Merck may not have broken any antitrust laws with a discount scheme for its rheumatoid arthritis drug Remicade—but not for lack of trying, British regulators concluded.

The UK’s Competition and Markets Authority has decided not to pursue antitrust charges over a discount program Merck put together that offered a sliding scale of discounts for Remicade (infliximab)—the more drug bought, the deeper the discount.

In announcing their decision, the regulators said the “discount scheme was designed to delay or reduce competition,” but it just didn’t work.

Merck misjudged the attitudes of National Health Service officials toward competing biosimilars, and the “relative strength of the financial incentive” offered by the discounts wasn’t as strong as the pharma company had guessed, CMA found.