Computational Protein Design](https://feeny.ai/job/ai-in-residence-computational-protein-design-xaira-therapeutics-seattle-ns335n33bw1n) — Seattle Washington, United States
- [Lab Automation - Robotics Engineer](https://feeny.ai/job/lab-automation-robotics-engineer-xaira-therapeutics-south-san-francisco-dneqyyrnt1j5) — South San Francisco California, United States
- [Payroll Manager](https://feeny.ai/job/payroll-manager-xaira-therapeutics-south-san-francisco-california-cwj1ck4aywe9) — South San Francisco California, United States
- [Vice President, Business Development and Alliance Management](https://feeny.ai/job/vice-president-business-development-and-alliance-management-xaira-therapeutics-vyvtp8b00s9q) — South San Francisco California, United States
- [Senior Manager, Projects and Programs - Research](https://feeny.ai/job/senior-manager-projects-and-programs-research-xaira-therapeutics-south-san-j0pcpkzrc2pf) — South San Francisco California, United States
- [Senior Scientist, Functional Genomics](https://feeny.ai/job/senior-scientist-functional-genomics-xaira-therapeutics-south-san-francisco-x16av76axk2y) — South San Francisco California, United States