MaxCyte Regulatory News (MXCT)

MaxCyte, Inc.

("MaxCyte" or the "Company")

MaxCyte Commences Dosing in First Clinical Trial in Solid Tumours

First patient dosed in Phase I clinical study to evaluate MaxCyte's lead CAR therapeutic

in ovarian cancer and peritoneal mesothelioma

Gaithersburg, Maryland - 10 October 2018: MaxCyte (LSE: MXCT, MXCR), the global cell-based medicines and life sciences company, announced today that the first patient has been dosed in its Phase I dose-escalation clinical trial in the United States with the Company's lead wholly-owned chimeric antigen receptor (CAR) therapeutic candidate, MCY-M11. The study is designed to evaluate MCY-M11, a mesothelin targeting CAR, in individuals with relapsed/refractory ovarian cancer and peritoneal mesothelioma.

"The initiation of patient dosing in our first clinical trial with our lead CAR therapeutic candidate is a significant milestone for MaxCyte, validating our streamlined manufacturing process for clinical use," said MaxCyte CEO Doug Doerfler. "We are extremely pleased to have very experienced investigators at two leading clinical centers conducting this study in solid tumours. We believe this clinical trial will further demonstrate the potential of our proprietary CARMA™ (CAR therapeutic) autologous cell-therapy platform to develop meaningful, targeted cell-based immune therapies."

CARMA utilises messenger RNA (mRNA) as the delivery vehicle for a CAR transfected into freshly isolated peripheral blood mononuclear cells, allowing for rapid manufacture and delivery back to the patient, without the need for a viral component or cell expansion. The CARMA platform provides a cell therapy with transient expression, enabling repeat dosing and with the potential to reduce the cost and minimize adverse side-effects seen in viral-based CAR therapies.

"In recent years we have seen tremendous progress in the treatment of some types of cancer, but there remains a significant need to explore novel treatments that may benefit patients," said Claudio Dansky Ullmann, MD, MaxCyte Chief Medical Officer. "Individuals with advanced and relapsed ovarian cancer or peritoneal mesothelioma have limited effective therapeutic options today. MCY-M11 is an exciting new approach with the potential to improve outcomes for these patients. We look forward to the continued progress of this first clinical study."

About the Phase I Clinical Trial

The multi-center, non-randomized, open label, dose-escalation Phase I clinical trial will evaluate the safety and effectiveness of intraperitoneal infusions of MCY-M11 in individuals with platinum-resistant high-grade serous adenocarcinoma of the ovary, primary peritoneum or fallopian tube, or individuals with advanced peritoneal mesothelioma with recurrence after prior chemotherapy. MaxCyte anticipates approximately 15 study participants will be enrolled across the two clinical sites participating in the study (the National Cancer Institute at the National Institutes of Health (NIH) and Washington University at St. Louis). More information about the study can be found at https://clinicaltrials.gov/ct2/show/NCT03608618?term=maxcyte&rank=1.

About the CARMA (CAR Therapy) Platform

CARMA is MaxCyte's unique and proprietary CAR therapy platform in immuno-oncology. The platform is used to develop CAR therapies for a broad range of cancer indications. It offers the potential to deliver autologous cell therapies across a wide range of targets with a much quicker turnaround to the patient than traditional autologous cell therapies, and with repeat dosing that may reshape the endogenous immune system of these patients towards a more effective antitumor response. More information on MaxCyte's CARMA programme is available at https://www.maxcyte.com/car/.

About MaxCyte

MaxCyte is a global cell-based medicines and life sciences company applying its patented cell engineering technology to help patients with high unmet medical needs in a broad range of conditions. MaxCyte is developing novel CARMA therapies for its own pipeline. CARMA is MaxCyte's mRNA-based proprietary platform for autologous cell therapy. In addition, through its core business, the Company leverages its Flow Electroporation® Technology to enable its partners across the biopharmaceutical industry to advance the development of innovative medicines, particularly in cell therapy, including gene editing and immuno-oncology. The Company has placed its cutting-edge flow electroporation instruments worldwide, with all of the top ten global biopharmaceutical companies, has more than 55 partnered programme licences in cell therapy including more than 25 licensed for clinical use. With its robust delivery technology, MaxCyte helps its partners to unlock the full potential of their products. For more information, visit www.maxcyte.com

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