Medroskan, 99mTs (Lyophilisate) Instructions for Use

Marketing Authorization Holder

Diamed, LLC (Russia)

ATC Code

V09BA02 (Technetium (99mTc) medronate)

Active Substance

Technetium [99mTc] (Grouping name)

Dosage Form

Medroskan, 99mTs

Lyophilisate for preparation of solution for intravenous administration

Dosage Form, Packaging, and Composition

Lyophilisate for preparation of solution for intravenous administration

10 mg – vials (5 pcs.) – cardboard packs – for hospitals

Pharmacotherapeutic Group

Diagnostic radiopharmaceuticals; skeletal imaging agents; technetium (99mTc) compounds

Pharmacological Action

When administered in usual doses, this agent does not exhibit pharmacodynamic effects detectable clinically and/or analytically.

Pharmacokinetics

Within the first 3 minutes after injection of technetium [99mTc] medronic acid, it is absorbed by soft tissues and accumulates in the kidneys. As clearance from these organs and tissues increases, progressive accumulation in the skeletal system is observed, initially in the lumbar vertebrae and pelvic area. Blood clearance occurs in 3 phases: 1 – rapid phase (T_1/2 3.5 min), 2 – intermediate phase (T_1/227 min) and 3 – slow phase (T_1/2144 min). The rapid phase represents the transfer of the radioactive substance from the bloodstream to the extravascular system, the intermediate phase includes skeletal uptake. The slow phase is likely associated with the release of the intravenously administered technetium [99mTc] medronic acid complex from the protein-bound complex. Approximately 50% of the administered activity accumulates in the skeleton. Maximum accumulation in bone is reached 1 hour after injection and remains almost constant up to 72 hours. The circulating unbound complex is excreted by the kidneys. The peak activity excreted by the kidneys is reached approximately 20 minutes later. Within 1 hour, with normal renal glomerular filtration function, about 32% of the total amount of the unbound complex is filtered, within 2 hours – 47.5%, and within 6 hours – 60%. The amount of phosphonate in the recommended activity range does not affect renal excretion. The amount excreted through the intestines is insignificant. The degree of accumulation in the skeletal system depends on circulation and the degree of regeneration of the underlying bone material. Retention in the body is 31.6±5% in healthy individuals, 38.2±7% in individuals with extensive metastases, 49±11% in primary hyperparathyroidism, and 45% in osteoporosis.

Indications

For conducting scintigraphic studies of the skeletal system to identify areas of altered osteogenesis associated with the following diseases and conditions: neoplasms – establishing the stage of spread of osteosarcoma, detection and subsequent monitoring of bone metastases; non-tumor lesions – as an additional research method in the assessment of osteomyelitis, avascular necrosis, Paget’s disease, stress fractures, shin splint syndrome, screening for prosthesis failure or infection when X-ray results are inconclusive, reflex sympathetic dystrophy syndrome, bone graft viability;

Work with radioactive substances must be carried out in accordance with the Basic Sanitary Rules for Ensuring Radiation Safety, Radiation Safety Standards and methodological guidelines Hygienic requirements for ensuring radiation safety during radionuclide diagnostics using radiopharmaceuticals.

ICD codes

Dosage Regimen

Adults: the optimal activity when administering this agent may vary depending on patient characteristics, the type of diagnostic task, and the technical characteristics of the imaging equipment. According to the recommendations of the European Association of Nuclear Medicine, the average activity for a single intravenous injection is 500 MBq (300-740 MBq). However, adjustment of the activity value may be justified. According to the recommendations of the European Association of Nuclear Medicine, for adult patients with severe obesity, an activity of up to 11-13 MBq/kg may be required for intravenous administration only.

In children and adolescents, the amount of the drug administered should be adapted to the patient’s body weight.

It is strictly necessary to avoid accidental entry of this agent into the surrounding tissues during intravenous administration to prevent their radiation damage.

Adverse Reactions

Immune system disorders very rarely – hypersensitivity reactions, vasculitis, erythema multiforme, life-threatening anaphylaxis 8-48 hours after administration.

Nervous system disorders very rarely – headache.

Cardiovascular system disorders very rarely – drop in blood pressure and symptoms of arterial hypotension, dilation of subcutaneous vessels.

