ADC CDMOs — Bioconjugation, HPAPI & GMP Rankings

CDMOs tracked

Fully scored

With FDA records

FDA inspections

EMA/MHRA GMP certs

Warning letters

Antibody-drug conjugates pair a targeting antibody with a cytotoxic payload via a chemical linker — a three-component process that crosses biologics, small-molecule, and HPAPI (high-potency API) disciplines. Manufacturing demands purpose-built containment (typically OEB-5), wet-chemistry linker-payload synthesis, and validated bioconjugation under GMP.

Selecting an ADC CDMO turns on commercial bioconjugation track record, containment level, the linker / payload chemistries already in their book of business (vc, mc, glucuronide; MMAE, MMAF, DM1, DM4, Dxd, calicheamicin, PBDs, etc.), drug-substance + drug-product capability, and clean FDA + EMA/MHRA inspections. The rankings below score each CDMO on FDA inspections, GMP certification, clinical activity, and capacity.

FDA inspection outcomes across these CDMOs: 8 NAI (no action), 17 VAI (voluntary action), 1 OAI (official action). Leading inspection & GMP sites: United States (21), UNITED KINGDOM (21), Denmark (18), Germany (10), UNITED STATES (8).

Last updated 2026-06-24. Sourced from FDA, EMA EudraGMDP, MHRA GMDP, and ClinicalTrials.gov.

#	CDMO	Signal Score	Quality	FDA · GMP	Capacity	Programs
1	CR Charles River Laboratories Newbury Park, CA · Memphis, TN · Keele, UK · Rockville, MD	91.7	98.7	7 insp · 11 GMP	Limited	0 programs
2	WB2 WuXi Biologics Shanghai, CN · Wuxi, CN	83.7	100.0	0 insp · 4 GMP	—	0 programs
3	PR Piramal Pharma Solutions Lexington, KY · Riverview, MI · Ahmedabad, IN	83.6	95.7	5 insp · 13 GMP	—	0 programs
4	AG AGC Biologics Longmont, CO · Milan, IT · Copenhagen, DK · Chiba, JP	80.6	99.9	1 insp · 23 GMP	Available	2 programs
5	Lonza Basel, Switzerland	78.2	95.1	2 insp · 8 GMP	—	1 programs
6	Catalent Somerset, NJ (now operating under Novo Holdings, HQ effectively Bagsværd, Denmark)	76.5	79.3	10 insp · 32 GMP	—	0 programs
7	CA Catalent (Novo Holdings) Harmans, MD · Gosselies, BE	75.1	79.3	1 insp · 0 GMP	Available	0 programs
8	SB Samsung Biologics Incheon, South Korea	68.5	—	—	—	0 programs
—	Abzena San Diego, CA	Profiled	—	—	—	0 programs
—	Icosagen Tartu, Estonia	Profiled	—	—	—	0 programs
—	WuXi XDC Shanghai, China	Profiled	—	—	—	0 programs
—	Altruist Biologics Suzhou, China	Profiled	—	—	—	0 programs
—	Olon Group Rodano (Milan), Italy	Profiled	—	—	—	0 programs
—	Olon Rodano (Milan), Italy	Profiled	—	—	—	0 programs
—	Fermion (Orion Group) Espoo, Finland	Profiled	—	—	—	0 programs
—	Meiji Seika Pharmatech Co., Ltd. Tokyo, Japan	Profiled	—	—	—	0 programs
—	PCI Pharma Services Philadelphia, PA	Profiled	—	—	—	0 programs

How we score CDMOs →

What to evaluate in a ADC (Antibody-Drug Conjugate) CDMO

HPAPI containment

Look for OEB-5 (sub-microgram occupational exposure band) suites for handling cytotoxic payloads end-to-end. Containment maturity is the floor for credible commercial ADC work.

Linker-payload chemistry on file

Match the CDMO's payload + linker experience to your program. MMAE / vc-MMAE is the most common; PBDs, calicheamicin, Dxd-class topoI inhibitors, and TLR agonists each carry distinct handling and analytical demands.

Commercial bioconjugation track record

Has the CDMO conjugated a commercially-approved ADC? Track record on Polivy, Padcev, Trodelvy, Enhertu, Tivdak, Elahere, Adcetris, Mylotarg, Besponsa, Lumoxiti, Blenrep, etc. is a strong qualifying signal.

Integrated DS + DP

Bioconjugation produces ADC drug substance; you'll also need sterile fill-finish for drug product. Confirm whether the CDMO covers both or partners — both routes work, but integrated is faster on transfer.

Regulatory track record

Cross-check FDA 483 history and EMA/MHRA GMP coverage — both shown above and on each profile.

ADC (Antibody-Drug Conjugate) CDMOs — Frequently Asked Questions

Who are the top ADC (Antibody-Drug Conjugate) CDMOs?

By CDMO Signal's independent Signal Score, the top-ranked ADC (Antibody-Drug Conjugate) CDMOs include Charles River Laboratories, WuXi Biologics, Piramal Pharma Solutions. See the full ranked table above — scored on FDA, clinical, financial, and capacity data.

How many ADC (Antibody-Drug Conjugate) CDMOs have FDA inspection records?

CDMO Signal tracks 6 ADC (Antibody-Drug Conjugate) CDMOs with FDA inspection records and 91 EMA/MHRA GMP certificates across the group.

What's the difference between an ADC CDMO and a biologics CDMO?

A biologics CDMO makes the naked antibody (drug substance). An ADC CDMO additionally handles the cytotoxic payload synthesis and the bioconjugation step under HPAPI containment. Some large CDMOs (Lonza, Catalent) do both; others specialize in conjugation only and source the antibody from a biologics partner.

Which CDMOs have made commercially-approved ADCs?

Several CDMOs have commercial ADC track records. The rankings above show our scored ADC players — Lonza (Polivy, Padcev), Catalent (multi-program commercial conjugation), Piramal, AGC Biologics, Samsung Biologics, WuXi Biologics, Charles River — with FDA inspection and GMP detail per profile.

What HPAPI containment level should an ADC CDMO have?

OEB-5 (sub-microgram per cubic meter occupational exposure band) is the standard floor for handling MMAE, MMAF, DM1, DM4, Dxd, PBDs, and calicheamicin-class payloads. Some legacy payloads can run in OEB-4 but commercial work is OEB-5.

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