MARION/SCHERING CARAFATE OTC USE AGAINST OVERINDULGENCE

MARION/SCHERING CARAFATE OTC USE AGAINST OVERINDULGENCE claim, as a prophylactic, may be the best approach for an Rx-to-OTC switch for the active ingredient, sucralfate, consultant Thomas Garvey, MD, told a May 9 conference sponsored by the Drug Information Association. Garvey, a gastroenterologist who used to be a top FDA medical officer and NDA reviewer, told the conference that he viewed an acute use of sucralfate OTC as problematic. "The reason is," Garvey said, "I need to see data that show me that sucralfate as an acute intervention is effective for symptoms of upper GI acid distress symptoms." FDA Office of Drug Evaluation I Director Robert Temple, MD, appeared to concur implicitly that a prophylactic use switch might be viewed more favorably by the agency. Answering a general question on FDA's receptiveness to OTC prevention claims, Temple said "in the GI area, prevention for overindulgence -- which is when we plan to do something that we shouldn't -- is one kind of problem, whereas chronic therapy to prevent the recurrence of ulcer is quite another matter." Temple compared the prophylactic use of a GI agent favorably to the short-term prophylactic use of cromolyn sodium as an OTC for specific events such as exercise-induced asthma or antigen-induced asthma. Temple indicated a generally favorable inclination toward a switch application for cromolyn sodium during comments at the May 9 meeting ("The Pink Sheet" May 15, p. 18). Marion, and its sucralfate OTC development partner Schering, have not disclosed the OTC formulation or claims structure for their planned switch for the product (circa 1991). However, Marion has discussed the switch project as a "transfer" of Carafate to OTC status, which appears to imply an attempt to move the product in its prescription dosage strength to the OTC market. The firm has noted that the indication will have to accommodate the ability of the patient to self-diagnose the condition being treated. That stricture would presumably rule out the current duodenal ulcer indication. Schering is responsible for taking the product through the FDA registration process. While at first glance sucralfate looks like an "ideal" candidate for OTC marketing, Garvey said he believes it may develop into a "tough switch." One of the "nettlesome" problems facing Marion and Schering in the OTC development of the problem, Garvey said, derives from urinary excretion evidence that the product leads to absorption of aluminum. "There is clearly absorption of aluminum when Carafate is administered in ulcer healing doses," Garvey contended. He noted that that absorption is not a problem in short-term dosing. Absorption is not mentioned in sucralfate's prescription labeling. With OTC use, Garvey said absorption will raise a number of issues for FDA in relation to use by patients with impaired renal function. The types of questions that FDA could be expected to raise, according to Garvey, include: "What happens to these [renal impaired] patients? We are really not so sure what happens with aluminum. What are toxic levels? How long does it take to cause damage? What is the damage? How is it manifest?" He characterized the problem as not "insurmountable" but "complicated." Sucralfate's ability to bring symptomatic relief may pose another hurdle for approval as an OTC. " For duodenal ulcer, and for several other indications," Garvey said, "the drug appears to provide very poor relief of putatively ulcer-related pain. So, it is not very good for symptoms as far as we can tell." Marion and Schering are approaching the OTC market through the professional community. The two companies are currently co-promoting the product to the medical community, paving the way for an "ethical" switch to OTC use. The current prescription indication is for short-term (up to eight weeks) treatment of duodenal ulcers. Marion has recently drawn a rebuke from FDA for promotions implying unapproved uses for Carafate. The company sent out "Dear Doctor" and "Dear Pharmacist" letters in early May acknowledging that Carafate has not been approved for prevention or treatment of gastric ulcers, gastritis, esophagitis, or stress ulcers ("The Pink Sheet" May 15, T&G-13). The combined attempt by Marion and Schering to build Carafate's name recognition and image in the medical community in anticipation of the eventual switch of the product could be significantly undercut by efforts to push the product beyond current labeling. For Marion, sucralfate is becoming an important core product for an expanding GI business. The company notes that monthly prescriptions in the three-month period ended March 31 exceeded 400,000. The product is expected to pass the $ 200 mil. sales mark in the fiscal year ending in June. Marion is also developing Pentasa, an ulcerative colitis product from the Danish firm Ferring. The company says that clinical results with Pentasa have been outstanding. The firm is reportedly looking at another anti-ulcer product as a development candidate.