The battle between generic and brand-name drug companies has escalated.

The latest litigation involves allegations that brand-name drug makers are refusing to sell product samples to generic-drug companies for bioequivalence testing—testing that determines whether the generic version of a drug is the exact replica of the brand-name version. Food and Drug Administration regulations require generic makers to complete such testing to prove that their drugs have the same biological effects as their brand-name counterparts. Generic-drug companies claim their brand-name rivals’ refusal to sell samples prevents them from completing the required testing and violates antitrust laws.

Accord Healthcare Inc. filed the latest such suit on Monday. It claims Acorda Therapeutics Inc. won’t sell samples of its brand-name drug Ampyra, which improves multiple sclerosis patients’ walking ability.

“Acorda’s refusal to sell samples of Ampyra at market prices to Accord Healthcare for bioequivalence testing is intended to, and will, thwart the entry to market of any competing products, thereby extending its monopoly power in the relevant market,” Accord said in its complaint.

In another case that’s currently underway in a New Jersey district court, two generic companies sued the brand-name company Actelion Pharmaceuticals Ltd. for not selling samples of the pulmonary hypertension drug Tracleer. In that case, the Federal Trade Commission has filed an amicus brief in support of the generic companies, saying Actelion’s refusal to sell the samples could be an antitrust violation.

Read Thomson Reuters for more about this pharmaceutical litigation trend.

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