(KPTI) Data Presentations at American Society of Hematology Annual Meeting

Published Abstracts Include Clinical Data on Selinexor (KPT-330) as Single-Agent in Non-Hodgkin’s Lymphoma and in Combination With Dexamethasone in Multiple Myeloma

NEWTON, Mass., Nov. 6, 2014  — Karyopharm Therapeutics Inc. (Nasdaq:KPTI), a clinical-stage pharmaceutical company, today announced that clinical and pre-clinical data for its lead drug candidate, Selinexor (KPT-330), a first-in-class, oral Selective Inhibitor of Nuclear Export / SINE™ compound, will be presented at the 56th American Society of Hematology (ASH) Annual Meeting, which is being held from December 6-9, 2014 in San Francisco.

“We are excited that our growing body of data in hematologic malignancies for our lead drug candidate, Selinexor, will be presented at ASH, including promising clinical data of Selinexor in patients with heavily pretreated, relapsed and refractory aggressive non-Hodgkin’s lymphoma and additional preclinical and clinical data demonstrating synergistic activity of Selinexor when combined with dexamethasone in multiple myeloma,” said Sharon Shacham, PhD, MBA, President and Chief Scientific Officer of Karyopharm. “We are committed to uncovering the potential of our SINE™ compounds, in particular the broad anti-cancer activity in hematologic and solid tumor malignancies demonstrated by our first-in-class agent, oral Selinexor.”

Oral Presentation (Selinexor):

Title:	The Oral Selective Inhibitor of Nuclear Export (SINE) Selinexor (KPT-330) Demonstrates Broad and Durable Clinical Activity in Relapsed / Refractory Non-Hodgkin’s Lymphoma (NHL)
Author:	Kuruvilla
Publication #:	396
Session:	623. Lymphoma: Chemotherapy, excluding Pre-Clinical Models: Adjusting Induction Therapy in Large Cell Lymphoma
Date/Time:	Monday, December 8, 2014 11:45 AM PT
Location:	Moscone Center, South Building, Esplanade 304-306-308
Highlights of topline abstract data: Overall response rate (partial response or better) of 40% and disease control rate (stable disease or better) of 80% in 10 patients with relapsed and refractory aggressive non-Hodgkin’s lymphoma treated with single-agent Selinexor dosed twice weekly at ≥60mg/m2 (equivalent to approximately 100mg doses). A 33% response rate was observed in 27 patients dosed at 35-50mg/m2 (equivalent to approximately 60-85mg doses), along with a 25% response rate at lower doses. These data are current through August 5, 2014, and will be updated in detail at ASH.

Poster Presentations (Selinexor):

TITLE:	Selinexor Demonstrates Marked Synergy with Dexamethasone (Sel-Dex) in Preclinical Models and in Patients with Heavily Pretreated Refractory Multiple Myeloma (MM)
Author:	Chen
Publication #:	4773
Session:	653. Myeloma: Therapy, excluding Transplantation: Poster III
Date/Time:	Monday, December 8, 2014, 6:00 PM – 8:00 PM PT
Location:	Moscone Center, West Building, Level 1
Highlights of topline abstract data: Overall response rate (partial response or better) of 60% and clinical benefit rate (minimal response or better) of 80% in 10 patients with heavily pretreated and refractory multiple myeloma treated with Selinexor in combination with low-dose dexamethasone, each dosed twice weekly at 45mg/m2 and 20mg, respectively. These data are current through August 5, 2014, and will be updated in detail at ASH.
TITLE:	Anti-Myeloma Activity of Combined Inhibition of the Proteasome with Carfilzomib (CFZ) and XPO1/CRM1-Dependent Nuclear Export by Selinexor (KPT-330) Via a Novel Mechanism of Intracellular Activation of Caspase 10-Dependent Apoptosis
Author:	Rosebeck
Publication #:	3443
Session:	652. Myeloma: Pathophysiology and Pre-Clinical Studies, excluding Therapy: Poster II
Date/Time:	Sunday, December 7, 2014, 6:00 PM – 8:00 PM PT
Location:	Moscone Center, West Building, Level 1
TITLE:	Selinexor-Induced Thrombocytopenia Results from the Inhibition of Megakaryocyte Progenitor Cells in the Early Stage of Megakaryopoiesis
Author:	Machlus
Publication #:	1458
Session:	311. Disorders of Platelet Number or Function: Poster I
Date/Time:	Saturday, December 6, 2014, 5:30 PM – 7:30 PM PT
Location:	Moscone Center, West Building, Level 1
TITLE:	Gene Expression and Transcription Factor (TF) Activation Profiling Identifies Suppression of Multiple Myeloma (MM) Cell Survival and Chemoresistance Pathways by Inhibition of XPO1/CRM1-Dependent Nuclear Export with Selinexor
Author:	Rosebeck
Publication #:	3444
Session:	652. Myeloma: Pathophysiology and Pre-Clinical Studies, excluding Therapy: Poster II
Date/Time:	Sunday, December 7, 2014, 6:00 PM – 8:00 PM PT
Location:	Moscone Center, West Building, Level 1

