Deciphera Pharmaceuticals, Inc. and Zai Lab Limited Announce an Exclusive License Agreement for Ripretinib in Greater China

– Zai Lab to Lead the Development and Commercialization of Ripretinib
in Greater China –

– Deciphera To Receive $20 Million Upfront Cash Payment, up to $185
Million in Potential Future Milestones and Royalties –

– Deciphera Intends to Expand Ripretinib Development Program in
Gastrointestinal Stromal Tumors (GIST) by Potentially Adding China Sites
to the Ongoing Global Phase 3 INTRIGUE Study –

WALTHAM, Mass. & SHANGHAI–(BUSINESS WIRE)–Deciphera Pharmaceuticals, Inc. (NASDAQ:DCPH), a clinical-stage
biopharmaceutical company focused on addressing key mechanisms of tumor
drug resistance, and Zai Lab Ltd. (NASDAQ: ZLAB), a China and U.S.-based
innovative biopharmaceutical company, today announced an exclusive
license agreement to advance the development and commercialization of
ripretinib in Greater China (mainland China, Hong Kong, Macau and
Taiwan). Discovered and developed by Deciphera, ripretinib is an
investigational, oral, kinase switch control inhibitor in clinical
development for the treatment of GIST and other solid tumors driven by
KIT or PDGFRα.

Under the terms of the agreement, Deciphera will receive an upfront cash
payment of $20 million and will be eligible to receive up to $185
million in potential development and commercial milestone payments. In
addition, Zai Lab would pay Deciphera royalties from low to high teens
on annual net sales of ripretinib in Greater China. Zai Lab receives
exclusive regional development and commercialization rights for
ripretinib in Greater China. Zai Lab plans to leverage its regulatory
and clinical expertise to lead development of ripretinib in this
territory. Deciphera intends to expand the ongoing global Phase 3
INTRIGUE study, comparing ripretinib to sunitinib in second-line GIST
patients, and is currently assessing the addition of clinical trial
sites in China.

“We believe Zai Lab is the ideal partner for the development and
potential commercialization of ripretinib in Greater China,” said Steve
Hoerter, President and Chief Executive Officer of Deciphera. “Zai Lab’s
strong track record of rapidly progressing the development of innovative
product candidates will be a major asset in accelerating the development
of ripretinib in this area of the world. We are excited to be working
with Zai Lab to potentially offer patients in Greater China what we
believe is a much needed therapeutic option for the treatment of GIST.”

“We are very pleased to enter into this exclusive agreement for
ripretinib and look forward to partnering with Deciphera to potentially
bring ripretinib to GIST patients in Greater China,” said Dr. Samantha
Du, Chairman and Chief Executive Officer of Zai Lab. “Based on
encouraging clinical data reported to-date, we believe ripretinib, if
approved, could alter the treatment landscape for GIST patients.
Ripretinib has strong clinical and commercial synergies with our
existing pipeline of late stage gastrointestinal cancer programs. We are
committed to working with Deciphera to expand the global effort to bring
this important potential therapy to patients.”

“Each year in China, approximately 30,000 patients are newly diagnosed
with GIST, and an estimated 100,000 GIST patients are currently under
treatment,” said Dr. Lin Shen, Head of the Chinese Society of Clinical
Oncology GIST Expert Committee and Vice President of Clinical Oncology
at Beijing Cancer Hospital. “There are significant unmet medical needs
in GIST treatment especially for refractory patients after imatinib
therapy. Based on preliminary data, I believe that ripretinib has a
promising efficacy and safety profile that, if approved, could make it a
good potential option for GIST patients.”

