Principal Scientist, Mitochondrial

Principal Scientist, Mitochondrial & Cellular Toxicity

This role will be accountable for the application of laboratory technical support and specialist advanced cellular modelling approaches to generate data to elucidate mechanisms of toxicity, understand species differences, identify novel translational safety biomarkers, and inform project decisions.

With knowledge and experience of cell culture and advanced cellular models (e.g. Complex In Vitro Models, Human Model Systems, Micro Physiological Systems, and/or Organ on Chip models), the Principle Scientist will conduct paper & laboratory-based studies in support of predictive, mechanistic, and translational toxicological investigations across new drug modalities (Oligos, ADC, T-Cell Engagers, etc.) for projects in discovery and development.

In addition, the scientist will provide subject matter expertise (SME) for specific technical or scientific areas e.g. organ toxicities, cell model techniques.

Please note that due to the requirements of the role, this will be a lab-based position requiring a regular on-site presence at GSK Stevenage.

This position has been agreed to be at the G8 level but for exceptional candidates may be considered at the G7 level.

We create a place where people can grow, be their best, be safe, and feel welcome, valued and included. We offer a competitive salary, an annual bonus based on company performance, healthcare and wellbeing programmes, pension plan membership, and shares and savings programme.

We embrace modern work practises; our Performance with Choice programme offers a hybrid working model, empowering you to find the optimal balance between remote and in-office work.

Discover more about our company wide benefits and life at GSK on our webpage Life at GSK | GSK

In this role you will

• Design and execute innovative investigative toxicology experiments or technical work programs to support Project Issues with limited supervision; work includes study planning, experiment organization, sample preparation, data generation, processing, analysis and reporting.
• Plan next steps based on interpretation of results in collaboration with the Investigative Lead.
• Contribute to establishment and maintenance of scientifically current, state-of-the-art laboratory environment.
• Lead development of new cellular assay formats/techniques (from tissues, primary cells, or cell culture systems) for the investigation of mechanisms and translation of organ and cellular toxicities and safety risks to the clinic, including routine mammalian cell screening assays.
• Provide high quality data, acceptable to appropriate principles of data integrity (DI), including quality control (QC) of study data.
• Be a subject matter expert in your field with theoretical and technical understanding. Provide expert advice to Project Teams, advisory Safety Panels, Target Safety Reviews and external partners etc within your specialised area, as required.
• Where needed understand the disease target under investigation, and if applicable the therapeutic area, and the programme/project plan and potential safety issues of assigned projects / studies.
• Collaborate with all areas involved in a study to optimise study efficiency and quality to meet project goals and timelines.
• Prepare detailed oral or written reports and interim summaries within agreed timelines.
• Ensure clear, concise timely communication, and provide accurate information to study / report tracking system(s).
• May take a leadership role for specific enabling functions such as safety, facilities, compliance or data integrity on behalf of the group.
• Participate in collaborations (with internal and external partners) to assist the development and deployment of new approaches to improve the efficiency, prediction, mechanistic understanding, and translation of drug safety risks.
• Ensure compliance with GSK SOPs and Policies, GLP, and data integrity, safety, and animal welfare guidelines.

Why you?

Basic Qualifications & Skills:

We are looking for professionals with these required skills to achieve our goals:

• MSc or PhD or equivalent by experience in Molecular biology, Cellular biology, Toxicology and/or other related biological science. 
• Experience of cellular biology using advanced cellular systems and investigative safety/toxicology studies and their conduct, ideally within a Pharmaceutical or Research Institute setting, and a subject matter expert for a specific technical area, e.g. certain types of in vitro cellular models, or organ toxicity (liver, kidney, bone marrow), etc.
• Significant knowledge of and proficiency in routine and advanced cellular techniques and how to interpret and contextualise data for purpose of risk assessment.
• Having experience of providing technical subject matter expertise to Project Teams, Safety Project Specialists, and other stakeholders, including provision of integrated assessments of pre-clinical toxicity data would be an advantage.
• Understanding of modelling platform applications with the potential to support adverse outcome pathways and translation from non-clinical species to humans e.g., assist with pre-clinical investigations on toxicity issues arising pre-clinically and clinically with both small and large molecules (and across a variety of modalities).
• Proficiency in laboratory and in silico techniques to build and implement new human relevant cell models or other assays to fill strategic gaps and meet Project needs; with, ideally, an increasing focus on large molecules.
• Excellent written and verbal communication and organisational skills, ideally with evidence of a relevant publication record.
• Ability to work routinely across boundaries as part of cross functional matrix teams internally and potentially externally (inc. authorship and presentation of scientific content).
• Familiar with platform data and bioinformatics software and working with data analysts/bioinformaticians to leverage high content data approaches to support toxicological mechanism of action studies and risk assessment.

Closing Date for Applications – 12th of November, 2025 (COB)

Please take a copy of the Job Description, as this will not be available post closure of the advert. 

When applying for this role, please use the 'cover letter' of the online application or your CV to describe how you meet the competencies for this role, as outlined in the job requirements above. The information that you have provided in your cover letter and CV will be used to assess your application.

At GSK, we have bold ambitions for patients, aiming to positively impact the health of 2.5 billion people by the end of the decade. Our R&D focuses on discovering and delivering vaccines and medicines, combining our understanding of the immune system with cutting-edge technology to transform people's lives. GSK fosters a culture ambitious for patients, accountable for impact, and committed to doing the right thing, making sure that we focus our efforts on accelerating significant assets that meet patients' needs and have the highest probability of success. We're uniting science, technology, and talent to get ahead of disease together.

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Our approach to R&D.   

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Uniting science, technology and talent to get ahead of disease together.

GSK is a global biopharma company with a purpose to unite science, technology and talent to get ahead of disease together. We aim to positively impact the health of 2.5 billion people by the end of the decade, as a successful, growing company where people can thrive. We get ahead of disease by preventing and treating it with innovation in specialty medicines and vaccines. We focus on four therapeutic areas: respiratory, immunology and inflammation; oncology; HIV; and infectious diseases – to impact health at scale.

People and patients around the world count on the medicines and vaccines we make, so we're committed to creating an environment where our people can thrive and focus on what matters most. Our culture of being ambitious for patients, accountable for impact and doing the right thing is the foundation for how, together, we deliver for patients, shareholders and our people.

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