Jacobio Pharmaceuticals : VOLUNTARY ANNOUNCEMENT JACOBIO RECEIVES US FDA INVESTIGATIONAL NEW DRUG CLEARANCE FOR KRAS G12C INHIBITOR

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JACOBIO PHARMACEUTICALS GROUP CO., LTD.

加 科 思 藥 業 集 團 有 限 公 司

(Incorporated in the Cayman Islands with limited liability)

(Stock code: 1167)

VOLUNTARY ANNOUNCEMENT

JACOBIO RECEIVES US FDA INVESTIGATIONAL

NEW DRUG CLEARANCE FOR KRAS G12C INHIBITOR

This announcement is made by JACOBIO PHARMACEUTICALS GROUP CO., LTD. (the "Company", together with its subsidiaries, the "Group") on a voluntary basis to inform the shareholders and potential investors of the Company of the business update of the Group.

The board (the "Board") of directors (the "Director(s)") of the Company is pleased to announce that the Food and Drug Administration of the United States (the "FDA") has approved the Investigational New Drug (the "IND") application of our KRAS G12C inhibitor JAB-21822.

JAB-21822 is the Company's in-house innovative allosteric inhibitor, which is designed to target KRAS G12C mutations. It will be used to treat advanced solid tumors with KRAS G12C somatic mutation, including but not limited to non-small cell lung cancer (NSCLC), colorectal cancer (CRC) and other advanced solid tumors.

KRAS is the most frequently mutated oncogene in human cancers. To date, there has been no approved and marketed KRAS G12C inhibitor globally. KRAS G12C mutations are found in approximately 11.0% of NSCLC patients, and smaller percentages of several other difficult-to-treat cancers. The global incidence of KRAS G12C mutations in patients with NSCLC, ovarian cancer, CRC and pancreatic cancer reached approximately 295,000 in 2019.

In our internal head-to-headpre-clinical animal studies, JAB-21822 has shown a superior pharmacokinetics (PK) profile and favorable tolerability as well as potential for a superior dosing profile in comparison with its competitors.

Scientific studies indicate that the combination of the KRAS G12C inhibitor with the SHP2 inhibitor results in increased anti-tumor activity based on their complementary mechanisms of action. SHP2 inhibitors (upstream of the RAS pathway) may potentially be the best combination therapy partners for KRAS inhibitors to address the adaptive drug resistance. The Company is one of the very few companies that has both the SHP2 inhibitor and KRAS G12C inhibitor. We are exploring in-house combination of these two drugs.

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Warning under Rule 18A.08(3) of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited: There is no assurance that the KRAS G12C inhibitor will ultimately be successfully developed and marketed by the Company. Shareholders of the Company and potential investors are advised to exercise caution when dealing in the shares of the Company.

On behalf of the Board

JACOBIO PHARMACEUTICALS GROUP CO., LTD.

Yinxiang WANG

Chairman

Hong Kong, May 3, 2021

As at the date of this announcement, the Board of Directors of the Company comprises Dr. Yinxiang WANG as Chairman and executive Director, Ms. Xiaojie WANG, Dr. Shaojing HU and Ms. Yunyan HU as executive Directors, Dr. Ting FENG, Ms. Yanmin TANG, Dr. Dong LYU and Dr. Te-li CHEN as non-executive Directors, and Dr. Ruilin SONG, Dr. Ge WU, Dr. Daqing CAI and Dr. Xiaoming WU as independent non-executive Directors.

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