I-Mab Provides Business and Corporate Updates and Reports Financial Results for the Six Months Ended

I-Mab Provides Business and Corporate Updates and Reports

Results for the Six Months Ended June 30, 2021

I-Mab to host conference calls and webcasts on

August 31, 2021. A Mandarin session conference call will be held at 7:00 a.m. ET, and an English session conference call will be held at 8:00 a.m. ET.

SHANGHAI, China and GAITHERSBURG, Md., August 31, 2021 /PRNewswire/ I-Mab (the Company )

(Nasdaq: IMAB), a clinical stage biopharmaceutical company committed to the discovery, development and commercialization of novel biologics, today announced financial results for the six months ended June 30, 2021, and provided key business

During the reporting period, I-Mab has made remarkable progress in

its key business areas. Firstly, on the R&D front, the Company has rapidly advanced its globally competitive pipeline and achieved all critical clinical milestones as set in early 2021 for the key pipeline assets. More specifically, the

Company had seven clinical trials initiated or soon to be initiated, achieved five key data readout events for its differentiated investigational drugs, i.e. CD38 antibody felzartamab (TJ202/MOR202), CD47 antibody lemzoparlimab (TJC4), CD73 antibody

uliledlimab (TJD5), GM-CSF antibody plonmarlimab (TJM2) and novel IL-6 inhibitor olamkicept (TJ301). Furthermore, the Company has made significant progress in expanding

the current pipeline through the bi-specific antibody panel, where two lead assets have advanced to clinical trials in the U.S. in early 2021, as well as the next generation of novel antibody candidates

enabled by transformative technologies through collaborations. In this regard, the Company has successfully entered into five technology partnering deals to gain access to cutting-edge technologies to generate novel drug molecules with uniquely

acquired drug properties, including mRNA delivery, AI-guided targeting, cell-penetrating antibody and tumor-site activation. Secondly, on the corporate development front, the Company has met all

expected corporate milestones with respect to building its manufacturing facility in Hangzhou and its commercialization capabilities and preparation of the market launch of felzartamab. I-Mab is now globally

connected with six sites or offices in China and two R&D facilities in the U.S. Thirdly, during the reporting period, the Company has initiated its dual listing plan for the STAR Market in China and received multiple prestigious corporate

honors by the global biotech community and the capital market. The Company also made efforts to further strengthen its Board of Directors and Scientific Advisory Board with internationally reputable experts.

With the corporate focus and execution by our highly committed team, I-Mab has managed to have successfully

delivered outstanding results that have exceeded our original expectations set early this year, said Dr. Jingwu Zang, Founder and Chairman of I-Mab. We are thrilled by the achievements because

many of the milestones are critical as they have provided positive and enabling clinical data needed for the further development of the key pipeline assets. Looking ahead, we will have 19 clinical trials either ongoing or soon to be initiated in

both the United States and China by the end of this year, including our first BLA submission in Q4 2021. With these achievements, our pipeline is now not only innovative and globally competitive but also advanced with more assets moving towards

late-stage clinical trials and BLA.

The progress we have made so far has placed us firmly on track to deliver the rest of the critical

milestones and has effectively secured our overall development plan for the key assets such as felzartamab, eftansomatropin alfa, lemzoparlimab, uliledlimab, and plonmarlimab. We are very excited and confident to succeed in our journey to transition

from a clinical stage biotech now to a global biopharma within the next few years, Dr. Zang concluded.

Recent Pipeline Highlights and Upcoming Milestones

I-Mab has completed felzartamab 3L registrational trial, enabling the Company s first BLA submission in Q4 2021,

and currently manages two additional registrational trials, seven Phase 2 and eight Phase 1 clinical studies that are either ongoing or soon to be initiated in the U.S. and China. In parallel, a series of

pre-clinical programs representing the next generation of innovative assets, i.e. bi-specific antibodies as well as so called super antibodies , are under the

development and some will advance towards IND application in 2022.

Rapidly Advancing Clinical Development of the Late-Stage Assets for Near-Term Value

(1) Phase 3/pre-BLA assets

Felzartamab (TJ202/MOR202): A differentiated CD38 antibody for the treatment of multiple myeloma (MM) and potentially autoantibody-mediated

autoimmune diseases such as systemic lupus erythematosus (SLE). I-Mab has licensed development, manufacturing and commercialization rights for felzartamab in Greater China from MorphoSys.

Felzartamab for MM third-line treatment is on track for BLA submission in Q4 2021 and MM second-line registrational trial is on track. The Company plans to

submit a new IND application in Q3 2021 to explore the combination of felzartamab with another I-Mab clinical asset as a potential first-line treatment for MM. The rationale of this combination study is

strongly supported by the pre-clinical evidence.

Eftansomatropin alfa (TJ101): A differentiated long-acting growth hormone for pediatric growth

hormone deficiency (PGHD). Eftansomatropin alfa is the only rhGH in its proprietary fusion protein format (pure protein-based molecule) and is not chemically linked with PEG or other linkers. Its safety, tolerability, and efficacy have been well

demonstrated in a phase 2 clinical trial in the EU. I-Mab has the development, manufacturing, and commercial rights of eftansomatropin alfa in China from Genexine.

(2) Core clinical assets

Lemzoparlimab (TJC4): A highly differentiated CD47 antibody being developed through a comprehensive clinical development plan for hematologic

malignancies and solid tumors in China by I-Mab and globally by AbbVie. I-Mab s goal is to achieve the first registration of lemzoparlimab in its class in China and

facilitate global registration in collaboration with AbbVie, which leads global development and commercialization efforts. To achieve this goal, three clinical programs of lemzoparlimab are ongoing in parallel in both the U.S. and China, which will

potentially lead to one or two pivotal clinical trials in 2022.

Uliledlimab (TJD5): A highly differentiated CD73 antibody being developed for solid tumors. Phase 1 clinical trial conducted in

the U.S. was completed and the clinical data was presented at ASCO 2021 as described below. The Company is advancing the asset in phase 2 clinical trials in both the U.S. and China in selected tumor types in an effort to demonstrate clinical proof-of-concept. In parallel, the Company is exploring a potential global partnering deal.

Plonmarlimab (TJM2): A monoclonal antibody targeting human

granulocyte-macrophage colony-stimulating factor (GM-CSF), a cytokine that plays a critical role in acute and chronic inflammation. The Company recently carried out an interim analysis of its phase 2/3

clinical trial for the treatment of cytokine release syndrome (CRS) in patients with severe COVID-19 in the U.S. The results are reported below.

Efineptakin alfa (TJ107): The world s first and only long-acting recombinant

human interleukin-7 ( rhIL-7 ). This asset is clinically positioned as a monotherapy for the treatment of cancer patients with lymphopenia and as a combination

immunotherapy with a PD-1 or PD-L1 antibody for cancer treatment. I-Mab has the development, manufacturing, and commercial rights

of efineptakin alfa in Greater China from Genexine.

I-Mab is accelerating the clinical development of efineptakin

alfa by leveraging accumulative clinical data from multiple previous studies either as a monotherapy or in combination with checkpoint inhibitors in cancer patients, as conducted by I-Mab in China and Genexine

and NeoImmuneTech in South Korea and the U.S., respectively.

(3) Other clinical assets

Olamkicept (TJ301): A differentiated IL-6 blocker for ulcerative colitis and other autoimmune diseases. I-Mab entered into a license agreement with Ferring Pharmaceuticals to develop and commercialize olamkicept for Greater China and South Korea in 2016. On April 23, 2021, the Company and Ferring signed a memorandum

of understanding (MoU) to explore a possible collaboration to advance the development and commercialization of olamkicept in US and Canada, the European Union and Japan, if so agreed.

Enoblituzumab (TJ271): A

humanized B7-H3 antibody as an immuno-oncology treatment agent. As an anti-tumor agent, enoblituzumab works through a unique dual mechanism, i.e. ADCC and immune activation. Over the years, MacroGenics has

generated sufficient clinical data in cancer patients, which provide a critical guidance for further clinical development of enoblituzumab in the treatment of cancers. In addition, I-Mab s in-house work is geared towards delineating the combo strategy where enoblituzumab in combination with another treatment agent achieves synergism required for increased clinical efficacy. The Company s

development strategy is to move ahead with a combination therapy with pembrolizumab (Keytruda ) in selected cancer types, followed by new combo studies with other validated anti-tumor

agent(s). I-Mab licensed the development, manufacturing, and commercialization rights of enoblituzumab in Greater China from MacroGenics.

