Aprogenex amends agreement with Dianon Systems.

HOUSTON--(BUSINESS WIRE)--Nov. 28, 1994--Aprogenex Inc. (ASE:APG) Monday announced that it has amended the terms of its limited U.S. license agreement with Dianon Systems Inc.

The amended terms of the license change the pricing terms for future sales to Dianon and change the term of the license agreement. Although no assurances can be made at this point, sales to Dianon are expected to commence in 1995, according to Joel Bresser, Ph.D., president and chief executive officer of Aprogenex.

``We are pleased to have revised the terms of the contract with Dianon,'' Bresser said. ``Dianon is committed to providing innovative laboratory tests to a focused group of medical specialists. This agreement provides an excellent route for Aprogenex to introduce our GenSite assay in the U.S. and educate physicians on its benefits.''

In June 1993, Aprogenex executed a license that provided for the limited use of its prenatal genetic test, the GenSite assay, by Dianon. Dianon is expected to use the test to conduct clinical investigations under its own protocols. The license limits use of the product to testing in Dianon's laboratories in the United States.

The company will separately seek Food and Drug Administration approval of this test, and the license converts to a nonexclusive arrangement after such approval. The amended contract increases the price Dianon will pay for the product both before and after FDA approval. As previously disclosed, the terms of the contract had been under renegotiation for several months.

The GenSite assay is being developed as a rapid, cost-effective method for screening pregnancies for early detection of genetic abnormalities. Performed using a maternal blood sample, the assay avoids the risks associated with amniocentesis and chorionic villus sampling.

In October of this year, Aprogenex signed an exclusive agreement with Cellmark Diagnostics, a business unit of Zeneca Group (NYSE:ZEN), for the distribution of the GenSite prenatal genetic testing assay in Europe. Aprogenex currently estimates that the GenSite assay will be launched in Europe during the first half of 1995. However, the timing of the launch and other matters are subject to numerous contingencies.

Dianon Systems, with headquarters in Stratford, Conn., is a leading provider of specialized clinical and anatomic pathology services and integrated information products. Specializing in cancer and genetic testing, the company markets its services to oncologists, urologists and gynecologists throughout the United States and selected markets in Europe and Japan.

Aprogenex develops and intends to manufacture and market DNA probe-based diagnostic test systems based on its proprietary RIGHTechnology, which is broadly applicable to extensive markets in genetics, oncology, virology and microbiology.

The company is in the clinical-trial process with its GenSite maternal blood prenatal genetic testing assay and in preclinical development with its PapPlus HPV diagnostic assay and two HIV diagnostic and staging tests, the Virafy and ViraFlow assays.

CONTACT: Aprogenex Inc., Houston

              J. Donald Payne, 713/748-5114
                   or
              Keatinge/Seaton Communications
              Richard Keatinge, 619/625-2100
                   or
              Lippert/Heilshorn & Associates
              Michele Fasano, 212/838-3777