What ADC conjugation methods does ProteoGenix offer?

ProteoGenix offers three antibody-drug conjugation approaches: site-specific Click chemistry, enzymatic conjugation, and random conjugation. Our proprietary cysteine rebridging technology enables site-specific conjugation of compatible native antibodies without prior engineering, with controlled drug-to-antibody ratios (DAR). Enzymatic conjugation provides defined attachment sites, while random conjugation can be suitable for early-stage research and feasibility studies. The most appropriate method depends on your antibody, payload, target DAR, and development objectives.

Can you conjugate my existing antibody without prior engineering?

Yes. Our proprietary cysteine rebridging Click chemistry can enable site-specific conjugation of suitable native antibodies without introducing engineered conjugation sites. Compatibility depends on the antibody’s structure and the selected linker-payload combination. We begin with a feasibility assessment to evaluate the conjugation strategy before proceeding to larger-scale production.

What drug-to-antibody ratios (DAR) can you achieve?

Our proprietary Click chemistry platform can target DAR 1, 2, or 4, depending on the conjugation strategy and molecular requirements. The resulting DAR distribution is assessed using analytical methods such as HIC-HPLC and mass spectrometry. The achievable DAR profile depends on the antibody, payload, and conjugation conditions.

How much antibody do I need to start an ADC conjugation project?

For the standard workflow, ProteoGenix requests approximately 2.5 mg of purified antibody for feasibility testing and 10 mg for full-scale conjugation. Input material requirements, including concentration and purity, are reviewed before starting the project. If you do not have sufficient antibody material, we can also support recombinant antibody production.

Can I provide my own payload or linker?

ProteoGenix can evaluate customer-supplied payloads and linkers for compatibility with the selected conjugation technology. Our conjugation capabilities cover different payload types, including cytotoxic drugs, nucleic acids, and fluorophores. Cleavable, non-cleavable, and custom linker strategies can be considered according to the project. Payload and linker compatibility is confirmed during the feasibility assessment.

How long does ADC conjugation and development take?

Our ADC conjugation service starts from 3 weeks, depending on the project requirements. The workflow includes an initial feasibility study, typically lasting 1–2 weeks, followed by conjugation, purification, and analytical characterization. The overall timeline depends on antibody compatibility, payload availability, required quantities, and the selected analytical package.

What analytical characterization and deliverables are included?

ProteoGenix provides purified ADC material together with analytical data relevant to the selected conjugation strategy. Characterization can include: Drug-to-antibody ratio (DAR) and DAR distribution Purity and aggregation assessment Antibody integrity Unconjugated antibody content Conjugation-related analytical data Methods include HIC-HPLC, SEC-HPLC, SDS-PAGE, and mass spectrometry. The standard conjugation package described on this page includes 5 mg of purified ADC material, with the final deliverables confirmed during project scoping.

Can ProteoGenix produce and optimize my antibody before ADC conjugation?

Yes. ProteoGenix can support your project from antibody discovery and recombinant production through optimization and ADC conjugation. If your antibody requires further development, our complementary services include: Affinity maturation to improve target binding. Antibody humanization to reduce non-human sequence content while aiming to preserve binding properties. Antibody developability assessment to evaluate properties such as stability, aggregation, and manufacturability. Recombinant antibody production to generate material for conjugation and downstream studies. Our team can help identify which development steps are relevant before starting your ADC conjugation project.

What are the intellectual property and licensing conditions for ADC development?

IP and licensing conditions depend on the conjugation technology and the intended use of the resulting ADC. ProteoGenix offers a proprietary Click chemistry platform with direct licensing arrangements. Research-stage services and potential clinical or commercial applications may involve different contractual conditions. Our team can clarify the applicable IP and licensing terms during project evaluation.

CUSTOM ANTIBODY DRUG CONJUGATE SERVICES

Antibody Drug Conjugate (ADC) Services

Site-specific ADC conjugation without prior antibody engineering. Transform your existing antibody into a conjugate with controlled DAR using our proprietary Click chemistry, supported by analytical characterization.

✓

Up to 90% of antibody molecules at the selected DAR

Target DAR 1, 2 or 4 using proprietary Click chemistry on native antibodies.

No prior antibody engineering From 3 weeks Site-specific Click chemistry

Discuss Your ADC Project See Experimental Results

ADC CONJUGATION TECHNOLOGIES

ADC Conjugation: Speed Meets Precision

Traditional ADC conjugation methods often involve trade-offs between site specificity, DAR control and antibody preparation. ProteoGenix Click chemistry enables site-specific conjugation without prior antibody engineering, combining precision with a streamlined development process.

