Oligonucleotide Therapeutics Scientist

Korsana Biosciences; Waltham (MA); On-site; USD 115,000 - 140,000; Full time

Job summary

Korsana Biosciences in Waltham, MA seeks a senior chemist to design and optimize chemically modified oligonucleotides, develop novel nucleoside analogs, and guide lead optimization through SAR campaigns.

Responsibilities include synthesizing oligonucleotides, interpreting SAR data, collaborating with biology and translational sciences, and overseeing external CROs to ensure timely project execution.

Qualifications

• Ph.D. or M.S. with oligonucleotide industry experience.
• Hands-on organic synthesis and nucleoside chemistry.
• Expertise in siRNA, ASO, PMO, or related modalities.
• Deep knowledge of oligonucleotide modification patterns.
• Experience with synthesis platforms and purification workflows.
• Strong analytical skills (LC-MS, RP-HPLC, IEX, CE, MALDI-TOF).
• Medicinal chemistry SAR campaigns for oligonucleotide therapeutics.
• Familiarity with delivery technologies for targeting and delivery.
• Experience supporting lead optimization and candidate selection.

Responsibilities

• Design and optimize chemically modified oligos to improve potency and delivery.
• Develop novel nucleoside analogs and backbone chemistries for oligos.
• Generate SAR data to guide lead optimization across chemistries.
• Design oligo libraries with bioinformatics and biology teams.
• Develop synthetic routes for oligonucleotide building blocks.
• Oversee synthesis, purification, and analytical characterization of oligos.
• Manage external CROs for experimental design and timelines.
• Apply analytical methods (RP-HPLC, IEX, LC-MS, CE, SEC) for characterization.
• Collaborate with biology and pharmacology to link chemistry and activity.
• Contribute to next-gen oligonucleotide platform technologies.
• Evaluate emerging technologies to enhance potency and safety.
• Maintain thorough technical documentation and communicate results.

Skills

Scientific creativity

Cross-disciplinary collaboration

Medicinal chemistry data integration

Independent yet collaborative

Strong communication skills

Problem-solving in pharma

Education

Ph.D. in Organic Chemistry/Medicinal Chemistry

M.S. with 2–5 years in oligonucleotide therapeutics

Hands-on organic synthesis & nucleoside chemistry

Therapeutic oligonucleotide chemistry expertise

Understanding of modification patterns & PK/PD

Oligonucleotide synthesis platforms & purification

Analytical skills: LC-MS, RP-HPLC, IEX, CE, MALDI-TOF

SAR campaign experience for oligonucleotides

Delivery technologies familiarity (GalNAc etc.)

Lead optimization & candidate selection experience

Tools

Automated solid-phase synthesis

Preparative HPLC

Job description

Korsana Biosciences in Waltham, MA seeks a senior chemist to design and optimize chemically modified oligonucleotides, develop novel nucleoside analogs, and guide lead optimization through SAR campaigns.

Responsibilities include synthesizing oligonucleotides, interpreting SAR data, collaborating with biology and translational sciences, and overseeing external CROs to ensure timely project execution.