SUBSCRIPTION AGREEMENT

Exhibit 10.1

SUBSCRIPTION AGREEMENT

Cascadian Therapeutics, Inc.

2601 Fourth Avenue, Suite 500

Seattle, Washington 98121

Ladies and Gentlemen:

The undersigned (the “Investor”) hereby confirms and agrees with you as follows:

(a) The Company has the requisite corporate power and authority to enter into and to consummate the transactions contemplated by this Agreement and otherwise to carry out its obligations hereunder. The execution and delivery of this Agreement by the Company and the consummation by it of the transactions contemplated hereunder have been duly authorized by all necessary action on the part of the Company. This Agreement has been duly executed by the Company and, when delivered in accordance with the terms hereof, will constitute the valid and binding obligation of the Company enforceable against the Company in accordance with its terms, except as may be limited by any bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or other similar laws affecting the enforcement of creditors’ rights generally or by general principles of equity.

(b) The Company shall (i) before 9:30 A.M., New York City time, on June 23, 2016, issue a press release, disclosing all material aspects of the transactions contemplated hereby, (ii) on June 23, 2016, file with the Commission a Current Report on Form 8-K, disclosing the material terms and conditions of the transactions contemplated hereby and (ii) make such other filings and notices in the manner and time required by the Commission with respect to the transactions contemplated hereby.

(c) The Company shall not sell, offer for sale or solicit offers to buy any security (as defined in Section 2 of the Securities Act) in a transaction that would be (i) integrated with the offer or sale of the Shares for purposes of the rules and regulations of The NASDAQ Global Market and (ii) would require approval of the Company’s stockholders prior to the closing of such other transaction, unless such stockholder approval is obtained before the closing of such other transaction.

(d) If the Company applies to have the Common Stock traded on any trading market other than The NASDAQ Global Market, it will then include in such application all of the Shares, and will take such other action as is reasonably necessary to cause all of the Common Stock to be listed or quoted on such other trading market as promptly as possible.

(a) The Company’s obligation to issue and sell the Shares to the Investor shall be subject to: (i) the receipt by the Company of the purchase price for the Shares being purchased hereunder as set forth on the signature page hereto and (ii) the accuracy of the representations and warranties made by the Investor and the fulfillment of those undertakings of the Investor to be fulfilled prior to the Closing Date.

(b) The Investor’s obligation to purchase the Shares shall be subject to the accuracy of the representations and warranties made by the Company and the fulfillment of those undertakings of the Company to be fulfilled prior to the Closing Date, including without limitation, those contained in the Placement Agreement, and to the condition that the Placement Agents shall not have: (i) terminated the Placement Agreement pursuant to the terms thereof or (ii) determined that the conditions to closing in the Placement Agreement have not been satisfied. The Investor’s obligations are expressly not conditioned on the purchase by any or all of the other Investors of the Shares that they have agreed to purchase from the Company.

(a) The Investor represents that it has received or had full access to the Statutory Prospectus as well as the Company’s periodic reports and other information incorporated by reference therein, prior to or in connection with its receipt of this Agreement.

(b) The Investor has the requisite power and authority to enter into this Agreement and to consummate the transactions contemplated hereby. The execution and delivery of this Agreement by the Investor and the consummation by it of the transactions contemplated hereunder have been duly authorized by all necessary action on the part of the Investor. This Agreement has been executed by the Investor and, when delivered in accordance with the terms hereof, will constitute a valid and binding obligation of the Investor enforceable against the Investor in accordance with its terms.

(c) The Investor understands that nothing in this Agreement or any other materials presented to the Investor in connection with the purchase and sale of the Shares constitutes legal, tax or investment advice. The Investor has consulted such legal, tax and investment advisors as it, in its sole discretion, has deemed necessary or appropriate in connection with its purchase of Shares.

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(d) The making, execution and performance of this Agreement by the Investor and the consummation of the transactions contemplated herein will not conflict with or result in a breach or violation of any of the terms and provisions of, or constitute a default under, (i) the charter, bylaws or other organizational documents of such Investor, as applicable, or (ii) any law, order, rule, regulation, writ, injunction, judgment or decree of any court, administrative agency, regulatory body, government or governmental agency or body, domestic or foreign, having jurisdiction over such Investor or its properties, except for any conflict, breach, violation or default which is not reasonably likely to have a material adverse effect on such Investor’s performance of its obligations hereunder or the consummation of the transactions contemplated hereby.

