th Annual J.P. Morgan Healthcare Conference January 8-11, 2018 Forward-looking Statements This presentation contains forward-looking statements within the meaning of the safe harbor provisions of The Private Securities L

Targeting Disease at the Nuclear Pore Exhibit 99.1

6th Annual J.P. Morgan Healthcare Conference January 8-11, 2018

Forward-looking Statements This presentation contains forward-looking statements within the meaning of the

safe harbor provisions of The Private Securities Litigation Reform Act of 1995. Such forward-looking statements include those regarding the therapeutic potential of and potential clinical development plans and commercialization for

Karyopharm s drug candidates, including the timing of initiation of certain trials and of the reporting of data from such trials, and Karyopharm s strategic and financial plans and expectations as well as financial projections for

Karyopharm. Such statements are subject to numerous important factors, risks and uncertainties that may cause actual events or results to differ materially from Karyopharm s current expectations. For example, there can be no guarantee that any

of Karyopharm s SINE compounds, including selinexor (KPT-330) and eltanexor (KPT-8602), Karyopharm s second generation SINE compound, or KPT-9274, Karyopharm s first-in-class oral dual inhibitor of PAK4 and NAMPT, or any other drug candidate Karyopharm is developing,

will successfully complete necessary preclinical and clinical development phases or that development of any of Karyopharm s drug candidates will continue. Further, there can be no guarantee that any positive developments in Karyopharm s

drug candidate portfolio will result in stock price appreciation. In addition, even if Karyopharm receives marketing approval for selinexor or another drug candidate, there can be no assurance that Karyopharm will be able to successfully

commercialize that drug candidate. Management s expectations and, therefore, any forward-looking statements in this presentation could also be affected by risks and uncertainties relating to a number of other factors, many of which are beyond

Karyopharm s control, including the following: Karyopharm s results of clinical trials and preclinical studies, including subsequent analysis of existing data and new data received from ongoing and future studies; the content and timing of

decisions made by the FDA and other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies, including with respect to the need for additional clinical studies; Karyopharm s ability to obtain

and maintain requisite regulatory approvals and to enroll patients in its clinical trials; Karyopharm s partnership with Ono and the potential future financial implications of such partnership; unplanned cash requirements and expenditures;

development of drug candidates by Karyopharm s competitors for diseases for which Karyopharm is currently developing its drug candidates; and Karyopharm s ability to obtain, maintain and enforce patent and other intellectual property

protection for any drug candidates it is developing. These and other risks, including those which may impact management s expectations, are described in greater detail under the heading Risk Factors in Karyopharm s Quarterly

Report on Form 10-Q for the quarter ended September 30, 2017, which is on file with the SEC, and in subsequent filings filed by Karyopharm with the SEC. Any forward-looking statements contained in this

presentation are for informational purposes only and speak only as of the date hereof. Other than as is required by law, Karyopharm expressly disclaims any obligation to update any forward-looking statements, whether as a result of new information,

future events or otherwise. Karyopharm s website is http://www.karyopharm.com. Karyopharm regularly uses its website to post information regarding its business, drug development programs and governance. Karyopharm encourages investors to use

www.karyopharm.com, particularly the information in the section entitled Investors, as a source of information about Karyopharm. References to www.karyopharm.com in this presentation are not intended to, nor shall they be deemed to,

incorporate information on www.karyopharm.com into this presentation by reference. Unless otherwise noted, this presentation contains data that are interim and unaudited based on site reports. In addition, data included in this presentation have not

been updated and are as of the cutoff date for the applicable medical conference presentation. Unless otherwise noted, all reference to market sizes are based on reports from Global Data or Karyopharm internal estimates. 2018 Karyopharm

Karyopharm Highlights Strong leadership team and balance sheet First-in-class, oral SINE compounds Lead asset with blockbuster potential 1 Global Data, 2 Assuming a positive outcome from Phase 2b STORM study, 3 Assuming positive outcome from Phase 2b SADAL study, 4

Assuming positive outcome from Phase 3 BOSTON study, 5 Assuming positive outcome from Phase 3 portion of SEAL study Hematologic Malignancies Multiple Myeloma Diffuse Large B-cell Lymphoma Liposarcoma

