Prof. Kamal Mustafa, University of Bergen; Prof. Anna Finne Wistrand, KTH ROYAL INSTITUTE OF TECHNOLOGY
A number of patients suffering from difficult to heal non-union fractures of long bones (e.g. tibia, femur) or segmental bone defects (loss of large fragments of long bones due to disease or injury), are not responding to conventional treatment. Current treatments include autograft (own bone), allograft (donor bone), synthetic bone substitutes, stem cells and recombinant human bone morphogenetic protein 2. They provide suboptimal effects or sometimes no improvement in a number of patients. These methods also have their downsides, such as limited amount of material and post operational complications in the case of autografts and allografts. Often combination of methods is used to increase the odds of successful treatment. There is therefore a need for novel options, which are as efficacious as autograft, but with less burden on the patient. Fracture healing requires mechanical stability as well as a viable biologic microenvironment, so treatments should be osteoinductive, osteoconductive, osteogenic and angiogenic, as well as providing mechanical support. The proposed technology has those properties.
The core of the technology is the scaffold backbone made of biodegradable 3D-printed polycaprolactone (PCL) mimicking long bone structure. The scaffold consists of external layer of compact bone-like structure and inner cavity forming a channel for blood vessels. The cavity is of triangular shape providing proper mechanical strength to the structure. Empty spaces between the external layer and the channel, corresponding to sponge bone, are filled with fibrous materials or hydrogels providing environment for stem cells and forming blood vessels. Structural design and materials making the scaffold provide mechanical properties matching the bone. The prototype was tested in a rat model by resecting 5mm long fragments of femur and replacing it with 3D-printed PCL scaffold. Already within 1-week post operation, bone cells migrated into the scaffold from surrounding bone tissue.
BTO AS is the patent estate holder and has the commercialization rights. Between 500,000 and 1.4 million bone grafting procedures take place in the US each year, and ca. 1.3 million in Europe, including non-unions, spinal fusion, bone tumor resections, and hip and knee replacement. Each year there are ca. 165,000 patients in the US and Europe with non-unions eligible for graft and ca. 350,000 bone tumor resections are performed across the US and EU. The ability to use the scaffold in difficult cases of non-union fractures and segmental bone defects is seen by several key opinion leaders in the field of orthopedics as very valuable in light of the limitations of current options. Only for non-union fractures treatment, estimated combined peak sales of the scaffold across the US and EU would be in the range of $50m-$100m.
We are looking for a investors and collaboration partners.
Prototype is ready to be tested in the large animal model. Experiments are planned for second half of 2019 and 2020.
Patent application: PCT/EP2018/056124; priority date March 10, 2017
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