Promising Results of Novel Combination Vaccine
LEIDEN, Netherlands, January 5, 2012 /PRNewswire/ –
Preclinical Study Provides Strong Rationale for HIV Vaccine Clinical Trials
Results from a recent study present new insights into the immune responses underlying
protection against HIV infection and provide a path forward for HIV vaccine development.
Published in this week’s online version of the journal Nature, the study shows that novel
vaccine combinations can provide partial protection against infection by Simian
Immunodeficiency Virus (SIV), a virus similar to HIV, in rhesus monkeys. In addition, the
study showed in the animals that became infected, the optimal vaccine combinations also
substantially reduced the amount of virus in the blood. The study was a collaboration
between Crucell Holland B.V., the Beth Israel Deaconess Medical Center and Ragon Institute
of MGH, MIT and Harvard, and the U.S. Military HIV Research Program at the Walter Reed
Army Institute of Research.
Preclinical studies of HIV-1 vaccine candidates have typically shown post-infection
virologic control, but protection against becoming infected has previously only been
reported using less rigorous viral challenges. This proof-of-concept study, which tested
MVA, Ad26, and Ad35 vector-based vaccines, is the first to show partial vaccine protection
in the stringent animal model involving heterologous, neutralization-resistant SIVmac251
viral challenges in rhesus monkeys. The new Ad26/MVA and Ad35/Ad26 vector-based vaccine
regimens resulted in more than 80% reduction in the per-exposure probability of
acquisition of infection against repetitive challenges of SIV.
“This study allowed us to evaluate the protective efficacy of several prime-boost
vaccine combinations, and these data will help guide the advancement of the most promising
candidates into clinical trials,” said Jaap Goudsmit, M.D., Ph.D., Chief Scientific
Officer, Crucell Holland B.V.
Further analysis also provided insights into the immune responses that may correlate
with protection, called “immune correlates.” The results show that antibodies to Env (the
envelope protein that makes up the outer coat of the virus) correlated with preventing
infection, whereas both T cell and antibody responses correlated with control of
post-infection viral replication. These distinct correlates likely reflect fundamentally
different mechanisms needed to block establishment of infection compared with controlling
viral replication after infection. Goudsmit also noted that “we have clearly shown that
including Env in the vaccine is beneficial.”
These new preclinical findings provide support for advancing the Ad26/MVA prime-boost
vaccine candidate into clinical development.
The research was supported by the National Institute of Allergy and Infectious
Diseases (NIAID); the Ragon Institute of MGH, MIT, and Harvard; and MHRP.
Crucell Holland B.V. is one of the Janssen Pharmaceutical Companies of Johnson &
This press release contains “forward-looking statements” as defined in the Private
Securities Litigation Reform Act of 1995. The reader is cautioned not to rely on these
forward-looking statements. These statements are based on current expectations of future
events. If underlying assumptions prove inaccurate or unknown risks or uncertainties
materialize, actual results could vary materially from the expectations and projections of
Crucell Holland B.V. and/or Johnson & Johnson. Risks and uncertainties include, but are
not limited to, general industry conditions and competition; economic factors, such as
interest rate and currency exchange rate fluctuations; technological advances and patents
attained by competitors; challenges inherent in new product development, including
obtaining regulatory approvals; domestic and foreign health care reforms and governmental
laws and regulations; trends toward health care cost containment; and increased scrutiny
of the healthcare industry by government agencies. A further list and description of these
risks, uncertainties and other factors can be found in Exhibit 99 of Johnson & Johnson’s
Annual Report on Form 10-K for the fiscal year ended January 2, 2011. Copies of this Form
10-K, as well as subsequent filings, are available online at http://www.sec.gov,
http://www.jnj.com or on request from Johnson & Johnson. Neither Crucell Holland B.V.
nor Johnson & Johnson undertake to update any forward-looking statements as a result of
new information or future events or developments.)
SOURCE Crucell N.V