Du Pont solidifies its leadin radiopharmaceutical market

CEO reports solid growth in cardiology segment

Du Pont Pharmaceutical of North Billerica, MA, is riding the waveof rising Cardiolite demand. All of the market-leading radiopharmaceuticalcompany's growth in 1995 stemmed from an expanding nuclear cardiologysegment, and nearly all of that was credited to Cardiolite, accordingto Kenneth Kasses, president.

In fact, the technetium-sestamibi-based myocardial perfusionagent accounted for 40% of nuclear medicine studies and salesof about $112 million last year, according to Las Vegas-basedconsultant Marvin Burns.

The number of myocardial studies performed with Cardiolitegrew about 10% last year, Kasses said. Thallium and, to a lesserextent, Du Pont's IV Persantine pharmacologic stressor, benefitedfrom nuclear cardiology's growth. The rest of the market was relativelyflat, he said.

Kasses credits increased clinical acceptance of myocardialperfusion as a diagnostic tool for evaluating cardiac patientswith fueling new demand. A Food and Drug Administration authorizationfor Du Pont to market Cardiolite for cardiac risk stratificationand studies accompanying pharmacologic stress has contributedto its growth, he said.

Du Pont officials are optimistic about Cardiolite's potentialas a cancer-detecting agent as well. In 1995, Du Pont filed asupplemental new drug application with the FDA, requesting approvalto market Cardiolite for use in breast cancer diagnosis, accordingto Robert Williams, director of market development.

Papers presented at the Society of Nuclear Medicine meetingadded to preliminary evidence favoring the use of technetium-99m-sestamibifor breast cancer detection. A blinded multicenter study conductedby Dr. Iraj Khalkhali, chief of breast imaging at Harbor-UCLAMedical Center in Torrance, CA, examined the diagnostic accuracyof Tc-99m-sestamibi scans performed on 673 patients previouslydiagnosed with palpable or nonpalpable abnormalities on mammography.

The clinical trial determined that the nuclear medicine procedurewas as sensitive to palpable and nonpalpable disease as mammography,and scored significantly higher in terms of positive predictivevalue.

A paper presented by Dr. Ramon Taillefer of Hôtel-Dieuin Montreal determined that the scintigraphic test using sestamibiis diagnostically valuable in detecting axillary lymph node involvementin breast cancer. Results from a separate study of 190 patientsscanned by Taillefer confirmed the high specificity and sensitivityof Tc-99m-sestamibi in detecting breast cancer.

In combination, these preliminary studies suggest that scintimammographymay be an appropriate adjunct to x-ray mammography in the diagnosticexamination of equivocal cases before excisional biopsy, Williamssaid.

"We see our technique possibly fitting as an additionaltool to find out who really has cancer," he said.

Quadramet (samarium-153-EDTMP) is a second area of clinicalinterest for Du Pont, according to Williams. Du Pont has contractedwith the product's developer, Cytogen, for manufacturing and NorthAmerican marketing rights for the agent. After gaining FDA clearance,Quadramet will give Du Pont its first shot at nuclear medicine'sburgeoning therapeutic segment. The new drug application, submittedin the second quarter of 1995, requests approval for labelingthat refers to relief of pain due to osteoblastic metastases foundmainly in prostate and breast cancer patients.

Du Pont also holds the rights for future marketing and distributionof Verluma, the brand name for a monoclonal antibody fragmentlabeled with technetium. Clinical work relating to the agent,designed for small-cell lung cancer staging, was completed byNeoRx of Seattle. An FDA oncology drug advisory committee recommendedapproval in December 1995; final regulatory action is pending.