Diagnostic Products Corporation Acquires Nonexclusive Rights to a Key Cardiac Marker, NT-proBNP, from Roche Diagnostics—Agreement widens access to unique marker for heart failure and allows for better/earlier/improved therapy.

LOS ANGELES February 11, 2004—Roche Diagnostics and Diagnostic Products Corporation (NYSE:DP) announced today that Diagnostic Products Corporation (DPC) has been granted a nonexclusive license under patent rights of Roche Diagnostics relating to the development, manufacture and marketing of immunoassays that detect a key marker of congestive heart failure (CHF), NT-proBNP (N-terminal prohormone brain natriuretic peptide).

"We feel that NT-proBNP is a unique diagnostic and management tool, and licensing it broadly will help us to maximize the benefit of this product to the patients, the medical community and our shareholders. Diagnostic Products Corporation is an important partner because of its strong position in the heterogeneous immunoassay market" said Heino von Prondzynski, Head of Roche Diagnostics and a member of Roche's Corporate Executive Committee.

"We are pleased to be able to move forward with development of an NT-proBNP assay-a high priority for DPC in 2004" said Ira Ziering, Vice President, Business and Legal, Diagnostic Products Corporation. "This assay will be an important addition to DPC's cardiac menu because it is not only a diagnostic marker of congestive heart failure but also a prognostic marker for this condition and for acute coronary syndromes."

B-type natriuretic peptide (BNP) is secreted by the left ventricle when the heart is unable to pump blood efficiently. BNP dilates blood vessels and promotes sodium and water loss, reducing fluid load on the heart and improving cardiac performance. Synthetic BNP, marketed as Natrecor^® (nesiritide), is a treatment for heart failure. Thus, measuring BNP does not necessarily allow the physician to differentiate between elevated BNP levels due to drug treatment and elevated BNP due to ventricular dysfunction.

By contrast, NT-proBNP, which is released when BNP is cleaved from its precursor, proBNP, has no interference with such a treatment. Elevated plasma NT-proBNP indicates the presence of heart failure and provides information about its severity: the higher the blood level of NT-proBNP, the more serious the condition. NT-proBNP levels have been demonstrated to be a diagnostic aid in ruling out left ventricular dysfunction, allowing physicians to differentiate between heart failure and lung disorders with similar symptoms. The test is further indicated for the risk stratification of patients with acute coronary syndrome and congestive heart failure.

According to the American Heart Association, 4.8 million Americans are afflicted with CHF, with 550,000 cases diagnosed each year. There are a number of causes of the disease: the most important are coronary artery disease, high blood pressure, diabetes, inflammation and intoxications. Significantly, heart failure is the leading cause of Medicare hospitalization in the US, accounting for 18 billion dollars per year in direct costs.

Prevalence of heart failure is expected to continue to rise, due to the aging population and increase in acute coronary syndrome survival. Heart failure is often difficult to diagnose, since its symptoms are nonspecific and are sometimes confused with those of other conditions such as chronic obstructive pulmonary disease. Echocardiography, the currently used standard for diagnosis of left ventricular dysfunction, is expensive and not always easily accessible.

About Diagnostic Products Corporation
Founded in 1971, Diagnostic Products Corporation (DPC) is the global leader dedicated exclusively to immunodiagnostic testing. The Company's product menu includes over 400 tests to measure microorganisms, hormones, drugs and other medically important substances present at infinitesimal concentrations in body fluids and tissues. DPC also designs and manufactures automated laboratory instrumentation which provides fast, accurate results while reducing labor and reagent costs. DPC sells its products to hospitals, clinics and laboratories domestically and in over 100 countries. Additional Company information can be found on the Company's website at www.dpcweb.com.

About Roche and the Roche Diagnostics Division
Headquartered in Basel, Switzerland, Roche is one of the world's leading innovation-driven healthcare groups. Its core businesses are pharmaceuticals and diagnostics. Roche is number one in the global diagnostics market, the leading supplier of pharmaceuticals for cancer and a leader in virology and transplantation. As a supplier of products and services for the prevention, diagnosis and treatment of disease, the Group contributes on a broad range of fronts to improving people's health and quality of life. Roche employs roughly 65,000 people in 150 countries. The Group has alliances and research and development agreements with numerous partners, including majority ownership interests in Genentech and Chugai. Roche's Diagnostics Division, the world leader in in-vitro diagnostics with a uniquely broad product portfolio, supplies a wide array of innovative testing products and services to researchers, physicians, patients, hospitals and laboratories worldwide. For further information, please visit our websites www.roche.com and www.roche-diagnostics.com.