Munich, Germany, 02 May, 2011. WILEX AG (ISIN DE0006614720, Frankfurt Stock Exchange) announced the granting of US commercialisation rights for RENCAREX® (Girentuximab) to Prometheus Laboratories Inc. (Prometheus), San Diego, CA, USA. Prometheus is an established specialty pharmaceutical and diagnostics company with a proven track record in gastroenterology and oncology.

In return, WILEX will receive $39 million, $19 million upon signing and either $20 million after twelve months or alternatively the European commercial rights for an undisclosed product from Prometheus. In addition WILEX will receive milestone payments and royalties on US net sales of RENCAREX®. Furthermore Prometheus will co-fund a portion of the ongoing development of RENCAREX®. This potentially values the deal at over $145 million plus royalties on net sales in the United States.

RENCAREX® is a Phase III product candidate for adjuvant use in non-metastatic clear cell Renal Cell Cancer (ccRCC). The deal includes the potential development in further indications. Prometheus markets Proleukin®, an oncology product indicated for metastatic renal cell carcinoma and metastatic melanoma, in the US. If RENCAREX® receives approval in the USA Prometheus would be able to offer a treatment for both adjuvant and metastatic kidney cancer.

Professor Olaf G. Wilhelm, CEO of WILEX AG, commented: “This is the deal we have been looking for, not only in financial, but also in commercial and strategic terms. We are very excited about WILEX’s new partnership with Prometheus since Prometheus has a proven track record in commercialising pharmaceutical and diagnostic products.”

“We are very pleased to enter into this partnership with WILEX as we continue to build our oncology franchise,” said Joseph M. Limber, President and Chief Executive Officer of Prometheus. “RENCAREX® is a great strategic fit with our current oncology portfolio in renal cell carcinoma. There is no product currently approved in the United States for patients who could have recurrence of ccRCC after a kidney resection. We look forward to working with WILEX to complete the development process and commercialise RENCAREX® in the United States.”