IMPORTANT SEATTLE GENETICS INC. INVESTOR REMINDER: Wolf Haldenstein Adler Freeman & Herz LLP reminds investors that a securities class action lawsuit has been filed in the Western District of Washington against Seattle Genetics Inc.

NEW YORK, Feb. 28, 2017 -- Wolf Haldenstein Adler Freeman & Herz LLP announces that a class action lawsuit has been filed against Seattle Genetics Inc. (“Seattle Genetics” or the “Company”) (NASDAQ:SGEN) and certain of its officers.  The class action, filed in United States District Court for the Western District of Washington is on behalf of a class consisting of all persons or entities who purchased or otherwise acquired Seattle Genetics securities between October 27, 2016 and December 23, 2016, inclusive (the “Class Period”).

Investors who have incurred losses in shares of Seattle Genetics Inc. are urged to contact the firm immediately at [email protected] or (800) 575-0735 or (212) 545-4774. You may obtain additional information concerning the action on our website, www.whafh.com.

If you have purchased shares of Seattle Genetics Inc. within the class period and would like to assist with the litigation process, you may, no later than March 13, 2017, request that the Court appoint you lead plaintiff of the proposed class.

Seattle Genetics develops and commercializes targeted therapies for the treatment of cancer worldwide.  Among the Company’s products in development is SGN-CD33A (vadastuximab talirine).  Throughout the Class Period,  vadastuximab talirine was  in  clinical  trials for  various  applications,  including,  in relevant part: (i) a Phase 1/2  trial in patients with acute myeloid leukemia (AML) as a pre-conditioning regimen prior to an allogenic stem cell transplant and as a maintenance therapy following transplant; (ii) a Phase 1 trial evaluating vadastuximab talirine monotherapy, including a subset of older  AML patients in combination with hypomethylating agents; and (iii) a Phase 1 trial evaluating vadastuximab talirine combination treatment with 7+3 chemotherapy in newly diagnosed younger AML patients.

The filed Complaint  alleges  that throughout the Class  Period, Defendants  made materially false and/or misleading statements,  as well as failed to  disclose  material  adverse  facts  about the  Company’s  business, operations, and prospects.  Specifically, Defendants made  false and/or misleading  statements and/or  failed  to  disclose  that: (i) vadastuximab  talirine presents  a significant risk of fatal hepatotoxicity;  (ii) as such, Seattle Genetics had overstated the viability of vadastuximab talirine as an  AML treatment;  and (iii) as a result of the foregoing, Seattle Genetics’ public statements  were materially false and misleading at all relevant times. 

On December 27,  2016, Seattle  Genetics issued a  press release  and filed  a Form  8-K with the  Securities and Exchange Commission (SEC) announcing that  the Food  and Drug Administration had (FDA) placed a clinical  hold or partial  clinical hold  on several  early  stage  trials  of  the  Company’s  experimental  cancer  drug,  vadastuximab talirine,  to evaluate the potential risk of hepatotoxicity.

On this news, Seattle Genetics’ share price fell $9.50, or 15.36 %, to close at $52.36 on December 27, 2016.

Wolf Haldenstein has extensive experience in the prosecution of securities class actions and derivative litigation in state and federal trial and appellate courts across the country.  The firm has attorneys in various practice areas; and offices in New York, Chicago and San Diego.  The reputation and expertise of this firm in shareholder and other class litigation has been repeatedly recognized by the courts, which have appointed it to major positions in complex securities multi-district and consolidated litigation.

If you wish to discuss this action or have any questions regarding your rights and interests in this case, please immediately contact Wolf Haldenstein by telephone at (800) 575-0735, via e-mail at [email protected], or visit our website at www.whafh.com.

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Contact:

Wolf Haldenstein Adler Freeman & Herz LLP 
Patrick Donovan, Esq.
Gregory Stone, Director of Case and Financial Analysis
Email: [email protected], [email protected] or [email protected]
Tel: (800) 575-0735 or (212) 545-4774