Gynecologic Cancers Solid Tumor Malignancies 2018 Karyopharm Therapeutics Inc. Multiple near term catalysts from broad, late-stage pipeline Executive team with past successes in lead indications; cash expected to fund the company into 2019

Unique, broadly applicable mechanism of action with single agent activity and works well in combinations; patent life through 2032+ Selinexor is combinable with existing backbone therapies and has the potential to be the next

backbone therapy in myeloma, a market projected to be $22B in 20231 Data readouts (next 24 months): STORM (April 2018), SADAL (2H18), BOSTON (2019), SEAL (2019) Submissions requesting approval: Accelerated approval in multiple

myeloma (2018)2, accelerated approval in DLBCL (2019)3, full approval in multiple myeloma (2020)4, full approval in liposarcoma (2020)5 Anticipated launch for selinexor in multiple myeloma and DLBCL in 2019, followed by other indications in 2020+

Preparing for product launches and revenues

Karyopharm s All Oral Pipeline COMMERCIAL RIGHTS Japan* Relapsed/refractory | BOSTON Relapsed/refractory |

STOMP Penta-refractory | STORM 1 Oral selinexor, Velcade (bortezomib) and dexamethasone vs. Velcade and dexamethasone 2 Oral selinexor + dexamethasone 3 Oral selinexor and dexamethasone + Revlimid (lenalidomide), Pomalyst

(pomalidomide), Velcade, Kyprolis (carfilzomib) or Darzalex (daratumumab) 2018 Karyopharm Therapeutics Inc. AREA OF THERAPY PRECLINICAL PHASE I PHASE II PHASE III HEMATOLOGIC MALIGNANCIES Multiple Myeloma SELINEXOR + VELCADE1

SELINEXOR2 SELINEXOR + BACKBONE THERAPIES3 Diffuse Large B-cell Lymphoma | SADAL SELINEXOR SOLID TUMOR MALIGNANCIES Liposarcoma | SEAL SELINEXOR Gynecologic Malignancies | SIGN SELINEXOR Glioblastoma | KING

SELINEXOR ADDITIONAL ONCOLOGY PROGRAMS MDS, CRC, PrC Eltanexor (KPT-8602) Solid Tumors & Lymphoma KPT-9274 OTHER INDICATIONS Influenza, Other Viruses, Canine

Lymphoma VERDINEXOR (KPT-335) ALS, MS, DMD, TBI & Other Indications KPT-350 Relapsed/refractory | BOSTON Relapsed/refractory | STOMP Penta-refractory | STORM

*Territories: Japan, S. Korea, Taiwan, Hong Kong, and ASEAN countries **Anivive holds exclusive worldwide rights to research, develop and commercialize verdinexor only for the treatment of cancer in companion animals **

Selinexor/SINE Mechanism of Action: Inhibition of XPO1 2018 Karyopharm Therapeutics Inc.

Selinexor: A Growing Body of Safety Data 2,200 Total patients treated to date Favorable emerging tolerability

profile; multiple ongoing Phase 3 studies Dosing regimens utilized in key Phase 2 and 3 trials (e.g., BOSTON, STORM, STOMP, SADAL and SEAL) have shown predictable and manageable tolerability, particularly when used once weekly in combination

regimens Common side effects are predictable across multiple tumor types and generally reversible and/or manageable with standard supportive care Combination regimens well tolerated with observed additive or synergistic activity and potential to re-sensitize to prior therapies Phase 3 BOSTON selinexor regimen allows for use of 40% less Velcade and 25% less dexamethasone than standard Velcade and dexamethasone dosing In certain trials, side effects

reported from treatment arms evaluating selinexor and dexamethasone in combination with other anti-myeloma agents are similar to, or reduced, compared to selinexor and dexamethasone alone ~46 Number of clinical trials ongoing and/or completed

2018 Karyopharm Therapeutics Inc. 1 Per ClinicalTrials.gov (as of Dec 31, 2017); 5 of 46 are company-sponsored and currently enrolling >10 Number of cancers explored 1

