A key innovation in Antibody-Drug Conjugates (ADCs) is the 'tandem cleave' linker. This technology requires two separate events—one in the tumor microenvironment and another after internalization—to release the payload, improving stability and reducing systemic toxicity.

A key barrier to complex peptide-antibody drugs is manufacturing (CMC). Current methods require separate synthesis and conjugation steps. A fully genetically encoded system—where the entire hybrid molecule is produced in a single cell line—would dramatically lower the barrier to entry and simplify manufacturing, unlocking new drug designs.

When sequencing antibody-drug conjugates, clinical experience suggests that resistance to the chemotherapy payload is a primary driver of failure. Therefore, oncologists tend to avoid using another ADC with the same payload consecutively, preferring to switch both target and payload if possible.

The discovery-based model of finding highly impactful single targets like HER2 or PD-1 is becoming unsustainable as the low-hanging fruit is picked. The field must shift toward an engineering-first approach, designing complex, multi-functional therapeutics to achieve specific clinical objectives, much like high-tech fields.

To mitigate the severe toxicity of promising pan-RAS inhibitors, companies are adopting antibody-drug conjugate (ADC) technology. This marks a strategic expansion for ADCs, moving beyond traditional cytotoxic chemotherapy payloads to delivering highly specific targeted therapies, aiming to improve the therapeutic window of potent new drug classes.

The primary reason Antibody-Drug Conjugates (ADCs) stop working is payload resistance, a shift from the traditional belief that failure stems from tumors losing the target antigen. This insight drives development of multi-payload ADCs to overcome this resistance mechanism.

As biologics evolve into complex multi-specific and hybrid formats, the number of design parameters (valency, linkers, geometry) becomes too vast for experimental testing. AI and computational design are becoming essential not to replace scientists, but to judiciously sample the enormous design space and guide engineering efforts.

As multiple effective Antibody-Drug Conjugates (ADCs) become available, the primary clinical challenge is no longer *if* they work, but *how* to use them best. Key unanswered questions involve optimal sequencing, dosing for treatment versus maintenance, and overall length of therapy, mirroring issues already seen in breast cancer.

The BioCentury Grand Rounds conference agenda signals a shift in R&D focus. Progress isn't just about big biological concepts, but about mastering niche, highly technical problems like linker stability in ADCs, which are often the make-or-break elements for next-generation therapies.