(e) Neither the Investor nor any Person acting on behalf of, or pursuant to any understanding with or based upon any information received from, the Investor has, directly or indirectly, engaged in any Short Sales involving the Company’s securities since the date that is the tenth (10^th) trading day prior to the date of this Agreement. “Short Sales” include, without limitation, all “short sales” as defined in Rule 200 promulgated under Regulation SHO under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), whether or not against the box, and all types of direct and indirect stock pledges, forward sale contracts, options, puts, calls, short sales, swaps, “put equivalent positions” (as defined in Rule 16a- 1(h) under the Exchange Act) and similar arrangements (including on a total return basis), and sales and other transactions through non-U.S. broker dealers or foreign regulated brokers. The Investor covenants that neither it, nor any Person acting on behalf of, or pursuant to any understanding with or based upon any information received from, the Investor will engage in any transactions in the securities of the Company (including Short Sales) prior to the time that the transactions contemplated by this Agreement are publicly disclosed. Notwithstanding the foregoing, in the case of an Investor and/or its affiliates that is, individually or collectively, a multi-managed investment bank or vehicle whereby separate portfolio managers manage separate portions of such Investor’s or affiliates assets and the portfolio managers have no direct knowledge of the investment decisions made by the portfolio managers managing other portions of such Investor’s or affiliates assets, the representation set forth above shall only apply with respect to the portion of assets managed by the portfolio managers that have knowledge about the financing transaction contemplated by this Agreement.

(f) The Investor represents that, except as set forth below and except as set forth in any Information Statement filed under Section 13D of the Securities Exchange Act of 1934, (i) it has had no position, office or other material relationship within the past three years with the Company or persons known to it to be affiliates of the Company, (ii) it is not a member of the Financial Industry Regulatory Authority, Inc. (“FINRA”) or an Associated Person (as such term is defined under FINRA’s NASD Membership and Registration Rules Section 1011) as of the date hereof and (iii) neither it nor any group of investors (as identified in a public filing made with the Commission) of which it is a member, acquired or obtained the right to acquire 20% or more of the Common Stock (or securities convertible or exercisable for Common Stock) or voting power of the Company on a post-transaction basis.

(g) If the Investor is a retirement plan or is investing on behalf of a retirement plan, the Investor acknowledges that an investment in the Shares poses additional risks, including the inability to use losses generated by an investment in the Shares to offset taxable income.

(h) The Investor acknowledges that no action had been or will be taken in any jurisdiction outside the United States by the Company that would permit an offering of the Shares, or possession or distribution of offering materials in connection with the issue of the Shares, in any jurisdiction outside the United States where action for that purpose is required. Each Investor outside the United States will comply with all applicable laws and regulations in each foreign jurisdiction in which it purchases, offers, sells or delivers Shares or has in its possession or distributes any offering material, in all cases at its own expense.

(i) The Investor acknowledges that the Company and others will rely upon the truth and accuracy of the foregoing representations, acknowledgements and agreements and agrees that if any of the representations, warranties and acknowledgements deemed to have been made by it by its purchase of the Shares is no longer accurate, the Investor shall promptly notify the Company. If the Investor is acquiring Shares as a fiduciary or agent for one or more investor accounts, it represents that is has sole investment discretion with respect to each such account and it has full power to make the foregoing representations, warranties, acknowledgements and agreements on behalf of such account.

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Number of Shares:                 

Purchase Price Per Share: $         

Aggregate Purchase Price: $         

Please confirm that the foregoing correctly sets forth the agreement between us by signing in the space provided below for that purpose.

Dated as of: June     , 2016

Name in which Shares are to be registered:

Mailing Address:

Taxpayer Identification Number:

Agreed and Accepted this      day of             , 2016:

Sales of the Shares purchased hereunder were made pursuant to a registration statement or in a transaction in which a final prospectus would have been required to have been delivered in the absence of Rule 172 promulgated under the Securities Act.

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EXHIBIT A

TO BE COMPLETED BY INVESTOR

DWAC SETTLEMENT

Delivery by electronic book-entry at The Depository Trust Company (“DTC”), registered in the Investor’s name and address as set forth on the signature page of the Agreement to which this Exhibit A is attached, and released by Computershare Trust Company, N.A., the Company’s transfer agent (the “Transfer Agent”), to the Investor at the Closing.

NO LATER THAN ONE (1) BUSINESS DAY AFTER THE EXECUTION OF THE AGREEMENT TO WHICH THIS EXHIBIT A IS ATTACHED BY THE INVESTOR AND THE COMPANY, THE INVESTOR SHALL:

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