Selinexor in Hematologic Malignancies Multiple Myeloma

of patients survive 5 years3 50% Americans are currently living with MM3 120,000 Approximately people worldwide

are diagnosed annually2 86,000 An estimated 30,000 people in the US are diagnosed annually1 An estimated 1 American Cancer Society 2 Becker, N. Recent Results Cancer Res. 2011;183:25-35. doi: 10.1007/978-3-540-85772-3_2 3 National Cancer Institute Multiple Myeloma Multiple myeloma is a cancer of plasma cells. Normal

plasma cells are found in the bone marrow and make antibodies that help the body attack and kill germs1 Myeloma is characterized by low blood counts (e.g., anemia), bone and calcium problems, infections, kidney problems and light chain amyloidosis1

Myeloma is treatable, but >12,000 deaths still occur each year in the U.S.1 2018 Karyopharm Therapeutics Inc.

U.S. Multiple Myeloma Treatment Landscape in 2018 FOLLOW ON 2nd LINE FOLLOW ON 3rd/4th LINE FRONTLINE

V=Velcade (bortezomib), R=Revlimid (lenalidomide), d=dexamethasone, K=Kyprolis (carfilzomib), D=Darzalex (daratumumab), SCT=Stem cell transplantation, R/R=Relapsed/refractory, P=Pomalyst (pomalidomide), DOR=Duration of

response, F=Farydak (panobinostat), M=melphalan, N=Ninlaro (ixazomib), C=cyclophosphamide, E=Empliciti (elotuzumab) Clinical study / Other Triplets or Quadruplets No Standard of Care Despite multiple treatments available, nearly all

patients will develop refractory disease Highly dynamic combination treatment landscape Focus on novel mechanisms and combinability / synergy Oral administration is an advantage ~35% Transplant Eligible Induction VRd, KRd, DRd, Others Autologous SCT

Intermediate or High Risk: Vd or Kd Maintenance Low Risk: Rd Maintenance KRd, DRd, DVd, ERd Clinical Trial Autologous SCT if prior SCT had PFS of >18 months ~65% Transplant Ineligible VRd, Vd or Rd KRd (high risk) VMP (DVMP) (EU mainly), (DRd)

Continuous Treatment until progression (may move to doublet) DVd, DRd, KRd, NRd, V or N + Cd, ERd, High Kd 2018 Karyopharm Therapeutics Inc. KPd, VPd, DPd Antibody and triplets, FVd

Worldwide MM market estimated ~$11 billion in 2015, increasing to $22 billion by 20234 Individual MM

drugs with single-agent1 activity may generate peak sales $1-2B+ Oral selinexor could combine with any of the agents currently in use to potentially improve ORR and PFS VELCADE 1 $>7B2 REVLIMID 1

$>2B2 POMALYST 1 $~2.5B3 DARZALEX 1 $>1B2 KYPROLIS 1 $>2B2 Multiple Myeloma: Potential Market Opportunity SELINEXOR 1 In combination with glucocorticoids. 2 Projected peak worldwide sales. 3 Peak worldwide sales. 4 Global data.

2018 Karyopharm Therapeutics Inc.

Planned Selinexor Development Strategy in Multiple Myeloma 2018 Karyopharm Therapeutics Inc. Phase 2b

STORM study1 addressing patients with penta-refractory myeloma Patients who have failed PIs, IMiDs and Darzalex Highest unmet need patients 1 Evaluating selinexor with low-dose dexamethasone Pivotal Phase

3 BOSTON study addressing patients with relapsed or refractory disease following 1-3 prior lines of therapy Selinexor combined with once-weekly Velcade Phase 1b/2 STOMP study in combination with

backbone therapies Selinexor and low-dose dexamethasone combined with Revlimid , Pomalyst , Velcade , Kyprolis or Darzalex Future Phase 2/3 studies in combination for labeling

Ongoing single-arm clinical trial evaluating selinexor in combination

with low-dose dexamethasone in patients2 with penta-refractory3 myeloma STORM1: A Phase 2b Study In Myeloma 1 Selinexor Treatment of Refractory Myeloma 2 Median 7 prior regimens 3 Patients who have

previously received two PIs, Velcade (bortezomib) and Kyprolis (carfilzomib), and two IMiDs, Revlimid (lenalidomide) and Pomalyst (pomalidomide), and their disease is refractory to at least one PI, at least one IMiD, and their

disease is also refractory to an anti-CD38 monoclonal antibody, such as Darzalex (daratumumab) or isatuximab, and has progressed following their most recent therapy 2018 Karyopharm Therapeutics Inc.

