CRISPR Therapeutics Provides Business Update and Reports Second Quarter 2020 Financial Results -Dosing re-initiated in clinical trials of CTX001 for patients with severe hemoglobinopathies- - CTX001 has received orphan d

CRISPR Therapeutics Provides Business Update and Reports Second Quarter 2020 Financial Results

-Dosing re-initiated in clinical trials of CTX001 for patients with severe hemoglobinopathies-

- CTX001 has received orphan drug designation from the U.S. FDA for sickle cell disease (SCD)-

-Expands regenerative medicine portfolio through a collaboration with University Health Network (UHN), gaining access to hepatocytes-

ZUG, Switzerland and CAMBRIDGE, Mass., July 27, 2020 -- CRISPR Therapeutics (Nasdaq: CRSP), a biopharmaceutical company focused on creating transformative gene-based medicines for serious diseases, today reported financial results for the second quarter ended June 30, 2020.

"We continue to make substantial progress driving our multiple, ongoing clinical development programs. Enrollment in our immuno-oncology trials is ongoing, and we've re-initiated dosing in our CTX001 trials," said Samarth Kulkarni, Ph.D., Chief Executive Officer of CRISPR Therapeutics. "Further, we expect to report data from our CTX001 program targeting hemoglobinopathies and our CTX110 program later this year. Despite the challenges posed by COVID-19, we continue to execute on our programs and remain focused on our commitment to patients and their families."

Recent Highlights and Outlook

Second Quarter 2020 Financial Results

CTX001 is an investigational ex vivo CRISPR gene-edited therapy that is being evaluated for patients suffering from TDT or severe SCD in which a patient's hematopoietic stem cells are engineered to produce high levels of fetal hemoglobin (HbF; hemoglobin F) in red blood cells. HbF is a form of the oxygen-carrying hemoglobin that is naturally present at birth and is then replaced by the adult form of hemoglobin. The elevation of HbF by CTX001 has the potential to alleviate transfusion requirements for TDT patients and painful and debilitating sickle crises for SCD patients.

CTX001 is being developed under a co-development and co-commercialization agreement between CRISPR Therapeutics and Vertex.

CTX110 is a healthy donor-derived gene-edited allogeneic CAR-T therapy targeting cluster differentiation 19, or CD19, for the treatment of CD19+ malignancies. A wholly-owned asset of CRISPR Therapeutics,

CTX110 is being investigated in a clinical trial designed to assess the safety and efficacy of CTX110 for the treatment of relapsed or refractory B-cell malignancies. The multi-center, open-label clinical trial is designed to enroll up to 131 patients and investigate several dose levels of CTX110.

CTX120 is a healthy donor-derived gene-edited allogeneic CAR-T therapy targeting B-cell maturation antigen, or BCMA. A wholly-owned asset of CRISPR Therapeutics, CTX120 is being investigated in a clinical trial designed to assess the safety and efficacy of CTX120 for the treatment of relapsed or refractory multiple myeloma. The multi-center, open-label clinical trial is designed to enroll up to 88 patients and investigate several dose levels of CTX120.

CTX130 is a healthy donor-derived gene-edited allogeneic CAR-T therapy targeting cluster of differentiation 70, or CD70, an antigen expressed on various solid tumors and hematologic malignancies. CTX130 is being developed for the treatment of both solid tumors, such as renal cell carcinoma, and T-cell and B-cell hematologic malignancies. A wholly-owned asset of CRISPR Therapeutics, CTX130 is being investigated in two independent clinical trials that are designed to assess the safety and efficacy of CTX130 for the treatment of relapsed or refractory renal cell carcinoma and various subtypes of lymphoma, respectively. The multi-center, open-label clinical trial investigating CTX130 for the treatment of relapsed or refractory renal cell carcinoma is designed to enroll approximately 95 patients and investigate several dose levels of CTX130. The multi-center, open-label clinical trial investigating CTX130 for the treatment of various lymphomas is designed to enroll approximately 46 patients and investigate several dose levels of CTX130.

About CRISPR Therapeutics

CRISPR Therapeutics is a leading gene editing company focused on developing transformative gene-based medicines for serious diseases using its proprietary CRISPR/Cas9 platform. CRISPR/Cas9 is a revolutionary gene editing technology that allows for precise, directed changes to genomic DNA. CRISPR Therapeutics has established a portfolio of therapeutic programs across a broad range of disease areas including hemoglobinopathies, oncology, regenerative medicine and rare diseases. To accelerate and expand its efforts, CRISPR Therapeutics has established strategic partnerships with leading companies including Bayer, Vertex Pharmaceuticals and ViaCyte, Inc. CRISPR Therapeutics AG is headquartered in Zug, Switzerland, with its wholly-owned U.S. subsidiary, CRISPR Therapeutics, Inc., and R&D operations based in Cambridge, Massachusetts, and business offices in San Francisco, California and London, United Kingdom. For more information, please visit www.crisprtx.com.

