UNITED STATES

SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

SCHEDULE 13G/A

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

o Rule 13d-1(b)

x Rule 13d-1(c)

o Rule 13d-1(d)

*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 the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose 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).

(1) Evidenced by (i) 1,140,325 shares of the Issuer’s Common Stock (“Shares”) and (ii) 87,028 Shares issuable upon the exercise of warrants to purchase Shares (the “Warrants). The Warrants contain an issuance limitation that prohibits the holder from exercising the Warrants to the extent that after giving effect to such issuance after exercise the holder (together with the holder’s affiliates, and any other persons acting as a group together with the holder or any of the holder’s affiliates), would beneficially own in excess of 9.99% of the Common Stock outstanding immediately after giving effect to the issuance of the Common Stock issuable upon exercise of the Warrants (the “Blocker”). As a result of the Blocker, as of the date hereof, 87,028 Shares are issuable upon exercise of the Warrants and such Shares are included in the beneficial ownership calculations reported herein.

(2) This percentage is calculated based upon 12,203,925 Shares outstanding as of November 10, 2015, as disclosed in the Issuer’s Form 10-Q filed with the Securities and Exchange Commission on November 12, 2015.

(1) Evidenced by (i) 1,140,325 shares of the Issuer’s Common Stock (“Shares”) and (ii) 87,028 Shares issuable upon the exercise of warrants to purchase Shares (the “Warrants). The Warrants contain an issuance limitation that prohibits the holder from exercising the Warrants to the extent that after giving effect to such issuance after exercise the holder (together with the holder’s affiliates, and any other persons acting as a group together with the holder or any of the holder’s affiliates), would beneficially own in excess of 9.99% of the Common Stock outstanding immediately after giving effect to the issuance of the Common Stock issuable upon exercise of the Warrants (the “Blocker”). As a result of the Blocker, as of the date hereof, 87,028 Shares are issuable upon exercise of the Warrants and such Shares are included in the beneficial ownership calculations reported herein.

(2) This percentage is calculated based upon 12,203,925 Shares outstanding as of November 10, 2015, as disclosed in the Issuer’s Form 10-Q filed with the Securities and Exchange Commission on November 12, 2015.

(1) Evidenced by (i) 1,140,325 shares of the Issuer’s Common Stock (“Shares”) and (ii) 87,028 Shares issuable upon the exercise of warrants to purchase Shares (the “Warrants). The Warrants contain an issuance limitation that prohibits the holder from exercising the Warrants to the extent that after giving effect to such issuance after exercise the holder (together with the holder’s affiliates, and any other persons acting as a group together with the holder or any of the holder’s affiliates), would beneficially own in excess of 9.99% of the Common Stock outstanding immediately after giving effect to the issuance of the Common Stock issuable upon exercise of the Warrants (the “Blocker”). As a result of the Blocker, as of the date hereof, 87,028 Shares are issuable upon exercise of the Warrants and such Shares are included in the beneficial ownership calculations reported herein.

(2) This percentage is calculated based upon 12,203,925 Shares outstanding as of November 10, 2015, as disclosed in the Issuer’s Form 10-Q filed with the Securities and Exchange Commission on November 12, 2015.

Cynapsus Therapeutics Inc.

828 Richmond Street West

Toronto, Ontario M6J 1C9

Canada

This Schedule 13G/A is being filed by each of the following persons (each a “Reporting Person”, and together, the “Reporting Persons”):

(i) OrbiMed Capital GP V LLC ("GP V")

(ii) OrbiMed Advisors LLC ("Advisors")

(iii) Samuel D. Isaly ("Isaly")

601 Lexington Avenue, 54th Floor

New York, NY 10022

Please refer to Item 4 on each cover sheet for each filing person.

Common Stock

23257Y859

GP V is the sole general partner of OrbiMed Private Investments V, LP ("OPI V"), which holds 1,227,353 shares of the Issuer's Common Stock ("Shares"). Advisors is an investment advisor in accordance with § 240.13d-1(b)(1)(ii)(E) and is the Managing Member of GP V. Isaly is the Managing Member of Advisors and a control person in accordance with § 240.13d-1(b)(1)(ii)(G). On the basis of these relationships, GP V, Advisors and Isaly may be deemed to share beneficial ownership of the Shares held by OPI V.

(a) Amount beneficially owned: See the response(s) to Item 9 on the attached cover page(s).

(b) Percent of class: See the response(s) to Item 11 on the attached cover page(s).

(c) Number of shares as to which the person has:

(i) Sole power to vote or to direct the vote:See the response(s) to Item 5 on the attached cover page(s).

(ii) Shared power to vote or to direct the vote: See the response(s) to Item 6 on the attached cover page(s).

(iii) Sole power to dispose or to direct the disposition of: See the response(s) to Item 7 on the attached cover page(s).

(iv) Shared power to dispose or to direct the disposition of: See the response(s) to Item 8 on the attached cover page(s).

See Item 4.

Item 7. Identification and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not Applicable.

Item 8. Identification and Classification of Members of the Group.

Not Applicable.