ADC DOWNSTREAM

Narrow DAR. Higher Yield. ADC Purification with MCSGP.

Less cytotoxin wasted. Isolate target DAR species without discarding on-target product to side-fractions — demonstrated on a Kadcyla®-type lysine-conjugated ADC model: 100% yield at 57% purity vs. 22% yield at 31% purity for batch (DAR 3.0) | up to 50% fewer synthesis operations (DAR 2.0)

Source: YMC ChromaCon ADC Application Note (CEX, Kadcyla®-type model)

Talk to Our Purification Specialists

Download the ADC Application Note

Talk to Our Purification Specialists

Download the ADC Application Note

The ADC Purification Challenge: DAR Heterogeneity

ADC demand is surging — with over a dozen FDA-approved products, hundreds of clinical candidates, and rapid market growth. But conjugation of cytotoxic payloads to antibody lysine residues or reduced cysteines produces a statistical mixture of DAR species. A narrow DAR distribution is a critical quality attribute — higher DAR species clear faster and cause more toxicity, while unconjugated antibody (DAR 0) is therapeutically inactive.

Hydrophobic interaction chromatography (HIC) is the primary preparative tool for DAR control, but the different DAR species have very similar adsorptive properties. Batch HIC forces a tight center-cut, discarding valuable on-target product in the side-fractions. For lysine-conjugated ADCs — where positional isomers further complicate resolution — batch yields for a specific DAR can be as low as 22–34%.

The Solution: MCSGP with AutoPeak® for ADC DAR Homogenization

MCSGP (Multi-column Countercurrent Solvent Gradient Purification) eliminates the purity-yield trade-off in ADC DAR purification. Two identical chromatographic columns continuously recycle impure DAR side-fractions — recovering on-target DAR product that batch chromatography would discard. The process uses the same resins, buffers, and gradient conditions as your existing batch ADC method — whether HIC, CEX, or mixed-mode.

AutoPeak® dynamic process control monitors the ADC elution profile in real-time via UV, automatically adjusting collection windows to maintain the target DAR distribution — enabling robust, unattended DAR polishing runs.

Same resins. Same buffers. Superior DAR control. MCSGP works with all major HIC, CEX, and mixed-mode resins — your existing batch ADC conditions are the starting point. Continuous side-fraction recycling recovers on-target DAR product from overlapping peaks, delivering up to 4× yield vs. batch. AutoPeak® compensates in real-time for conjugation variability and column aging, enabling unattended DAR polishing runs.

Learn About MCSGP with AutoPeak®

MSCGP

Proven Results: MCSGP vs. Batch for ADC DAR Purification

Up to 4×

Yield Improvement

+80%

Productivity Gain

55% ↓

Buffer Reduction

Case Study Part 1 — Study Design & DAR Purity/Yield Results

Model system: Trastuzumab + Atto-488 (NHS-ester, Kadcyla®-type lysine-conjugated ADC) | Mode: CEX — YMC BioPro IEX SmartSep S10 System: Contichrom CUBE 30 | Analysis: ESI-MS (Q-TOF Bruker Maxis Impact)

Target DAR	Batch Purity	Batch Yield	MCSGP Purity	MCSGP Yield	Yield Improvement
DAR 2.0	59.0%	34%	70.0%	61%	+80% (at higher purity)
DAR 3.0	30.9%	22%	57.1%	100%	4×
DAR 4.0	50.7%	56%	53.9%	92%	+50% (at higher purity)
DAR 5.0	47.4%	33%	48.1%	42%	+25%

MCSGP consistently delivered higher yield at equal or higher purity. All non-neighboring DAR species were eliminated (<5%). Uneven DARs (3.0, 5.0) were isolated at high yield — infeasible with both batch chromatography and site-specific conjugation.

Chromacon ADC Application Note. First published March 2024. Research funded by Eurostars project E! 9503. See related resources for download.

