Anticipatory Management, Adherence Strategies Optimize MM Treatment With Selinexor

Discussing a treatment regimen with a patient.
Discussing a treatment regimen with a patient.

Optimal supportive care that includes patient education and anticipatory management of common adverse effects (AE) can improve adherence to treatment protocols and result in better response rates in patients receiving selinexor for relapsed/refractory multiple myeloma (MM). These findings were demonstrated in an adverse effect (AE) management protocol presented during the Oncology Nursing Society (ONS) Bridge, a virtual conference.

Multiple myeloma (MM) is the second most common hematologic cancer. In July 2019, the U.S. Food and Drug Administration (FDA) granted accelerated approval to selinexor in combination with dexamethasone for adult patients with relapsed or refractory multiple myeloma who have received at least 4 prior therapies and whose disease was refractory to at least 2 immunomodulatory agents, at least 2 proteasome inhibitors, and an anti-CD38 monoclonal antibody. Approval was based on data from the STORM protocol (ClinicalTrials.gov Identifier: NCT02336815).

Selinexor is an oral small molecule therapy that inhibits exportin1 (XPO1)-mediated nuclear export of tumor suppressor proteins and oncogenic mRNAs involved in cancer-cell growth. The recommended dose is selinexor 80 mg oral and dexamethasone 20 mg oral on days 1, 3, 8, 10, 15, 17, 22, and 24 of a 28-day cycle.

In this poster presentation, Erika Florendo, RN, ANP-BC, and colleagues discussed the supportive care measures and strategies used at Mt Sinai Hospital (MSH) in New York, New York, to improve tolerability and increase response rates.

Commonly reported adverse effects (AEs) of selinexor include nausea, anorexia, fatigue, thrombocytopenia, and hyponatremia. Of the123 patients enrolled in STORM Part 2, 28 were treated at MSH and demonstrated longer overall response rates (53.6% in MSH vs 26.2% in overall STORM population) and fewer discontinuations due to AEs (3.7% vs 18.8%).

Patients treated at MSH received the following prophylactic medications: ondansetron 8 mg orally 3 times a day, olanzapine 2.5 mg orally daily at night, and rolapitant 180 mg orally every 2 weeks.

In addition, patients were given intravenous (IV) fluids 1 to 3 times a week, as needed, and referred for a nutritional consult at baseline and at regular intervals. Daily oral methylphenidate at a dose of 10 mg was administered to relieve fatigue that was unresponsive to selinexor dose modifications.

Thrombocytopenia was mitigated with platelet transfusions and romiplostim 10 mcg/kg subcutaneously weekly on selinexor off days. Hyponatremia was treated aggressively with IV fluids and sodium chloride 1 g orally 3 times a day.

Additional strategies used to improve adherence included providing a medication diary and a calendar for tracking appointments, involving social work, and educating both the patient and the caregiver regarding medications and antiemetic schedules. Anticipatory guidance and implementing a day 3 phone call to ensure adherence to medication schedule and to discuss potential adverse effects were also effective. Finally, a visiting nurse may be needed to help patients with medication administration and polypharmacy.

“Optimization of supportive care and oral adherence is critical to maintain patients on treatment longer to get better response rates in this triple class refractory population,” Ms Florendo concluded. She went on to recommend that oncology nurses focus patient education on common AEs and necessary evaluation/supportive care measures.

Reference

Florendo E, Mancia IS, Thomas J. Symptom management for patients with relapsed and refractory multiple myeloma receiving therapy with selinexor (Xpovio™). Presentation at: Oncology Nursing Society (ONS) Bridge; September 8-17, 2020. Accessed September 19, 2020. https://ons.confex.com/ons/2020/ap/eposter.cgi?eposterid=1046