HER2 Support Group Forums - View Single Post - circumstances under which lapatinib, not herceptin, might be the drug of choice

Lani · 05-11-2010, 08:49 AM

Bill i would interpret it as lapatinib is effective for her2 overexpressing tumors with or without p95, but herceptin is only effective in those without p95.(makes sense if you understand how lapatinib attacks the internal tyrosine kinase phosphorylation site, which doesn't depend on an extensive extracellular domain whereas herceptin's (many?) mechanism(s) of action are felt to revolve around sites on the extracellular domain which are not present on p95 shortened versions of the receptor

the test for p95 has not yet been made commercially available as far as i know

hope this helps

05-11-2010, 08:49 AM	#4
Lani Senior Member Join Date: Mar 2006 Posts: 4,783	Re: circumstances under which lapatinib, not herceptin, might be the drug of choice Bill i would interpret it as lapatinib is effective for her2 overexpressing tumors with or without p95, but herceptin is only effective in those without p95.(makes sense if you understand how lapatinib attacks the internal tyrosine kinase phosphorylation site, which doesn't depend on an extensive extracellular domain whereas herceptin's (many?) mechanism(s) of action are felt to revolve around sites on the extracellular domain which are not present on p95 shortened versions of the receptor the test for p95 has not yet been made commercially available as far as i know hope this helps