JLSa2, founded in 2024, is a well-resourced, seed-stage venture backed company located in South San Francisco currently developing a robust pipeline of novel protein-drug conjugate therapies to better address human metabolic diseases and other non-oncology related diseases.

 

The Senior Protein & Peptide/Chemical-Protein Conjugate Formulation Scientist is a technical leader responsible for the development, optimization, and characterization of stable formulations for protein- and peptide/chemical conjugates-based therapeutics. This role provides deep subject-matter expertise in biophysical characterization, formulation design, and stability strategy, supporting programs from late discovery through clinical development.

 

The position combines hands-on experimental work with technical leadership, cross-functional influence, and strategic input into developability and CMC decisions.

 

Key Responsibilities

Formulation Development & Strategy

  • Design and optimize formulations for proteins and peptide/chemical-protein conjugates (liquid, long-acting, oral and high-concentration)
  • Develop formulation strategies that address stability, aggregation, degradation, and delivery challenges
  • Support route of administration and dosage form selection for subcutaneous and oral routes
  • Lead formulation risk assessments and mitigation strategies

Biophysical & Analytical Characterization

  • Apply biophysical techniques to assess stability and developability (e.g., DSC, DLS, CD, SEC, HIC, rheology, subvisible particles)
  • Interpret stress and forced degradation data to guide formulation decisions
  • Collaborate with analytical teams on method development and comparability

Program & Cross-Functional Leadership

  • Serve as formulation lead on cross-functional project teams
  • Provide formulation input to candidate selection and early CMC strategy
  • Support tech transfer to development, manufacturing, and external partners
  • Contribute to IND-enabling and regulatory documentation (CMC sections)

Mentorship & Scientific Leadership

  • Mentor junior formulation and analytical scientists
  • Establish best practices, workflows, and technical standards
  • Act as a subject-matter expert in internal reviews and governance forums

External Collaboration

  • Manage and oversee formulation activities with CROs and CDMOs
  • Evaluate new formulation technologies and excipient strategies
  • Stay current with advances in protein and peptide formulation science

 

Required Qualifications

Education & Experience

  • PhD in pharmaceutical sciences, chemical engineering, biochemistry, or related discipline
  • 5–10+ years of industry experience in protein and/or peptide formulation
  • Deep expertise in biologics and drug-conjugates formulation and stability science
  • Experience with high-concentration formulations and/or long-acting injectables
  • Experience with oral delivery formulations
  • Proven track record supporting clinical candidates
  • Strong experimental design, data interpretation, and problem-solving skills

Preferred Qualifications

  • Familiarity with device compatibility and combination products
  • Familiarity with Auntie and Big Tuna and other Unchained analytical tools
  • Experience with global regulatory filings (IND/IMPD)
  • Prior experience in biotech or fast-paced development environments

Key Competencies

  • Scientific rigor and technical depth
  • Cross-functional leadership without direct authority
  • Strategic thinking with hands-on execution
  • Clear scientific communication and documentation
  • Mentorship and team development

 

Reporting Structure

  • Reports to: VP of Protein Engineering
  • Role level: Senior individual contributor with project leadership responsibilities

 

Salary Range: $175,000 to $200,000+ (Compensation will be commensurate with experience/expertise/level and could fall outside of the stated range)