The European Commission said the pharmaceutical firm "misused the patent system to artificially extend patent protection" for its blockbuster MS drug Copaxone, whose active ingredient is glatiramer acetate.
To do that, Teva conducted a "disparagement campaign" against Synthon, the only other company with an authorised drug in Europe containing glatiramer acetate, the Commission said in a statement.
Teva "spread information contradicted by health authorities' findings, seeking to sow doubt on the safety, efficacy and therapeutic equivalence of the rival product," the EU Commission said.
It added that Teva officials had targeted doctors and groups involved in drug pricing and reimbursement, "with the target of slowing down or blocking its competitor's entry" into several countries.
Teva set to appeal EU Commission decision
In a statement, Teva said it disagreed with the EU Commission's decision, which it described as "based on legal theories ... that are extreme, untested, and factually unsupported". It said it intended to appeal the decision and that it had supported the MS community since 1996.
The EU Commission said Teva's actions may have prevented significant savings by countries across Europe, with other versions of the drug possibly 80% cheaper than Copaxone. Teva will have to pay a fine of €462.6m and refrain from similar practices in the future, it said.
Last year, Teva was ordered to pay $225m (€207m) to settle price fixing charges in the United States related to sales of a cholesterol-lowering drug.
The US Justice Department said the agreement also required Teva to divest its business making and selling the drug pravastatin, a generic version of the brand-name medicine Pravachol.