NexImmune Inc.
Gaithersburg, Maryland

Department: Protein Development and Manufacturing
Reports To: VP, PD/MFG
Status: Full Time/Exempt


Position Summary:

We are seeking Senior Scientist candidates with extensive biotech industry experience in developing, optimizing, and scaling up cell culture manufacturing processes from bench to pilot-scale production (preferably cGMP manufacturing).

Qualified candidates will demonstrate a broad and current technical/scientific knowledge of cell culture process development, optimization, and scale-up methodologies to develop robust, scalable, high-titer cell culture processes. Suitable candidates will have hands-on experience working with different mammalian expression systems, shaker and spinner flask cultures, single-use bioreactor systems, and have a thorough understanding of cell culture laboratory techniques and practices. Suitable candidates should have experience conducting cell line stability studies and establishing suitable process scale-down models. Candidates will need to demonstrate extensive experience conducting media screening, feed strategy, and bioreactor process parameter optimization studies to optimize cell growth and productivity.

In addition to the above, candidates for the Senior Scientist position will demonstrate additional working knowledge in or more of the following: statistical tools and DOE, QbD principles, scale-down model development and qualification, and process characterization studies. Senior scientist candidates should also have a good working understanding of current FDA and ICH guidelines and preferably have some IND CMC and regulatory filing experience.

Candidates must have excellent communication and writing skills, with extensive experience preparing technical documents (e.g. SOPs, protocols, technical reports, and/or batch records). Candidates must have a demonstrated ability to work independently, design and execute appropriately controlled experiments, analyze and interpret data critically, and maintain up-to-date laboratory notebooks.


  • B.A/B.S., M.S. or PhD. in life sciences or biochemical engineering with a minimum of 10 years of biotech industry experience in cell culture process development, optimization, and scale-up.
  • Basic knowledge of GxP guidelines for the biotech industry
  • Robust understanding of cellular biochemistry and metabolic pathways.
  • Hands-on experience with spinner and shaker culture, and mini/bench to pilot scale bioreactor systems.
  • Tech transfer and/or pilot- or large-scale cGMP manufacturing experience a plus.
  • Proficient with the use of MS Office software (Word, Excel, Power Point).
  • Excellent problem solving, organizational, and time management skills
  • Must demonstrate initiative and be self-motivated
  • Must have excellent communication and writing skills
  • Positive attitude and interpersonal skills and the ability to work in team-oriented environment are essential
  • Candidates must have a demonstrated ability to think critically and analyze and interpret data independently.
  • Can coordinate and prioritize parallel tasks.
  • Must be flexible and able to adapt to changing demands.
  • Senior Scientist position will demonstrate additional working knowledge in or more of the following: statistical tools and DOE, QbD principles, process characterization studies, FDA and ICH guidelines, IND and/or regulatory (CMC) filing experience.


  • Plan, design, execute, and record experiments, and independently analyze results using good scientific principles and with keen attention to detail and quality. Maintain an up-to-date GLP compliant lab notebook.
  • Develop, optimize, and scale up robust and high-yield cell culture fed-batch processes for pilot production and subsequent cGMP manufacturing of Phase I candidates.
  • Characterize cell lines and evaluate cell line stability and suitability for pilot/GMP manufacture.
  • Use DOE or other scientific methods to determine optimal growth parameters, media formulations, and feed strategies in small-scale shakers and mini-bioreactors.
  • Participate in transfer of cell culture processes to in-house pilot GMP production suite (or CMO if required) and conduct engineering and cGMP pilot manufacturing runs.
  • Write development reports (progress, summary, tech transfer), protocols, and SOPs.
  • Support drafting and/or revisions of production batch records for cGMP manufacturing as well as close-out of executed batch records with QA.


Qualified, interested candidates should send a resume to: