FDA's ORAL VERAPAMIL ANDA APPROVALS ON EVE OF EXCLUSIVITY EXPIRATION PIT FIVE GENERIC PRODUCTS v. CALAN, ISOPTIN; INDERAL, REGLAN INDICATIONS NO LONGER EXCLUSIVE
FDA gave prospective ANDA approvals for oral verapamil to Barr, Danbury, and Purepac, on Sept. 23 -- the day before market exclusivity for oral Calan (Searle) and Isoptin (Knoll) expired. The three generic manufacturers join Parke-Davis and Rugby as the first companies to bring generic oral verapamil to the market following the expiration of the two year exclusivity period granted to new dosage forms/labeling approved during the 1982-1984 transition period provided by the Waxman/Hatch act. Both Parke-Davis and Rugby initiated product launches on Sept. 25, the day after the two year anniversary of the signing of the Waxman/Hatch act. The two firms had earlier received prospective ANDA approvals for verapamil 80 mg and 120 mg tabs -- Parke-Davis on Aug. 20 and Rugby's Chelsea division on Sept. 17. The two year Waxman/Hatch anniversary throws open to all competitors any indication which had been exclusively marketed under the provisions of the law. Ayerst, for example, is losing the last proprietary indication for Inderal. Other products that had been affected by the exclusivity expiration include: haloperidol, nalbuphine, naloxone, cyclophosphamide, and metoclopramide. Co-marketed by Searle and Knoll, oral verapamil was approved by FDA in March 1982, seventh months after the approval of the I.V. form of the calcium channel blocker. As a new dosage form approved during the Jan. 1, 1982 to Sept. 24, 1984 window period granted by the ANDA/patent restoration law, oral verapamil received market exclusivity until Sept. 24, 1986 despite the expiration of the product patent prior to that date. Rugby's oral verapamil launch marks the second time in a little over a year that the generic firm has been among the first to get approval for a major cardiovascular product. In July 1985, Rugby and Lederle were the first companies to launch generic propranolol (Inderal). Rugby markets its products through its 100-person detail force and a large telemarketing group. By the end of the year, oral verapamil will benefit from a separate generic drugs marketing organization at Warner-Lambert, the company recently indicated. The generic business will be lifted from Parke-Davis and set up as a separate division to be called Warner-Chilcott. Warner-Lambert is at least the second research-based drug manufacturer with a generic drug business to recently reorganize that business to give it a higher profile. In August, Squibb announced that it had restructured its generic drug and consumer products into the new SquibbMark division. Like Rugby, Parke-Davis has also had some success in receiving first approvals for generic drugs with significant sales potential. Parke-Davis joined Mylan and Zenith in Sept. 1985 in receiving the first approvals for generic diazepam (Valium). In all, Parke-Davis had nine generic products approved via the ANDA route in 1985, including erythromycin, doxycycline and procainamide. Estimates currently put the size of Warner-Lambert's generic business in the $40 mil. to $50 mil. range in annual sales. Leucovorin is another off-patent drug whose oral form is now losing exclusivity. Marketed both by Burroughs Wellcome, under the trade name Wellcovorin, and Lederle, oral leucovorin was the subject of a lawsuit between the two companies when FDA's generic drug division approved Lederle's product in January 1985 via a 5C NDA ("The Pink Sheet" March 7, T&G 2). Burroughs Wellcome had sought market exclusivity through Sept. 24. However, in March, a Raleigh, North Carolina federal court ruled on behalf of Lederle. Other dosage forms of brand name products will soon be available as generics. Par, Parke-Davis, Barr, and Roxane have prospective approvals to market 60 mg propranolol, while Roxane holds an approved ANDA for 90 mg propranolol. Searle holds an ANDA for 20 mg haloperidol (McNeil's Haldol). Further, FDA has already granted prospective approvals to Elkins-Sinn and LyphoMed for formerly exclusive dosage forms of cyclophosphamide. LyphoMed also has an approval for 20 mg/ml nalbuphine. In addition to losing exclusive marketing rights to 60 mg and 90 mg dosage forms of propranolol, Ayerst no longer has the exclusive right to include a post-myocardial infarction indication in Inderal labeling. The firm has used its post-MI labeling as leverage against pharmacists' substitution of Inderal with generic propranolol. Controlled release propranolol is also no longer covered by exclusivity. Robins Reglan (metoclopramide) is another product that is losing exclusive indications. Although Reglan has faced generic competition since July 1985, the brand name drug has carried several indications not carried by the generics that were used by Robins to differentiate Reglan. The I.V. form of Reglan has carried exclusive labeling for chemotherapy- and cisplatiin-induced emesis, while the oral form has carried exclusive labeling for gastroesophageal reflux disase. Chart omitted.
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