UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): October 22, 2015

AMARANTUS BIOSCIENCE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

(408) 737-2734

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Series H Preferred Stock and Warrants

 On October 23, 2015, Amarantus BioScience Holdings, Inc. (the “Company”) entered into a Securities Purchase Agreement (the “Series H SPA”) with an institutional investor for the sale of 330 (including 10% OID) shares of the Company’s 12% Series H Preferred Stock (the “Series H Preferred Stock”) and a warrant to purchase 140,250 shares of common stock (the “RD Warrant” and together with the Series H Preferred Stock, the “Securities”) in a registered direct offering (the “RD Offering”), subject to customary closing conditions.   The gross proceeds to the Company from the RD Offering were $290,000. Each share of Series H Preferred Stock has a stated value of $1,000 and is convertible into shares of common stock at an initial conversion price of the lower of (i) $2.50, subject to adjustment and (ii) 75%, subject to adjustment, of the lowest volume weighted average price, or VWAP, during the fifteen (15) Trading Days immediately prior to the date a conversion notice is sent to the Company by a holder, at any time at the option of the holder.

The RD Warrant is exercisable at any time on or after the earlier to occur of (i) all shares of common stock underlying the RD Warrant are registered for resale under the Securities Act of 1933, and (ii) the date six (6) months from October 23, 2015 (the earlier to occur of (i) and (ii), the “Initial Exercise Date”) and on or prior to the close of business on the five-year anniversary of the Initial Exercise Date at an exercise price of $2.00 per share.

The Securities were issued pursuant to a prospectus supplement dated October 27, 2015 filed with the Securities and Exchange Commission on October 27, 2015, in connection with a takedown from the Registration Statement on Form S-3 (File No. 333-203845), which was declared effective by the SEC on May 22, 2015.

Previously on October 16, 2015, the Company entered into a Series H SPA with an institutional investor for the sale of 165 shares of Series H Preferred Stock and RD warrant for the purchase of 70,125 shares of common stock. The gross proceeds to the Company from this offering were $140,000. The Securities were issued pursuant to a prospectus supplement dated October 19, 2015 filed with the Securities and Exchange Commission on October 197, 2015, in connection with a takedown from the Registration Statement on Form S-3 (File No. 333-203845), which was declared effective by the SEC on May 22, 2015

On October 22, 2015, David Lowe resigned as a member of the Board of Directors of the Company, effective immediately, for personal reasons and after terminating the consulting agreement dated November 1, 2014 by and between the Company and NeuroAssets Sarl. Dr. Lowe is President and CEO of NeuroAssets Sarl.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.