Agreement augments Fusion’s existing isotope supply as pipeline of clinical stage actinium-based radiopharmaceuticals grows 

Furthers BWXT Medical’s position as a global leader in medical isotope supply 

(Ottawa, ON) – January 5, 2023 – Fusion Pharmaceuticals Inc. (Nasdaq: FUSN), and BWXT Medical Ltd., a subsidiary of BWX Technologies, Inc. (NYSE: BWXT), today announced that the companies have entered into a preferred partner agreement for the supply of actinium-225. Under the agreement, BWXT Medical will provide predetermined amounts of Fusion’s actinium supply needs at volume-based pricing.

Actinium-225 is an alpha-emitting isotope used in targeted alpha therapies (TATs) that combine the isotope with specific tumor-seeking targeting vectors to kill cancer cells while minimizing the impact to healthy tissues. There is growing demand for the isotope but a limited number of suppliers who are currently able to produce meaningful quantities of high purity actinium. 

Fusion Chief Executive Officer John Valliant, Ph.D., said, "Fusion’s portfolio of clinical-stage targeted alpha therapies is expanding, with three proprietary programs in clinical trials and additional programs advancing under our collaboration with AstraZeneca. Based on emerging clinical data in the literature which show the power of alpha particles over conventional beta emitters, we continue to proactively prioritize access to actinium as a critical component of Fusion’s development plans and we are excited to partner with BWXT Medical. As an established global leader in medical isotope manufacturing and supply with proven ability to produce high purity actinium, BWXT Medical has the necessary infrastructure and shipping logistics capabilities to support both clinical and commercial scale manufacturing and distribution of medical isotopes. This agreement increases our existing actinium supply for both current programs as well as future business development opportunities and partnered programs, diversifies our supply chain, and establishes a relationship to collaborate on longer-term commercial production needs.” 

BWXT Medical President and Chief Executive Officer Jonathan Cirtain, Ph. D., said, "Excitement for the potential of targeted alpha therapies to treat cancer is growing, and we have made the necessary investments in infrastructure and intellectual property to help meet the increasing global demand for actinium. BWXT Medical is now producing high-purity non-carrier added actinium-225. Fusion is a leading developer of targeted alpha therapies, and we are pleased to work with them as their clinical programs continue to advance."

About Fusion
Fusion Pharmaceuticals is a clinical-stage oncology company focused on developing next-generation radiopharmaceuticals as precision medicines. Fusion connects alpha particle emitting isotopes to various targeting molecules in order to selectively deliver the alpha emitting payloads to tumors. Fusion's lead program, FPI-1434 targeting insulin-like growth factor 1 receptor, is currently in a Phase 1 clinical trial. The pipeline includes FPI-1966, targeting the fibroblast growth factor receptor 3 (FGFR3), advancing to a Phase 1 study following the investigational new drug (IND) clearance; and FPI-2059, a small molecule targeting neurotensin receptor 1 (NTSR1). In addition to a robust proprietary pipeline, Fusion has a collaboration with AstraZeneca to jointly develop novel targeted alpha therapies (TATs) and combination programs between Fusion's TATs and AstraZeneca's DNA Damage Repair Inhibitors (DDRis) and immuno-oncology agents. Fusion has also entered into a collaboration with Merck to evaluate FPI-1434 in combination with Merck's KEYTRUDA® (pembrolizumab) in patients with solid tumors expressing IGF-1R. Fusion and Hamilton, Ontario-based McMaster University are building a current Good Manufacturing Practice (GMP) compliant radiopharmaceutical manufacturing facility designed to support manufacturing of the Company's growing pipeline of TATs.

About BWXT Medical
BWXT Medical Ltd. manufactures custom radiopharmaceuticals, radiotherapies and medical isotopes in an 80,000-square-foot cGMP manufacturing facility in Ottawa and at the state-of-the-art commercial cyclotron facility within TRIUMF, Canada’s particle acceleration centre. BWXT Medical Ltd. is a subsidiary of BWX Technologies, Inc. (NYSE: BWXT). BWXT is a Fortune 1000 and Defense News Top 100 manufacturing and engineering innovator that provides safe and effective nuclear solutions for global security, clean energy, environmental remediation, nuclear medicine and space exploration. Follow us on Twitter at @BWXT and learn more at www.bwxt.com. 

Forward Looking Statements
BWX Technologies, Inc. (“BWXT”) cautions that this release contains forward-looking statements, including statements relating to expectations for the development, production, performance, demand, timing and impact of Ac-225. These forward-looking statements involve a number of risks and uncertainties, including, among other things, changes in market demand, delays in the development and automation of our production, regulatory approvals and potential supply chain issues. If one or more of these or other risks materialize, actual results may vary materially from those expressed. For a more complete discussion of these and other risk factors, please see BWXT’s annual report on Form 10-K for the year ended December 31, 2021 and subsequent quarterly reports on Form 10-Q filed with the Securities and Exchange Commission. BWXT cautions not to place undue reliance on these forward-looking statements, which speak only as of the date of this release, and undertakes no obligation to update or revise any forward-looking statement, except to the extent required by applicable law.

###

Media Contact
Jud Simmons
Director, Media & Public Relations
434.522.6462 hjsimmons@bwxt.com

Investor Contact
Mark Kratz                                                                            
Vice President, Investor Relations
980.365.4300 investors@bwxt.com