Top-line data expected April 2018

STORM: A Phase 2b Study1 In Myeloma Safety: Most common non-hematologic

AEs were nausea, anorexia and fatigue; primarily Grade 1/2 and manageable with standard supportive care and/or dose modification Most common hematologic AEs were Grade 3 cytopenias; generally not

associated with clinical sequellae Low rates of Grade 3 non-hematologic toxicities; no new safety signals Other AEs of interest: Grade 4 infection (1.3%; n=1),

Grade 2 neuropathy (1.3%; n=1), sepsis (1.3%; n=1) Next steps: Top-line data in penta-refractory myeloma expected in April 2018 If positive data, potential NDA submission second half of 2018 requesting

accelerated approval, with potential EMA filing to follow 21% OVERALL RESPONSE RATE2,3 DURATION OF RESPONSE2,3 OVERALL SURVIVAL2,3 >11 All (n=78): Quad (n=48): 21% Penta (n=30): 20% Non-Responders ( SD/PD): Responders ( MR): 5 5.7 MONTHS MONTHS We believe selinexor is the most advanced agent being investigated in penta-refractory myeloma MONTHS 1 Vogl, DT, et

al. ASH 2016. Abstract 491. 2 Includes Very Good Partial Responses (VGPRs) and Partial Responses (PRs) 3 As adjudicated by an Independent Review Committee. 2018 Karyopharm Therapeutics Inc.

Ongoing randomized, open-label clinical trial evaluating once weekly selinexor, Velcade (bortezomib) and low-dose dexamethasone (dex) versus standard Velcade and low-dose dex in patients with relapsed or refractory MM, who have had 1-3

prior lines of therapy BOSTON1: A Phase 3 Study In Myeloma 1 Bortezomib, Selinexor and dexamethasone 2 Pts must have achieved PR, and completed proteasome inhibitor therapy at least 60 days prior

2018 Karyopharm Therapeutics Inc. Top-line data expected in 2019

STOMP1: A Phase 1b/2 Study in Myeloma Ongoing multi-arm clinical trial

evaluating selinexor and low-dose dex in combination with several currently marketed backbone therapies3 in patients with heavily pretreated, relapsed or refractory MM 1 Selinexor and Backbone

Treatments of Multiple Myeloma Patients, 2 Recommended Phase 2 dose (RP2D) established, 3 Revlimid , Pomalyst , Velcade , Kyprolis or Darzalex 2018 Karyopharm Therapeutics Inc. SRd SEL:60mg QW REV:25mg QD DEX:40mg QW SPd

SEL:60 or 80mg QW POM: 2-4mg QD DEX: 40mg QW SVd SEL:100mg QW VEL:1.3mg/m2 SC QW DEX:40mg QW or 20mg BIW SKd SEL:80 or 100mg QW KYP:56 or 70 mg/m2 IV QW DEX:40 mg QW SDd SEL:100mg QW DARZ:16mg/kg IV QW

DEX:40mg QW ORR & Safety Next expected data readout in 2018 N ^250 2 2 2

Next steps: Efficacy and safety observed in SVd arm informing ongoing Phase 3 BOSTON study Plan to report

updated data from ongoing arms in mid and late 2018 Safety: SRd (n=19): Most common Grade 1/2 AEs were nausea, anorexia, fatigue, weight loss, constipation and vomiting; most common Grade 3 adverse

events were thrombocytopenia and neutropenia SPd (n=31): Most common Grade 1/2 AEs were nausea, anorexia, fatigue and diarrhea; most common Grade 3 AEs were neutropenia, thrombocytopenia and anemia SVd

(n=42): All Grade AEs were consistent with those reported previously from SVd arm; Low rate of peripheral neuropathy (14%; n=6, all Grade 1/2) SDd (n=9): Most common Grade 1/2 AEs were fatigue, nausea and neutropenia; most common Grade 3/4 AEs were

thrombocytopenia, leukopenia, anemia and neutropenia STOMP: A Phase 1b/2 Study In Myeloma Selinexor + Velcade + dex (SVd)3 (n=40) Selinexor + Pomalyst + dex (SPd)2 (n=27) 1 White D, et al. ASH 2017. Abstract 1861. 2 Chen C, et al. ASH