	Random conjugation	Enzymatic conjugation	ProteoGenix Click chemistry
Antibody engineering	No	Generally required, depending on the method	✓ No prior engineering
DAR control	Heterogeneous	Controlled	✓ Target DAR 1, 2 or 4
IP & licensing	Depends on the linker-payload technology	Depends on the enzyme and conjugation platform	✓ Clear IP licensing terms
Development considerations	Product heterogeneity	Potential engineering and licensing requirements	✓ Compatible with existing antibodies
Main advantage	Established approach	Site specificity	✓ Site specificity without prior antibody engineering

FROM NATIVE ANTIBODY TO ADC

From Native Antibody to a Characterized ADC

Our proprietary Click chemistry rebridges the antibody’s own interchain disulfide bonds. Your antibody keeps its native sequence, while the payload is attached at defined sites for a controlled DAR.

Native IgG antibody showing its interchain disulfide bonds

Native antibody

Your existing IgG, with its native interchain disulfide bonds. No sequence engineering.

Cysteine rebridging

Disulfides are reduced and rebridged with a proprietary Click linker.

Site-specific antibody-drug conjugate with payloads attached at defined sites

Site-specific ADC

Payload at defined sites. Target DAR 1, 2 or 4, with up to 90% of antibody molecules at the selected DAR.

Interchain disulfide (S–S)
Click linker
Payload

Project timeline From feasibility to purified, characterized ADC

Custom cell line development timeline: stable pools in 6–11 weeks with 300 mg/L guarantee, VIPS single-cell cloning in 8–11 weeks with 1 g/L guarantee, RCB and stability study, 3–4 months total

Timelines are indicative and confirmed after technical review of your antibody, payload and target DAR.

Discuss Your ADC Project →

3 ADC Conjugation Services to Generate Your Custom ADC

Choose the conjugation approach that fits your development needs.

Click Chemistry

Controlled site-specific ADCs and dual-payload projects.
- DAR 1, 2 or 4
- No antibody engineering required
- Dual-payload conjugation
- Broad payload compatibility: drugs, RNA, DNA and fluorophores
Exclusive patented ProteoGenix technology
Enzymatic

Site-specific conjugation at defined sites.
- High DAR control at engineered sites
- Antibody engineering required
- Dual-payload conjugation
- Broad payload compatibility
Relies on third-party intellectual property
Random

Conjugation for early feasibility and R&D.
- Non-site-specific conjugation
- Highly variable DAR
- No antibody engineering required
- Limited to selected drug molecules
Relies on third-party intellectual property

Experimental evidence

2 Experimental Comparisons with Marketed ADCs

Explore how ProteoGenix site-specific conjugation technology performed in comparative studies with Adcetris® and Kadcyla®. Select a study to jump to its results.

COMPARISON 01

Brentuximab ADC

ProteoGenix vs. Adcetris®

CD30+ lymphoma model

Explore results ↓
COMPARISON 02

Trastuzumab ADC

ProteoGenix vs. Kadcyla®

HER2+ breast cancer model

Explore results ↓

Comparison 01

Brentuximab ADC: ProteoGenix vs. Adcetris®

CD30+ lymphoma model

Site-specific brentuximab ADC produced using proprietary cysteine rebridging technology, compared with marketed Adcetris®.

67% vs. 36%

Molecules at DAR 4

3% vs. 9%

Unconjugated antibody (DAR 0)

0.104 vs. 0.105 nM

EC50 on Karpas 299 cells

5/8 vs. 2/8

Mice alive at day 59

DAR DISTRIBUTION

A More Defined DAR Profile

DAR 4 was the dominant species in the ProteoGenix ADC, compared with the broader DAR distribution observed for Adcetris®.
IN VITRO POTENCY

Comparable Potency In Vitro

The two ADCs showed similar EC50 values against Karpas 299 cells: 0.104 nM versus 0.105 nM.

IN VIVO RESULTS

Tumor growth inhibition and survival

The ProteoGenix ADC produced stronger tumor growth inhibition in the presented model, with 5 of 8 mice remaining alive at Day 59 compared with 2 of 8 for Adcetris®.

Comparison 02

Trastuzumab ADC: ProteoGenix vs Kadcyla®

HER2+ breast cancer model

ProteoGenix developed a site-specific trastuzumab ADC using its proprietary cysteine rebridging technology and evaluated it against T-DM1 (Kadcyla®). Our study demonstrates a more controlled conjugation wile preserving key antibody properties.