Respiratory system disorders very rarely – cough.

Gastrointestinal system disorders very rarely – nausea, vomiting.

Hepatobiliary disorders very rarely – jaundice.

Skin and subcutaneous tissue disorders very rarely – local or generalized rash with itching and skin irritation. Disorders of the skin and subcutaneous tissues

Musculoskeletal and connective tissue disorders very rarely – chills, arthralgia, myalgia.

Renal and urinary disorders: very rarely – oliguria.

General disorders and administration site conditions very rarely – fever, malaise

Other exposure to ionizing radiation is associated with the occurrence of cancer, as well as the possibility of hereditary defects. The effect of the radiation dose resulting from exposure to the radioactive substance may lead to an increased frequency of cancer and mutations. Therefore, in each case, it is necessary to ensure that the risk of harm to the patient’s body from radiation during the study is lower than that from the disease itself. Since the effective dose is 2.85 mSv (for a person with a body weight of 70 kg) at the average recommended activity of 500 MBq, the probability of these adverse events is expected to be low.

Contraindications

Hypersensitivity to any substance included in the composition of the drug used; breastfeeding.

Use in Pregnancy and Lactation

Before administering radiopharmaceuticals to a woman of childbearing age, it is necessary to determine the presence or absence of pregnancy. Radiation doses during radionuclide studies performed on pregnant women also affect the fetus. Therefore, during pregnancy, only necessary studies should be performed when the probable benefit of the study significantly outweighs the risk to the mother and fetus.

If administration is deemed necessary, breastfeeding should be interrupted for 12 hours and feeding with expressed milk should be avoided.

Close contact with the infant should be limited during this time.

Use in Hepatic Impairment

Correction of the administered activity of this agent for patients with hepatic insufficiency is not required.

Use in Renal Impairment

The need for dose adjustment in patients with renal failure has not been specifically studied.

Pediatric Use

The activity value when using the radioactive agent in children and adolescents is calculated individually, based on clinical needs and assessment of the risk-benefit ratio in this patient group. Indications for the diagnostic study must be carefully analyzed, as the effective dose (mSv/MBq) is higher than in adults. Special attention should be paid to the relatively higher radiation exposure to the epiphyses of growing bone.

Geriatric Use

Decreased renal function and decreased osteogenesis in elderly individuals may affect the absorption, distribution, or excretion of this substance from the body.

Special Precautions

It is recommended to perform three-phase bone scintigraphy (assessment of blood flow, determination of blood volume in the pathological focus, and conventional delayed images), which has higher sensitivity and specificity in detecting osteomyelitis or other diseases compared to single-phase delayed study protocols.

Caution should be exercised when diagnosing a failed or infected prosthesis in the immediate postoperative period for several months after surgery. As with scintigraphic diagnosis of osteomyelitis and other diseases, performing three-phase bone scintigraphy is strongly recommended.

Caution is required when interpreting the results of bone scintigraphy performed within several months after radiation and specific drug therapy for oncological diseases. During this time interval, increased intensity of drug accumulation in bone tissue, in previously identified lesions, may not reflect the process of disease progression or lack of treatment efficacy, but rather be a responsive “flare” due to a favorable reparative process of osteoblasts, secondary to successfully conducted treatment.

In case of hypersensitivity reactions or anaphylactic reactions, the administration of this agent should be stopped immediately and specific treatment initiated, intravenously if necessary. To ensure immediate therapeutic measures in emergency situations, necessary medications and equipment, such as an endotracheal tube and a ventilator, must always be readily available.

After the study procedure, the patient should limit close communication with infants and pregnant women for 12 hours.

Drug Interactions

Increased extraosseous accumulation of the radiopharmaceutical has been reported with the use of iron-containing compounds, single-dose diphosphonate, some cytotoxic and immunosuppressive drugs, aluminum-containing antacids, radiocontrast agents, antibiotics, anti-inflammatory drugs, intravenous administration of calcium gluconate, calcium heparin, and gamma-aminocaproic acid. Since etidronic acid inhibits the absorption of medronic acid by bone tissue, bone scintigraphy should be performed no earlier than 2-4 weeks after the administration of etidronic acid.

Storage Conditions

Store at 2°C (36°F) to 8°C (46°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.