Additional posters detailing preclinical data from Karyopharm’s PAK4 inhibitor program, as well as preclinical data of Selinexor in acute myeloid leukemia (AML), will also be presented.

About Selinexor

Selinexor (KPT-330) is a first-in-class, oral Selective Inhibitor of Nuclear Export / SINE™ compound. Selinexor functions by inhibiting the nuclear export protein XPO1 (also called CRM1), leading to the accumulation of tumor suppressor proteins in the cell nucleus, which subsequently reinitiates and amplifies their tumor suppressor function. This is believed to lead to the selective induction of apoptosis in cancer cells, while largely sparing normal cells. Over 450 patients have been treated with Selinexor in Phase 1 and Phase 2 clinical trials in advanced hematologic malignancies and solid tumors. Karyopharm has initiated a registration-directed clinical trial of Selinexor in older patients with acute myeloid leukemia and two additional registration-directed clinical trials in hematological indications are expected to begin enrollment during 2014. Additional Phase 1 and Phase 2 studies are ongoing or currently planned, including multiple investigator-sponsored studies of Selinexor in combination with one or more approved therapies. The latest clinical trial information for Selinexor is available at www.clinicaltrials.gov.

About Karyopharm Therapeutics

Karyopharm Therapeutics Inc. (Nasdaq:KPTI) is a clinical-stage pharmaceutical company focused on the discovery and development of novel drugs directed against nuclear transport targets for the treatment of cancer and other major diseases. Karyopharm’s SINE™ compounds function by binding with and inhibiting the nuclear export protein XPO1 (or CRM1). SINE™ compounds have also shown biological activity in models of autoimmune disease, certain viruses, and wound-healing. Karyopharm was founded by Dr. Sharon Shacham and is located in Newton, Massachusetts. For more information, please visit www.karyopharm.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning 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 for Karyopharm’s drug candidates, including the timing of initiation of certain trials and of the reporting of data from such trials. Such statements are subject to numerous important factors, risks and uncertainties that may cause actual events or results to differ materially from the company’s current expectations. For example, there can be no guarantee that any of Karyopharm’s SINE™ compounds, including Selinexor (KPT-330) or any PAK4 inhibitor, or any other drug candidate that 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. Management’s expectations and, therefore, any forward-looking statements in this press release could also be affected by risks and uncertainties relating to a number of other factors, 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 U.S. Food and Drug Administration and other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies; Karyopharm’s ability to obtain and maintain requisite regulatory approvals and to enroll patients in its clinical trials; unplanned cash requirements and expenditures; development of drug candidates by Karyopharm’s competitors for diseases in 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 are described under the caption “Risk Factors” in Karyopharm’s Annual Report on Form 10-K for the year ended December 31, 2013, which is on file with the Securities and Exchange Commission (SEC), and in other filings that Karyopharm may make with the SEC in the future. Any forward-looking statements contained in this press release speak only as of the date hereof, and Karyopharm expressly disclaims any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise.

CONTACT: Investor / Company Contact:

         Justin Renz
         (617) 658-0574
         jrenz@karyopharm.com

         Media Contact:

         Ryan Flinn
         415.946.1059
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