63%

Average DAR: 4.0

ADC species at DAR 4

≈ 1–2 ng/mL

vs. ≈ 9–10 ng/mL

Free MMAE after 96 h in human plasma

5 mg/kg

In vivo dose

Near-complete tumor growth suppression in the tested model

HER2+

BT-474 cells

Antigen binding preserved after conjugation

DAR DISTRIBUTION

Defined DAR 4 population

The reported DAR profile shows 63% at DAR 4, with an average DAR of 4.0.
ANTIGEN BINDING

HER2 binding retained

Binding curves measured on BT-474 (HER2+) cells remain close to those of the reference antibodies.
PAYLOAD STABILITY

Lower free MMAE release

The MF-TTZ-MMAE curve remains below the FGM-TTZ-MMAE curve during the tested interval.
IN VIVO RESULTS

Tumor growth control at 5 mg/kg

The original plot shows the MF-TTZ-MMAE group near baseline while the T-DM1 group retains measurable tumor volume.

FROM FEASIBILITY TO DELIVERY

ADC Development Workflow

A feasibility-led approach to custom antibody conjugation, with analytical characterization built into the project.

01

Feasibility assessment

Evaluate your antibody, payload and target DAR to define suitable conjugation conditions.
02

Site-specific conjugation

Apply the agreed conjugation strategy using proprietary Click chemistry on compatible native antibodies.
03

Purification & characterization

Purify the ADC and evaluate drug loading, purity and antibody integrity.
04

Project delivery

Receive the agreed ADC preparation and analytical information for your next development decisions.

What Will You Receive at Each Stage?

Feasibility Study

Feasibility Study Deliverables

Analytical results and optional test material to assess conjugation feasibility before scale-up.

Included in the package

✓ Analytical feasibility report
✓ SDS-PAGE, SEC-HPLC (purity) and HIC-HPLC (DAR distribution and homogeneity)
✓ Test ADC material upon request (~1 mg on average)

Optional feasibility sample

~1 mg of test ADC material, upon request.

Full Conjugation

Scaled Conjugation Deliverables

Purified ADC material and comprehensive analytical characterization following conjugation.

Included in the package

✓ 5 mg conjugated antibody, sterile in PBS
✓ >90% target DAR species
✓ Full analytical report: SDS-PAGE, SEC-HPLC, HIC-HPLC and mass spectrometry (MS)

Final ADC characterization

SDS-PAGE, SEC-HPLC, HIC-HPLC and MS.

IND-ENABLING DATA

ADC Characterization Data to Support IND Preparation

Key quality attributes—including drug loading, DAR distribution, purity and antibody integrity—are assessed using complementary analytical methods to support ADC development and further regulatory documentation.

Quality attribute	Why it matters	Method used
Quality attribute Average DAR	Why it matters Influences payload delivery, potency and pharmacokinetic properties.	Method used HIC-HPLC, LC-MS
Quality attribute DAR distribution / homogeneity	Why it matters Helps assess conjugation consistency and product heterogeneity.	Method used HIC-HPLC
Quality attribute Aggregation / monomeric purity	Why it matters Evaluates aggregate levels, a potential quality and immunogenicity concern.	Method used SEC-HPLC
Quality attribute Antibody integrity	Why it matters Assesses the integrity of the antibody following conjugation.	Method used SDS-PAGE
Quality attribute Unconjugated antibody (DAR 0)	Why it matters Quantifies antibody without payload, which may compete for target binding.	Method used HIC-HPLC, LC-MS

WORK WITH PROTEOGENIX

Looking for an ADC Conjugation Company?

From feasibility to site-specific conjugation and analytical characterization, ProteoGenix builds a development strategy around your antibody, payload and target DAR.

One scientific contact from scoping to delivery
Proprietary Click chemistry on native antibodies
Direct licensing, no third-party royalty stacking

Discuss Your ADC Project →

Antibody discovery & production

Generate or produce the antibody you want to conjugate.
ADC conjugation

Feasibility, site-specific conjugation and characterization.
Cell line development

Stable, high-yield cell lines for your lead antibody.
CDMO transfer

Transfer to an external CDMO partner for clinical-grade production.

5 ADCsAdvanced to clinical trials

Clinical Relevance

From Conjugation Technology to Clinical Development

Five ADC candidates developed using this conjugation technology have progressed to clinical trials, demonstrating its application beyond early-stage research.

