About Cartography Biosciences

Cartography Biosciences is advancing a differentiated oncology pipeline of antibody-based therapies designed to target tumors with unprecedented precision. The company’s ATLAS and SUMMIT discovery platforms are powered by an industry-leading, fully integrated dataset spanning hundreds of thousands of cell states across healthy tissues alongside large-scale single-cell profiling of patient tumors. By combining petabyte-scale proprietary data, machine learning, and AI-driven biological insights, Cartography is identifying highly specific tumor targets and logic-gated target combinations to generate therapies engineered for maximal tumor selectivity and meaningful patient impact. The company’s lead program, CBI-1214, is a T-cell engager in development for colorectal cancer. CBI-1214 entered the clinic in early 2026 and is currently enrolling and treating patients in a phase 1 trial.

We are looking for an Associate Director or Director of Protein Sciences to lead protein sciences and external manufacturing for our programs as they advance toward the clinic. You will be the technical lead for our CDMOs across process development, analytical development, and drug substance and drug product. You will also build and manage our research-stage expression, purification, and analytical and developability capabilities in house and through external CROs. 

This is a hands-on, hybrid role based onsite in South San Francisco. You will work at the bench alongside associate scientists while also managing external manufacturing partners and CROs. The role balances hands-on internal work with external program management, and we expect the scope to evolve as the team and Cartography's CMC organization grow. 

Key Responsibilities

External Manufacturing & CDMO Partnerships 

• Serve as the technical lead to our external manufacturing partners across cell line development, upstream and downstream process development, analytical method development, and GMP drug substance and drug product for gene to IND CMC programs 
• Ensure external programs deliver drug product to specification, on time, and on budget. 
• Communicate program progress, risks, and key decisions to the internal leadership team. 
• Support ongoing process development for clinical stage programs, including early high-concentration formulation development to enable subcutaneous dosing. 

Protein Expression 

• Build recombinant antibody expression, in house and through external CROs, spanning 96-well / deep-well high-throughput transient screening and mL-to-L bench-scale transient mammalian production (Expi293, ExpiCHO, transient CHO) to support research and in vivo studies (mouse efficacy / PK and non-GLP NHP). 
• Run the expression pipeline as an internal service with clear intake, prioritization, and turnaround, tracking titer, yield, and quality in ELN entries and a LIMS-backed registry. 
• Optimize transient production of multi-chain bispecific and multispecific assemblies (knob-into-hole heterodimers, VHH-containing trispecifics), including plasmid chain-ratio tuning to maximize correctly assembled product. 
• Increase expression and screening throughput to support AI/ML-driven design, build, and test cycles. 

Protein Purification 

• Build antibody and bispecific purification trains: Protein A capture with orthogonal polishing by ion exchange, hydrophobic interaction, and mixed-mode chromatography, plus analytical and preparative size-exclusion. 
• Develop format-specific strategies that resolve bispecific product-related species (heavy-chain homodimer, half-antibody, and light-chain-mispaired variants) from the correctly paired heterodimer. 
• Operate AKTA-scale chromatography and high-throughput magnetic-bead purification (KingFisher or equivalent) to support candidate triage and research supply. 
• Deliver low-endotoxin, high-monomer, clinically representative material meeting in vivo dosing specifications for pharmacology and toxicology studies. 

Analytical & Developability Characterization 

• Manage and improve internal developability and characterization capabilities (e.g., analytical SEC, HIC, DSF, CE-SDS (reduced and non-reduced), and DLS). 
• Confirm correct chain pairing and quantify product-related species (homodimer, half-antibody, mispaired variants) for bispecific and multispecific molecules. 
• Own developability triage and candidate ranking, and feed results into lead selection with Antibody Engineering colleagues. 

Team Leadership & Cross-Functional Work 

• Mentor and grow a small internal protein sciences team and set the day-to-day practices and priorities for the function. 
• Partner across Antibody Engineering, Computational Biology, Pharmacology, and program teams, and represent Protein Sciences in program reviews. 

Required Qualifications 

• PhD in protein science, biochemistry, biophysics, chemical or biological engineering, or a related discipline with 6+ years (Associate Director) or 9+ years (Director) of biopharmaceutical industry experience; or an MS with commensurate additional directly relevant experience. 
• Demonstrated experience managing external CDMOs to deliver large-molecule drug substance and drug product on time and on budget. 
• Familiarity supporting Module 3 (CMC) of IND filings. 
• Experience with bispecific antibodies or other complex antibody formats (e.g. knob-into-hole, multispecific, VHH / single-domain fusions). 
• Experience with mammalian expression and cell line development, including transient systems (Expi293, ExpiCHO) and stable cell line development. 
• Experience building and optimizing multi-step antibody purification trains on FPLC systems (AKTA or equivalent), including Protein A capture and common polishing modalities (IEX, HIC). 
• Working knowledge of core biophysical and analytical methods (analytical SEC, HIC, DSF, CE-SDS, DLS). 
• Developability triage experience translating biophysical data into candidate selection decisions. 

Preferred Qualifications 

• Experience with liquid-handling automation and high-throughput antibody purification and characterization. 
• High-concentration (greater than 100 mg/mL) subcutaneous formulation development and management of outsourced formulation programs. 
• Track record advancing a biologic through IND-enabling CMC. 
• Knowledge of T-cell engaging antibody platforms (TCEs, bispecifics, multispecifics) and a background in oncology or immuno-oncology. 
• Proficiency in a programming language (e.g. Python) and experience with AI-assisted or agentic coding tools.