Samarium, 153SM oxabifor (Solution) Instructions for Use

Marketing Authorization Holder

L.Ya. Karpov NIHCHP, JSC (Russia)

ATC Code

V10BX02 (Samarium (153Sm) lexidronam)

Dosage Form

Samarium, 153SM Oxabifor

Solution for intravenous administration 240-1500 MBq: 500, 1000 or 2000 MBq fl.

Dosage Form, Packaging, and Composition

Solution for intravenous administration colorless, transparent.

Excipients: sodium chloride, water for injections.

500 MBq – Vials with a capacity of 15 ml (1) – packaging kit for radioactive substances.
1000 MBq – Vials with a capacity of 15 ml (1) – packaging kit for radioactive substances.
2000 MBq – Vials with a capacity of 15 ml (1) – packaging kit for radioactive substances.

Clinical-Pharmacological Group

Radiopharmaceutical drug for the palliative treatment of bone metastases

Pharmacotherapeutic Group

Radiopharmaceutical therapeutic agent

Pharmacological Action

The drug Samarium, ¹⁵³Sm oxabifor has the ability to selectively accumulate in metastatic and inflammatory-destructive foci in bone tissue.

Due to the content of the radionuclide Samarium-153, which emits beta particles, the drug acts on the cells of the metastatic or inflammatory focus and the surrounding nerve endings, simultaneously causing an analgesic and antiproliferative effect.

The presence of gamma radiation allows the distribution and accumulation of the drug in the body to be recorded using a gamma camera.

According to subsequent osteoscintigraphy with samarium-153, accumulation of the drug in the lesions is recorded as 2-3 times or more higher than in symmetrical areas of healthy tissue.

These data usually correspond to the results of diagnostics with osteotropic compounds ^99mTc, which is why it can be used as a selection criterion for radionuclide therapy with the drug Samarium, ¹⁵³Sm oxabifor.

Pharmacokinetics

After intravenous administration of Samarium, ¹⁵³Sm oxabifor, it accumulates in the kidneys and bladder during the first two hours, with slight uptake of the drug in the liver and the projection of the nasal sinuses.

After 2 hours, it begins to be fixed in the bones, mainly in the affected areas (metastatic foci, inflammation zones, sites of previous fractures).

During the first day, the accumulation of the drug in bone tissue increases with predominant localization in the aforementioned foci.

After fixation in bone foci, the decrease in activity occurs mainly due to physical decay, although in isolated cases, an increase in the relative accumulation of the drug in individual foci may be observed during the first 3 days due to redistribution.

Within the first two days, 28% to 42% of the administered activity is excreted in the urine.

The maximum excretion occurs during the first 8-12 hours.

The level of excretion depends on kidney function, the volume of bone lesions, and the activity of drug fixation in the foci.

Indications

The drug Samarium, ¹⁵³Sm oxabifor is used in adults.

• In oncological practice for the persistent reduction of pain intensity caused by metastatic bone lesions, as well as to inhibit the growth of metastatic tissue in bone foci;
• In rheumatological practice for the persistent reduction of arthralgias in chronic diseases of the musculoskeletal system accompanied by severe pain (rheumatoid arthritis, deforming arthrosis, etc.).

ICD codes

Dosage Regimen

The drug is administered intravenously.

To reduce the radiation exposure to personnel and ensure safety during the procedure, it is advisable to use the method of preliminary dilution in 50-100 ml of saline.

For this, it is recommended to set up a system for intravenous infusions and start a drip infusion of saline.

Then, after temporarily clamping the tube of the system with a clamp, the entire required amount of Samarium, ¹⁵³Sm oxabifor solution should be injected into the vial with saline, after which the intravenous drip infusion should be continued.

In oncological practice, it is recommended to use an activity calculated as 1.5 mCi/kg of the patient’s body weight.

In some cases, it can be increased to 2.0 mCi/kg or reduced to 1.0 mCi/kg of body weight.

In rheumatological practice, it is recommended to use an activity calculated as 0.5 mCi/kg of body weight.

If indicated, the drug can be administered again after 3 months.

Radiation exposure to the patient’s organs and tissues when using the drug Samarium, ¹⁵³Sm oxabifor

Whole body (Effective equivalent dose (mSv/MBq)) 0.01161

Adverse Reactions

No reactions or side effects were recorded directly during the administration and in the first hours after it.

Within the first three days, minor toxic reactions in the form of nausea are possible, which resolve on their own or are relieved by taking 1-2 tablets of Cerucal (metoclopramide).

Within the first two weeks, an increase in pain is possible due to the radiation reaction of tissues in the lesions.

The exacerbation can be relieved by taking analgesics and (or) anti-inflammatory drugs.

The clinical effect usually appears after two weeks.

It is persistent (over 3 months, and in some patients – over 6 months after a single administration).

Contraindications

• Hypersensitivity to the drug or its components;
• Severe renal and/or hepatic insufficiency;
• Low platelet count (below 100.0×10⁹/L);
• Low white blood cell count (below 2.0×10⁹/L);
• Progressive decrease in the number of blood cells;
• Prior massive myelosuppressive chemotherapy;
• Threat of spinal compression fracture.

Use in Pregnancy and Lactation

The use of the drug is contraindicated during pregnancy and breastfeeding.

Use in Hepatic Impairment

The drug is contraindicated in severe hepatic insufficiency.

Use in Renal Impairment

The drug is contraindicated in severe renal insufficiency.

Pediatric Use

The drug is contraindicated in children under 18 years of age.

Special Precautions

The drug can be used in specialized medical institutions that have additional treatment facilities or in regional oncology dispensaries, provided that urine is collected during the first two days after administration with subsequent holding for radionuclide decay.

Work with the drug must be carried out in accordance with the “Basic Sanitary Rules for Ensuring Radiation Safety” (OSPORB-99), “Radiation Safety Standards” (NRB-99), Methodological Guidelines “Hygienic Requirements for Ensuring Radiation Safety during Radionuclide Diagnostics using Radiopharmaceuticals” (MU-2.6.1.1892-04).

Overdose

There are no data on drug overdose.

Drug Interactions

Radionuclide therapy with Samarium, ¹⁵³Sm oxabifor can be combined with chemotherapy and hormone therapy, while monitoring the general condition of the patient and peripheral blood counts (see Contraindications).

Storage Conditions

Store in accordance with the “Basic Sanitary Rules for Ensuring Radiation Safety” (OSPORB-99) and “Radiation Safety Standards” (NRB-99).

Shelf Life

Shelf life – 4 days from the date and time of manufacture.

Dispensing Status

Not for sale through the pharmacy network. The drug is dispensed upon requests only to specialized radioisotope laboratories of medical diagnostic institutions.

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.