WASHINGTON _ The FDA's Center for Devices and RadiologicalHealth (CDRH) _ which regulates in vitro diagnostic (IVD)products, including those with a biologics feature _ is giving seriousconsideration to a petition from Centocor Inc. to reclassify the way itregulates IVDs.

Centocor, based in Malvern, Pa., petitioned CDRH in mid-Aprilseeking reclassification of its serum tumor tests used for patientmonitoring purposes from the current class III premarket approvalcategory into class II called special controls. Class III is generallyused by the FDA to regulate new tests and medical devices which theagency believes raise concerns about safety and effectiveness.

Class III is inappropriate because "serum tumor markers have beenavailable for 10 to 20 years and have accumulated a good record ofsafe and effective use," according to the petition.

Centocor's assistant director of regulatory affairs, Chris Zalesky, toldBioWorld Today that "CDRH accepted our petition and told us theyare delighted with its content." A CDRH advisory committee will acton the petition in mid-September.

"CDRH told us they welcome the petition because it helps themsatisfy their statutory obligation to reclassify IVDs by the end of1993 into Class I or Class II or explain the reasons why," Zaleskysaid. "Congress imposed the requirement on FDA in 1990 butstaffing limitations have prevented the agency from meeting theCongressional mandate," Zalesky said.

Of the 35 IVDs on the worldwide market, six are manufactured byCentocor. Only five of the 35 are approved for marketing in the U.S.Zalesky said so few manufacturers have applied to FDA for Class IIIapproval because of the expensive studies that are required todocument clinical utility. "Those studies cost up to $6 million, coststhat in some cases exceed the annual revenues from the product," hesaid.

Centocor's petition has political resonance as Congress considersFDA reform legislation. "Centocor's petition fits nicely with thecurrent sentiments about FDA reform," said Bruce Carroll,Centocor's director of government affairs. "Right now, the way FDAis regulating tumor markers is comparable to pounding a square peginto a round hole.

"By reclassifying them, FDA will be able to focus its resources onhigh risk devices and speed approval of others," Carroll said.

Reclassification Of Reagents Also Sought

Centocor also is pushing the FDA to reclassify special purposereagents into a "more appropriate regulatory box," said Zalesky.

"FDA is concerned about the potentially huge market that could becreated from monoclonal and polyclonal antibodies, antigens, geneticprobes and other special purpose reagents," Zalesky said. "Given thehuge number of genetic probes that could be crafted, the potentialmarket appears limitless."

Special purpose reagents can't be used on their own and mustundergo further manufacturing steps and extensive qualification andvalidation using patient specimens. Most often they are used in thedevelopment and manufacture of IVD systems or assays by IVDmanufacturers _ such as Centocor _ or by clinical laboratories.

The FDA suspects that many special purpose reagents not labeled forresearch or investigational use are also being used for manufacturingpurposes in the production of IVD test systems.

Centocor isn't jumping into that market until the FDA makes up itsmind about how to reclassify these products. Centocor literally hasthese solutions in a freezer awaiting FDA action. "We are reluctant toget into the business without making sure that the rules are clear,"Zalesky said.

Centocor representatives met with FDA officials in late April andreceived assurances from CDRH staffers that the agency is receptiveto industry proposals for regulatory improvements.

Centocor responded with a proposal seeking reclassification ofgeneral purpose reagents as Class I devices subject only to goodmanufacturing practices (GMP) and no premarket notification.General purpose reagents were first classified into Class III in 1976by default because no similar product existed to which they could becompared.

Specifically, the FDA is considering making special purpose reagentssubject to registration, listing and labeling restrictions in addition toGMPs. Sale of these reagents would be limited to laboratoriescurrently licensed by the federal government to perform highcomplexity testing as defined by the Clinical LaboratoryImprovements Amendments of 1988.

The FDA is concerned that current premarket approval requirementson manufacturers of special purpose reagents may not be strictlynecessary or practical, said Zalesky. Neither FDA nor themanufacturers play a central role in how these reagents are used, howthe assay is validated or claims that may be made about its use orperformance, he said.

Zalesky also contends that the FDA does not have the staff resourcesto handle the flood of premarket approval applications that wouldpour into the agency if they were made subject to this level of review.n

-- Michele L. Robinson Washington Editor

(c) 1997 American Health Consultants. All rights reserved.