CRISPR Forward-Looking Statement

This press release may contain a number of "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including statements made by Dr. Kulkarni in this press release, as well as statements regarding CRISPR Therapeutics' expectations about any or all of the following: (i) the safety, efficacy and clinical progress of CRISPR Therapeutics' various clinical programs including CTX001, CTX110, CTX120 and CTX130; (ii) the status of clinical trials (including, without limitation, the expected timing of data releases and activities at clinical trial sites), development timelines and discussions with regulatory authorities related to product candidates under development by CRISPR Therapeutics and its collaborators; (iii) the number of patients that will be evaluated, the anticipated date by which enrollment will be completed and the data that will be generated by ongoing and planned clinical

trials, including expectations regarding the data that was presented at the European Hematology Association's virtual congress, and the ability to use that data for the design and initiation of further clinical trials; (iv) potential impacts due to the coronavirus pandemic; (v) the actual or potential benefits of FDA designations, such as orphan drug, fast track and regenerative medicine advanced therapy, and European equivalents; (vi) CRISPR Therapeutics' ability to build out new facilities in anticipated timeframes and need for infrastructure expansion; (vii) the intellectual property coverage and positions of CRISPR Therapeutics, its licensors and third parties as well as the status and potential outcome of proceedings involving any such intellectual property; (viii) the sufficiency of CRISPR Therapeutics' cash resources; (ix) the expected benefits of CRISPR Therapeutics' collaborations; and (x) the therapeutic value, development, and commercial potential of CRISPR/Cas9 gene editing technologies and therapies. Without limiting the foregoing, the words "believes," "anticipates," "plans," "expects" and similar expressions are intended to identify forward-looking statements. You are cautioned that forward-looking statements are inherently uncertain. Although CRISPR Therapeutics believes that such statements are based on reasonable assumptions within the bounds of its knowledge of its business and operations, forward-looking statements are neither promises nor guarantees and they are necessarily subject to a high degree of uncertainty and risk. Actual performance and results may differ materially from those projected or suggested in the forward-looking statements due to various risks and uncertainties. These risks and uncertainties include, among others: the potential impacts due to the coronavirus pandemic such as (x) delays in regulatory review, manufacturing and supply chain interruptions, adverse effects on healthcare systems and disruption of the global economy; (y) the timing and progress of clinical trials, preclinical studies and other research and development activities; and (z) the overall impact of the coronavirus pandemic on its business, financial condition and results of operations; the potential for initial and preliminary data from any clinical trial (including CTX001, CTX110, CTX120 and CTX130) not to be indicative of final trial results; the risk that the initial data from a limited number of patients (as is the case with CTX001 at this time) may not be indicative of results from the full planned study population; the outcomes for each CRISPR Therapeutics' planned clinical trials and studies may not be favorable; that one or more of CRISPR Therapeutics' internal or external product candidate programs will not proceed as planned for technical, scientific or commercial reasons; that future competitive or other market factors may adversely affect the commercial potential for CRISPR Therapeutics' product candidates; uncertainties inherent in the initiation and completion of preclinical studies for CRISPR Therapeutics' product candidates; availability and timing of results from preclinical studies; whether results from a preclinical trial will be predictive of future results of the future trials; uncertainties about regulatory approvals to conduct trials or to market products; uncertainties regarding the intellectual property protection for CRISPR Therapeutics' technology and intellectual property belonging to third parties, and the outcome of proceedings (such as an interference, an opposition or a similar proceeding) involving all or any portion of such intellectual property; and those risks and uncertainties described under the heading "Risk Factors" in CRISPR Therapeutics' most recent annual report on Form 10-K, quarterly report on Form 10-Q and in any other subsequent filings made by CRISPR Therapeutics with the U.S. Securities and Exchange Commission, which are available on the SEC's website at www.sec.gov. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date they are made. CRISPR Therapeutics disclaims any obligation or undertaking to update or revise any forward-looking statements contained in this press release, other than to the extent required by law.

CRISPR THERAPEUTICS word mark and design logo, CTX001TM, CTX110TM, CTX120TM, and CTX130TM are trademarks and registered trademarks of CRISPR Therapeutics AG. All other trademarks and registered trademarks are the property of their respective owners.

CRISPR Therapeutics AG

Condensed Consolidated Statements of Operations

(Unaudited, In thousands except share data and per share data)

CRISPR Therapeutics AG

Condensed Consolidated Balance Sheets Data

(Unaudited, in thousands)

WCG on behalf of CRISPR