Aeras and Crucell Announce TB Vaccine Clinical Trial in Kenya; Promising Vaccine Candidate Advances to Phase II Safety Study in South Africa

Leiden, The Netherlands/Paris, France - Dutch biopharma company Crucell N.V. (Euronext, Nasdaq: CRXL; Swiss Exchange: CRX) and the Aeras Global TB Vaccine Foundation today announce the start of a Phase I clinical trial in Kenya of the jointly developed tuberculosis (TB) vaccine candidate, AERAS-402/Crucell Ad35. The announcement is made in the lead up to the 39th Union World Conference on Tuberculosis and Lung Disease in Paris, France (16-20 October, 2008).

This first-ever study of the new TB vaccine candidate in Kenya will be conducted by the Walter Reed Project-Kenya (WRP) at Kombewa, near Kisumu, Western Kenya. The main parameters of the study will be to test the safety of the candidate in healthy adults, all of whom have been previously vaccinated with the Bacille Calmette-Guérin (BCG) vaccine and a subset of whom have evidence of having been exposed to TB.

“I am glad that a high burden country like Kenya has been selected in these broader comprehensive efforts in advancing new tools that are urgently required in global TB control efforts, more so in an era where TB-HIV co-infection is a great challenge.” said Lucy Chesire, a Kenyan TB Advocate.

Crucell and Aeras also announce the start of the first Phase II study of AERAS-402/Crucell Ad35. The study is being conducted in Cape Town, South Africa by the University of Cape Town Lung Institute in conjunction with the South African Tuberculosis Vaccine Institute. Screening of volunteers has begun and immunization is scheduled to start in the next couple of weeks. The candidate will be tested in 82 adults who have had active TB.

“There are many potential uses of a new TB vaccine. Therefore, it is important to determine a candidate’s safety and immune responses in those who have already been exposed or have had active TB disease,” said Jerald C. Sadoff, MD, President and CEO of Aeras. “We are pleased to be working with two outstanding organizations in Kenya and South Africa - the Walter Reed Project-Kenya and the University of Cape Town - to move this promising candidate forward in development.”

“We are very pleased with our continued progress with this next generation TB vaccine,” said Dr. Jaap Goudsmit, Crucell’s Chief Scientific Officer. “The initiation of these two new studies through our fruitful collaboration with Aeras puts us another step closer to our ambition of reducing the global burden of this fatal disease.”

Aeras and Crucell began jointly developing this vaccine candidate in 2004 using Crucell’s AdVac® vaccine technology and PER.C6® manufacturing technology. A first Phase I clinical trial launched in October 2006 in Kansas, USA indicated that the vaccine candidate is safe in healthy adults in the US. The preliminary results of a second study, launched in May 2007, were presented at the ’TB Vaccines for
the World’ conference in April 2008. Preliminary data showed both critical arms of the cellular immune system, CD4 and CD8 immune T-cells, were induced and that in those participants who responded, CD8 immune responses were considerably higher than had ever previously been seen in a TB vaccine study.

A third phase I study in healthy adults in St. Louis, Missouri, USA was launched in December 2007 and focuses on the immunogenicity and safety of two AERAS-402/Crucell Ad35 boost doses administered at three to six month intervals after BCG priming in healthy adults.

About Tuberculosis
Tuberculosis is the world’s second deadliest infectious disease, with over 9 million new cases diagnosed in 2006. According to the World Health Organization (WHO), an estimated 1.7 million people died from TB in 2006. One third of the world’s population has been infected with the TB bacillus and current treatment takes 6-9 months. The current TB vaccine Bacille Calmette-Guérin (BCG), developed over 85 years ago, reduces the risk of severe forms of TB in early childhood but is not very effective in preventing pulmonary TB in adolescents and adults - the populations with the highest rates of TB disease. TB is changing and evolving, making new vaccines more crucial to controlling the pandemic. Tuberculosis is now the leading cause of death for people living with HIV/AIDS, particularly in Africa. Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) are hampering treatment and control efforts.

About AdVac® technology and Ad35
AdVac® technology is a vaccine technology developed by Crucell and is considered to play an important role in the fight against emerging and re-emerging infectious diseases, and in biodefense. The technology supports the practice of inserting genetic material from the disease-causing virus or parasite into a ’vehicle’ called a vector, which then delivers the immunogenic material directly to the immune system. Most vectors are based on an adenovirus, such as the virus that causes the common cold. The AdVac® technology is specifically designed to manage the problem of pre-existing immunity in humans against the most commonly used recombinant vaccine vector, adenovirus serotype 5 (Ad5), without compromising large-scale production capabilities or the immunogenic properties of Ad5. AdVac® technology is based on adenoviruses that do not regularly occur in the human population, such as Ad35. In contrast to for instance Ad35 antibodies, antibodies to Ad5 are widespread among people of all ages and are known to lower the immune response to Ad5-based vaccines, thereby impairing the efficacy of these vaccines. All vaccine candidates based on AdVac® are produced using Crucell’s PER.C6® production technology.