TJ210: A novel monoclonal antibody targeting C5aR1 to treat

cancers through myeloid-derived suppressor cells and modulation of tumor micro-environment in favor of enhanced anti-tumor immune response as a novel mechanism of action. The pre-clinical studies have provided

ample scientific evidence for the role of TJ210 in the treatment of cancers. Research is continuing, through in vitro and in vivo experimental systems, to identify and validate the most effective combo partner(s) for TJ210 to guide further clinical

development of TJ210. I-Mab owns the China rights from MorphoSys and co-develop the asset globally with MorphoSys.

Pipeline New-Comers as Bi-Specific Antibodies Driven by 2nd Wave Innovation and as Super Antibodies by 3rd Wave Innovation Through Transformative Technologies

(1) Bi-Specific Antibodies

The Company s bispecific antibodies are novel and designed to address the current unmet medical need in oncology where the majority of cancer patients

respond poorly to checkpoint inhibitors as their tumors are often characterized as immunologically cold tumor type. I-Mab s bi-specific antibodies are

structurally and functionally enabled to convert immunologically resistant cold tumors to immunologically responsive hot tumors by targeting multiple immune pathways so as to achieve synergistic anti-tumor activities. They

can be categorized into three antibody formats, namely PD-L1-based bispecific antibodies,

4-1BB-based conditional T cell engagers, and antibody-cytokine fusion or so-called immuno-cytokines. During the reporting period,

two lead bi-specific antibody assets have advanced to Phase 1 clinical trials in the U.S.

TJ-CD4B: A novel Claudin 18.2 and 4-1BB bispecific antibody capable of binding to tumor cells expressing Claudin 18.2, i.e., gastric cancer and pancreatic cancer cells, and stimulating intra-tumoral T cells by the

4-1BB arm designed to become functionally active only upon tumor engagement whilst silent elsewhere.

In June 2021, the first patient was dosed in a phase 1 clinical trial of TJ-CD4B in patients

with advanced or metastatic solid tumors in the U.S. To accelerate its clinical development, China sites will join the dose expansion part of the study in Q1 2022, enrolling patients with gastric cancer, gastroesophageal junction carcinoma,

esophageal adenocarcinoma, and pancreatic ductal adenocarcinoma.

TJ-L14B: A differentiated PD-L1-based bispecific antibody with the PD-L1 arm as the tumor-dependent T-cell activator and

the 4-1BB arm as the conditional T cell activator upon local tumor engagement.

In addition, other novel bispecific antibodies are currently under pre-clinical development and are expected to

advance to the clinical studies in 2022, including:

(2) Super Antibodies Enabled by Transformative Technologies

The Company recently launched a discovery initiative (the third wave innovation) to build a new portfolio of next generation of innovative drug candidates

characterized as novel super antibodies . These super antibodies are structurally different from monoclonal or bi-specific antibodies and uniquely enabled by transformative technologies such as an

mRNA-based antibody, masked antibody, cell-penetrating antibody and AI-guided cytokine drugs etc. The Company has gained the access to these cutting-edge technology platforms through collaborations as

described below. This growing new portfolio of novel drug candidates represents I-Mab s strong commitment to sustaining the global competitiveness of its pipeline through continued innovation and

complements the existing clinical programs.

The Company continues to drive innovation and scientific

leadership in immuno-oncology globally. These collaborations are expected to be followed by additional partnering deals that are under discussion, which are designed to propel the discovery engine to drive future pipeline growth.

Business Development and Partnering deals

the reporting period, the Company has completed 7 licensing and partnering deals that are geared to support the next generation of innovative assets. In addition, the Company is in discussion or business negotiation with potential partners on the

following opportunities: (1) Eftansomatropin alfa (TJ101) for a commercial partnering deal with a potential partner at a term-sheet stage, for which I-Mab expects to hold MAH and share in significant

sales profit; and (2) Other ongoing BD activities, focusing on in-licensing opportunities for the purpose of enriching the Company s initial commercial portfolio. In addition, the Company is

exploring a potential global partnering deal with respect to uliledlimab (TJD5) where I-Mab expects to retain the Greater China rights and grant ex-China rights to a potential global partner.

Transitioning from a Clinical Stage Biotech to Become a Global Biopharma

I-Mab has embarked on a journey to evolve from a clinical stage biotech today to a global biopharma within the next