The issue focused on the half-life of the drug, with the company saying in a statement that the half-life of the drug is "exceeding 2.5 years, and is not expected to be lower."

Gilead's position is that the half-life of the drug is "exceeding 2.5 years, and is not expected to be lower."

Gilead's position is that the half-life of the drug is "exceeding 2.5