SCIENTIFIC PUBLICATIONS

Research Supporting Our ADC Conjugation Technology

¹⁶¹Tb Radioimmunotherapy as a Treatment for CD30-Positive Lymphomas

Elisa Rioja-Blanco, Yara Banz, Christoph Schlapbach, Urban Novak, Tanja Chiorazzo, Nicole L. Bertschi, Peter Bernhardt, Pascal V. Grundler, Nicholas P. van der Meulen, Michal Grzmil, Roger Schibli, Martin Behe

Journal of Nuclear Medicine Jun 2025, 66 (6) 909-915; DOI: 10.2967/jnumed.124.268805

Read the publication

ADC Development: Frequently Asked Questions

ProteoGenix offers three antibody-drug conjugation approaches: site-specific Click chemistry, enzymatic conjugation, and random conjugation.

Our proprietary cysteine rebridging technology enables site-specific conjugation of compatible native antibodies without prior engineering, with controlled drug-to-antibody ratios (DAR). Enzymatic conjugation provides defined attachment sites, while random conjugation can be suitable for early-stage research and feasibility studies.

The most appropriate method depends on your antibody, payload, target DAR, and development objectives.
Yes. Our proprietary cysteine rebridging Click chemistry can enable site-specific conjugation of suitable native antibodies without introducing engineered conjugation sites.

Compatibility depends on the antibody’s structure and the selected linker-payload combination. We begin with a feasibility assessment to evaluate the conjugation strategy before proceeding to larger-scale production.
Our proprietary Click chemistry platform can target DAR 1, 2, or 4, depending on the conjugation strategy and molecular requirements.

The resulting DAR distribution is assessed using analytical methods such as HIC-HPLC and mass spectrometry. The achievable DAR profile depends on the antibody, payload, and conjugation conditions.
For the standard workflow, ProteoGenix requests approximately 2.5 mg of purified antibody for feasibility testing and 10 mg for full-scale conjugation.

Input material requirements, including concentration and purity, are reviewed before starting the project. If you do not have sufficient antibody material, we can also support recombinant antibody production.
ProteoGenix can evaluate customer-supplied payloads and linkers for compatibility with the selected conjugation technology.

Our conjugation capabilities cover different payload types, including cytotoxic drugs, nucleic acids, and fluorophores. Cleavable, non-cleavable, and custom linker strategies can be considered according to the project.

Payload and linker compatibility is confirmed during the feasibility assessment.
Our ADC conjugation service starts from 3 weeks, depending on the project requirements.

The workflow includes an initial feasibility study, typically lasting 1–2 weeks, followed by conjugation, purification, and analytical characterization. The overall timeline depends on antibody compatibility, payload availability, required quantities, and the selected analytical package.
ProteoGenix provides purified ADC material together with analytical data relevant to the selected conjugation strategy.

Characterization can include:
- Drug-to-antibody ratio (DAR) and DAR distribution
- Purity and aggregation assessment
- Antibody integrity
- Unconjugated antibody content
- Conjugation-related analytical data
Methods include HIC-HPLC, SEC-HPLC, SDS-PAGE, and mass spectrometry. The standard conjugation package described on this page includes 5 mg of purified ADC material, with the final deliverables confirmed during project scoping.
Yes. ProteoGenix can support your project from antibody discovery and recombinant production through optimization and ADC conjugation.

If your antibody requires further development, our complementary services include:
- Affinity maturation to improve target binding.
- Antibody humanization to reduce non-human sequence content while aiming to preserve binding properties.
- Antibody developability assessment to evaluate properties such as stability, aggregation, and manufacturability.
- Recombinant antibody production to generate material for conjugation and downstream studies.
Our team can help identify which development steps are relevant before starting your ADC conjugation project.
IP and licensing conditions depend on the conjugation technology and the intended use of the resulting ADC.

ProteoGenix offers a proprietary Click chemistry platform with direct licensing arrangements. Research-stage services and potential clinical or commercial applications may involve different contractual conditions.

Our team can clarify the applicable IP and licensing terms during project evaluation.

LET’S DISCUSS YOUR PROJECT

Ready to Develop Your ADC?

Whether you already have a purified antibody or need help defining the conjugation strategy, start with a technical discussion.

Custom antibody conjugation strategies
Site-specific Click chemistry
Purification and analytical characterization

? Not sure where to start?

Already have a purified antibody or a payload in mind? Tell us what you have and what you want to achieve. Our team will help assess feasibility and define the appropriate conjugation approach.

Antibody Drug Conjugate (ADC) Services

ADC Conjugation: Speed Meets Precision