Case Study Part 2 — Process Economics & Safety (DAR 2.0)

Detailed process comparison for DAR 2.0 purification:

Parameter	Batch	MCSGP	Improvement
Purity	59.0%	70.0%	+11%
Yield	34%	61%	+80%
Productivity	0.11 g/L/h	0.20 g/L/h	+80%
Buffer consumption	142 L/g	64 L/g	−55%
Load	4.1 g/L	3.7 g/L	comparable

The yield increase from 34% to 61% avoids 50% of synthesis operations for the same product output — directly reducing isolator time, cytotoxin exposure, and potent compound handling. The same product can be purified in half the time or with half the column volume.

Operational benefits: no re-chromatography of side-fractions, single product pool per cycle (no fraction analysis), faster batch release, fewer operators required.

Chromacon ADC Application Note. First published March 2024. Research funded by Eurostars project E! 9503. See related resources for download.

The Contichrom® Platform: From ADC Development to Production

Contichrom® systems support HIC, CEX, mixed-mode, and RP continuous chromatography for ADC DAR polishing and antibody capture. Methods scale predictably from CUBE → TWIN LPLC Polishing.

Systems Overview

Contichrom® CUBE

The essential platform for chromatography process development. This versatile 100-bar benchtop FPLC system runs batch, integrated batch, and continuous chromatography — including MCSGP and CaptureSMB — out of the box. Develop purification processes for mAbs, peptides, oligonucleotides, ADCs, and viral vectors, with verified scale-up at over 100× to pilot and production systems.

Contichrom® TWIN LPLC – Capture

Accelerate biopharmaceutical capture chromatography at production scale. This sanitary GMP system uses CaptureSMB® with AutomAb® to maximize resin utilization — achieving up to 3× faster processing and 50% less Protein A resin and buffer consumption compared to batch. CIP-ready design for mAbs, viral vectors, ADCs, and recombinant proteins.

Contichrom® TWIN LPLC – Polishing

Bring continuous polishing to biopharmaceutical manufacturing at production scale. This sanitary GMP system uses MCSGP with AutoPeak® to eliminate the yield-purity trade-off achieving +10–50% absolute yield increase at target purity while reducing buffer consumption compared to batch. CIP-ready design for mAbs, viral vectors, ADCs, and recombinant proteins.

Systems Overview

ADC Multi-Step Workflow Note

More than DAR polishing. The Contichrom® platform addresses multiple steps in the ADC downstream workflow:

ADC Purification Step	Contichrom Capability	Scale
DAR polishing (post-conjugation)	MCSGP — continuous DAR homogenization with higher yield	CUBE (CEX, HIC) → TWIN LPLC (HIC)
Aggregate removal	MCSGP or batch HIC — co-separated with off-target DAR species	CUBE → TWIN LPLC
Free payload/linker clearance	2D integrated batch: CEX → desalting in one automated process	CUBE → TWIN LPLC
Antibody capture (pre-conjugation)	CaptureSMB® — 2.5× higher Protein A productivity, 30-40% less resin (BMS-validated for mAb capture)	CUBE → TWIN LPLC
Payload purification (small molecule)	MCSGP with RP — cytotoxin/linker-payload purification	CUBE → TWIN HPLC
Impurity enrichment	N-Rich — automated isolation of ADC-related impurities for characterization	CUBE

CaptureSMB®

ADC Applications

DAR Polishing & Post-Conjugation Cleanup:

Lysine-Conjugated ADCs (Broad DAR Distribution) Non-specific lysine conjugation produces the broadest DAR distribution (DAR 0–7+) with extensive positional isomers. MCSGP with CEX demonstrated up to 4× higher yield on a Kadcyla®-type model, including DAR 3.0 at 100% yield. Same principle applies to HIC.

Cysteine-Conjugated ADCs (DAR 0/2/4/6/8) Partial reduction of interchain disulfides produces five DAR species. HIC resolves these by hydrophobicity — but batch yields are low. MCSGP continuous HIC polishing on the TWIN LPLC recovers on-target DAR 2–4 product at production scale.

Site-Specific ADCs (THIOMAB, Engineered Cysteine, Glycoconjugation, AJICAP™) Site-specific conjugation narrows the DAR distribution but only produces even DARs (2.0, 4.0, 6.0). MCSGP sharpens the target peak further and uniquely enables uneven DARs (3.0, 5.0) that site-specific chemistry cannot access.

ADC Aggregate Removal Aggregates from hydrophobic payload self-association co-elute with high-DAR species late in HIC. MCSGP simultaneously removes aggregates while polishing DAR — combining two steps into one.

ADC Applications Continued..

Related Upstream & Downstream Steps:

Free Payload & Linker Clearance TFF handles most free drug removal, but some hydrophobic payloads (PBD dimers) resist TFF. CEX clears free payload effectively — mAb platform conditions often transfer directly. The CUBE runs batch CEX and 2D integrated batch workflows.

Cytotoxic Payload Purification (Pre-Conjugation) Auristatins, maytansinoids, PBD dimers, and camptothecin derivatives require high-purity RP purification before conjugation. MCSGP with RP-HPLC increases payload yield — reducing cost of these expensive, potent compounds.

Antibody Capture (Pre-Conjugation) The mAb intermediate requires Protein A capture before conjugation. CaptureSMB delivers 2.5× higher Protein A productivity and 30-40% less resin — validated by Bristol Myers Squibb for mAb capture from lab to GMP scale.

Learn About CaptureSMB with AutomAb®

Getting Started with ADC MCSGP

See the Contichrom® platform in action before you commit. Computationally assess MCSGP suitability for your ADC DAR polishing step from your existing batch HIC or CEX data. Develop your DAR fractionation method at lab scale on a Contichrom CUBE, then scale to the TWIN LPLC Polishing for manufacturing-scale ADC production.

See It First — Free Demo or Webinar

Not yet familiar with the Contichrom® platform? Start here. YMC ChromaCon offers no-charge demonstrations and introductory webinars tailored to your team.

On-site in Zurich (half day, 2–4 hours): see the CUBE in person, run ChromIQ® live, discuss your ADC DAR separation challenge with YMC ChromaCon application scientists
Remote webinar (1–3 hours): interactive live session covering MCSGP, CaptureSMB, N-Rich, ChromIQ® software, and the full Contichrom® ecosystem
Sessions can focus specifically on MCSGP for HIC/CEX-based DAR fractionation and the AutoPeak® DAR collection concept

→ Request a free demo or introductory webinar

Modeling Assessment for ADCs

Predict how MCSGP will perform on your ADC DAR separation before running any new experiments. YMC ChromaCon evaluates MCSGP suitability and estimates expected DAR yield and homogeneity improvements from your existing batch data.

Submit your batch HIC, CEX, or mixed-mode method details — chromatogram, gradient, resin, column dimensions — along with your conjugation reaction DAR profile
YMC ChromaCon evaluates MCSGP suitability, simulates operating points, and estimates expected yield and purity improvements for your target DAR species
MCSGP process design starts from a single batch chromatogram — data from any HPLC or FPLC system; no Contichrom® required
Typical timeline: 3–5 weeks from receipt of data; no material shipment required

→ MCSGP Process Modeling Service

Develop at Lab Scale — Rent or Purchase a CUBE

MCSGP DAR polishing method development is performed on the Contichrom CUBE using your existing HIC, CEX, or mixed-mode resin and buffer system. Available for rental or purchase.

ChromIQ® MCSGP Wizard builds the initial DAR polishing operating point from your batch chromatogram — first MCSGP run typically achievable within a day
Your current batch gradient conditions are the starting point — no new resin or buffer development required
AutoPeak® dynamic process control monitors the ADC elution profile in real-time via UV, automatically adjusting DAR collection windows to compensate for conjugation batch variability and column aging

→ Contichrom CUBE Rental Program

→ Purchase a Contichrom CUBE

Scale to GMP Production — TWIN LPLC Polishing

The MCSGP DAR polishing method transfers directly from the CUBE to the Contichrom TWIN LPLC Polishing for manufacturing-scale ADC production. YMC ChromaCon provides scale-up consulting and GMP documentation support.

