-

SHAREHOLDER ALERT: Robbins LLP Reminds Investors that Sesen Bio, Inc. (SESN) is Being Sued for Misleading Shareholders

SAN DIEGO--(BUSINESS WIRE)--Shareholder rights law firm Robbins LLP reminds investors that a shareholder filed a class action on behalf of all persons and entities that purchased or otherwise acquired Sesen Bio, Inc. (NASDAQ: SESN) securities between December 21, 2020 and August 17, 2021, for violations of the Securities Exchange Act of 1934. Sesen Bio is a late-stage clinical company. Its most advanced product candidate is Vicineum, a treatment for bacillus Calmette-Guérin ("BCG")-unresponsive non-muscle invasive bladder cancer ("NMIBC").

If you suffered a loss due to Sesen Bio, Inc.'s misconduct, click here.

Sesen Bio, Inc. (SESN) Hid Information Relating to the Failure of its Clinical Trials for Vicineum

According to the complaint, on December 21, 2020, Sesen Bio announced it had submitted its Biologics License Application ("BLA") to the FDA for Vicineum for the treatment of BCG-unresponsive NMIBC.

During the relevant period, defendants expressed its "significant commercial progress" and ramped up operations in anticipation that Vicineum would be granted FDA approval. However, defendants failed to disclose to investors that: (1) Sesen Bio’s clinical trial for Vicineum had more than 2,000 violations of trial protocol; (2) three of Sesen Bio’s clinical investigators were found guilty of “serious noncompliance,” including “back-dating data”; (3) Sesen Bio had submitted the tainted data in connection with the BLA for Vicineum; (4) Sesen Bio’s clinical trials showed that Vicineum leaked out into the body, leading to side effects including liver failure and liver toxicity, and increasing the risks for fatal, drug-induced liver injury; (5) as a result of the foregoing, the Company’s BLA for Vicineum was not likely to be approved; and (6) consequently, there was a reasonable likelihood that Sesen Bio would be required to conduct additional trials to support the efficacy and safety of Vicineum.

On August 13, 2021, the Company announced that the FDA declined to approve its BLA for Vicineum in its current form. On this news, the Company's share price fell $2.80, or 57%, to close at $2.11 per share on August 13, 2021.

On August 16, 2021, the Company further revealed that "it appears that [the Company] will need to do a clinical trial to provide the additional efficacy and safety data necessary for the FDA to assess the benefit-risk profile, which is the basis for approval." As a result, the Company expected that it could not resubmit its BLA until 2023. On this news, the stock fell $0.89, or 42%, to close at $1.22 per share on August 16, 2021.

Then, on August 18, 2021, the health and medicine news site STAT published an article detailing that the clinical trial for Vicineum was "marked by thousands of violations of study rules, damning investigator conduct, and worrying signs of toxicity the company did not publicly disclose." On this news, the Company's share price fell another 13%, to close at $1.31 per share on August 18, 2021.

If you purchased shares of Sesen Bio, Inc. (SESN) securities between December 21, 2020 and August 17, 2021, you have until October 18, 2021, to ask the court to appoint you lead plaintiff for the class.

All representation is on a contingency fee basis. Shareholders pay no fees or expenses.

Contact us to learn more:

Aaron Dumas
(800) 350-6003
adumas@robbinsllp.com
Shareholder Information Form

Robbins LLP is a nationally recognized leader in shareholder rights law. To be notified if a class action against Sesen Bio, Inc. settles or to receive free alerts when corporate executives engage in wrongdoing, sign up for Stock Watch today.

Attorney Advertising. Past results do not guarantee a similar outcome.

Contacts

Aaron Dumas
Robbins LLP
5040 Shoreham Place
San Diego, CA 92122
adumas@robbinsllp.com
(800) 350-6003
www.robbinsllp.com

More News From Robbins LLP

Investor Notice: Robbins LLP Informs Investors of the Klarna Group plc Securities Class Action

SAN DIEGO--(BUSINESS WIRE)--Robbins LLP informs stockholders that a class action was filed on behalf of all investors who purchased or otherwise acquired Klarna Group plc (NASDAQ: KLAR) securities pursuant and/or traceable to the registration statement and related prospectus issued in connection with Klarna's September 10, 2025, initial public offering ("IPO"). Klarna purports to be a “technology-driven payments company, with operations spanning multiple countries.” For more information, submit...

CPNG Class Action Notice: Robbins LLP Reminds Investors of the Lead Plaintiff Deadline in the Class Action Against Coupang, Inc.

SAN DIEGO--(BUSINESS WIRE)--Robbins LLP reminds stockholders that a class action was filed on behalf of all investors who purchased or otherwise acquired Coupang, Inc. (NYSE: CPNG) securities between April 6, 2025 and December 16, 2025. Coupang describes itself as one of the fastest-growing technology and commerce companies in the world, providing retail, restaurant delivery, video streaming, and fintech services to customers around the world under brands that include Coupang, Coupang Eats, Cou...

Did You Lose Money in SFM? Stockholders Who Incurred Significant Financial Loss in Sprouts Farmers Market, Inc. Should Contact Robbins LLP to Learn About Leading the SFM Class Action Lawsuit

SAN DIEGO--(BUSINESS WIRE)--Robbins LLP: Company: Sprouts Farmers Market, Inc. (NASDAQ: SFM) is a specialty grocery store chain that operates in the U.S. What is the class period? June 4, 2025 - October 29, 2025. What is the case about? Robbins LLP reminds stockholders that a class action was filed on behalf of all investors who purchased or otherwise acquired Sprouts Farmers Market, Inc. during the class period because the Company allegedly misled investors regarding its growth potential. For...
Back to Newsroom