MYLAN RECEIVES TENTATIVE APPROVAL FOR FIRST GENERIC CARDIZEM (DILTIAZEM)

MYLAN RECEIVES TENTATIVE APPROVAL FOR FIRST GENERIC CARDIZEM (DILTIAZEM) on March 16. The generic firm gained approvable status for all four dosage forms (30, 60, 90 and 120 mg) of the Marion Merrell Dow calcium channel blocker. The approval is designated as tentative because Mylan may not begin shipping the product until Cardizem's marketing exclusivity expires on Nov. 5. Marion Merrell Dow has been busy with efforts to minimize the impact of patent expiration on the blockbuster product. Sales for the Cardizem family of products were $912 mil. in 1991. MMD received approvals late in 1991 for two Cardizem line extensions, that it hopes will help stave off generic competition -- Cardizem CD, a once-daily formulation, and Cardizem IV, for use in hospitals. Exclusivity for Cardizem CD would run out in December 1994. Since the approval of Cardizem CD, MMD has engaged in a campaign to encourage physicians to switch their patients from the older Cardizem SR to the once-daily regimen. Most patients receiving Cardizem already use the sustained-release form. MMD has placed ads in consumer magazines to inform current Cardizem SR users of the availability of Cardizem CD, noting that it may be more economical and easier to take. Another effort to stymy generic competition is being made by Rhone-Poulenc Rorer, which is aiming to carve out a niche between Cardizem CD and immediate-release generics by establishing a sustained-release diltiazem brand called Dilacor at a discount to Cardizem CD ("The Pink Sheet" Feb. 17, p. 4). RPR filed a full NDA for Dilacor in April 1990 and is hoping for approval by the end of 1992.