1.1 Multiple Myeloma

• XPOVIO in combination with bortezomib and dexamethasone is indicated for the treatment of adult patients with multiple myeloma who have received at least one prior therapy.
• XPOVIO in combination with dexamethasone is indicated for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, at least two immunomodulatory agents, and an anti-CD38 monoclonal antibody.

1.2 Diffuse Large B-Cell Lymphoma

XPOVIO is indicated for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), not otherwise specified, including DLBCL arising from follicular lymphoma, after at least 2 lines of systemic therapy.

This indication is approved under accelerated approval based on response rate [see Clinical Studies (14.2)]. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).

2.1 Recommended Dosage for Multiple Myeloma

In Combination with Bortezomib and Dexamethasone (XVd)

The recommended dosage of XPOVIO is 100 mg taken orally once weekly on Day 1 of each week until disease progression or unacceptable toxicity in combination with:

• Bortezomib 1.3 mg/m2 administered subcutaneously once weekly on Day 1 of each week for 4 weeks followed by 1 week off.
• Dexamethasone 20 mg taken orally twice weekly on Days 1 and 2 of each week.

Refer to Clinical Studies (14.1) and the prescribing information of bortezomib and dexamethasone for additional dosing information.

2.2 Recommended Dosage for Diffuse Large B-Cell Lymphoma

The recommended dosage of XPOVIO is 60 mg taken orally on Days 1 and 3 of each week until disease progression or unacceptable toxicity.

2.3 Recommended Monitoring for Safety

Monitor complete blood count (CBC) with differential, standard blood chemistries, body weight, nutritional status, and volume status at baseline and during treatment as clinically indicated. Monitor more frequently during the first three months of treatment [see Warning and Precautions (5.1, 5.2, 5.3, and 5.4)]. Assess the need for dosage modifications of XPOVIO for adverse reactions [see Dosage and Administration (2.5)].

2.4 Recommended Concomitant Treatments

Advise patients to maintain adequate fluid and caloric intake throughout treatment. Consider intravenous hydration for patients at risk of dehydration [see Warnings and Precautions (5.3, 5.4)].

Provide prophylactic antiemetics. Administer a 5-HT3 receptor antagonist and other anti-nausea agents prior to and during treatment with XPOVIO [see Warnings and Precautions (5.3)].

2.5 Dosage Modification for Adverse Reactions

Recommended XPOVIO dosage reduction steps are presented in Table 1.

Recommended dosage modifications for hematologic adverse reactions in patients with multiple myeloma and DLBCL are presented in Table 2 and Table 3, respectively. Recommended dosage modifications for nonhematologic adverse reactions are presented in Table 4.

2.6 Administration

Each XPOVIO dose should be taken at approximately the same time of day and each tablet should be swallowed whole with water. Do not break, chew, crush, or divide the tablets.

If a dose of XPOVIO is missed or delayed, instruct patients to take their next dose at the next regularly scheduled time.

If a patient vomits a dose of XPOVIO, the patient should not repeat the dose and the patient should take the next dose on the next regularly scheduled day.

5.1 Thrombocytopenia

XPOVIO can cause life-threatening thrombocytopenia, potentially leading to hemorrhage. Thrombocytopenia is the leading cause of dosage modifications [see Adverse Reactions (6.1)].

In patients with multiple myeloma who received XPOVIO 100 mg once weekly (BOSTON, n=195), thrombocytopenia was reported in 92% of patients and severe (Grade 3-4) thrombocytopenia was reported in 43% of patients. The median time to first onset was 22 days for any grade thrombocytopenia and 43 days for Grade 3 or 4 thrombocytopenia. Bleeding occurred in 16% of patients with thrombocytopenia, clinically significant bleeding (Grade ≥3 bleeding) occurred in 4% of patients with thrombocytopenia, and fatal hemorrhage occurred in 2% of patients with thrombocytopenia. Permanent discontinuations of XPOVIO due to thrombocytopenia occurred in 2% of patients.

In patients with multiple myeloma who received XPOVIO 80 mg twice weekly (STORM, n=202), thrombocytopenia was reported as an adverse reaction in 74% of patients and severe (Grade 3-4) thrombocytopenia was reported in 61% of patients. The median time to onset of the first event was 22 days. Bleeding occurred in 23% of patients with thrombocytopenia, clinically significant bleeding occurred in 5% of patients with thrombocytopenia, and fatal hemorrhage occurred in <1% of patients.

