# DM1

Source: https://onco.cc/terms/dm1/  
OnCo record `dm1` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

DM1 is the maytansine-derived payload in Kadcyla: a tubulin blocker held by a non-cleavable linker, so it stays in the cell it entered.

## Summary

DM1 (mertansine) is released as a lysine-linker-payload catabolite after the antibody is degraded in the lysosome. That catabolite is charged and not membrane permeable, so trastuzumab emtansine has little bystander killing and needs high, uniform HER2 expression to work. Thrombocytopenia and raised liver enzymes are characteristic.

## Fields

- Kind: Term
- Last checked: 2026-09-09
- Also known as: mertansine; emtansine payload; mertansine, emtansine

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Mertansine
- Wikipedia: https://en.wikipedia.org/wiki/Mertansine

## Connected records

- terms: [Bystander effect (ADC)](https://onco.cc/terms/bystander-effect/), [Payload (ADC)](https://onco.cc/terms/payload/), [SMCC (thioether, non-cleavable)](https://onco.cc/terms/smcc/), [Tubulin inhibitor payloads](https://onco.cc/terms/tubulin-inhibitor-payloads/)
- technologies: [Antibody-drug conjugate (ADC)](https://onco.cc/technologies/adc/)
- drugs: [Trastuzumab emtansine](https://onco.cc/drugs/trastuzumab-emtansine/)
- pathways: [Mitosis & the spindle assembly checkpoint](https://onco.cc/pathways/mitotic-spindle-checkpoint/)

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JSON: https://onco.cc/api/v1/entities/dm1.json