NANOBIOTIX ANNOUNCES FIRST QUARTER OPERATIONAL AND FINANCIAL UPDATES Expanded clinical data set supporting tumor agnostic potential of NBTXR3 in presentation of first results in rectal cancer at ASCO-GI 202

NANOBIOTIX ANNOUNCES FIRST QUARTER OPERATIONAL AND FINANCIAL UPDATES

Paris, France; Cambridge, Massachusetts (USA); April 29, 2021 - NANOBIOTIX (Euronext : NANO - NASDAQ: NBTX - the Company''), a late-stage clinical

biotechnology company pioneering physics-based approaches to expand treatment possibilities for patients with cancer, today announced operational progress and cash position for the first quarter of 2021.

"The first quarter of this year saw further progress in development for Nanobiotix," said Laurent Levy, co-founder and chief executive officer of Nanobiotix. "We continue to generate data reinforcing our vision for

NBTXR3 as a first-in-class radioenhancer that could have a significant impact for patients across solid tumor types and therapeutic combinations. We are also encouraged that Sanofi has seen the potential of Curadigm's Nanoprimer and look forward to

a successful collaboration between the two companies in gene therapy."

Financial Updates Supporting Nanobiotix Development and Corporate Plans

Cash, cash equivalents, and short-term investments were 107.1 million at

March 31, 2021, supporting robust development plans into the second quarter of 2023, compared to 28m as of March 31st, 2020..

Following the decision to conclude a License and Collaboration agreement with PharmaEngine, Inc., the Company did not generate any revenue during the first quarter of 2021. This compares to 24k for the first quarter

of 2020, which resulted from cross-charges associated with the collaboration.

Clinical Activities and Achievements Advancing Solid Tumor-Agnostic and Combination-Agnostic Potential of NBTXR3

Corporate Activities and Achievements Expanding Value Creation Opportunities for Nanobiotix

Upcoming Corporate and Clinical Events in the Second Quarter of 2021

Updated Financial Agenda

NBTXR3 is a novel, potentially first-in-class oncology product composed of functionalized hafnium oxide nanoparticles that is administered via one-time intratumoral injection and activated by radiotherapy. The

product candidate's physical mechanism of action (MoA) is designed to induce significant tumor cell death in the injected tumor when activated by radiotherapy, subsequently triggering adaptive immune response and long-term anti-cancer memory. Given

the physical MoA, Nanobiotix believes that NBTXR3 could be scalable across any solid tumor that can be treated with radiotherapy and across any therapeutic combination, particularly immune checkpoint inhibitors.

NBTXR3 is being evaluated primarily in locally advanced head and neck squamous cell carcinoma (HNSCC). The company-sponsored phase I dose escalation and dose expansion study has produced consistently favorable safety

data and early signs of efficacy; and a phase III global registration is planned to launch in 2021. In February 2020, the United States Food and Drug Administration granted the regulatory Fast Track designation for the investigation of NBTXR3

activated by radiation therapy, with or without cetuximab, for the treatment of patients with locally advanced HNSCC who are not eligible for platinum-based chemotherapy-the same population being evaluated in the planned phase III.

Nanobiotix has also prioritized a company-sponsored Immuno-Oncology development program-a phase I clinical study evaluating NBTXR3 activated by radiotherapy in combination with anti-PD-1 checkpoint inhibitors for

patients with locoregional recurrent or recurrent/metastatic HNSCC and lung or liver metastases from any primary cancer eligible for anti-PD-1 therapy.

Given the Company's focus areas, and balanced against the scalable potential of NBTXR3, Nanobiotix has engaged in a strategic collaboration with strategy with world class partners to expand development of the product

candidate in parallel with its priority development pathways. Pursuant to this strategy, in 2019 The University of Texas MD Anderson Cancer Center engaged in a broad, comprehensive clinical research collaboration with Nanobiotix to sponsor several

phase I and phase II studies to evaluate NBTXR3 across tumor types and therapeutic combinations.

Nanobiotix is a late-stage clinical biotechnology company pioneering disruptive, physics-based therapeutic approaches to revolutionize treatment outcomes for millions of patients; supported by people committed to

making a difference for humanity. The company's philosophy is rooted in the concept of pushing past the boundaries of what is known to expand possibilities for human life.

Incorporated in 2003, Nanobiotix is headquartered in Paris, France and Cambridge, Massachusetts (United States). The company also has subsidiaries in France, Spain, and Germany. Nanobiotix has been listed on

Euronext: Paris since 2012 and completed a successful initial public offering (IPO) on the Nasdaq Global Select Market in New York City in December 2020. The company is one of only 7 dual-listed biotech companies with headquarters in France.

Nanobiotix is the owner of more than 30 umbrella patents associated with three (3) nanotechnology platforms: 1) applied to oncology; 2) applied to bioavailability and biodistribution; and 3) applied to disorders of

the central nervous system. The lion's share of the company's resources are devoted to the development of its lead product candidate-NBTXR3-which was born from its proprietary oncology platform and has already achieved market authorization in

Europe for the treatment of patients with soft tissue sarcoma under the brand name Hensify .

This press release contains certain "forward-looking" statements within the meaning of applicable securities laws, including the Private Securities Litigation Reform Act of 1995. Forward-looking

statements may be identified by words such as "at this time," "anticipate," "believe," "expect," "intend," "on track," "plan," "scheduled," and "will," or the negative of these and similar expressions. These forward-looking statements, which are

based on our management's current expectations and assumptions and on information currently available to management, include statements about the timing and progress of clinical trials, the timing of our presentation of data, the results of our

preclinical studies and their potential implications. Such forward-looking statements are made in light of information currently available to us and based on assumptions that Nanobiotix considers to be reasonable. However, these forward-looking

statements are subject to numerous risks and uncertainties, including with respect to the risk associated with the evolving nature of the duration and severity of the COVID-19 pandemic and governmental and regulatory measures implemented in

response to it. Furthermore, many other important factors, including those described in our Annual Report on Form 20-F filed with the U.S. Securities and Exchange Commission on April 7, 2021 under "Item 3.D. Risk Factors" and those set forth in the

universal registration document of Nanobiotix filed with the French Financial Markets Authority (Autorit des March s Financiers) on April 7, 2021 (a copy of which is available on www.nanobiotix.com), as well as other known and unknown risks and

uncertainties may adversely affect such forward-looking statements and cause our actual results, performance or achievements to be materially different from those expressed or implied by the forward-looking statements. Except as required by law, we

assume no obligation to update these forward-looking statements publicly, or to update the reasons why actual results could differ materially from those anticipated in the forward-looking statements, even if new information becomes available in the

First quarter 2021 Revenue: