Summary: Pharmexa today presented preclinical data from its RANKL AutoVac™
program against bone related disorders at the ASBMR conference
The ASBMR (American Society for Bone and Mineral Research) conference
“Targeting Bone Remodeling for the Treatment of Osteoporosis” is held December
6-7 in Washington DC.
The RANKL protein regulates osteoclast activity and bone resorption.
Neutralizing RANKL is effective at reducing bone destruction in models of
osteoporosis, rheumatoid arthritis and bone metastasis. Pharmexa is developing
a RANKL vaccine that bypasses immunological tolerance and induces antibodies
that effectively neutralize human RANKL. This is achieved using the AutoVac™
technology where the proprietary T-helper epitope PADRE® is inserted into a
recombinant RANKL protein which is then used for immunization.
At the ASBMR conference Pharmexa presented preclinical data which show that:
1) Pharmexa's PADRE®-RANKL AutoVac™ vaccine has a biological activity that is
about 30 times lower than native RANKL, which addresses theoretical safety
concerns associated to the RANKL molecule itself while maintaining appropriate
immunogenicity.
2) The PADRE®-RANKL AutoVac™ vaccine induces a dose-dependent antibody response
in rodents, with high antibody titres after four immunizations, as shown in the
figure below:
3) The PADRE®-RANKL AutoVac™ induces neutralizing antibodies which inhibit the
RANKL-induced osteoclastogenesis in vitro, as shown in the figure below:
4) The PADRE®-RANKL AutoVac™ vaccine generates an antibody response that
declined upon discontinuation of vaccination, but the antibody response could
be re-stimulated by a single vaccine boost, indicating induction of
immunological memory.
Dr. Achim Kaufhold, Executive Vice President, CMO and CSO summarizes: “The
results demonstrate that Pharmexa's proprietary vaccine candidate induced high
anti-RANKL antibody titres and that these antibodies decline over time, which
is a desirable feature of a vaccine for human use. The antibodies induced
neutralize native human RANKL in vitro. The results obtained in several rodent
animal models pave the way for further development of this novel
immunotherapeutic approach”.
Hørsholm, December 6, 2007
Jakob Schmidt
Chief Executive Officer
Additional information: Jakob Schmidt, Chief Executive Officer, telephone +45
4516 2525
Claude Mikkelsen, Vice President, Corporate Affairs and Communication,
telephone +45 4516 2525 or +45 4060 2558
Note to editors: Pharmexa A/S is a leading company in the field of active
immunotherapy and vaccines for the treatment of cancer, serious chronic and
infectious diseases. Pharmexa's proprietary technology platforms are broadly
applicable, allowing the company to address critical targets in cancer and
chronic diseases, as well as serious infectious diseases such as HIV,
influenza, hepatitis and malaria. Its leading programs are GV1001, a peptide
vaccine that has entered phase III trials in pancreatic cancer and phase II
trials in liver cancer, and HIV and hepatitis vaccines in phase I/II.
Collaborative agreements include H. Lundbeck, Innogenetics, IDM Pharma and
Bavarian Nordic. With operations in Denmark, Norway and USA, Pharmexa employs
approximately 105 people and is listed on the Copenhagen Stock Exchange under
the trading symbol PHARMX.
