Antibody-drug conjugate access landscape: ADC coverage and pipeline watch

The FDA has approved 14 antibody-drug conjugates (ADCs) as of early 2026, with global ADC sales projected to exceed $14 billion in 2026 and reach $34.8 billion by 2035. Over 100 ADCs are in clinical development, and the class now spans hematologic malignancies and solid tumors across more than a dozen targets. This access landscape maps every FDA-approved ADC (plus one China-approved ADC relevant to the global pipeline), summarizes payer coverage patterns, identifies prior authorization friction points, and flags the pipeline targets most likely to drive new formulary decisions.

All 14 FDA-approved ADCs (plus 1 China-approved)

Sources: FDA-approved prescribing information; Cell (2026) review of ADC clinical progress; BioChemPEG ADC compilation; NIH/PMC antibodies-to-watch review.

Formulary and payer coverage patterns

Payer classification

Payers uniformly classify ADCs under antineoplastic specialty tiers. In a 2026 Apple Health (Medicaid) preferred drug list, all approved ADCs are listed as non-preferred with prior authorization required (coded "NC" or "P PA"):

• Adcetris, Besponsa, Elahere, Enhertu, Kadcyla, Mylotarg, Padcev, Polivy, Tivdak, Trodelvy: all classified as non-preferred specialty requiring PA

• Zynlonta: non-preferred specialty requiring PA

This pattern is consistent across commercial and Medicaid formularies. No approved ADC is available without prior authorization.

Prior authorization criteria

Premera's 2026 medical policy on ADCs (policy 5.01.582, effective January 2026) provides a representative framework. Key patterns:

Step therapy and line-of-therapy requirements:

• Most ADCs require progression on or intolerance to prior standard therapies

• Enhertu in HER2+ breast cancer: requires prior anti-HER2-based regimen in the metastatic setting, or recurrence during/within 6 months of adjuvant therapy

• Trodelvy in TNBC: requires two or more prior therapies, at least one for metastatic disease

• Padcev in urothelial cancer: updated 2026 criteria now include combination with pembrolizumab as an approved regimen

Biomarker requirements:

• Enhertu in HER2-low breast cancer: requires IHC 1+ or IHC 2+/ISH− confirmation

• Elahere: requires FRα-positive tumor confirmed by an FDA-approved test

• Emrelis: requires c-Met protein overexpression (≥50% of tumor cells with 3+ staining) by FDA-approved test

• Trodelvy: no specific biomarker required (TROP2 expression is not used for patient selection)

Site-of-care requirements:

• Most ADCs are administered in hospital outpatient or infusion center settings

• Medical benefit (not pharmacy benefit) is the dominant coverage pathway

• Buy-and-bill reimbursement under Medicare Part B applies to physician-administered ADCs

Market size and spend implications

The global ADC market is estimated at $14.09 billion in 2026, growing at a CAGR of 10.61% through 2035. Key spend drivers:

• Enhertu: projected to remain the highest-selling ADC at approximately $6.2 billion globally, driven by multiple breast cancer indications (HER2+, HER2-low, HER2-ultralow), gastric cancer, and NSCLC

• Padcev: second-highest projected at approximately $3.5 billion, supported by the combination with pembrolizumab as first-line treatment for advanced urothelial cancer

• Trodelvy: growing across TNBC, HR+/HER2− breast cancer, and urothelial cancer

For payers, the expansion of ADC indications into earlier lines of therapy and broader patient populations (e.g., HER2-low breast cancer) represents the most significant budget impact. Each new indication can multiply the eligible patient population by 3–5×.

Emerging pipeline targets

The next wave of ADC development targets antigens with no approved predecessors, in tumor types underserved by first-generation ADCs. As of early 2026:

BMS and AbbVie are also developing bispecific ADCs — a next-generation format that targets two antigens simultaneously. AbbVie's ABBV-969 (PSMA/STEAP1 bispecific ADC) showed a 45% confirmed ORR in mCRPC in first-in-human data being presented at ASCO 2026.

