Galera Reports First Quarter 2021 Financial Results and Recent Accomplishments Phase 3 ROMAN trial in severe oral mucositis expected to complete enrollment in 1H21; topline data expected in 2H21 Recently announced near d

Galera Reports First Quarter 2021 Financial Results and Recent Accomplishments

Phase 3 ROMAN trial in severe oral mucositis expected to complete enrollment in 1H21; topline data expected in 2H21

Recently announced near doubling of median overall survival observed in placebo-controlled pancreatic cancer trial

Phase 2b pancreatic cancer trial, GRECO-2, expected to commence enrollment in 1H21

MALVERN, Pa. May 11, 2021 Galera Therapeutics, Inc. (Nasdaq: GRTX), a clinical-stage biopharmaceutical company focused

on developing and commercializing a pipeline of novel, proprietary therapeutics that have the potential to transform radiotherapy in cancer, today announced financial results for the first quarter ended March 31, 2021, and highlighted recent

corporate accomplishments.

Galera is off to a strong start in 2021, as we continue to progress our clinical oncology programs in radiation-induced

severe oral mucositis (SOM), locally advanced pancreatic cancer (LAPC) and non-small cell lung cancer (NSCLC) with our dismutase mimetics, said Mel Sorensen, M.D., President and CEO of Galera.

We recently reported updated data from our placebo-controlled Phase 1/2 pilot trial, in which a near doubling of median overall survival was observed in patients with pancreatic cancer. Building on the positive results from this trial, we

anticipate initiating a Phase 2b trial in the first half of 2021 in patients with LAPC, with overall survival as the primary endpoint. Importantly, we look forward to announcing topline data in the pivotal Phase 3 trial in SOM and potential

regulatory approval and commercialization of avasopasem, our lead dismutase mimetic product candidate.

Recent Corporate Highlights

Severe Oral Mucositis (SOM)

Locally Advanced Pancreatic Cancer (LAPC)

Non-Small Cell Lung Cancer (NSCLC)

First Quarter 2021 Financial Highlights

About Galera Therapeutics

Galera Therapeutics, Inc. is a clinical-stage biopharmaceutical company focused on developing and commercializing a pipeline of novel, proprietary therapeutic

candidates that have the potential to transform radiotherapy in cancer. Galera s lead product candidate is avasopasem manganese (GC4419,

also referred to as avasopasem), a selective small molecule dismutase mimetic initially being developed for the reduction of radiation-induced severe oral mucositis (SOM). Avasopasem is being

studied in the Phase 3 ROMAN trial to assess its ability to reduce the incidence and severity of SOM induced by radiotherapy in patients with locally advanced head and neck cancer (HNC), its lead indication. It is also being studied in the EUSOM

Phase 2a multi-center trial in Europe assessing the safety of avasopasem in patients with HNC undergoing standard-of-care radiotherapy, the AESOP Phase 2a trial to

assess its ability to reduce the incidence of esophagitis induced by radiotherapy in patients with lung cancer, and a Phase 2 trial in hospitalized patients who are critically ill with COVID-19. A pilot Phase

1/2 trial of avasopasem in combination with stereotactic body radiation therapy (SBRT) in patients with locally advanced pancreatic cancer (LAPC) has completed enrollment and reported updated results, with

follow-up ongoing. The FDA granted Fast Track and Breakthrough Therapy designations to avasopasem for the reduction of SOM induced by radiotherapy, with or without systemic therapy. Galera s second

dismutase mimetic product candidate, GC4711, is being developed specifically to augment the anti-cancer efficacy of SBRT, and is currently being studied in the GRECO-1 Phase 1/2 trial in combination with SBRT

in patients with non-small cell lung cancer. Galera also intends to initiate the GRECO-2 Phase 2b trial of GC4711 in combination with SBRT in patients with LAPC. Galera

is headquartered in Malvern, PA. For more information, please visit www.galeratx.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in

this press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation statements regarding: expectations surrounding our growth and the continued advancement of our product

pipeline, including plans for the commercial launch of avasopasem; the potential, safety, efficacy, and regulatory and clinical development of Galera s product candidates; plans and timing for the commencement of and the release of data from

Galera s clinical trials; expected payments from Blackstone; and the sufficiency of Galera s cash, cash equivalents and short-term investments. These forward-looking statements are based on management s current expectations. These

statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause Galera s actual results, performance or achievements to be materially different from any future

results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: Galera s limited operating history; anticipating continued losses for the foreseeable future; needing

substantial funding and the ability to raise capital; Galera s dependence on avasopasem manganese (GC4419); uncertainties inherent in the conduct of clinical trials; difficulties or delays enrolling patients in clinical trials; the FDA s

acceptance of data from clinical trials outside the United States; undesirable side effects from Galera s product candidates; risks relating to the regulatory approval process; failure to capitalize on more profitable product candidates or

indications; ability to receive or maintain Breakthrough Therapy Designation or Fast Track Designation for product candidates; failure to obtain regulatory approval of product candidates in the United States or other jurisdictions; ongoing

regulatory obligations and continued regulatory review; risks related to commercialization; risks related to competition; ability to retain key employees and manage growth; risks related to intellectual property; inability to maintain collaborations

or the failure of these collaborations; Galera s reliance on third parties; the possibility of system failures or security breaches; liability related to the privacy of health information obtained from clinical trials and product liability

lawsuits; unfavorable pricing regulations, third-party reimbursement practices or healthcare reform initiatives; environmental, health and safety laws and regulations; the impact of the COVID-19 pandemic on

Galera s business and operations, including preclinical studies and clinical trials, and general economic conditions; risks related to ownership of Galera s common stock; and significant

costs as a result of operating as a public company. These and other important factors discussed under the caption Risk Factors in Galera s Annual Report on Form 10-K for the year ended December 31, 2020 filed with the U.S. Securities and Exchange Commission (SEC) and Galera s other filings with the SEC could cause actual results to differ materially from those

indicated by the forward-looking statements made in this press release. Any forward-looking statements speak only as of the date of this press release and are based on information available to Galera as of the date of this release, and Galera

assumes no obligation to, and does not intend to, update any forward-looking statements, whether as a result of new information, future events or otherwise.

Galera Therapeutics, Inc.

Consolidated Statements of Operations

(unaudited, in thousands except share and per share data)

Galera Therapeutics, Inc.

Selected Consolidated Balance Sheet Data

(unaudited, in thousands)

Galera Therapeutics, Inc.