Citi, acting through Citibank N.A., has been appointed by Nightstar Therapeutics plc (“Nightstar”) as depositary bank for its American Depositary Receipt (“ADR”) programme. Nightstar’s American Depositary Shares trade on the NASDAQ Global Select Market under the symbol “NITE.” Each ADS represents one ordinary share of Nightstar.

“Citi is delighted to be appointed by Nightstar as depositary bank for its NASDAQ listed ADR programme,” said Dirk Jones, Global Head of Issuer Services, at Citi. “We are confident that we will be able to assist Nightstar in expanding their investor outreach through the support of our Investor Relations Advisory team and our unparalleled equity distribution network.”

For more information on Citi’s Depositary Receipt Services, visit www.citi.com/dr.

About Nightstar

Nightstar is a leading clinical-stage gene therapy company focused on developing and commercializing novel one-time treatments for patients suffering from rare inherited retinal diseases, including choroideremia, X-linked retinitis pigmentosa and Best vitelliform macular dystrophy.

About Citi

Citi, the leading global bank, has approximately 200 million customer accounts and does business in more than 160 countries and jurisdictions. Citi provides consumers, corporations, governments and institutions with a broad range of financial products and services, including consumer banking and credit, corporate and investment banking, securities brokerage, transaction services, and wealth management.

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