{"entity":{"id":"pbd-sg3199","kind":"term","name":"PBD dimer (SG3199 / tesirine)","aka":["pyrrolobenzodiazepine dimer","tesirine payload","SG3199"],"tldr":"The PBD dimer SG3199 crosslinks DNA in the minor groove without distorting it, so cells fail to detect the damage; it kills at picomolar concentrations, so ADCs need only a low drug-to-antibody ratio. Fluid retention, skin reactions and light sensitivity stopped several programmes; loncastuximab tesirine in large B-cell lymphoma is the approved example.","summary":"Pyrrolobenzodiazepine dimers bind in the minor groove and crosslink DNA without distorting it, so cells struggle to detect and repair the damage. Potency is picomolar, allowing low drug-to-antibody ratios. Fluid retention, skin reactions and light sensitivity are characteristic, and several PBD programmes were stopped for toxicity (for example vadastuximab talirine). Loncastuximab tesirine in large B-cell lymphoma is the successful case.","asOf":"2026-09-09","wikipedia":"https://en.wikipedia.org/wiki/Pyrrolobenzodiazepine","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Pyrrolobenzodiazepine"}],"tags":[],"related":[],"cancers":[],"sections":[],"technologies":["adc"],"targets":[],"drugs":["zynlonta"],"companies":[],"institutions":[],"pathways":[],"terms":["payload","pbd-dimer-payloads"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"ADC chemistry"},"route":"/terms/pbd-sg3199/","neighbours":{"technology":[{"id":"adc","kind":"technology","name":"Antibody-drug conjugate (ADC)","route":"/technologies/adc/"}],"drug":[{"id":"zynlonta","kind":"drug","name":"Loncastuximab tesirine","route":"/drugs/zynlonta/"}],"term":[{"id":"pbd-dimer-payloads","kind":"term","name":"DNA crosslinker payloads (PBD dimers)","route":"/terms/pbd-dimer-payloads/"},{"id":"payload","kind":"term","name":"Payload (ADC)","route":"/terms/payload/"},{"id":"val-ala","kind":"term","name":"Val-Ala dipeptide","route":"/terms/val-ala/"}]}}