hero

Join the teams building tomorrow.

Principal Scientist, Protein Analytics

Xaira Therapeutics

Xaira Therapeutics

Data Science
Brisbane, CA, USA
USD 164k-205k / year
Posted on Aug 29, 2025

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

We are seeking a Principal Scientist to join our team and contribute as a scientific leader at the bench. This role requires deep technical expertise and a hands-on approach to advancing the characterization of therapeutic proteins. The ideal candidate will have a strong background in biosensor technologies and biophysical characterization, with demonstrated experience in applying these tools to support therapeutic drug development. Expertise in Surface Plasmon Resonance (SPR) and Biolayer Interferometry (BLI) platforms is essential, particularly for conducting kinetic and affinity measurements, as well as high-throughput epitope binning. This role is critical for hit generation, lead optimization, and identification of developmental candidates. Applicants with prior experience in the pharmaceutical or biotech industry, especially those with a strong understanding of protein developability assessments, are strongly preferred.

About You

The successful candidate will be expected to work independently, drive scientific execution in the lab, and provide technical leadership on complex projects. Supervisory or mentorship experience is highly desirable, as is the ability to collaborate effectively within cross-functional teams spanning biology, in silico design, along with protein engineering. You are highly proficient in multiple analytical techniques employed for biologics discovery, multi-parameter optimization and development with hands-on experience in preclinical and CMC activities involving complex biologics. Strong communication skills and the ability to present scientific data to diverse audiences are essential. We are looking for a highly adaptable individual who can excel in a fast-paced, matrixed environment with shifting priorities and multiple responsibilities. This is a hands-on role suited for a scientist who is passionate about advancing drug discovery and development through innovation and scientific rigor.

Key Responsibilities

  • Determine biomolecular interactions via SPR and BLI based biosensors, including kinetics, affinity, cross-blocking, and binding/sample heterogeneity.
  • Utilize SPR for high-throughput screening and characterization to support various drug discovery programs.
  • Molecular assessment of early and later stage development candidates. Assays including CE-SDS, cIEF, aSEC, DSC/DSF, AC-SINS, forced degradation/stability, pH stability testing, high concentration formulation assessments and polyreactivity ELISA.
  • This will likely require innovative and creative approaches, such as developing new assays and high-throughput screening methods, as well as novel strategies for the early and rapid evaluation of drug candidate molecules.
  • Excellent record keeping and organization is a must
  • Strong collaboration with protein engineering and antibody generation teams for discovering diverse therapeutic molecules.

Qualifications

  • PhD or master’s degree with 8+ years of relevant industry experience, or equivalent demonstrated expertise. Proven experience in an industrial setting is strongly preferred.
  • Deep technical expertise in studying biomolecular interactions using SPR and BLI biosensors, with hands-on experience in analyzing kinetics, affinity, cross-blocking, calibration free concentration determination, and binding heterogeneity.
  • Working knowledge in analysing protein homogeneity and solubility using state of the art assays is preferred.
  • Proven track record in high-throughput binding assays and molecular characterization.
  • Experience in drafting patent applications and contributing to IND (Investigational New Drug) filings is highly desirable.
  • Additional background in protein expression and purification is a significant plus.
  • Track record of independently leading complex research projects while working collaboratively within cross-functional teams.
  • Committed to fostering an inclusive, respectful environment that embraces diverse perspectives. Demonstrated inclusive leadership through active listening and thoughtful engagement with all viewpoints.

Compensation

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. The base pay range for this position is expected to be $164,000 - $205,000 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.

Xaira Therapeutics is an equal opportunity employer. We value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, sex, gender, gender expression, sexual orientation, age, marital status, veteran status, or disability status. We will ensure that individuals with disabilities are provided reasonable accommodation to participate in the job application or interview process, to perform critical job functions, and to receive other benefits and privileges of employment. Please contact Human Resources to request accommodation.

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.