|Phase 2b STORM Efficacy as of September 6, 2016|
|Category||N 1||ORR (%)||CBR (%)||VGPR (%)||PR (%)||MR (%)||SD (%)||PD (%)||NE (%)|
|Overall||78||16 (21%)||25 (32%)||4 (5%)||12 (15%)||9 (12%)||27 (35%)||9 (12%)||17 (22%)|
|Quad 2||48||10 (21%)||14 (29%)||2 (4%)||8 (17%)||4 (8%)||21 (44%)||4 (8%)||9 (19%)|
|Penta 3||30||6 (20%)||11 (37%)||2 (7%)||4 (13%)||5 (17%)||6 (20%)||5 (17%)||8 (27%)|
|1One patient not included, did not have active myeloma||ORR=Objective Response Rate (VGPR+PR)|
|2The majority of these patients (40 of 48) received 6 doses per cycle||CBR=Clinical Benefit Rate (VGPR+PR+MR)|
|3The majority of these patients (19 of 30) received 8 doses per cycle||VGPR=Very Good Partial Response|
- Diverse Data Continue to Reinforce the Efficacy and Safety of Selinexor in Patients with Heavily Pretreated Refractory Multiple Myeloma - - Twenty-one Abstracts Selected, Including Nine Oral Presentations - NEWTON, Mass., Nov. 03, 2016 (GLOBE NEWSWIRE) -- Karyopharm Therapeutics Inc. (Nasdaq:KPTI), a clinical-stage pharmaceutical company, today announced that 21 abstracts have been selected for presentation, including 9 oral presentations, at the American Society of Hematology (ASH) 2016 annual meeting being held December 3-6, 2016 in San Diego. Two key abstracts being presented at the meeting will feature updated data from Karyopharm's Phase 2b STORM and Phase 1b/2 STOMP studies, which are evaluating selinexor (KPT-330), the Company's lead, novel, oral Selective Inhibitor of Nuclear Export (SINE™) compound, for the treatment of patients with multiple myeloma (MM). Selinexor has demonstrated robust and durable responses with favorable safety profiles in both studies and these data will be updated for presentation at the meeting. "The STORM and STOMP studies continue to demonstrate robust response rates, with selinexor showing tolerability, both as a single-agent and in combination with other widely used therapies in heavily pretreated patients with MM," said Sharon Shacham, PhD, MBA, President and Chief Scientific Officer of Karyopharm. "Collectively, the MM data being presented at ASH this year continue to support the efficacy and safety of oral selinexor, as well as our planned development path in MM, and we look forward to presenting even more mature data at the meeting in December." Updated Phase 2b STORM Clinical Data In an oral presentation titled, "Selinexor and Low Dose Dexamethasone in Patients with Lenalidomide, Pomalidomide, Bortezomib, Carfilzomib and Anti-CD38 Ab Refractory MM STORM Study," Dan T. Vogl, MD, MSCE, Assistant Professor of Medicine, Perelman School of Medicine, University of Pennsylvania, will present updated clinical data from the ongoing Phase 2b STORM study, a single-arm clinical trial evaluating selinexor in combination with low-dose dexamethasone in heavily pretreated patients with quad-refractory or penta-refractory disease. Patients with quad-refractory disease have documented evidence that they have previously received two PIs (bortezomib (Velcade®) and carfilzomib (Kyprolis®)) and two IMiDs (lenalidomide (Revlimid®) and pomalidomide (Pomalyst®)), and their disease is refractory to at least one PI, at least one IMiD, and has progressed following their most recent therapy. Patients with penta-refractory myeloma have quad-refractory disease that is also refractory to an anti-CD38 monoclonal antibody, such as daratumumab (Darzalex™) or isatuximab.
All responses were adjudicated by an Independent Review Committee (IRC). Among the 78 evaluable patients (median seven prior treatment regimens) at September 6, 2016, the overall response rate (ORR) was 21%, and included very good partial responses (VGPR) and partial responses (PR). Among the 48 patients in the quad-refractory group, the ORR was 21%. For comparison, in a similar quad-refractory patient population, Darzalex had an ORR of 21% and isatuximab had an ORR of 20%. Among the 30 patients in the penta-refractory group, the ORR was 20%. Clinical benefit rate (ORR + MR) was 32% (all patients), 29% (quad-refractory), and 37% (penta-refractory). Median overall survival (OS) was 9.3 months for all patients, greater than 11 months (median not reached) for responders (=PR), and 5.7 months for non-responders. Median duration of response (DOR) was approximately 5 months. The progression free survival (PFS) in this heavily pretreated population was 2.1 months. Grade =3 cytopenias were the most common side effects and were generally not associated with clinical sequellae. There were low rates of Grade =3 non-hematologic toxicities, with no new safety signals identified. In particular, there was one reported case of Grade =4 infection (1.3%) and there was one reported case of sepsis (1.3%).