About PER.C6® technology
Crucell’s PER.C6® technology is a cell line developed for the large-scale manufacture of biopharmaceutical products including vaccines. The production scale potential of the PER.C6® cell line has been demonstrated in an unprecedented successful bioreactor run of 20,000 liters. 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 Aeras
The Aeras Global TB Vaccine Foundation is a non-profit organization working as a Product Development Partnership to develop new tuberculosis vaccines and ensure that they are distributed to all who need them around the world. Aeras is funded by the Bill & Melinda Gates Foundation, the Netherlands Ministry of Foreign Affairs, the Danish International Development Agency, the Research Council of Norway and the U.S. Centers for Disease Control and Prevention. Aeras, with over 130 employees, is based in Rockville, Maryland, where it operates a state-of-the-art manufacturing and laboratory facility. In 2008, the Aeras Africa Office was opened in Cape Town, South Africa. For more information, please visit www.aeras.org.

About SATVI
The South African Tuberculosis Vaccine Initiative is located in the Institute of Infectious Disease and Molecular Medicine at the University of Cape Town (UCT). Since 1999, with funding largely from the Aeras Global TB Vaccine Foundation, SATVI has developed the capacity to conduct registration standard vaccine trials at a site in Worcester, some 110km outside of Cape Town, where rates of tuberculosis are among the highest in the world. SATVI has a state of the art immunology laboratory located at UCT, where the complex assays needed for TB vaccine studies can be performed. In the last six years, SATVI has conducted a number of very large field trials and epidemiological cohort studies of the type that will be necessary to test the efficacy of new tuberculosis vaccines, involving thousands or tens of thousands of participants, as well as a number of smaller Phase I and II trials of new TB vaccines. In addition, SATVI conducts cutting edge basic science research aimed at better understanding the human immune response to tuberculosis and to tuberculosis vaccines. For more information, please visit www.satvi.uct.za.

About University of Cape Town Lung Institute
The University of Cape Town Lung Institute is located on the campus of the Faculty of Health Sciences. It provides clinical services and conducts research in the fields of respiratory medicine, allergies, occupational medicine and dermatology. Special emphases in research are epidemiology, allergy diagnostics, lung physiology, clinical pharmacology and community-based interventions for improving disease management and improving health. In association with various departments of the University, the Lung Institute provides training for students in the health professions and collaborates broadly with training and research institutions elsewhere in South Africa and abroad. The public is served by educational and health promotional activities and by several unique clinical and community services. For more information, please visit www.lunginstitute.co.za.

About Walter Reed Project-Kenya
The Walter Reed Project-Kenya (WRP) is the U.S. Department of Defense’s HIV program in Kenya. Activities in Kenya are centered at the U.S. Army Medical Research Unit-Kenya (USAMRU-K) on the campus of the Kenyan Medical Research Institute (KEMRI) in Nairobi. The U.S. military has maintained a substantial program for infectious disease research in Kenya for nearly 40 years. For more information, please visit www.hivresearch.org/global-efforts/kenya.html.

About Crucell
Crucell N.V. (Euronext, NASDAQ: CRXL; Swiss Exchange: CRX) is a global biopharma company focused on research, development, production and marketing of vaccines, proteins and antibodies that prevent and treat primarily infectious diseases. 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 aluminum-free hepatitis A vaccine on the market. The Company has a broad development pipeline, with several product candidates based on its unique PER.C6® production technology. The Company licenses its PER.C6® technology and other technologies to the biopharmaceutical industry. Important partners and licensees include DSM Biologics, sanofi-aventis, Novartis, Wyeth 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 thousand people. For more information, please visit www.crucell.com.

Forward-looking statements
This press release contains forward-looking statements that involve inherent risks and uncertainties. We have identified certain important factors that may cause actual results to differ materially from those contained in such forward-looking statements. For information relating to these factors please refer to our Form 20-F, as filed with the U.S. Securities and Exchange Commission on May 7, 2008, and the section entitled “Risk Factors”. The Company prepares its financial statements under International Financial Reporting Standards (IFRS).