In patients with DLBCL who received XPOVIO 60 mg twice weekly (SADAL, n=134), thrombocytopenia developed or worsened in 86% of patients, including Grade 3-4 thrombocytopenia in 49% of patients (Grade 4, 18%). The median time to first onset was 28 days for any grade thrombocytopenia and 33 days for Grade 3 or 4 thrombocytopenia.

Monitor platelet counts at baseline and throughout treatment. Monitor more frequently during the first three months of treatment. Institute platelet transfusion and/or other treatments as clinically indicated. Monitor patients for signs and symptoms of bleeding and evaluate promptly. Interrupt, reduce dose, or permanently discontinue based on severity of adverse reaction [see Dosage and Administration (2.5)].

5.2 Neutropenia

XPOVIO can cause life-threatening neutropenia, potentially increasing the risk of infection [see Adverse Reactions (6.1)].

In patients with multiple myeloma who received XPOVIO 100 mg once weekly (BOSTON, n=195), neutropenia was reported in 48% of patients and severe neutropenia (Grade 3-4) was reported in 12% of patients. The median time to onset of the first event was 23 days for any grade neutropenia and 40 days for Grade 3-4 neutropenia. Febrile neutropenia was reported in <1% of patients.

In patients with multiple myeloma who received XPOVIO 80 mg twice weekly (STORM, n=202), neutropenia was reported as an adverse reaction in 34% of patients and severe (Grade 3-4) neutropenia was reported in 21% of patients. The median time to onset of the first event was 25 days. Febrile neutropenia was reported in 3% of patients.

In patients with DLBCL (SADAL, n=134), Grade 3 neutropenia developed in 21% of patients and Grade 4 neutropenia developed in 9% of patients. The median time to first onset of Grade 3 or 4 neutropenia was 32 days. Febrile neutropenia was reported in 3% of patients.

Obtain white blood cell counts with differential at baseline and throughout treatment. Monitor more frequently during the first three months of treatment. Monitor patients for signs and symptoms of concomitant infection and evaluate promptly. Consider supportive measures, including antimicrobials and growth factors (e.g., G-CSF). Interrupt, reduce dose or permanently discontinue based on severity of adverse reaction [see Dosage and Administration (2.5)].

5.3 Gastrointestinal Toxicity

XPOVIO can cause severe gastrointestinal toxicities [see Adverse Reactions (6.1)]. In patients with DLBCL (n=134), gastrointestinal toxicity occurred in 80% of patients with Grade 3 or 4 in 13%.

5.4 Hyponatremia

XPOVIO can cause severe or life-threatening hyponatremia [see Adverse Reactions (6.1)].

In patients with multiple myeloma who received XPOVIO 100 mg once weekly (BOSTON, n=195), hyponatremia was reported in 58% of patients and Grade 3-4 hyponatremia was reported in 14% of patients. The median time to first onset was 21 days for any grade hyponatremia and the median time to first onset for Grade 3 or 4 hyponatremia was 22 days.

In patients with multiple myeloma who received XPOVIO 80 mg twice weekly (STORM, n=202), hyponatremia was reported as an adverse reaction in 39% of patients and Grade 3 or 4 hyponatremia was reported in 22% of patients. The median time to onset of the first event was 8 days.

In patients with DLBCL (SADAL, n=134), hyponatremia developed in 62% of patients and Grade 3 hyponatremia developed in 16% of patients treated with XPOVIO. In approximately 63% of cases, hyponatremia occurred in the context of gastrointestinal toxicity such as nausea, vomiting, diarrhea, dehydration, and anorexia.

Monitor sodium level at baseline and throughout treatment. Monitor more frequently during the first two months of treatment. Correct sodium levels for concurrent hyperglycemia (serum glucose >150 mg/dL) and high serum paraprotein levels. Assess hydration status and manage hyponatremia per clinical guidelines, including intravenous saline and/or salt tablets as appropriate and dietary review. Interrupt, reduce dose or permanently discontinue based on severity of the adverse reaction [see Dosage and Administration (2.5)].

