Description of Securities

Exhibit 4.1

DESCRIPTION OF SECURITIES

Our authorized capital stock consists of 75,000,000 shares of common stock, $0.01 par value per share (“Common Stock”), and 5,000,000 shares of preferred stock, $0.01 par value per share. A description of material terms and provisions of our amended and restated certificate of incorporation and bylaws affecting the rights of holders of our capital stock is set forth below. The description is intended as a summary, and is qualified in its entirety by reference to our amended and restated certificate of incorporation and the bylaws.

On December 18, 2015, we effected a 1-for-25 reverse stock split and 25 shares of our outstanding Common Stock decreased to one share of Common Stock. Similarly, the number of shares of Common Stock issuable upon the exercise of outstanding stock options or warrants, or upon the vesting of outstanding restricted stock units, decreased on a 1-for-25 basis and the exercise price of each outstanding option and warrant increased proportionately.

Common Stock

Dividend rights. Subject to preferences that may apply to shares of preferred stock outstanding at the time, the holders of outstanding shares of our Common Stock are entitled to receive dividends out of funds legally available if our Board of Directors (the “Board”), in its discretion, determines to issue dividends and then only at the times and in the amounts that our Board may determine.

Voting rights. Each holder of Common Stock is entitled to one vote for each share of Common Stock held on all matters submitted to a vote of stockholders. Our amended and restated certificate of incorporation does not provide for the right of stockholders to cumulate votes for the election of directors. Our amended and restated certificate of incorporation establishes a classified Board, divided into three classes with staggered three-year terms. Only one class of directors is elected at each annual meeting of our stockholders, with the other classes continuing for the remainder of their respective three-year terms.

No preemptive or similar rights. Our Common Stock is not entitled to preemptive rights and is not subject to conversion, redemption or sinking fund provisions. The rights, preferences and privileges of the holders of our Common Stock are subject to, and may be adversely affected by, the rights of the holders of any series of our preferred stock that we may designate and issue in the future.

Right to receive liquidation distributions. Upon our dissolution, liquidation or winding-up, the assets legally available for distribution to holders of our Common Stock are distributable ratably among the holders of our Common Stock, subject to prior satisfaction of all outstanding debt and liabilities and the preferential rights and payment of liquidation preferences, if any, on any outstanding shares of our preferred stock.

The rights of the holders of our Common Stock are subject to, and may be adversely affected by, the rights of holders of shares of any preferred stock that we may designate and issue in the future.

Anti-takeover effects of provisions of our certificate of incorporation and bylaws and Delaware law

Amended and restated certificate of incorporation and bylaws. Our amended and restated certificate of incorporation provides that our Board is divided into three classes with staggered three-year terms. Only one class of directors is elected at each annual meeting of our stockholders, with the other classes continuing for the remainder of their respective three-year terms. Because holders of our Common Stock do not have cumulative voting rights in the election of directors, stockholders holding a majority of the shares of Common Stock outstanding are able to elect all of our directors. Our Board is able to elect a director to fill a vacancy created by the expansion of the Board or due to the resignation or departure of an existing board member. Our amended and restated certificate of incorporation and bylaws also provide that all stockholder actions must be effected at a duly called meeting of stockholders and not by written consent, and that only the Board pursuant to a resolution adopted by a majority of the total number of authorized directors may call a special meeting of stockholders. In addition, our bylaws include a requirement for the advance notice of nominations for election to the Board or for proposing matters that can be acted upon at a stockholders’ meeting. Our amended and restated certificate of incorporation provides for the ability of the Board to issue, without stockholder approval, up to 5,000,000 shares of preferred stock with terms set by the Board, which rights could be senior to those of our Common Stock. Our amended and restated certificate of incorporation and bylaws also provide that approval of at least 66-2/3% of the shares entitled to vote at an election of directors will be required to adopt, amend or repeal our bylaws, or repeal the provisions of our amended and restated certificate of incorporation regarding the election of directors and the inability of stockholders to take action by written consent in lieu of a meeting.

The foregoing provisions make it difficult for holders of our Common Stock to replace our Board. In addition, the authorization of undesignated preferred stock makes it possible for our Board to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to change control of our Company.

Section 203 of the Delaware General Corporation Law

We are subject to the provisions of Section 203 of the Delaware General Corporation Law regulating corporate takeovers. This section prevents some Delaware corporations from engaging, under some circumstances, in a business combination, which includes a merger or sale of at least 10% of the corporation’s assets with any interested stockholder, meaning a stockholder who, together with affiliates and associates, owns or, within three years prior to the determination of interested stockholder status, did own 15% or more of the corporation’s outstanding voting stock, unless:

A Delaware corporation may “opt out” of these provisions with an express provision in its original certificate of incorporation or an express provision in its certificate of incorporation or bylaws resulting from a stockholders’ amendment approved by at least a majority of the outstanding voting shares. We do not plan to “opt out” of these provisions. The statute could prohibit or delay mergers or other takeover or change in control attempts and, accordingly, may discourage attempts to acquire us.

Transfer Agent and Registrar

Computershare Shareholder Services, Inc., located in Providence, Rhode Island, Providence County, is the transfer agent and registrar for our Common Stock in the United States and Computershare Investor Services, Inc., located in Toronto, Ontario, Canada, is the co-transfer agent and registrar for our Common Stock in Canada. The transfer agent for any series of preferred stock that we may offer under this prospectus will be named and described in the prospectus supplement related to that series.

Listing on the NYSE American

Our Common Stock is listed on the NYSE American under the symbol “NBY.” The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on the NYSE American or any securities market or other exchange of the preferred stock covered by such prospectus supplement.