Gracell Biotechnologies Doses First Patient in Phase 2 Portion of Registrational Phase 1/2 Clinical Trial Evaluating GC007g for Treatment of B-cell Acute Lymphoblastic Leukemia

Clinicaltrialassessing allogeneic,HLA-matched,donor-derived allogeneic CAR-T therapy

SAN DIEGO,Calif.,SUZHOU and SHANGHAI,China,Oct. 17,2022 --Gracell Biotechnologies Inc. ("Gracell" or the "Company",NASDAQ: GRCL),a global clinical-stage biopharmaceutical company dedicated to developing highly efficacious and affordable cell therapies for the treatment of cancer,today announced that the first patient has been dosed in the Phase 2 portion of its registrational Phase 1/2 clinical trial evaluating GC007g for the treatment of Relapsed/Refractory B-cell Acute Lymphoblastic Leukemia (r/r B-ALL) being conducted in China.

GC007g is Gracell's allogeneic,human leukocyte antigen (HLA)-matched,donor-derived,CD19-directed CAR-T cell therapy candidate under development for the treatment of a subset of B-ALL patients who relapsed after allogeneic human stem cell transplant (allo-HSCT). This donor-derived CAR-T approach has been designed for r/r B-ALL patients who may not be eligible for autologous CAR-T therapy due to poor cell fitness,infections,and other unsuitable conditions.

Data from the Phase 1 trial showedencouraging efficacy and a favorable safety profile. The registrational Phase 2 trial is being conducted in China and will furtherassess the safety and efficacy of GC007g in r/r B-ALL patients at the recommended Phase 2 dose.

"B-ALL patients that relapse after allo-HSCT therapy often face poor prognoses,and remain a patient population with a clear unmet medical need. Donor-derived CAR-T therapy could provide a new option to some of these patients who might be ineligible for other treatments including autologous CAR-T therapy," said Dr. Wendy Li,Chief Medical Officer of Gracell. "We believe GC007g is a potential first-in-class donor-derived allogeneic CAR-T therapy in China. GC007g is also Gracell's first therapeutic candidate to enter a registrational trial,marking an important milestone in our quest to transform cell therapy."

About GC007g

GC007g is an allogeneic CD19-targeted CAR-T cell therapy,derived from HLA-matched donors,under development for the treatment of r/r B-ALL patients who failed transplant and may not be eligible for autologous CAR-T therapy.

About ALL

Acute lymphoblastic leukemia (ALL) is a type of blood cancer characterized by proliferation of immature lymphocytes in the bone marrow,which can involve either T lymphocytes (T-ALL),or B lymphocytes (B-ALL). Globally,approximately 64,000 patients are diagnosed with ALL every year with an estimated 6,660 new cases to be diagnosed in the United States in 2022 [1]. B-ALL accounts for 75% of ALL diagnoses in adults.

[1]Data source: American Cancer Society

About Gracell

Gracell Biotechnologies Inc. ("Gracell") is a global clinical-stage biopharmaceutical company dedicated to discovering and developing breakthrough cell therapies. Leveraging its pioneering FasTCAR and TruUCAR technology platforms and SMART CARTTM technology module,Gracell is developing a rich clinical-stage pipeline of multiple autologous and allogeneic product candidates with the potential to overcome major industry challenges that persist with conventional CAR-T therapies,including lengthy manufacturing time,suboptimal cell quality,high therapy cost and lack of effective CAR-T therapies for solid tumors. For more information on Gracell,please visit www.gracellbio.com. Follow @GracellBio on LinkedIn.

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Media contacts

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Investor contacts

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