Gilead Sciences (NASDAQ:GILD) has taken a step back from expanding its oncology department to bolster an already successful suite of antiviral products. On Thursday morning, the biotechnology giant from California entered a definitive agreement to acquire a German drug developer with a recently approved treatment for hepatitis delta virus (HDV).

Gilead Sciences will acquire MYR GmbH for around $1.4 billion, plus a potential milestone payment of up to $360 million. The purchase gives Gilead Sciences access to Hepcludex, a treatment for HDV that the European Medicines Agency granted conditional approval to this July.


Smiling pharmacist.

Image source: Getty Images.

Hepcludex is a first-in-class drug that blocks the virus responsible for HDV from entering liver cells. As the first and only available treatment for HDV, there's a good chance Gilead will be able to make this investment work out well for its shareholders.

You can't contract HDV unless you're already infected with hepatitis B virus (HBV), but there are still a combined 230,000 people with HBV/HDV co-infection in the U.S. and the EU. Worldwide, there are an estimated 12 million people with both infections, and Hepcludex will likely become a successful first treatment option for this large underserved population.

In a phase 2 trial, Hepcludex plus Viread wiped out HDV for 54 out of 90 patients. Viread on its own did the job for just one patient in a control group with 28 patients. In the first half of 2021, Gilead Sciences hopes to report successful results from an interim analysis of an ongoing phase 3 trial that will support upcoming applications for full approval of Hepcludex in the U.S. and EU. 

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