Drug Interactions between samarium sm 153 lexidronam and Vyxeos

GENERALLY AVOID: Theoretical concerns exist that chemotherapeutic agents and other bone marrow depressants may potentiate the myelosuppressive effects of samarium sm 153 lexidronam. In clinical trials, white blood cell and platelet counts decreased to a nadir of approximately 40% to 50% of baseline in 95% of patients within three to five weeks after administration of samarium sm 153 lexidronam, and tended to return to pretreatment levels by eight weeks. The potential for additive bone marrow toxicity with myelotoxic treatments including chemotherapy or external beam radiation has not been studied.

MANAGEMENT: The manufacturer recommends avoiding concomitant use of samarium sm 153 lexidronam with chemotherapy or external beam radiation therapy unless benefits are anticipated to outweigh the risks. Moreover, samarium sm 153 lexidronam should not be given after either of these treatments until there has been time for adequate marrow recovery. Caution and close monitoring of bone marrow function are advisable if coadministration with other myelotoxic agents is required. Patients should be advised to contact their physician if they develop signs and symptoms of myelosuppression such as pallor, dizziness, fatigue, lethargy, fainting, unusual bleeding or bruising, or signs of infection such as fever, chills, diarrhea, sore throat, muscle aches, shortness of breath, blood in phlegm, weight loss, red or inflamed skin, body sores, and pain or burning during urination.

MONITOR: The concomitant or sequential administration of multiple antineoplastic agents may result in additive toxicities, particularly in the bone marrow, gastrointestinal tract and heart.

MANAGEMENT: Close clinical and laboratory monitoring for hematologic and nonhematologic toxicities are recommended when antineoplastic agents are administered concurrently or during close intervals. Dosing adjustments may be necessary. The manufacturers' recommendations and institutional protocols for dosage, treatment regimens, monitoring, and management of toxicities should be consulted.