GSK to buy US cancer biotech IDRx for up to $1.15 billion

By Ashleigh Furlong

GSK Plc agreed to buy US biotech IDRx for as much as $1.15 billion to gain new cancer medicines.

The UK drugmaker will pay $1 billion upfront for IDRx, whose lead drug for gastrointestinal tumors shows potential against mutations that currently leave patients with few treatment options, GSK said Monday.

IDRx’s experimental medicine has shown activity against mutations that drive most of the cases of gastrointestinal stromal tumors and could offer the first significant treatment advance in the field in almost 20 years, the companies said.

GSK shares were little changed in early London trading, as they have been since the start of the year.

Investors are concerned about GSK’s pipeline and recent lower-than-expected sales of its RSV and shingles vaccines. The bright light has been some unexpected successes in cancer. Typically a smaller player in this space, GSK has been slowly working to expand its oncology capabilities.

The company aims to bring previously withdrawn blood cancer drug Blenrep back to market and has seen strong sales of another cancer medicine, called Ojjaara.

The GSK announcement, on the day the annual JP Morgan investor conference kicks off, confirms earlier reports about the transaction. IDRx may get an additional $150 million in success-based milestone payments.

Gastrointestinal stromal tumors are a type of cancer that begins in the digestive system and can cause vomiting, fatigue and abdominal pain.

IDRx launched in 2022 with license agreements with Germany’s Merck KGaA and Blueprint Medicines. IDRx’s leading medicine was part of the Merck deal. Under Monday’s agreement, GSK will have to pay success-based milestone payments and tiered royalties owed to Merck.