13D Filing: Delphi Ventures VIII LP and Karyopharm Therapeutics Inc. (KPTI)

CUSIP NO.   48576U106

13D

Page 1 of 12

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Schedule 13D

INFORMATION TO BE INCLUDED IN STATEMENTS FILED
PURSUANT TO RULES 13d-1 (a) AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2 (a)

(Amendment No. 2)

Karyopharm Therapeutics Inc.

(Name of Issuer)

Common Stock,
par value $0.0001 per share

(Title of Class of Securities)

48576U106

(CUSIP Number)

Matthew Potter

c/o Delphi Ventures

160 Bovet Rd, Suite 408

San Mateo, CA 94402

(650) 854-9650

 

COPY TO:

Christine Wichrowski, Esq.

c/o Gunderson Dettmer Stough Villeneuve Franklin
& Hachigian, LLP

1200 Seaport Boulevard, Redwood City, California
94063

(650) 321-2400

(Name, Address
and Telephone Number of Person Authorized to Receive Notices and Communications)

April 28, 2017

 (Date
of Event Which Requires Filing of this Statement)

If the filing person has
previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing
this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box ¨.

Note: Schedules filed in
paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other
parties to whom copies are to be sent.

* The remainder of this
cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of
securities and for any subsequent amendment containing information which would alter disclosures provided in the cover page.

The information required
on the remainder of this cover page shall not be deemed to be “filed” for the purposes of Section 18 of the Securities
Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject
to all other provisions of the Act (however, see the Notes).

 

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