Best ADC (Antibody-Drug Conjugate) CDMOs in United States
· updated as new inspection, certificate, and trial data enters the platform
10
CDMOs tracked
4
Fully scored
5
With FDA records
51
FDA inspections
92
EMA/MHRA GMP certs
2
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: 19 NAI (no action), 30 VAI (voluntary action), 2 OAI (official action). Leading inspection & GMP sites: United States (37), Denmark (23), UNITED KINGDOM (22), Germany (14), Belgium (7).
Last updated 2026-10-31. Sourced from FDA, EMA EudraGMDP, MHRA GMDP, and ClinicalTrials.gov.
| # | CDMO | Signal Score | Quality | FDA · GMP | Capacity | Programs |
|---|---|---|---|---|---|---|
| 1 |
AG
AGC Biologics
Longmont, CO · Milan, IT · Copenhagen, DK · Chiba, JP
Hiring · 34 open roles
|
78.5 | 99.8 | 4 insp · 27 GMP | Available | 2 programs |
| 2 |
CR
Charles River Laboratories
Newbury Park, CA · Memphis, TN · Keele, UK · Rockville, MD
|
86.3 | 99.2 | 9 insp · 11 GMP | Limited | 0 programs |
| 3 |
PR
Piramal Pharma Solutions
Lexington, KY · Riverview, MI · Ahmedabad, IN
|
83.5 | 95.6 | 7 insp · 15 GMP | — | 0 programs |
| 4 |
Catalent
Tampa, FL
Hiring · 296 open roles
|
68.6 | 65.2 | 24 insp · 39 GMP | — | 0 programs |
| — |
Veranova
United States
|
Profiled | — | — | — | 0 programs |
| — |
Wheeler Bio
Oklahoma City, Oklahoma, USA
|
Profiled | — | — | — | 0 programs |
| — |
Gannet BioChem
Huntsville, Alabama, United States
|
Profiled | — | — | — | 0 programs |
| — |
GBI (Goodwin Biotechnology)
Plantation, Florida, USA
|
Profiled | — | — | — | 0 programs |
| — |
AbbVie Contract Manufacturing
North Chicago, Illinois, United States
|
Profiled | — | 7 insp · 0 GMP | — | 0 programs |
| — |
Pfanstiehl
Waukegan, Illinois, USA
|
Profiled | — | — | — | 0 programs |
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.
FDA jurisdiction — how the ranking scores US-based CDMOs
The Signal Score's Quality Compliance pillar (35% of the composite) is dominated by FDA inspection data for US-based CDMOs: Establishment Inspection Report classifications (NAI, VAI, OAI), Form 483 observation counts, and Warning Letter history. For a CDMO whose primary facility footprint is US, this pillar carries direct weight — an inspection on the site slated for a sponsor's program applies without translation. For CDMOs with mixed US + international facility footprint, the ranking reflects the composite regulatory posture; sponsors evaluating for a specific program should verify inspection history on the exact US site under consideration via that CDMO's profile page.
Which US CDMOs also cover EU and UK regulatory geographies?
Many top-tier US-based CDMOs maintain EU (EMA) and UK (MHRA) GMP certification for facilities used to supply EU and UK trials or commercial markets. The Signal Score's Quality Compliance pillar includes EMA + MHRA certificate density as a component — a US-headquartered CDMO with dense EU/UK certificates typically ranks higher on this pillar than a US-only competitor. Sponsors running dual-jurisdiction programs should cross-check the individual CDMO profile pages for specific certificate coverage; the Europe region ranking surfaces CDMOs that also appear in the European jurisdiction ranking, indicating multi-region regulatory posture.
How CDMO Signal identifies US manufacturing presence
Region attribution is derived from each CDMO's declared facility locations in our directory. A CDMO's facility list is validated against corporate filings, press releases, and — where public — the FDA facility registration (FEI number lookups). Region matching is done at the country level: a US state name or two-letter abbreviation in the facility list places the CDMO in the US region. CDMOs with US + international sites appear in every applicable region ranking, which reflects operational reality — such a CDMO is a legitimate candidate for programs in any of those jurisdictions.
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 AGC Biologics, Charles River Laboratories, 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 5 ADC (Antibody-Drug Conjugate) CDMOs with FDA inspection records and 92 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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