According to the law firm press release, Prosensa Holding N.V. is a biotechnology company engaged in the discovery and development of RNA-modulating therapeutics for the treatment of genetic disorders. The Company’s first and lead product candidate was drisapersen, which Prosensa was developing in collaboration with GlaxoSmithKline to address a variety of mutations resulting in inadequate production of dystrophin ? a protein necessary for muscle function.

The Complaint alleges that the Registration Statement contained materially false and/or misleading statements and/or omitted material information concerning the development status of drisapersen, the drug’s Phase II and Phase III clinical studies, and the prospects for drisapersen’s regulatory approval.

On September 20, 2013, less than three months after the IPO, the Company issued a joint press release with GlaxoSmithKline, disclosing that drisapersen had not met the primary endpoint in the Phase III study. According to the press release, "[t]here was no treatment difference in key secondary assessments of motor function: 10-meter walk/run test, 4-stair climb and North Star Ambulatory Assessment."

As a result of this news, Prosensa stock declined approximately 70 percent, or $16.86 per share, on unusually heavy trading volume, to close on September 20, 2013 at $7.14 per share.

On October 9, 2014, the Court issued an Order appointing lead Plaintiff and approving lead Counsel.

On May 5, 2015, the Court issued an Order granting defendants' motion to dismiss. The Clerk was directed to close this case. On May 19, Plaintiffs filed a motion for reconsideration of the Court's May 5 Order. On June 25, the Court issued an Order denying Plaintiff's motion for reconsideration.

On June 3, 2015, Plaintiffs filed a Notice appealing the Court's May 5 decision. On June 30, Plaintiffs filed an amended Notice of appeal. Plaintiffs filed a stipulation withdrawing the appeal on August 8.