5.5 Serious Infection

XPOVIO can cause serious and fatal infections. Most of these infections were not associated with Grade 3 or higher neutropenia [see Adverse Reactions (6.1)].

In patients with multiple myeloma who received XPOVIO 100 mg once weekly (BOSTON, n=195), 69% of patients experienced any grade of infection. Grade ≥3 infections were reported in 32% of patients, and deaths from infections occurred in 3.1% of patients. The most frequently reported Grade ≥3 infection was pneumonia in 14% of patients, followed by sepsis in 4.1% and upper respiratory tract infection in 3.6% of patients.

In patients with multiple myeloma who received XPOVIO 80 mg twice weekly (STORM, n=202), 52% of patients experienced any grade of infection. Grade ≥3 infections were reported in 25% of patients, and deaths from infections occurred in 4% of patients within 30 days of last treatment. Upper respiratory tract infection of any grade occurred in 21%, pneumonia in 13%, and sepsis in 6% of patients. The most frequently reported Grade ≥3 infections were pneumonia in 9% of patients, followed by sepsis in 6%. The median time to onset was 54 days for pneumonia and 42 days for sepsis.

In patients with DLBCL (SADAL, n=134), 25% of patients experienced Grade 3 or higher infection and 21% had an infection-related serious adverse reaction; 49% developed an infection of any grade, most frequently involving the upper or lower respiratory tract. The most frequently reported Grade ≥3 infections were lower respiratory tract infections in 9% of patients (including pneumonia in 6%), followed by sepsis (6%). The median time to onset of Grade ≥3 infection was 42 days.

Atypical infections reported after XPOVIO include, but are not limited to, fungal pneumonia and herpes virus infection.

Monitor for signs and symptoms of infection, evaluate and treat promptly.

5.6 Neurological Toxicity

XPOVIO can cause life-threatening neurological toxicities [see Adverse Reactions (6.1)].

In patients with multiple myeloma who received XPOVIO 100 mg once weekly (BOSTON, n=195), neurological adverse reactions (excluding peripheral neuropathy) including dizziness, syncope, depressed level of consciousness, vertigo, amnesia, and mental status changes (including delirium and confusional state) occurred in 26% of patients and severe events (Grade 3-4) occurred in 3.6% of patients. The median time to the first event was 29 days. Permanent discontinuation due to neurological adverse reactions occurred in 2.1% of patients.

In patients with multiple myeloma who received XPOVIO 80 mg twice weekly (STORM, n=202), neurological adverse reactions, including dizziness, syncope, depressed level of consciousness, and mental status changes (including delirium and confusional state) occurred in 30% of patients and severe events (Grade 3-4) occurred in 9% of patients. The median time to the first event was 15 days.

In patients with DLBCL (SADAL, n=134), neurological adverse reactions occurred in 25% of patients and severe events (Grade 3-4) occurred in 6% of patients treated with XPOVIO. The most frequent manifestations were dizziness (16%) and mental status changes (11%), including confusion, cognitive disorders, somnolence, hallucination, delirium, and depressed level of consciousness. Syncope occurred in 2.2% of patients. The median time to the first event was 28 days. Among patients with such neurological adverse reactions, 68% recovered with a median time to recovery of 14 days.

Coadministration of XPOVIO with other products that cause dizziness or mental status changes may increase the risk of neurological toxicity.

Advise patients to refrain from driving and engaging in hazardous occupations or activities, such as operating heavy or potentially dangerous machinery, until the neurological toxicity fully resolves. Optimize hydration status, hemoglobin level, and concomitant medications to avoid exacerbating dizziness or mental status changes. Institute fall precautions as appropriate.

5.7 Embryo-Fetal Toxicity

Based on data from animal studies and its mechanism of action, XPOVIO can cause fetal harm when administered to a pregnant woman. Selinexor administration to pregnant animals during organogenesis resulted in structural abnormalities and alterations to growth at exposures below those occurring clinically at the recommended dose.

Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential and males with a female partner of reproductive potential to use effective contraception during treatment with XPOVIO and for 1 week after the last dose [see Use in Specific Populations (8.1, 8.3)].

5.8 Cataract

New onset or exacerbation of cataract has occurred during treatment with XPOVIO [see Adverse Reactions (6.1)]. In patients with multiple myeloma who received XPOVIO 100 mg once weekly (BOSTON, n=195), the incidence of new onset or worsening cataracts requiring clinical intervention was reported in 22% of patients. The median time to new onset of cataract was 228 days and was 237 days for worsening of cataract in patients presenting with cataract at start of XPOVIO therapy. Treatment of cataracts usually requires surgical removal of the cataract.

6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

8.1 Pregnancy

8.2 Lactation

8.3 Females and Males of Reproductive Potential

XPOVIO can cause fetal harm when administered to a pregnant woman [see Use in Specific Populations (8.1)].

8.4 Pediatric Use

The safety and effectiveness of XPOVIO have not been established in pediatric patients.

8.5 Geriatric Use

In BOSTON, of the 195 patients with multiple myeloma who received XPOVIO in combination with bortezomib and dexamethasone, 56% were 65 years of age and older, while 17% were 75 years of age and older. No overall differences in effectiveness were observed between these patients and younger patients. When comparing patients 65 years of age and older to younger patients, older patients had a higher incidence of discontinuation due to an adverse reaction (28% vs 13%) and a higher incidence of serious adverse reactions (56% vs 47%).

In STORM, of the 202 patients with multiple myeloma who received XPOVIO, 49% were 65 years of age and older, while 11% were 75 years of age and older. No overall difference in effectiveness was observed in patients over 65 years of age, including patients over 75 years of age, when compared with younger patients. When comparing patients 75 years of age and older to younger patients, older patients had a higher incidence of discontinuation due to an adverse reaction (44% vs 27%), higher incidence of serious adverse reactions (70% vs 58%), and higher incidence of fatal adverse reactions (17% vs 9%).

Among 134 patients with DLBCL who received XPOVIO in SADAL, 61% were 65 years of age and older, while 25% were 75 years of age and older. Clinical studies of XPOVIO in patients with relapsed or refractory DLBCL did not include sufficient numbers of patients aged 65 and over to determine whether they respond differently from younger patients.

12.1 Mechanism of Action

In nonclinical studies, selinexor reversibly inhibits nuclear export of tumor suppressor proteins (TSPs), growth regulators, and mRNAs of oncogenic proteins by blocking exportin 1 (XPO1). XPO1 inhibition by selinexor leads to accumulation of TSPs in the nucleus and reductions in several oncoproteins, such as c-myc and cyclin D1, cell cycle arrest, and apoptosis of cancer cells. Selinexor demonstrated pro-apoptotic activity in vitro in multiple myeloma cells and showed anti-tumor activity in murine xenograft models of multiple myeloma and diffuse large B cell lymphoma. The combination of selinexor and dexamethasone or bortezomib demonstrated synergistic cytotoxic effects in multiple myeloma in vitro and increased anti-tumor activity in murine xenograft multiple myeloma models in vivo, including those resistant to proteasome inhibitors.

12.2 Pharmacodynamics

An increase in selinexor exposure was associated with an increase in the probability of dose modification and some adverse reactions.

12.3 Pharmacokinetics

Selinexor Cmax and AUC increased proportionally over a dose range from 3 mg/m2 to 85 mg/m2 (0.05 to 1.44) times the maximum approved recommended dose, based on 1.7 m2 body surface area. No clinically relevant accumulation at steady state was observed. Selinexor Cmax and AUC0-INF after administration of a single dose of XPOVIO in patients with hematologic malignancies are presented in Table 10.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity studies have not been conducted with selinexor.

Selinexor was not mutagenic in vitro in a bacterial reverse mutation (Ames) assay and was not clastogenic in either the in vitro cytogenetic assay in human lymphocytes or in the in vivo rat micronucleus assay.

Fertility studies in animals have not been conducted with selinexor. In repeat-dose oral toxicity studies, selinexor was administered for up to 13 weeks in rats and monkeys. Reduced sperm, spermatids, and germ cells in epididymides and testes were observed in rats at ≥1 mg/kg, decreased ovarian follicles were observed in rats at ≥2 mg/kg, and single cell necrosis of testes was observed in monkeys at ≥1.5 mg/kg. These dose levels resulted in systemic exposures approximately 0.11, 0.28, and 0.53 times, respectively, the exposure (AUClast) in humans at the recommended human dose of 80 mg.

