Senior Scientist, Cardiac Preservation (Organ Perfusion)

Until; San Francisco (CA); On-site; USD 110,000 - 150,000; Full time

Benefits offered by this job

Generous medical, dental and vision insurance

Flexible time off and paid holidays

Competitive compensation package

Access to a 401(k) retirement savings plan

Daily lunch and dinners

Monthly learning stipend

On-site fitness center

Quarterly team social budget

Job summary

Until, a pioneering company in organ preservation based in San Francisco, is seeking a Senior Scientist, Cardiac Preservation to lead their heart preservation initiatives. This role requires deep expertise in cardiac physiology and ex vivo heart perfusion to design and execute experimental protocols that facilitate reversible cryopreservation of the heart.

You will be responsible for maintaining cardiac viability assessments both before and after cryopreservation, tackling complex problems with a collaborative team, and contributing to groundbreaking advancements in organ preservation.

Qualifications

• Deep expertise in ex vivo heart perfusion, ideally including normothermic machine perfusion.
• Intimate understanding of cardiac physiology and biology.
• Experience designing and running organ viability assessments.

Responsibilities

• Develop and execute ex vivo heart perfusion protocols.
• Build out heart viability assessment toolkit.
• Propose adjustments to cryoprotectant formulations and protocols.

Skills

Ex vivo heart perfusion expertise

Understanding of cardiac physiology

Organ viability assessment

Complex experimental protocols

Problem solving

Education

PhD in a STEM field

4+ years experience in industry

Job description

Until is a moonshot company building a 'pause button' for biology. Our near-term focus is organ‑scale reversible cryopreservation: preserving donated organs at subzero temperatures without ice formation, then rewarming them uniformly for transplant. By solving this grand challenge, we're laying the foundation for whole‑body reversible cryopreservation, giving patients a bridge to future cures.

To achieve our goal, we are assembling an interdisciplinary team to develop perfusion systems, cryoprotectant formulations, and vitrification and rewarming hardware.

We envision a future where no transplantable organ is lost to logistics, and no terminal diagnosis is final because patients can safely wait for future medicine to arrive.

About The Role

We are seeking a Senior Scientist, Cardiac Preservation to lead our heart preservation efforts within the whole organ preservation team. You will own a large domain and play a vital role in shaping how Until preserves, recovers, and assesses the viability of the heart through cryopreservation. Drawing on deep expertise in cardiac physiology and ex vivo heart perfusion, you will design and execute the experiments that make reversible cryopreservation of the heart a reality.

What You'd Do

• Develop and execute ex vivo heart perfusion protocols, including normothermic machine perfusion (NMP), to maintain and evaluate cardiac viability before and after cryopreservation.
• Build out the heart viability assessment toolkit, including contractile and hemodynamic function, perfusion metrics, metabolic and lactate profiling, histology, and omics.
• Propose and test adjustments to cryoprotectant formulations, loading/unloading, cooling, and rewarming protocols to optimize cardiac health and recovery.
• Translate detailed knowledge of cardiac physiology and biology into experimental design and interpretation across the team.

About You

• Deep, hands‑on expertise in ex vivo heart perfusion, ideally including normothermic machine perfusion (NMP) of the heart.
• Intimate understanding of cardiac physiology and biology, including myocardial metabolism, contractile function, and ischemia/reperfusion injury.
• Experience designing and running organ viability assessments and interpreting multimodal readouts (functional, metabolic, histological, omics).
• Comfort working at the bench in an ex vivo model and a track record of executing complex experimental protocols.
• Demonstrated success working through hard, open‑ended problems, with a passion for rapid problem solving and rapid exploration of unfamiliar topics and protocols.
• Ability to think from first principles and tackle complex, cross‑disciplinary problems alongside other scientists and engineers.

Preferred Qualifications

• PhD in a STEM field, ideally in cardiac physiology, organ preservation, or transplant — or significant (4+ years) experience as a scientific leader in an industry context.
• Direct experience with cardiac transplant or heart preservation research.

Benefits

• Generous medical, dental and vision insurance coverage
• Flexible time off and paid holidays
• Competitive compensation package, including salary and equity
• Access to a 401(k) retirement savings plan
• FSA and commuter benefits
• Daily lunch and dinners, plus a variety of snacks
• Monthly learning stipend
• On‑site fitness center
• Quarterly team social budget