Genscript Biotech : VOLUNTARY ANNOUNCEMENT - RESEARCH AND DEVELOPMENT UPDATE

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Genscript Biotech Corporation

金斯瑞生 物科 技 股份 有限 公 司 *

(Incorporated in the Cayman Islands with limited liability)

(Stock code: 1548)

VOLUNTARY ANNOUNCEMENT

RESEARCH AND DEVELOPMENT UPDATE

Reference is made to the voluntary announcements of Genscript Biotech Corporation (the "Company" , together with its subsidiaries, the "Group" ) dated 28 October 2016, 14 May 2017, 6 June 2017, 19 September 2017, 1 November 2018, 4 December 2018, 4 April 2019, 16 April 2019 and 28 August 2019. The board (the "Board" ) of directors (the "Directors" ) of the Company is pleased to announce that Legend Biotech Corporation, a subsidiary of the Company, will present key clinical development of LCAR-B38M and JNJ-68284528(JNJ-4528) at the American Society of Hematology ( "ASH" ) meeting on December 7, 2019 and December 9, 2019, including the long term follow-up clinical development of the LEGEND-2 study in China, as well as the initial data from CARTITUDE-1 study in the United States which builds upon the first-in-humanLEGEND-2 study.

LCAR-B38M and JNJ-68284528(JNJ-4528) are investigational B-cell maturation antigen ( "BCMA" ) chimeric antigen receptor T-cell ( "CAR-T" ) therapy being studied in relapsed and/ or refractory multiple myeloma ( "RRMM" ). Abstracts of the data from the above studies will be presented during the following dates and times. Updated data for CARTITUDE-1 study will be presented during the oral presentations.

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		Date, Time and
Study	Abstract#/Title	Presenting Author
CARTITUDE-1	ABSTRACT #577: Results from	Oral Presentation
(MMY2001,	CARTITUDE-1: a Phase 1b/2	Monday, December 9, 7:00
NCT03548207),	study of JNJ-4528, a CAR-T cell	am
United States	therapy directed against BCMA,	Presented by D Madduri
	in patients with RRMM
	ABSTRACT #928:	Oral Presentation
	Translational analysis from	Monday, December 9, 7:00
	CARTITUDE-1, an ongoing	pm
	Phase 1b/2 study of JNJ-4528	Presented by E Zudaire
	BCMA-targetedCAR-T cell
	therapy in RRMM, indicates
	preferential expansion of CD8+
	T Cell central memory cell
	subset
LEGEND-2	ABSTRACT #579: Long-term	Oral Presentation
(NCT03090659), China	follow-up of a Phase 1, first-	Monday, December	9,	7:30
	in-humanopen-label study of	am
	LCAR-B38M, a structurally	Presented by BY Wang
	differentiated CAR-T cell
	therapy targeting BCMA, in
	patients with RRMM
	ABSTRACT #1858: Updated	Poster Presentation
	Phase 1 results of a first-in-	Saturday, December	7,	5:30
	human open-label study of	pm
	LCAR-B38M, a structurally	Presented by LJ Chen
	differentiated CAR-T cell
	therapy targeting BCMA

In February 2019, Office of Orphan Product Development from the Food and Drug Administration of the United States granted the Orphan Drug Designation for JNJ-4528(JNJ-4528)/LCAR-B38M. On April 3, 2019, the European Medicines Agency ( "EMA" ) granted a "PRIority MEdicines" ( "PRIME" ) designation to Janssen-Cilag International N.V. for JNJ-4528 which was supported by results from the Phase 1b/2 CARTITUDE-1 study (NCT03548207) and the Phase 1/2 LEGEND-2 study (NCT03090659) evaluating LCAR-B38M in RRMM. For details, please refer to the voluntary announcement of the Company dated April 4, 2019 and the annual report of year 2018 of the Company dated April 15, 2019.

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About LEGEND-2

LEGEND-2 (NCT03090659) is an ongoing single-arm,open-label Phase 1/2 study of 74 patients being conducted at four participating hospitals in China evaluating the efficacy and safety of LCAR-B38M for the treatment of relapsed or refractory multiple myeloma.

About CARTITUDE-1

In the United States, JNJ-4528 is currently being investigated in the Phase 1b/2 CARTITUDE-1 (MMY2001, NCT03548207) registration study for the treatment of patients with multiple myeloma who have received at least three prior lines of therapy or are double refractory to a proteinase inhibitor ( "PI" ) and immunomodulatory drug ( "IMiD" ), received a PI, an IMiD, and anti-CD38 antibody and documented disease progression within 12 months of starting the most recent therapy.

Shareholders and potential investors of the Company are advised to pay attention to investment risks and exercise caution when they deal or contemplate dealing in the securities of the Company.

By order of the Board

Genscript Biotech Corporation

Zhang Fangliang

Chairman and Chief Executive Officer

Hong Kong, 7 November 2019

As at the date of this announcement, the executive Directors are Dr. Zhang Fangliang, Ms. Wang Ye and Mr. Meng Jiange; the non-executive Directors are Dr. Wang Luquan, Mr. Pan Yuexin and Ms. Wang Jiafen; and the independent non-executive Directors are Mr. Guo Hongxin, Mr. Dai Zumian and Mr. Pan Jiuan.

• For identification purposes only

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