14.1 Relapsed or Refractory Multiple Myeloma

XPOVIO Combination with Bortezomib and Dexamethasone (XVd)

The efficacy of XPOVIO in combination with bortezomib and dexamethasone was evaluated in BOSTON (NCT03110562). BOSTON was a global, randomized, open label, active-controlled trial in adult patients who had received 1 to 3 prior anti-MM regimens. Prior treatment with bortezomib or other PI was allowed.

Patients with Grade 2 or higher peripheral neuropathy at study entry were excluded.

Patients were randomized to receive one of the following:

• XPOVIO 100 mg orally once weekly on Days 1, 8, 15, 22, 29 in combination with bortezomib 1.3 mg/m2 administered subcutaneously once weekly on Days 1, 8, 15, 22 and dexamethasone 20 mg taken orally twice weekly on Days 1, 2, 8, 9, 15, 16, 22, 23, 29, and 30 of each 35-day cycle [XVd arm] or
• Bortezomib 1.3 mg/m2 administered subcutaneously twice weekly on Days 1, 4, 8, 11 and dexamethasone 20 mg taken orally four times weekly on Days 1, 2, 4, 5, 8, 9, 11, 12 of each 21-day cycle for the first 8 cycles, followed by bortezomib 1.3 mg/m2 administered subcutaneously once weekly on Days 1, 8, 15, 22 and dexamethasone 20 mg taken orally twice weekly on Days 1, 2, 8, 9, 15, 16, 22, 23, 29, and 30 of each 35-day cycle (Cycle ≥9) [Vd arm].

Treatment continued in both arms until disease progression or unacceptable toxicity. Randomization was stratified based on prior proteasome inhibitor therapies exposure (yes versus no), number of prior regimens (1 versus >1), Stage (III versus I or II) according to the Revised-International Staging System (RISS) and region. Upon confirmed progressive disease (PD), patients in the Vd arm could receive XPOVIO in combination with bortezomib and dexamethasone (XVd) or XPOVIO 100 mg taken orally on Days 1, 8, 15, 22, 29 with dexamethasone 20 mg taken orally on Days 1, 2, 8, 9, 15, 16, 22, 23, 29, and 30 of each 35-day cycle.

A total of 402 patients were randomized: 195 to XVd arm and 207 to Vd arm. Baseline patient demographics and disease characteristics are summarized in Table 11 and Table 12, respectively.

Table 11: Baseline Demographics (BOSTON)

Characteristic	XVd (n=195)	Vd (n=207)
Median age, years (range)	66 (40, 87)	67 (38, 90)
Age distribution, n (%)      <65 years	86 (44)	75 (36)
65 – 74 years	75 (38)	85 (41)
≥75 years	34 (17)	47 (23)
Sex, n (%)      Male	115 (59)	115 (56)
Female	80 (41)	92 (44)
Race, n (%)      White	161 (83)	165 (80)
Black or African American	4 (2)	7 (3)
Asian	25 (13)	25 (12)
Other	0	1 (0.5)
Missing	5 (3)	9 (4)

Table 12: Disease Characteristics (BOSTON)

a. Includes any of del (17p)/p53, t (14;16), t (4;14), 1q21.
Parameter	XVd (n=195)	Vd (n=207)
Median years from diagnosis to randomization (range)	3.81 (0.4,23.0)	3.59 (0.4, 22.0)
ECOG performance status score, n (%)      0-1	175 (90)	191 (92)
≥2	20 (10)	16 (8)
Creatinine Clearance, n (%), mL per minute      <30	3 (1.5)	10 (5)
30 to 59	53 (27)	60 (29)
≥60	139 (71)	137 (66)
Revised International Staging System at Baseline, n (%)      I	56 (29)	52 (25)
II	117 (60)	125 (60)
III	12 (6)	16 (8)
Unknown	10 (5)	14 (7)
Number of Prior Therapies, n (%)      1      2      3	99 (51) 65 (33) 31 (16)	99 (48) 64 (31) 44 (21)
Type of known prior therapy, n (%) Stem      Cell transplantation	76 (39)	63 (30)
Lenalidomide	77 (39)	77 (37)
Pomalidomide	11 (6)	7 (3)
Bortezomib	134 (69)	145 (70)
Carfilzomib	20 (10)	21 (10)
Daratumumab	11 (6)	6 (3)
Median weeks since end of last prior therapy, (range)	48 (1, 1088)	42 (2, 405)
Known high-risk cytogeneticsa, n (%)	97 (50)	95 (46)

Efficacy was based on progression free survival (PFS) according to the International Myeloma Working Group (IMWG) Uniform Response Criteria for Multiple Myeloma, as assessed by an Independent Review Committee (IRC). Efficacy results based on a preplanned PFS interim analysis, are shown in Table 13 and Figure 1.