2016. Abstract 3330. 3 Bahlis NJ, et al. ASH 2016. Abstract 977. 4 Patient population eligible for Phase 3 BOSTON study. 5 Gasparetto C, et al. ASH 2017. Abstract 3100. Selinexor + Revlimid + dex (SRd)1 (n=16) Selinexor + Darzalex + dex

(SDd)5 (n=8) 2018 Karyopharm Therapeutics Inc. 83% ORR (Non-Refractory to PIs) ORR 63% (All) 63% ORR (Pomalyst-Na ve and Revlimid-Relapsed or -Refractory ) ORR 56% (All) 92% ORR

(Revlimid-Na ve) 83% ORR (Darzalex-Na ve) ORR 63% (All) 4 ORR 81% (All)

FOLLOW ON 2nd LINE FOLLOW ON 3rd/4th LINE FRONTLINE V=Velcade (bortezomib), R=Revlimid

(lenalidomide), d=dexamethasone, K=Kyprolis (carfilzomib), D=Darzalex (daratumumab), SCT=Stem cell transplantation, R/R=Relapsed/refractory, P=Pomalyst (pomalidomide), DOR=Duration of response, F=Farydak (panobinostat),

M=melphalan, N=Ninlaro (ixazomib), C=cyclophosphamide, E=Empliciti (elotuzumab). * Global Data Clinical study / Other Triplets or Quadruplets No Standard of Care ~35% Transplant Eligible Induction VRd, KRd, DRd, Others Autologous SCT

Intermediate or High Risk: Vd or Kd Maintenance Low Risk: Rd Maintenance KRd, DRd, DVd, ERd Clinical Trial Autologous SCT if prior SCT had PFS of >18 months ~65% Transplant Ineligible VRd, Vd or Rd KRd (high risk) VMP (DVMP) (EU mainly), (DRd)

Continuous Treatment until progression (may move to doublet) DVd, DRd, KRd, NRd, V or N + Cd, ERd, High Kd 2018 Karyopharm Therapeutics Inc. KPd, VPd, DPd Antibody and triplets, FVd Phase 3 BOSTON Study ~$2B+ peak market opportunity* Phase 2b

STORM Study ~$500M peak market opportunity* Integration of Selinexor into the MM Landscape in 2019 and Beyond

Integration of Selinexor into the MM Landscape in 2019 and Beyond R=Revlimid (lenalidomide),

K=Kyprolis (carfilzomib), V=Velcade (bortezomib), P=Pomalyst (pomalidomide), D=Darzalex (daratumumab), d=dexamethasone, SCT=Stem cell transplantation, R/R=Relapsed/refractory, DOR=Duration of response, F=Farydak

(panobinostat), M=melphalan, N=Ninlaro (ixazomib), C=cyclophosphamide, E=Empliciti (elotuzumab), *With low-dose dexamethasone Phase 1b/2 STOMP study is generating selinexor data in combination with

backbone myeloma therapies 2018 Karyopharm Therapeutics Inc. FOLLOW ON 2nd LINE FOLLOW ON 3rd/4th LINE FRONTLINE Clinical study / Other Triplets or Quadruplets No Standard of Care ~35% Transplant Eligible Induction VRd, KRd, DRd,

Others Autologous SCT Intermediate or High Risk: Vd or Kd Maintenance Low Risk: Rd Maintenance KRd, DRd, DVd, ERd Clinical Trial Autologous SCT if prior SCT had PFS of >18 months ~65% Transplant Ineligible VRd, Vd or Rd KRd (high risk) VMP (DVMP)

(EU mainly), (DRd) Continuous Treatment until progression (may move to doublet) DVd, DRd, KRd, NRd, V or N + Cd, ERd, High Kd KPd, VPd, DPd Antibody and triplets, FVd The STOMP Study Evaluating selinexor* in combination with: Immunomodulatory agents

Proteasome inhibitors Anti-CD38 monoclonal antibodies isatuxumab (cyclophosphamide) Alkylating agents Investigators also evaluating other selinexor combina-tions, including Ninlaro , isatuximab and Cytoxan Selinexor has the potential