Cell Line Development Senior Specialist (female/male)

Key responsibilities

• Lead end-to-end development of stable CHO cell lines, including vector evaluation, transfection, clone selection, and in-depth characterization.
• Independently execute and optimize complete cell line generation workflow (ranging from DNA to RCB), stability assessments, and upstream handover.
• Develop and refine and standardize platform CLD processes incorporating automation tools and high-throughput screening strategies.
• Troubleshoot complex technical challenges across molecular biology workflows, expression systems, and mammalian cell culture performance.
• Analyze molecular sequencing data, productivity metrics, growth, metabolite profiles, and product quality attributes (data from assays such as ELISA, Octet, HPLC, qPCR, and flow cytometry).
• Apply statistical and data-driven approaches to determine lead clones and assess process robustness.
• Collaborate closely with upstream process development, downstream development, analytical development, and quality teams.
• Actively contribute to cross-functional troubleshooting discussions and drive continuous improvement of CLD technologies and workflows.
• Maintain high-quality experimental documentation in ELNs and prepare clear technical reports.
• Contribute to CMC documentation (e.g., IMPD, IND, Module 3 sections related to cell line development).
• Evaluate and implement new technologies such as gene editing, improved selection systems (e.g., GS, DHFR), automation, and expression vectors.

Requirements

• PhD in Biotechnology, Cell Biology, Molecular Biology, or related discipline with 3-5 years of industry CLD experience (hands-on) or MSc with 6-8 years of experience in CLD (hands-on).
• Solid understanding of vector design, expression systems, and cell biology fundamentals relevant to biosimilars/ ADCs/ bispecific/ or other complex biologics development.
• Demonstrated ability to design experiments, analyze data, and draw technically sound conclusions independently.
• Good understanding of regulatory expectations for early-stage CMC and cell bank characterization.
• Working proficiency in written and spoken English.
• Availability to work five days a week, eight hours a day.
• Proficient in MS Office (Excel, PowerPoint, Word, Project).
• Effective communication skills and openness to new challenges and collaboration.
• Strong organizational skills with the ability to prioritize and multitask.
• Commitment to accuracy, timeliness, and continuous learning.

What we offer

• Employment at a leading company in Poland’s biotechnology sector.
• Engaging and meaningful professional challenges.
• Competitive salary with annual and special occasion bonuses.
• Attractive benefits package, including:
• Private medical care.
• Life insurance.
• Employee Pension Program (PPE) and Employee Retirement Support (PWE).
• One additional paid day off per year.
• Flex Benefits budget (choose from options like MultiSport or Pluxee lunch card).
• Financial support for skill development.
• Weekly fruit and vegetable days.
• Access to psychological support.

Important: Please ensure that your application is submitted in English. 

At Rezon Bio, we believe in diversity and equality. Our recruitment process is conducted in a fully transparent manner and with respect for non-discrimination principles – regardless of gender, age, orientation, gender identity, or other individual characteristics. We encourage all individuals who meet the requirements to apply, including women, men, and non-binary persons. What matters most to us is your experience, skills, and passion for achieving goals together!