Table 13: Efficacy Results per IRC in Multiple Myeloma (BOSTON)

a. Hazard ratio is based on stratified Cox's proportional hazard regression modeling, p-value based on stratified log-rank test.
Median follow up of 15.1 months at the time of the analysis.
b. The pre-planned PFS interim analysis boundary of statistical significance was defined as a p-value <0.0103.
c. Includes sCR + CR + VGPR + PR, p value based on Cochran-Mantel-Haenszel test.
d. Includes sCR + CR + VGPR, p value based on Cochran-Mantel-Haenszel test.
	XVd (n=195)	Vd (n=207)
Progression Free Survival (PFS)a      Hazard Ratio [95% CI]	0.70 [0.53, 0.93]
One-sided p-valueb	0.0075
Median PFS in months [95% CI]	13.9 (11.7, Not Reached)	9.5 (7.6, 10.8)
Overall Response Rate (ORR)c, n (%)	149 (76.4)	129 (62.3)
95% CI	(69.8, 82.2)	(55.3, 68.9)
One-sided p-value	0.0012
Stringent Complete Response (sCR)	19 (10)	13 (6)
Complete Response (CR)	14 (7)	9 (4)
Very Good Partial Response (VGPR)	54 (28)	45 (22)
Partial Response (PR)	62 (32)	62 (30)
≥ VGPR Response Rated, n (%)	87 (44.6)	67 (32.4)
95% CI	(37.5, 51.9)	(26.0, 39.2)
One-sided p-value	0.0082

Figure 1: Kaplan-Meier Curve of PFS (BOSTON)

The median time to response was 1.4 months in the XVd arm and 1.6 months in the Vd arm. The median duration of response, among responding patients, was 20.3 months and 12.9 months in the XVd and Vd arms, respectively.

14.2 Relapsed or Refractory Diffuse Large B-Cell Lymphoma

The efficacy of XPOVIO monotherapy was evaluated in SADAL (KCP-330-009; NCT02227251). SADAL was a multicenter, single-arm, open-label study of adults with relapsed or refractory DLBCL, not otherwise specified (NOS), after 2 to 5 systemic regimens. Eligible patients were not candidates for autologous hematopoietic stem cell transplantation (HSCT). The study required a minimum of 60 days since last systemic therapy, with a minimum of 98 days in patients with refractory disease (defined as less than partial response) to last systemic therapy.

Patients received XPOVIO 60 mg orally on Days 1 and 3 of each week. Treatment continued until disease progression or unacceptable toxicity. Of 134 patients evaluated, the median age was 67 years (range: 35-91), 59% were male, 79% were White, and 7% were Asian. Most patients (88%) had an ECOG performance status of 0 or 1. The diagnosis was de novo DLBCL not otherwise specified (NOS) in 75% and transformed DLBCL in 23%. The median number of prior systemic therapies was 2 (range: 1-5), with 63% of patients receiving 2 prior systemic therapies, 24% receiving 3 prior therapies, and 10% receiving 4 or 5 prior therapies. Twenty-eight percent had documented refractory disease to the most recent therapy; 30% had prior autologous HSCT. The median time from last systemic therapy to the start of XPOVIO was 5.4 months overall and 3.6 months in the patients with refractory disease.

Efficacy was based on overall response rate (ORR) and duration of response as assessed by an Independent Review Committee (IRC) using Lugano 2014 criteria (Table 17). The median time to first response was 8.1 weeks (range: 6.7-16.4 weeks).