Access implication: New targets and bispecific formats will require new companion diagnostics and expanded biomarker testing panels. Payers should anticipate PA criteria requiring dual-antigen confirmation for bispecific ADCs.

Key access challenges

1. Biomarker testing bottlenecks. HER2-low, FRα, c-Met, and future targets (B7-H3, DLL3) all require specific IHC or molecular testing. Turnaround time and test availability affect time-to-treatment.

2. Cross-label PA complexity. Enhertu now has five distinct indications across breast, gastric, and lung cancers. Payer PA criteria must specify the correct indication and line of therapy.

3. Combination therapy costs. Padcev + pembrolizumab and Polivy-based regimens combine ADC cost with checkpoint inhibitor cost. Payers must adjudicate both components.

4. Accelerated approval obligations. Emrelis received accelerated approval, and others (Blenrep) were withdrawn and reapproved. Payers should track confirmatory trial progress.

5. Oral ADC development. No oral ADC has been approved, but several programs are in preclinical stages. If any reach the clinic, they would shift coverage from medical benefit to pharmacy benefit.

What access teams should monitor

1. ASCO 2026 ADC data. Multiple ADC programs will present at ASCO (May 29–June 2), including AbbVie's ABBV-969, BMS's iza-bren, and Pfizer's sigvotatug vedotin. Monitor for practice-changing data.

2. Enhertu label expansions. Daiichi/AstraZeneca continue to pursue new indications. Any expansion into adjuvant or neoadjuvant settings would significantly increase eligible patient populations.

3. Trodelvy vs. Datroway competition. Both target TROP2 in HR+/HER2− breast cancer. Payers will need head-to-head or cross-trial comparison frameworks.

4. CMS prior authorization interoperability rule. CMS's 2026 proposed rule extends electronic PA requirements to drugs covered under medical benefit, including ADCs. Implementation is proposed for October 2027.

5. ADC discontinuation rate. As of March 2026, 89 ADC programs have been discontinued. Track active programs and avoid building coverage policies around candidates likely to fail.

Sources

• Cell (2026): "Navigating the clinical progress of antibody-drug conjugates": https://www.cell.com/cell/fulltext/S0092-8674(26)00451-4

• NIH/PMC: "Antibodies to watch in 2026": https://pmc.ncbi.nlm.nih.gov/articles/PMC12826703

• BioChemPEG: "FDA Approved Antibody-Drug Conjugates (ADCs) By 2026": https://www.biochempeg.com/article/74.html

• PatSnap: "Four Antibody-Drug Conjugates Designated in February 2026": https://www.patsnap.com/resources/blog/articles/adc-pipeline-february-2026

• Premera medical policy 5.01.582 (ADCs, effective January 2026): https://www.premera.com/medicalpolicies/5.01.582.pdf

• Mass General Brigham Health Plan PA policy for breast cancer ADCs (effective January 2026): https://resources.massgeneralbrighamhealthplan.org/pharmacy/PharmacyPolicies/MedicaidPolicies/BreastCancerTherapy_DatrowayEnhertuHalavenKadcylaMargenzaPerjetaPhesgoTrodelvy_PA_MH_MB_01.01.26.pdf

• CMS: "2026 CMS Interoperability Standards and Prior Authorization for Drugs Proposed Rule": https://www.cms.gov/newsroom/fact-sheets/2026-cms-interoperability-standards-prior-authorization-drugs-proposed-rule

• Precedence Research: "Antibody Drug Conjugates Market Size to Hit USD 34.80 Bn by 2035": https://www.precedenceresearch.com/antibody-drug-conjugates-market

• NJBio: "Recent Advances in ADCs" (March 2026 data): https://njbio.com/antibody-drug-conjugates

• ClinicalTrials.gov: https://clinicaltrials.gov