Xpovio (selinexor)

What Is Xpovio (Selinexor)?

XPOVIO® (selinexor) is the first and only medication in the drug class known as selective inhibitor of nuclear export (SINE) that has been approved to treat myeloma by the FDA. Xpovio works by preventing myeloma cells from expelling tumor suppressor proteins that help protect the cells from cancer, thereby interfering with myeloma cell growth.

How Is Xpovio Used and Who Is a Candidate to Receive It?

Xpovio is used in multiple myeloma in both early relapse and late relapse settings. 

FDA approval of Xpovio

In 2019, Xpovio was granted accelerated approval by the FDA for use in combination with the steroid dexamethasone [Xd] for the treatment of adult patients with relapsed or refractory multiple myeloma (RRMM) who have received at least 4 prior therapies and whose disease is refractory to at least 2 proteasome inhibitors, at least 2 immunomodulatory agents, and an anti-CD38 monoclonal antibody. This FDA approval was based on data from Part 2 of the STORM phase IIb clinical trial, and Xpovio was initially given on a twice weekly schedule (starting with a dose of 80 mg).

In 2020, the FDA approved Xpovio in combination with Velcade® (bortezomib) plus dexamethasone [XVd] for myeloma patients who have received at least 1 prior therapy. This FDA approval was based on data from the BOSTON phase III randomized clinical trial, and Xpovio was initially given on a once-weekly schedule (starting with a dose of 100 mg).

Xpovio in NCCN Guidelines

The National Comprehensive Cancer Network (NCCN) Guidelines list additional treatment options based on the STORM, BOSTON, and STOMP studies: 

• For early relapse (after 1–3 prior therapies), XVd once-weekly.
• Useful in certain circumstances (based on the STOMP clinical trial)
  • After 1 or more prior lines of therapy, proteasome inhibitor Kyprolis® (carfilzomib) plus Xd [XKd] once-weekly with Xpovio dosing starting at 80 mg.
  • After 2 or more prior lines of therapy, immunomodulatory agent Pomalyst® (pomalidomide) plus Xd [XPd] once-weekly with Xpovio dosing starting at 60 mg.
  • After 3 or more prior lines of therapy, either the intravenous (IV) Darzalex® (daratumumab) or the subcutaneous (SQ) Darzalex Faspro® (daratumumab plus hyaluronidase-fihj) monoclonal antibody plus Xd [known as XDd, DXd, or Dara-Xd] once-weekly with Xpovio dosing starting at 100 mg.
• For late relapse (after 4 or more prior therapies), Xd twice-weekly with Xpovio dosing starting at 80 mg.
  Your doctor may opt to start you on Xpovio at a dose as low as 40 mg, and may recommend one or more additional dose modifications.
   

How Is Xpovio Taken?

Xpovio is a medication taken by mouth in the form of a tablet. Swallow the tablet whole with water. Do not break, chew, crush, or divide the tablets. Each Xpovio tablet should be taken at approximately the same time of day. 

Your doctor will monitor your complete blood count (CBC) and body weight before you start Xpovio and as needed during treatment. 

Your doctor will prescribe medication for nausea and vomiting to be taken before and during treatment with Xpovio. You must take this medication as prescribed by your doctor, even if you’re not experiencing any nausea or vomiting. If you have any questions or concerns about your prescribed medication, discuss this with your doctor. 

Throughout your treatment with Xpovio, it is very important to maintain good intake of food and fluids. If necessary, you may receive IV fluids to prevent or treat dehydration

Warnings and Precautions When Taking Xpovio

Thrombocytopenia: Monitor platelet counts throughout treatment. Manage with dose interruption and/or reduction and supportive care.

Neutropenia: Monitor neutrophil counts throughout treatment. Manage with dose interruption and/or reduction and granulocyte colony-stimulating factors.

Gastrointestinal Toxicity: Nausea, vomiting, diarrhea, anorexia, and weight loss may occur. Provide antiemetic prophylaxis. Manage with dose interruption and/or reduction, antiemetics, and supportive care.

Hyponatremia: Monitor serum sodium levels throughout treatment. Correct for concurrent hyperglycemia and high serum paraprotein levels. Manage with dose interruption, reduction, or discontinuation, and supportive care.

Serious Infection: Monitor for infection and treat promptly.

Neurological Toxicity: Advise patients to refrain from driving and engaging in hazardous occupations or activities until neurological toxicity resolves. Optimize hydration status and concomitant medications to avoid dizziness or mental status changes.

Embryo-Fetal Toxicity: Xpovio can cause fetal harm. Advise females of reproductive potential and males with a female partner of reproductive potential of the potential risk to a fetus and to use effective contraception.

Cataract: Cataracts may develop or progress. Treatment of cataracts usually requires surgical removal of the cataract

Possible Side Effects of Xpovio

Side effects of Xpovio can be prevented or managed well with dose reductions, dose interruptions, or other supportive care. Common side effects include:

• nausea
• thrombocytopenia (low level of platelets)
• fatigue
• anemia (low level of red blood cells)
• decreased appetite
• diarrhea
• vomiting
• hyponatremia (low level of sodium in the blood)
• neutropenia (low level of neutrophils, a type of white blood cell)
• lymphopenia (low level of lymphocytes, a type of white blood cell)
• peripheral neuropathy
• hypophosphatemia (low level of phosphorus in the blood)
• decreased weight
• cataract
• constipation
• dyspnea (shortness of breath)
• upper respiratory tract infection

Support

Please visit Karyforward.com or call KayForward Patient Support by Karyopharm at 1-877-KARY4WD.