Column chemistry (HIC, CEX, or mixed-mode) and gradient conditions are preserved at scale — no resin or buffer re-development required
AutoPeak® control logic transfers from CUBE to TWIN — the same dynamic DAR collection strategy operates at production scale
Four TWIN LPLC Polishing system sizes (300–2000) cover pilot through full production flow rates
GMP documentation support (IQ/OQ/PQ) and scale-up consulting available; TWIN LPLC Capture also supports CaptureSMB for upstream antibody capture — see the mAbs & Antibody Variants page

→ Scale-Up Consulting and Training

01 / 04

Ready to Improve Your ADC Purification Process?

Book a CUBE Rental Register for the Continuous Chromatography Workshop

How does MCSGP improve ADC DAR polishing yield?

MCSGP continuously recycles the DAR side-fractions that batch chromatography discards — recovering on-target DAR product from overlapping peaks. On a Kadcyla®-type model, MCSGP delivered up to 4× higher yield (DAR 3.0: 22% → 100%) at equal or higher DAR purity. The same principle applies to HIC, CEX, and mixed-mode separations.

Does MCSGP work with HIC for DAR separation?

Yes. HIC is the industry-standard preparative mode for ADC DAR control, and MCSGP is fully compatible with HIC resins (Butyl, Phenyl, PPG), ammonium sulfate gradients, and standard low-pressure conditions. The published feasibility study used CEX; HIC follows the same MCSGP process design. Both modes run on the Contichrom CUBE and TWIN LPLC.

Which ADC conjugation types benefit most from MCSGP?

Any ADC with residual DAR heterogeneity benefits. Lysine-conjugated ADCs (broadest DAR distribution) see the largest gains — up to 4× yield improvement. Cysteine-conjugated ADCs benefit from sharpening the DAR 2/4 window. Site-specific ADCs benefit from further narrowing, and MCSGP uniquely enables uneven DARs (3.0, 5.0) that site-specific conjugation cannot produce.

Can MCSGP remove aggregates and unwanted DAR species simultaneously?

Yes. High-DAR species and aggregates are both more hydrophobic and co-elute late in HIC. MCSGP’s three-fraction separation naturally routes these to waste while recovering target DAR product — combining DAR polishing and aggregate removal in a single chromatographic step.

What production-scale system is used for ADC MCSGP?

The Contichrom TWIN LPLC. HIC-based DAR polishing operates at low pressure (<5 bar), well within the TWIN LPLC’s 7.5 bar design pressure. Four system sizes (300–2000) cover pilot through full commercial production. The same TWIN LPLC also runs CaptureSMB for upstream antibody capture and batch chromatography.

Can the same Contichrom system run antibody capture and DAR polishing?

At development scale, the Contichrom CUBE runs CaptureSMB (Protein A capture), MCSGP (DAR polishing), batch chromatography, and 2D/3D integrated batch — covering the full ADC downstream on a single instrument. At production scale, the TWIN LPLC handles both CaptureSMB capture and MCSGP HIC DAR polishing.

How does MCSGP reduce safety risk in ADC manufacturing?

By increasing DAR 2.0 yield from 34% to 61%, MCSGP halves the number of conjugation synthesis operations needed for the same product output. This directly limits isolator time, potent compound handling, and cytotoxin exposure — while reducing raw material costs and expensive payload waste.

How does AutoPeak® handle conjugation batch-to-batch variability?

AutoPeak® monitors the ADC elution profile in real-time via UV, dynamically adjusting DAR collection windows to compensate for shifts in DAR distribution between conjugation batches, column aging, and retention time drift. This ensures consistent target DAR output despite variable feed composition — critical for ADCs where conjugation chemistry introduces significant batch variability.