Crucell Announces Start of Rabies Phase I Antibody Cocktail Clinical Study in India four months after launching initial US Trial

Leiden, The Netherlands, April 4, 2007 - Dutch biotechnology company Crucell N.V. (Euronext, NASDAQ: CRXL; Swiss Exchange: CRX) today announced that the Rabies monoclonal antibody product it is developing has entered a Phase I clinical study in India, four months after launching a similar study in the US. Crucell has developed a human monoclonal antibody product for the post-exposure prophylaxis of rabies, using Crucell's MAbstract® and Crucell's PER.C6® technologies. This second Phase I study is closely linked to the initial Phase I study that is currently being performed in the US. Both studies are conducted under FDA authority, the Indian Phase I study gained approval upon review by the Drug Controller-General of India (DCGI).

Related Results

The clinical trial will be a randomized, double-blind, placebo controlled study in 44 healthy volunteers that will test the antibody product alone in a dose escalation as well as in combination with rabies vaccine. The study, funded by Crucell, will be conducted through a clinical research organization in Mumbai, India. The main parameters under investigation will be safety, tolerability and (rabies virus) neutralizing activity.

"We are very pleased that would could initiate this second Phase I trial, as it follows favorable interim safety and tolerability data from the initial US study," said Jaap Goudsmit, Chief Scientific Officer at Crucell. "The clinical testing of the Rabies antibody cocktail in Asia is the next important step for the program, as the global burden of Rabies is mostly affecting this continent. In addition to clinical evaluation of the rabies mAb cocktail in India, we are currently exploring the conduct of clinical trials in other Asian countries, including China."

Dr. Deborah Briggs, Director of the Alliance for Rabies Control added: "There is a tremendous need for additional sources of rabies immune globulins (RIG) throughout the world, especially in Asia where less than 3 % of patients undergoing post-exposure prophylaxis actually receive passive immune products. Hopefully, new Mab products like this one will soon be available to help to solve the shortage problem and save human lives."

About Rabies

Rabies is a viral disease of mammals most often transmitted through the bite of a rabid animal. The virus infects the central nervous system, causing encephalitis (inflammation of the brain) and ultimately death if medical intervention is not sought promptly after exposure.

There is no proven treatment for rabies once symptoms of the disease have appeared. Lethal rabies is prevented by post-exposure prophylaxis (PEP) via the combined administration of a rabies vaccine and RIG following the bite of a rabid animal. Neither vaccine nor RIG are effective independently of one another. Current supply and quality of rabies vaccine is sufficient, but RIG is in short supply and carries certain safety risks.

Crucell has conceived an antibody product that is produced using its PER.C6® technology, which offers large-scale manufacturing capabilities and production under serum-free culture conditions. Crucell's rabies monoclonal antibody cocktail offers the potential for replacing the traditional serum-derived products that are currently still in use for the treatment of rabies.

Rabies is prevalent in all the continental regions of Europe, Asia, America and Africa. Globally, approximately 10 million people a year are vaccinated after exposure to rabies. Some 40,000 to 70,000 people are thought to die of the disease each year, mainly in Asia and Africa.

About MAbstract® technology

Crucell's proprietary MAbstract® technology can be used to discover drug targets, such as cancer markers or proteins from infectious agents including bacteria and viruses, and identify human antibodies against those drug targets.

About PER.C6® technology

Crucell's PER.C6® technology is a cell line developed for the large-scale manufacture of biopharmaceutical products including vaccines. Compared to conventional production technologies, the strengths of the PER.C6® technology lie in its excellent safety profile, scalability and productivity under serum-free culture conditions. These characteristics, combined with its ability to support the growth of both human and animal viruses, make PER.C6® technology the biopharmaceutical production technology of choice for Crucell's current and potential pharmaceutical and biotechnology partners.

About Crucell

Crucell N.V. (Euronext, NASDAQ: CRXL; Swiss Exchange: CRX) is a biotechnology company focused on research, development and worldwide marketing of vaccines and antibodies that prevent and treat infectious diseases as well as therapeutic proteins for various indications. Its vaccines are sold in public and private markets worldwide. Crucell's core portfolio includes a vaccine against hepatitis B, a fully-liquid vaccine against five important childhood diseases, and a virosome-adjuvanted vaccine against influenza. Crucell also markets travel vaccines, such as the only oral anti-typhoid vaccine, an oral cholera vaccine and the only aluminium-free hepatitis A vaccine on the market. The Company has a broad development pipeline, with several Crucell products based on its unique PER.C6® production technology. The Company licenses this and other technologies to the biopharmaceutical industry. Important partners and licensees include DSM Biologics, sanofi aventis, GSK and Merck & Co. Crucell is headquartered in Leiden (the Netherlands), with subsidiaries in Switzerland, Spain, Italy, Sweden, Korea and the US. The Company employs over a 1000 people. For more information, please visit www.crucell.com .