MaxCyte, Inc. - Exercise of options and PDMR dealing

ROCKVILLE - MaxCyte Inc., (Nasdaq: MXCT; LSE: MXCT), a leading, cell-engineering focused company providing enabling platform technologies to advance the discovery, development and commercialization of next-generation cell-based therapeutics and innovative bioprocessing applications, announces that on 26 March 2024, as per a filing lodged with the U.S. Securities and Exchange Commission, John Johnston, a Non-Executive Director of the Company, exercised options over 5,000 shares of common stock of $0.01 of the Company ( Common Stock ) ( Exercise ) in aggregate.

The 5,000 new shares of Common Stock were issued pursuant to the Company s existing its block admission facility and were sold by John Johnston at a price range between $4.370 and $4.430 per Common Stock ( Sale ). The sold shares represent approximately 1.7% of John Johnston s total equity and option holdings in the Company s stock capital, respectively.

Following the Exercise and Sale, John Johnston holds 120,583 shares of Common Stock representing 0.1% of the issued stock capital of the Company. Following the Exercise, John Johnston holds a further 162,217 options over Common Stock.

The sales and option exercises were effected pursuant to a Rule 10b5-1 trading plan adopted by John Johnston on 28 March 2023 relating solely to the sale of shares acquired from exercise of options that expire on 4 March 2029.

Contact:

David Deuchler

Tel: +1 415-937-5400

Email: ir@maxcyte.com

Chris Welsh

Tel: +44 (0)203 709 5700

Email: maxcyte@consilium-comms.com

About MaxCyte

At MaxCyte, we pursue cell engineering excellence to maximize the potential of cells to improve patients lives. We have spent more than 20 years honing our expertise by building best-in-class platforms, perfecting the art of the transfection workflow, and venturing beyond today s processes to innovate tomorrow s solutions. Our ExPERT platform, which is based on our Flow Electroporation technology, has been designed to support the rapidly expanding cell therapy market and can be utilized across the continuum of the high-growth cell therapy sector, from discovery and development through commercialization of next-generation, cell-based medicines. The ExPERT family of products includes: four instruments, the ATx, STx, GTx and VLx; a portfolio of proprietary related processing assemblies or disposables and software protocols, all supported by a robust worldwide intellectual property portfolio. By providing our partners with the right technology platform, as well as scientific, technical and regulatory support, we aim to guide them on their journey to transform human health.