Under the Securities Exchange Act of 1934
(Amendment No. 28)

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

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

With a copy to:

(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 which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(b)(3) or (4), check the following box o.

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-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 a prior cover page.

The information required on 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).

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This Amendment No. 28 is being filed jointly by Golden Meditech Stem Cells (BVI) Company Limited (“GM Stem Cells”), Golden Meditech Holdings Limited (“Golden Meditech”), Bio Garden Inc. (“Bio Garden”), Magnum Opus 3 International Holdings Limited (“MO3”) and Yuen Kam (“Mr. Kam”). GM Stem Cells, Golden Meditech, Bio Garden, MO3 and Mr. Kam are collectively referred to as the “Reporting Persons”.

This Amendment No. 28 amends and supplements the statement on Schedule 13D jointly filed with the Securities and Exchange Commission on July 9, 2009 by GM Stem Cells and Golden Meditech, as previously amended and supplemented by amendments to Schedule 13D filed on June 23, 2011, September 30, 2011, April 12, 2012, May 2, 2012, October 4, 2012, July 11, 2013, August 25, 2014, April 27, 2015, May 4, 2015, May 8, 2015, July 27, 2015, August 6, 2015, August 26, 2015, October 26, 2015, November 3, 2015, November 5, 2015, November 13, 2015, November 30, 2015, December 7, 2015, January 7, 2016, September 1, 2016, October 31, 2016, December 30, 2016, April 6, 2017, April 10, 2017, April 13, 2017 and November 14, 2017 (as so amended, the “Original Schedule 13D”). Capitalized terms used but not defined herein shall have the meanings ascribed to them in the Original Schedule 13D.

Item 4.     Purpose of Transaction

Item 4 of the Original Schedule 13D is hereby amended and supplemented by adding the following at the end thereof:

On January 31, 2018, the sale and purchase of the GM Shares was completed under the GM New Sale Agreement, as amended by the GM Supplemental Agreement. Upon and following such completion, GM Stem Cells ceased to own any of the GM Shares.

Item 5.     Material to be Filed as Exhibits.

Item 5 of the Original Schedule 13D is hereby amended and restated in its entirety to read as follows:

(a) — (b) As a result of the transactions described in Item 4, as of the date of this Amendment No. 28, each Reporting Person no longer beneficially owns any Ordinary Shares and, as such, each Reporting Person no longer has any voting or dispositive power over any Ordinary Shares.

(c) To the best knowledge of the Reporting Persons, except as described herein, none of the Reporting Persons has effected any transactions in the Ordinary Shares during the past 60 days prior to the filing of this Amendment No. 28.

(d) Not applicable.

(e) As a result of the transactions described in Item 4, as of the date of this Amendment No. 28, each of the Reporting Persons ceased to be the beneficial owner of more than five percent of any Ordinary Shares. Therefore, this Amendment No. 28 constitutes the final amendment to the Original Schedule 13D, as amended.

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SIGNATURE

After reasonable inquiry and to the best of its knowledge and belief, the undersigned certify that the information set forth in this statement is true, complete and correct.

Dated: January 31, 2018

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