EGT Wins Major Victory in New York Court

EGT Wins Major Victory in New York Court

New York Court Sanctions Bluebird Bio, Paving Way for EGT to
Proceed with Lawsuit in Massachusetts for Substantial Damages
Against Bluebird CEO Nick Leschly and Third Rock Ventures

Chicago, IL – On August 19, 2019, New York Supreme Court Justice Barry Ostrager sanctioned Bluebird
Bio, Inc. (“Bluebird”) and rejected Bluebird’s efforts to prevent Errant Gene Therapeutics (“EGT”) from
proceeding with its lawsuit in Massachusetts against Bluebird CEO Nick Leschly and Bluebird’s venture
capital partner, Third Rock Ventures, LLC (“TRV”). Following the court’s decision, EGT served its complaint
in Massachusetts yesterday, August 20, 2019, against Leschly and TRV.

EGT has been embroiled in a longstanding lawsuit in New York involving claims by EGT against Bluebird
and Sloan-Kettering Institute for Cancer Research (“SKI”). EGT alleges that SKI, in cooperation with
Bluebird, intentionally abandoned EGT’s potentially life-saving gene therapy solely for Bluebird’s benefit.

On June 7, 2019, EGT filed a complaint in Massachusetts against Leschly and TRV, alleging that they
embarked upon an unlawful scheme to prevent EGT from bringing its gene therapy to market. EGT alleges
that Leschly and TRV’s unfair and deceptive acts follow a troubling pattern of tortious business practices
undertaken by pharmaceutical companies to secretly and systematically “kill” competing medical
treatments.

In an effort to prevent the lawsuit from moving forward in Massachusetts, Bluebird sought to have the
New York court hold EGT in contempt in connection with EGT’s filing of the Massachusetts complaint. The
court denied Bluebird’s request, and also assessed monetary sanctions in the amount of $25,000 against
Bluebird for its meritless accusations against EGT.

Mr. Girondi stated that “EGT is very pleased by the New York court’s rulings on Monday. EGT believes
that it has suffered in excess of a billion dollars in damages as a result of Leschly’s and TRV’s actions, and
intends to vigorously pursue its claims and hold Leschly and TRV fully accountable.”

Monday’s decision comes on the heels of several recent rulings in favor of EGT, including the denial of
Bluebird and SKI’s motion for summary judgment, a ruling that EGT’s damages claim is “not speculative as
a matter of law,” and a ruling that EGT may proceed with its fraud claims against Bluebird based on
allegations that Bluebird attended secret meetings with SKI in effort to “surreptitiously” obtain EGT’s drug
therapy after EGT refused to sell it to Bluebird.

About Errant Gene Therapeutics, LLC

EGT is a privately held biopharmaceutical company established in 2003. For more information about EGT
and its programs, please visit www.errantgene.com.

Media:

media@errantgene.com

(312) 441-1800 x11

FOR IMMEDIATE RELEASE

August 22, 2019