About Ripretinib

Ripretinib is an investigational KIT and PDGFRα kinase switch control
inhibitor in clinical development for the treatment of KIT and/or
PDGFRα-driven cancers, including GIST, systemic mastocytosis, or SM, and
other cancers. Ripretinib was specifically designed to improve the
treatment of GIST patients by inhibiting a broad spectrum of mutations
in KIT and PDGFRα. Ripretinib is a KIT and PDGFRα inhibitor that blocks
initiating and secondary KIT mutations in exons 9, 11, 13, 14, 17, and
18, involved in GIST as well as the primary D816V exon 17 mutation
involved in SM. Ripretinib also inhibits primary PDGFRα mutations in
exons 12, 14 and 18, including the exon 18 D842V mutation, involved in a
subset of GIST.

About Deciphera Pharmaceuticals

Deciphera Pharmaceuticals (NASDAQ: DCPH) is a clinical-stage
biopharmaceutical company focused on improving the lives of cancer
patients by tackling key mechanisms of drug resistance that limit the
rate and/or durability of response to existing cancer therapies. Our
small molecule drug candidates are directed against an important family
of enzymes called kinases, known to be directly involved in the growth
and spread of many cancers. We use our deep understanding of kinase
biology together with a proprietary chemistry library to purposefully
design compounds that maintain kinases in a “switched off” or
inactivated conformation. These investigational therapies comprise
tumor-targeted agents designed to address therapeutic resistance causing
mutations and immuno-targeted agents designed to control the activation
of immunokinases that suppress critical immune system regulators, such
as macrophages. We have used our platform to develop a diverse pipeline
of tumor-targeted and immuno-targeted drug candidates designed to
improve outcomes for patients with cancer by improving the quality, rate
and/or durability of their responses to treatment.

About Zai Lab

Zai Lab (NASDAQ: ZLAB) is a China and U.S.-based innovative commercial
stage biopharmaceutical company focused on bringing transformative
medicines for cancer, autoimmune and infectious diseases to patients in
China and around the world. Zai Lab’s experienced team has secured
partnerships with leading global biopharma companies, generating a broad
pipeline of innovative drug candidates targeting the fast-growing
segments of China’s pharmaceutical market and addressing unmet medical
needs. Zai Lab’s vision is to become a fully integrated
biopharmaceutical company, discovering, developing, manufacturing and
commercializing its partners’ and its own products in order to impact
human health worldwide.

Availability of Other Information About Deciphera Pharmaceuticals

Investors and others should note that Deciphera Pharmaceuticals
communicates with its investors and the public using its company website
(www.deciphera.com),
including but not limited to investor presentations and scientific
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deemed to be material information. As a result, Deciphera
Pharmaceuticals encourages investors, the media and others interested in
Deciphera Pharmaceuticals to review the information that it posts on
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channels, or any other website that may be accessed from its website or
these channels, shall not be deemed incorporated by reference in any
filing under the Securities Act of 1933, as amended.

Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements within the
meaning of the Private Securities Litigation Reform Act of 1995, as
amended, including, without limitation, statements regarding our
expectations regarding our license with Zai Lab, future development and
potential commercialization of ripretinib in the Greater China territory
and the potential payments we may receive therefrom, and the potential
for ripretinib and our other drug candidates based on our kinase switch
control inhibitor platform to provide clinical benefit and treat cancers
such as GIST and other possible indications, enrollment for our INTRIGUE
pivotal Phase 3 study, including, without limitation, the potential for
and expectations with respect to opening China sites and enrolling China
patients and estimates of China GIST patients. The words “may,” “will,”
“could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,”
“believe,” “estimate,” “predict,” “project,” “potential,” “continue,”
“target” and similar expressions are intended to identify
forward-looking statements, although not all forward-looking statements
contain these identifying words. Any forward-looking statements in this
press release are based on management’s current expectations and beliefs
and are subject to a number of risks, uncertainties and important
factors that may cause actual events or results to differ materially
from those expressed or implied by any forward-looking statements
contained in this press release, including, without limitation, risks
and uncertainties related to our ability to derive the benefits and
mitigate the risks of any licensing transaction, the ability of our
licensee to execute a successful development and potential
commercialization of ripretinib in Greater China, our plans and ability
to expand our INTRIGUE study, successfully open sites and enroll
patients in China, the inherent uncertainty in estimating the number of
target patient populations, including without limitation GIST patients
in China, the delay of any current or planned clinical studies or the
development of our drug candidates, including ripretinib, rebastinib,
and DCC-3014, our advancement of multiple early-stage and later-stage
efforts, our ability to successfully demonstrate the efficacy and safety
of our drug candidates including in later-stage studies, the preclinical
and clinical results for our drug candidates, which may not support
further development of such drug candidates, our efforts to scale up and
manage drug product manufacturing, our ability to implement commercial
readiness, actions of regulatory agencies, any or all of which may
affect the initiation, timing and progress of clinical studies and other
risks identified in our SEC filings, including our Quarterly Report on
Form 10-Q for the quarter ended March 31, 2019, and subsequent filings
with the SEC. We caution you not to place undue reliance on any
forward-looking statements, which speak only as of the date they are
made. We disclaim any obligation to publicly update or revise any such
statements to reflect any change in expectations or in events,
conditions or circumstances on which any such statements may be based,
or that may affect the likelihood that actual results will differ from
those set forth in the forward-looking statements. Any forward-looking
statements contained in this press release represent our views only as
of the date hereof and should not be relied upon as representing its
views as of any subsequent date. We explicitly disclaim any obligation
to update any forward-looking statements.

Zai Lab Forward-Looking Statements

This press release contains statements about future expectations, plans
and prospects for Zai Lab. All statements, other than statements of
historical fact, included in this press release are forward-looking
statements, and are identified by words such as “anticipates”,
“believes”, “expects”, “plan” and other similar expressions. Such
statements constitute forward-looking statements within the meaning of
the Private Securities Litigation Reform Act of 1995. Forward-looking
statements are not statements of historical fact nor are they guarantees
or assurances of future performance. Forward-looking statements are
based on Zai Lab’s expectations and assumptions as of the date of this
press release and are subject to inherent uncertainties, risks and
changes in circumstances that may differ materially from those
contemplated by the forward-looking statements. Actual results may
differ materially from those indicated by such forward-looking
statements as a result of various important factors, including but not
limited to (1) Zai Lab’s ability to obtain additional future funding,
(2) Zai Lab’s results of clinical and pre-clinical development of its
drug candidates, (3) the content and timing of decisions made by the
relevant regulatory authorities regarding regulatory approvals of Zai
Lab’s drug candidates, (4) Zai Lab’s ability to generate revenue from
its drug candidates, and (5) other factors discussed in Zai Lab’s Annual
Report on Form 20-F for the fiscal year ended December 31, 2018 and its
other filings with the Securities and Exchange Commission. Zai Lab
anticipates that subsequent events and developments will cause Zai Lab’s
expectations and assumptions to change and undertakes no obligation to
publicly update or revise any forward-looking statements, whether as a
result of new information, future events or otherwise, except as may be
required by law. These forward-looking statements should not be relied
upon as representing Zai Lab’s views as of any date subsequent to the
date of this press release.

Contacts

Company:
Christopher J. Morl, Chief Business Officer
Deciphera
Pharmaceuticals, LLC
[email protected]
781-209-6418

Investor Relations:
Jen Robinson
Deciphera Pharmaceuticals,
Inc.
[email protected]
781-906-1112

Media:
Gina Nugent, The Yates Network
[email protected]
617-460-3579

Zai Lab:
Billy Cho, CFO
+86 137 6151 2501
[email protected]

Media: Nancie Steinberg / Robert Flamm
Burns McClellan, on behalf
of Zai Lab
212-213-0006, ext. 318 / 364, [email protected]
/ [email protected]

Investors: Lee Roth
Burns McClellan, on behalf of Zai Lab
212-213-0006,
ext. 331, [email protected]