Dosing Instructions [see Dosage and Administration (2)]:

• Instruct patients to take XPOVIO exactly as prescribed.
• Advise patients to swallow the tablet whole with water. The tablet should not be broken, chewed, crushed, or divided.
• If a patient misses a dose, advise them to take their next dose at its regularly scheduled time. If a patient vomits or misses a dose of XPOVIO, advise them to take the next dose on the next regularly scheduled day.
• Advise patients that XPOVIO comes in a child-resistant blister pack.
• Advise patients to take their prescribed dexamethasone (if applicable) and prophylactic anti-nausea medications as directed [see Dosage and Administration (2.1, 2.3)].
• Advise patients that blood tests and body weight will be monitored at baseline and during treatment as clinically indicated, with more frequent monitoring during the first three months of treatment [see Dosage and Administration (2.3)].
• Advise patients to maintain appropriate fluid and caloric intake throughout their treatment [see Dosage and Administration (2.4)].

Hematologic Adverse Reactions

Thrombocytopenia

Advise patients that they may develop low platelet counts (thrombocytopenia). Symptoms of thrombocytopenia may include bleeding and easy bruising. Advise patients that platelet counts will be monitored at baseline, during treatment, and as clinically indicated, with more frequent monitoring during the first 3 months of treatment. Advise patients to report signs of bleeding right away [see Warnings and Precautions (5.1)].

Anemia

Advise patients that they may develop anemia. Symptoms of anemia may include fatigue and shortness of breath. Advise patients to report signs or symptoms of anemia [see Adverse Reactions (6.1)].

Neutropenia

Advise patients that they may develop low neutrophil counts which may increase their susceptibility to infection [see Warnings and Precautions (5.2)]. Advise patients that neutrophil counts will be monitored at baseline, during treatment, and as clinically indicated, with more frequent monitoring during the first 3 months of treatment.

Gastrointestinal Adverse Reactions

Advise patients they may experience nausea/vomiting or diarrhea and to contact their physician if these adverse reactions occur or persist [see Warnings and Precautions (5.3)].

Advise patients that they may experience weight loss or decreased appetite. Advise patients to report decreased appetite and weight loss [see Warnings and Precautions (5.3)].

Hyponatremia

Advise patients that they may develop low sodium levels (hyponatremia). Most cases of hyponatremia were not associated with specific symptoms. Advise patients that levels of sodium will be monitored at baseline and during treatment as clinically indicated, with more frequent monitoring during the first two months of treatment [see Warnings and Precautions (5.4)].

Serious Infection

Advise patients of the possibility of serious infections. Instruct patients to immediately report infection-related signs or symptoms (e.g., chills, fever) [see Warnings and Precautions (5.5)].

Neurotoxicity

Advise patients that they may experience confusion and dizziness. Advise patients to report symptoms of neurological toxicity right away. Advise patients not to drive or operate hazardous machinery until the neurological toxicity fully resolves. Advise patients to use fall prevention measures as warranted [see Warnings and Precautions (5.6)].

Embryo-Fetal Toxicity

Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to contact their healthcare provider of a known or suspected pregnancy [see Warnings and Precautions (5.7) and Use in Specific Populations (8.1)].

Advise females of reproductive potential and males with a female partner of reproductive potential to use effective contraception during treatment with XPOVIO and for 1 week after the final dose [see Use in Specific Populations (8.3)].

Cataract

Advise patients of the potential risk of worsening or new onset of cataract, that may require surgery. Advise patients to readily inform their healthcare professionals of changes in vision (i.e. blurred vision) and that ophthalmologic evaluation may be performed as clinically indicated [see Warnings and Precautions (5.8)].

Fatigue

Advise patients that they may experience fatigue [see Adverse Reactions (6.1)].

Lactation

Advise women not to breastfeed during treatment with XPOVIO and for 1 week after the last dose [see Use in Specific Populations (8.2)].

Concomitant Medications

Advise patients to take 5-HT3 antagonist prophylactic treatment and other anti-nausea agents prior to and during treatment with XPOVIO [see Dosage and Administration (2.4)].

Advise patients to speak with their physician about other medications they are currently taking and before starting any new medication.

Manufactured for and marketed by: Karyopharm Therapeutics Inc., 85 Wells Avenue, Newton, MA, 02459.
XPOVIO is a registered trademark of Karyopharm Therapeutics Inc.
©2025 Karyopharm Therapeutics Inc.
For more information, call 1-888-209-9326 or go to www.XPOVIO.com.