Pfizer Files Second Suit Against Warner-Lambert

The battle for Warner-Lambert Co. escalated Tuesday as Pfizer Inc. sued the drug maker for the second time in recent weeks in an effort to block Warner-Lambert’s merger with American Home Products Co.

Pfizer, which had countered with a higher bid for Warner-Lambert hours after the American Home deal was announced Nov. 4, filed a lawsuit last week against both Warner-Lambert and American Home, claiming their deal was illegal.

Tuesday’s suit, filed in Delaware Chancery Court, seeks to freeze out American Home and allow Pfizer to make a higher bid for Warner-Lambert.

Pfizer is alleging that Morris Plains, N.J.-based Warner-Lambert breached their contract to jointly market the blockbuster cholesterol-lowering drug Lipitor, saying the pact forbids either company from making a bid for the other. Pfizer said it purposely did not make a formal bid for Warner-Lambert because of that provision.