99mTc-Zoledronic Acid is a radiopharmaceutical drug that is used for the scintigraphy of the skeleton. It is based on the latest generation of bisphosphonate, Zoledronic acid. Zoledronic acid is a potent inhibitor of bone resorption and is commonly used in the treatment of osteoporosis, hypercalcemia of malignancy, and skeletal complications in patients with cancer.
When combined with the radioactive isotope technetium-99m (99mTc), Zoledronic acid can be used as a diagnostic tool to detect bone metastases, evaluate bone turnover, and assess various bone diseases. The radiopharmaceutical is injected into the patient, where it accumulates in areas of increased bone turnover, allowing for the detection of abnormalities in the bone through imaging techniques such as single-photon emission computed tomography (SPECT) or positron emission tomography (PET).
Overall, 99mTc-Zoledronic Acid provides clinicians with a non-invasive and effective way to assess bone health and diagnose skeletal disorders, making it a valuable tool in the field of nuclear medicine.
Description
99mTc-Zoledronic acid (99mTc-ZDA; 99mTc-Zoledronate; 99mTc-ZA) is a radiopharmaceutical drug based on the latest generation of bisphosphonate (Zoledronic acid) for the scintigraphy of the skeleton. The molecule was developed at the Mainz University and is patent protected. ITM obtained an exclusive license for development.
Clinical applications
The drug is used for finding centers of pathologic changes of different origin and dissemination in the skeleton: primary and metastatic malignant tumors, osteomelitis, bone-joint tuberculosis, arthritis of different origin, and others.
Availability
99mTc-Zoledronic acid is available from Pharm Sintez under the name 99mTc-Rezoscan and apparently only in Russia.
- Competition
Radiopharmaceutical analogs of 99mTc-Zoledronic acid used for the examination of bones include 99mTc-PyP (pyrophosphate), 99mTc-MDP (medronate), 99mTc-HEDP (etidronate), 99mTc-EDTMP (lexidronam), 99mTc-HDP (oxidronate). 99mTc-ZDA (Zoledronic acid) belongs to the latest generation of bisphosphonates with a claim of a higher affinity to the areas of high metabolism and accelerated resorption in the bone tissue.
In this family of tracers, 68Ga-NODAGA-Zoledronate and 68Ga-DOTA-Zoledronate are also explored, while therapeutics analogues are labeled with 153Sm (153Sm-Zoledronic acid) or 177Lu (177Lu-Zoledronate). Human trials with 177Lu-DOTAZOL have been initiated in July 2015 in South Africa with 177Lu and support provided by ITM and NECSA. Trials with 188Re-Zoledronic acid (188Re-ZA) compared to 89Sr-Strontium Chloride demonstrated efficacy in breast cancer patients.
Comments
The product is only locally available and needs a long way to go before it can be filed for approval outside of Russia. In any case, it will have to confirm the claims and show superiority over the best and most used imaging agent for bone scans which is presently 99mTc-Medronate.