Associate Principal Scientist (APS), Conjugation Scientist

AstraZeneca; Cambridge; On-site; GBP 60,000 - 80,000; Full time

Job summary

A leading biopharmaceutical company is seeking an Associate Principal Scientist in Cambridge to spearhead the development of innovative bioconjugates. This role requires a PhD and 8 years of experience in bioconjugation. The successful candidate will lead projects, design antibody conjugates, and collaborate with cross-functional teams to push scientific boundaries. This position comes with a competitive salary and a comprehensive benefits package, emphasizing in-office collaboration.

Benefits

Flexible employee benefits fund

Pension contributions

Performance recognition scheme

Qualifications

• 8 years’ hands-on experience in bioconjugation/ADCs in Biotech/Pharma.
• Demonstrated track record progressing conjugate therapeutics.
• Proven ability to lead deliverables and present results.

Responsibilities

• Lead antibody-based conjugation projects for technology development.
• Design and synthesise high-quality antibody conjugates.
• Partner with cross-functional teams to set experimental strategy.

Skills

Deep expertise in bioconjugation chemistries

Protein expression and purification

Mastery of analytics

Lead deliverables and communicate progress

Education

PhD in Chemical Biology, Biochemistry or related field

Tools

SEC/HIC/RP-HPLC

LC-ESI-MS

Job description

Associate Principal Scientist (APS), Conjugation Scientist
Cambridge UK (On‑site)

About AstraZeneca

AstraZeneca is a global, science‑led, patient‑focused biopharmaceutical company that focuses on the discovery, development and commercialisation of prescription medicines for some of the world’s most serious diseases. But we’re more than one of the world’s leading pharmaceutical companies. At AstraZeneca, we are pioneering new frontiers by identifying and treating patients earlier, working towards the aim of eliminating cancer as a cause of death.

Come and join our AZ team where you will play a pivotal role in this exciting period of development!

As an Associate Principal Scientist, you'll spearhead the development of innovative bioconjugates, pushing the boundaries of science to develop life‑changing medicines. Join us in exploring new frontiers and making a significant impact on global healthcare.

Key Responsibilities:

• Lead antibody‑based conjugation projects for both technology development and inclusion in our bioconjugate portfolio.
• Conceive, design, and synthesise high‑quality antibody conjugates (Antibody‑drug conjugates, bispecifics/tri‑specifics, etc.) using lysine, cysteine, engineered‑cysteine and enzymatic chemistries.
• Select payloads and rationally design conjugate architectures to optimise stability, payload‑antibody ratios (DAR/PAR/OAR), pharmacology, and on‑target potency balance and efficacy.
• Lead hands‑on expression, conjugation and purification at small‑ to mid‑scale material (up to gram‑scale), establish robust SOPs, and deliver materials to internal stakeholders on schedule.
• Express and characterise antibodies, VHHs and fusion constructs; perform bioconjugation, binding assays, and developability assessments.
• Extensive experience in protein engineering related to antibody conjugate optimisation such as half‑life extension, effector silencing, Fc engineering for thermal stability.
• Own analytical QC across SEC, HIC, RP‑HPLC, IEX, native and denaturing SEC‑MS.
• Partner with cross‑functional teams (e.g., therapy area partners, senior leaders, protein engineering, bioanalytics, pharmacology) to set experimental strategy, interpret data, and move programmes through appropriate milestones.
• Contribute to IP (inventions/patents) and publications; present at internal governance and external conferences.
• Mentor junior scientists and (where applicable) matrix‑manage pipeline and technology projects in support of antibody‑conjugates by championing high standards in safety, quality, and scientific rigour.

Requirements:

• PhD (or equivalent) in Chemical Biology, Biochemistry, Pharmaceutical Sciences, Chemistry or a related field and 8 years’ hands‑on experience in bioconjugation/ADCs in Biotech/Pharma.
• Demonstrated track record progressing conjugate therapeutics (e.g., ADCs) through key discovery gates and into preclinical development.
• Deep expertise in bioconjugation chemistries (lysine, cysteine/engineered cysteine, enzymatic); ability to tailor conjugation routes to format, payload and developability constraints.
• Payload selection and linker‑payload design (cleavable/non‑cleavable; acid‑labile, enzyme‑cleavable; rebridging and site‑specific strategies); strong SAR approach.
• Protein expression and purification (IgG, VHH, fusion constructs) with hands‑on experience in bioconjugation, purification and QC release.
• Mastery of analytics: SEC/HIC/RP‑HPLC/SAX; LC‑ESI‑MS (native SEC‑MS and denaturing RP‑MS); data analysis and interpretation for batch release and comparability.
• Proven ability to lead deliverables, communicate progress to cross‑functional leadership, and present complex results to governance/senior stakeholders.
• Exposure to Fc‑engineering (e.g., FcγR mutations, half‑life modulation) with cell assay execution.
• Familiarity with display technologies and protein engineering concepts to support conjugation site selection and format design.
• Experience authoring patents/manuscripts and contributing to articles & grants; effective scientific writing.

Desirables:

• Experience in application of AI design methodologies for bioconjugate development i.e. payload site placement, conjugation efficiency, developability or stability.
• Functional and primary cell assay design and execution (ADCC/ADCP; internalisation; efferocytosis) and associated data analysis/statistics.
• Familiarity with dual‑payload strategies and rebridging approaches.
• Broad bioassay toolkit: reporter assays (luciferase/SEAP), flow‑based internalisation, confocal imaging, Incucyte‑based live‑cell readouts.

In Office Requirement:

When we put unexpected teams in the same room, we unleash bold thinking with the power to inspire life‑changing medicines. In‑person working gives us the platform we need to connect, work at pace and challenge perceptions. That’s why we work, on average, a minimum of five days per week from the office. But that doesn’t mean we’re not flexible. We balance the expectation of being in the office while respecting individual flexibility. Join us in our unique and ambitious world.

Why AstraZeneca?

At AstraZeneca's Oncology R&D business area, you’ll be part of a team playing a critical role in driving meaningful change in the way we predict, prevent and treat patients’ conditions. We’re actively embracing and investing in technology, harnessing digital, data and analytics to reimagine the future of healthcare and deliver improved outcomes to patients beyond core medical. We’re shaping the future, improving and speeding up portfolio development, improving the patient experience and outcomes at clinical trials. Join the team that is co‑creating a digital ecosystem with patients at its core.

Competitive salary and benefits package on offer.

The successful candidate will have access to a flexible employee benefits fund, including holiday purchase and flexible time off, pension contributions, Share Save Plans, a performance recognition scheme and a competitive, generous remuneration package.

Date Posted 12-Dec-2025

Closing Date 26-Dec-2025

Our mission is to build an inclusive and equitable environment. We want people to feel they belong at AstraZeneca and Alexion, starting with our recruitment process. We welcome and consider applications from all qualified candidates, regardless of characteristics. We offer reasonable adjustments/accommodations to help all candidates to perform at their best. If you have a need for any adjustments/accommodations, please complete the section in the application form.