An antibody, a linker and a payload
An ADC joins an antibody to a cell-killing payload through a linker. The antibody helps deliver the drug to cells bearing its target. Target expression, internalization, linker behavior and payload sensitivity all affect activity. Some payloads can also act on nearby cells.
This is targeted delivery, not an assurance that healthy tissue is spared completely. ADCs can cause substantial systemic toxicity, and their side-effect profiles differ.
| Part | Why it matters |
|---|---|
| Antibody | Recognizes a target; target name alone does not define eligibility. |
| Linker | Influences where and how the payload is released. |
| Payload | Determines the cell-killing mechanism and part of the toxicity profile. |
Source [1]
Which test actually selects treatment?
HER2-directed ADCs can require a defined immunohistochemistry or amplification result. For other ADCs, the approved cancer type and treatment history may be more important than a mandatory target-expression test. Do not apply one product’s cutoff to another.
A TROP2 ADC, an EGFR ADC and an EGFR×HER3 bispecific ADC are distinct products. Similarly, two ADCs aimed at the same target may have different payloads, evidence and approved uses.
Bring the assay, not just “positive”
A report may describe gene amplification, mutation or protein staining; these are not interchangeable. Ask whether the proposed ADC requires a specific test and whether the available specimen meets that requirement. A target can be biologically interesting without being a validated selection test for that drug.
Source [1]
Global treatment frontiers
ADC development is moving beyond adding another target to asking whether a drug can improve the next treatment after resistance. OptiTROP-Lung04 compared sacituzumab tirumotecan with platinum–pemetrexed after EGFR-TKI treatment in advanced EGFR-mutated NSCLC and demonstrated progression-free and overall-survival benefits. Its Chinese approval brings this evidence into a defined clinical pathway while broader international development continues.
Other platforms address different gaps: iza-bren binds EGFR and HER3, while MRG003 delivers a microtubule-disrupting payload through EGFR. Their roles in previously treated nasopharyngeal or esophageal cancer broaden the ADC landscape beyond established breast-cancer applications. Target, payload, previous ADC exposure and trial comparator are more informative than simply choosing the newest product.
Where an ADC fits in the sequence
ADCs are used in both later and, for selected indications, earlier treatment settings. After a previous ADC, choosing another depends on progression pattern, remaining organ reserve, target biology and possible payload cross-resistance. Evidence for sequential ADCs is not equally mature across cancers.
Ask whether the supporting trial compared the ADC with a relevant current treatment and whether it improved survival, disease control or both. Results from different trials should not be ranked as though the patients were identical.
After another ADC, compare more than the target
Bring the exact previous drug, best response, reason for stopping and unresolved toxicity. Changing the antibody target may still leave a similar payload. Conversely, a different payload may have its own limiting toxicity. The relevant evidence is the proposed sequence in similar patients, not the response rate from an unrelated first-use trial.
Source [5]
Monitoring is specific to the product
Blood-count suppression, nausea, mouth inflammation and fatigue are common concerns with several ADCs. Depending on the payload, lung inflammation, neuropathy or eye toxicity may be especially important. Baseline symptoms and prior toxicity should be documented. New cough, fever or breathlessness needs early review; it should not automatically be attributed to the cancer.
A practical checklist for each review
Supportive care and treatment interruption rules are product-specific. Do not wait for symptoms to become severe before reporting them.
- New cough, breathlessness or fever, including when it began relative to treatment.
- Mouth soreness, difficulty eating, diarrhea and the ability to maintain fluids.
- Numbness, vision changes or difficulty with daily activities; these may affect the next dose.
Estimated total treatment cost
US$15,000–113,000 across the ADC treatments listed below. The medicine and treatment plan determine the relevant range; these medicines are used in different clinical settings.
| Treatment plan | Estimated total cost |
|---|---|
| Disitamab vedotin (RC48) | US$15,000–51,000 |
| Trastuzumab deruxtecan (T-DXd) | US$17,000–54,000 |
| Sacituzumab tirumotecan (SKB264 / sac-TMT) | US$16,000–52,000 |
| Becotatug vedotin (MRG003) | US$28,000–76,000 |
| Izalontamab brengitecan (iza-bren) | US$40,000–113,000 |
What’s included
These are estimates of total medical treatment costs for the listed treatment plans. In addition to the named medicines, they include specialist consultations and assessment, pretreatment tests, routine laboratory and imaging follow-up as needed, treatment administration and nursing where applicable, necessary hospitalization and monitoring, and routine supportive care. Travel and accommodation are not included.
Your individual treatment costs
Many ongoing ADC treatments do not have a fixed treatment duration. Costs accumulate with the infusions received and vary with the dose, combination therapies and care needs. These ranges relate to the listed ADC treatments; additional anticancer medicines require a separate estimate. This range is indicative only; your individual costs may fall outside it. Contact us for a personalized cost estimate based on your medical needs and specialist assessment.
Evidence & sources
Prepared by Chirona’s content team from the sources below. This guide supports a discussion with your treating team; it does not determine an individual treatment plan.