After clinical trials demonstrated a 25% response rate in patients with multiple myeloma (MM), selinexor (Xpovio®) received initial, accelerated U.S. Food and Drug Administration approval in 2019.

Category/Class

Oral targeted agent, nuclear export inhibitor

Mechanism of Action

Selinexor inhibits the export of tumor suppressor proteins, growth regulators, and mRNAs of oncogenic proteins from the nucleus of the cancer cell. The materials accumulate within the nucleus of the cell, leading to cell cycle arrest and apoptosis.

Indication

Used in combination with bortezomib and dexamethasone or with dexamethasone alone for the treatment of adults with MM. Used for the treatment of adults with relapsed or refractory diffuse large B-cell lymphoma (DLBCL).

Dosing

For MM, patients take 100 mg on day 1 of each week in combination with bortezomib and dexamethasone or 80 mg on days 1 and 3 of each week in combination with dexamethasone alone. For DLBCL, patients take 60 mg on days 1 and 3 of each week. Selinexor is dispensed as 20 mg tablets.

Administration

Take by mouth at the same time each day with a full glass of water. Do not crush, chew, or split tablets.

Adverse Reactions

More than 20% of patients in the drug’s clinical trials experienced bone marrow suppression, thrombocytopenia, and neutropenia (with potential for infection), fatigue, nausea, vomiting, diarrhea, anorexia, weight loss, and hyponatremia. Selinexor is associated with a risk of neurologic toxicity, cataracts, and embryo-fetal toxicity.

Nursing Considerations

Verify patients’ pregnancy status prior to initiating treatment. Monitor their complete blood counts with differential, blood chemistry, weight, nutritional status, and volume status at baseline and throughout treatment as clinically indicated. Monitor patients more frequently during their first three months of treatment.

Patients may need to take an antiemetic before their daily treatment. Monitor them for dehydration, and provide IV fluids as needed. Dose adjustment may be required to manage side effects.

Patient Education

Maintain adequate fluid and caloric intake throughout treatment. Take the tablets whole, and do not break, chew, crush or split the pills. If you missed, delayed, or vomited a dose, do not take another dose; wait and take your next dose at your regularly scheduled time. Because selinexor carries a risk of embryo-fetal toxicity, avoid pregnancy and breastfeeding during treatment and for one week after your final dose.

Get a comprehensive patient education sheet.

Special Populations

The drug’s clinical trials demonstrated no difference in effectiveness in patients older than 65 compared to younger patients. Patients older than 75 had a higher incidence of drug discontinuation because of side effects. Safety and efficacy have not been determined in pediatric patients.

Safe Handling

Selinexor is considered a hazardous drug because of it can cause embryo-fetal toxicity.

Patient Assistance

Visit the KaryForward patient support program or call 877-527-9493.