Inotek Pharmaceuticals Corp (ITEK): Billionaire Ken Griffin’ Citadel Investment Group Raises Stake to 6.5%

1.

NAME OF REPORTING PERSON

S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

Citadel Advisors LLC

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ¨

(b)¨

3.

SEC USE ONLY

4.

CITIZENSHIP OR PLACE OF ORGANIZATION

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH

5.

SOLE VOTING POWER

0

6.

SHARED VOTING POWER

1,871,258 shares

7.

SOLE DISPOSITIVE POWER

0

8.

SHARED DISPOSITIVE POWER

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

See Row 6 above

10.

CHECK BOX IF THE AGGREGATE AMOUNT
IN ROW (9) EXCLUDES

CERTAIN SHARES ¨

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

6.5%¹

12.

TYPE OF REPORTING PERSON

IA; OO; HC

The
percentages reported in this Schedule 13G are based upon 28,801,988 shares of common
stock outstanding (composed of (i) 26,930,730 shares of common stock outstanding as of
August 9, 2016 (according to the Form 10 Q filed by the issuer with the Securities and
Exchange Commission on August 10, 2016) and (ii) approximately 1,871,258 shares issuable
upon the conversion of certain convertible notes held by the Reporting Persons and certain
of their affiliates).