The milestone payment triggers from the initiation of a Phase 1 clinical trial of ISIS-TTRRx, an antisense drug, by Isis Pharma to treat transthyretin amyloidosis.
The agreement allows Isis to get an upfront payment of $35m from GSK with licensing fees amd milestone payments totaling nearly $1.5bn.
Isis Pharma chief operating officer Lynne Parshall said in a little over a year, they have begun clinical development on the first drug in this collaboration, and they look forward to moving additional drugs from this collaboration into our pipeline.
"Already we have earned $48m in payments from GSK, including $8m this year and anticipate making significant progress in our drugs to treat severe and rare diseases, such as transthyretin amyloidosis," Parshall said.