166Ho-microspheres is a product developed at the University Medical Center of Utrecht (The Netherlands) on the basis of microparticles loaded with 166Ho and sold under the name 166Ho-QuiremSpheres®. These particles are obtained by direct activation of 165Ho pre-loaded poly-L-lactic acid (PLLA) particles using a direct, high-Neutron flux from a reactor.

This product was filed as a Brachytherapy drug and as such still to be considered as a medical device. QuiremSpheres® received CE mark in April 2015.

166Ho-microspheres are analogues of 90Y-microspheres and intended for implantation into hepatic tumors by delivery via the hepatic artery to be used in patients with unresectable liver tumors.

Target/Mechanism: Brachytherapy

Carrier/Ligand: n/a

Radiation Type: beta electrons (β)