Has Mesentech developed a drug or a device?
Mesentech has developed a bone-targeting drug-conjugate called C3 that contains a small-molecule targeting moiety and small-molecule drug moiety. The conjugate carries the drug in an inactive state until it binds to the bone. After the targeting moiety binds to bone, the drug is released where it is received by stem cells, stimulating their maturation to osteoblasts (bone-making cells).
What is bone remodelling?
Bone remodeling (or bone metabolism) is a lifelong process where mature bone tissue is removed from the skeleton (a process called bone resorption) and new bone tissue is formed (a process called ossification or new bone formation). These processes also control the reshaping or replacement of bone following injuries like fractures but also micro-damage, which occurs during normal activity. Remodeling responds also to functional demands of the mechanical loading and inactivity or lack of loading (like with immobilized patients or in zero gravity in space) can lead to extensive bone loss.An imbalance in the regulation of bone remodeling can result from an imbalance in two sub-processes, bone resorption and bone formation, and can result in many metabolic bone diseases, such as osteoporosis.[From Wikipedia]
How Safe is C3?
Mesentech’s drug-conjugate C3 avoids systemic exposure and side effects by specifically delivering drugs to the bone. C3 is exceptionally well tolerated and expected to be very safe both in terms of acute and chronic toxicity and side effects (formal safety studies are scheduled to start early 2019). This is because the EP4a is carried in bloodstream in an inactive state until it reaches the bone. It is then released slowly and exactly where it is needed.
Is this a bisphosphonate?
No, Mesentech’s drug-conjugate C3 uses a modified alendronic acid as a targeting moiety for its property of high-affinity to bone. It has no biological activity. Mesentech's drugs work through the prostaglandin pathway and are anabolic.