May 18, 2006
Terumo develops liposome for anticancer drug
jointly with Yakult Honsha Co. Ltd.
Terumo Corporation (Head office: Shibuya-ku, Tokyo; President: Akira Takahashi)
is set to launch a joint development with Yakult Honsha Co. Ltd.(Head office:
Minato-ku, Tokyo; President: Sumiya Hori) for a liposomal formulation encapsulating
an anticancer drug. A phase I clinical study will be started in May 2006
in the United States.
This formulation encapsulates irinotecan, an effective Campto injection
component (generic name: irinotecan HCl). Irinotecan was developed by Yakult
and is broadly used as a drug for colon cancer. The liposome encapsulating
irinotecan was developed by Terumo. As a result of the encapsulation of
irinotecan in the liposome, the formulation is expected to improve the sustainability
of drug efficacy and target cancer tissues with reduced adverse effects.
In the phase I clinical study to be conducted in the United States, Terumo
will supply the liposome preparation, while Yakult will conduct the clinical
study.
<<Outline of liposome preparation>>
Development code: IHL-305
Content of preparation:
Polyethylene glycol-modified liposome-encapsulated
preparation
A 10 ml vial contains 50 mg of encapsulated irinotecan.
Target cancer: solid cancer
Reference information: What is a liposome?
An anticancer drug, when administered, circulates throughout the whole body
and may cause unexpected effects not only on diseased but also on healthy
sites. In other words, the drug does not always act on the cancer tissues,
so that it may cause various adverse effects. A method for efficiently concentrating
drug at cancer tissues is considered to enhance local drug effect and reduce
systemic adverse effect. It is DDS (Drug Delivery System) technology.
The liposome is one of DDS technology and is a microscopic lipid particle
produced when lipids are dispersed in a water phase. ("Lipo-" and "-some"
mean lipid and pouch, respectively). By encapsulating a drug within the
membrane of or inside this lipid-made microscopic particle, the drug can
be delivered to target sites with reduced systemic exposure.
<<Features of Terumo's liposome>>
The liposome developed by Terumo with its proprietary technology is controlled
by specific particle size. The liposome can target at cancer tissue and
continue the effect for long periods of time by the modification of the
liposome with polyethylene glycol.
A cancer tissue that exhibits quicker cell proliferation than normal cells
is accompanied by constant vascularization. It is known that the resulting
vessel wall tissue, therefore, has many gaps of several hundred nm in size.
The liposome preparation does not penetrate normal vessel walls. However,
it may penetrate the coarse vessel walls peculiar to cancer tissue and easily
reach diseased sites. Moreover, as lymph ducts with excretion functions
are underdeveloped in cancer tissues, a liposome preparation delivered into
cancer tissue is hardly excreted, so that the effect of a drug can be sustained
for a longer time in cancer tissue.
(Note) Forward-looking statements included in this release were determined by Terumo based on the best information available at the time of writing and are subject to potential risks and uncertainties. Therefore, please note that, due to various factors, the actual implementation may differ from what is described here.
