# EDGAR Filing Document

**Accession Number:** 0001597264
**File Stem:** 0001104659-23-023064
**Filing Date:** 2023-2
**Character Count:** 168611
**Document Hash:** 2fa1c8b1c8a822a303d976f1fdcdce9f
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-23-023064.hdr.sgml**: 20230217

**ACCESSION NUMBER**: 0001104659-23-023064

**CONFORMED SUBMISSION TYPE**: 424B5

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20230217

**DATE AS OF CHANGE**: 20230217

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Blueprint Medicines Corp
- **CENTRAL INDEX KEY:** 0001597264
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 424B5
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-269843
- **FILM NUMBER:** 23640335

**BUSINESS ADDRESS:**
- **STREET 1:** 45 SIDNEY STREET
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139
- **BUSINESS PHONE:** 617-374-7580

**MAIL ADDRESS:**
- **STREET 1:** 45 SIDNEY STREET
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139

[**TABLE OF CONTENTS**](#TOC)

#### Filed Pursuant to Rule 424(b)(5)

#### Registration Statement No.: 333-269843

#### PROSPECTUS SUPPLEMENT to the Prospectus dated February 17, 2023
![[MISSING IMAGE: lg_blueprint-4c.jpg]](lg_blueprint-4c.jpg)

### UP TO $300,000,000

### COMMON STOCK
We have entered into a Sales Agreement with Cowen and Company, LLC, or Cowen, relating to shares of our common stock, par value $0.001 per share, offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, we may offer and sell shares of our common stock having an aggregate offering price of up to $300,000,000 from time to time through Cowen, acting as sales agent or principal.

Our common stock is listed on the Nasdaq Global Select Market under the symbol "BPMC". The last reported sales price of our common stock on the Nasdaq Global Select Market on February 15, 2023 was $44.03 per share.

 **Investing in our common stock involves a high degree of risk. See "Risk Factors" beginning on page [S-9](#sRIFA) of this prospectus supplement, as well as in the documents incorporated or deemed to be incorporated by reference into this prospectus supplement and the accompanying prospectus, for a discussion of the factors you should carefully consider before deciding to purchase our common stock.** 

Sales of our common stock, if any, under this prospectus supplement and the accompanying prospectus may be made in sales deemed to be an "at the market offering" as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended, or the Securities Act. Cowen is not required to sell any specific number or dollar amount of securities, but will act as a sales agent using commercially reasonable efforts consistent with its normal trading and sales practices, on mutually agreed terms between Cowen and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

Under the sales agreement, we may also sell shares of common stock to Cowen as principal for its own account, at a price to be agreed upon at the time of sale. If we sell shares to a Cowen as principal, we will enter into a separate terms agreement with Cowen, and we will describe the agreement in a separate prospectus supplement or pricing supplement.

The compensation to Cowen for sales of common stock sold pursuant to the Sales Agreement will be up to 3.0% of the gross proceeds of any shares of common stock sold under the Sales Agreement. In connection with the sale of the common stock on our behalf, Cowen will be deemed to be an "underwriter" within the meaning of the Securities Act, and the compensation to Cowen will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to Cowen with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended, or the Exchange Act. See section titled "Plan of Distribution" on page [S-15](#sPOD) of this prospectus supplement.

 **Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.** 

### COWEN
The date of this prospectus supplement is February 17, 2023.

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#### **TABLE OF CONTENTS**

---

| | |
|:---|:---|
| | **Page**  |
| [ABOUT THIS PROSPECTUS SUPPLEMENT](#sATPS)  | [S-1](#sATPS) |
| [WHERE YOU CAN FIND MORE INFORMATION](#sWYCF)  | [S-2](#sWYCF) |
| [INCORPORATION OF CERTAIN INFORMATION BY REFERENCE](#sIOCI)  | [S-2](#sIOCI) |
| [CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS](#sCSRF)  | [S-4](#sCSRF) |
| [PROSPECTUS SUPPLEMENT SUMMARY](#sPSS)  | [S-6](#sPSS) |
| [THE OFFERING](#sTHOF)  | [S-7](#sTHOF) |
| [RISK FACTORS](#sRIFA)  | [S-9](#sRIFA) |
| [USE OF PROCEEDS](#sUOP)  | [S-12](#sUOP) |
| [DILUTION](#sDIL)  | [S-13](#sDIL) |
| [PLAN OF DISTRIBUTION](#sPOD)  | [S-15](#sPOD) |
| [LEGAL MATTERS](#sLEMA)  | [S-16](#sLEMA) |
| [EXPERTS](#sEXP)  | [S-16](#sEXP) |

---

---

| | |
|:---|:---|
| [ABOUT THIS PROSPECTUS](#tATP)  | [1](#tATP) |
| [RISK FACTORS](#tRIFA)  | [2](#tRIFA) |
| [WHERE YOU CAN FIND MORE INFORMATION](#tWYCF)  | [3](#tWYCF) |
| [INCORPORATION BY REFERENCE](#tIBR)  | [4](#tIBR) |
| [CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS](#tCSRF)  | [5](#tCSRF) |
| [BLUEPRINT MEDICINES CORPORATION](#tBMC)  | [7](#tBMC) |
| [USE OF PROCEEDS](#tUOP)  | [8](#tUOP) |
| [DILUTION](#tDIL)  | [9](#tDIL) |
| [DESCRIPTION OF CAPITAL STOCK](#tDOCS)  | [10](#tDOCS) |
| [DESCRIPTION OF DEBT SECURITIES](#tDODS)  | [17](#tDODS) |
| [DESCRIPTION OF PURCHASE CONTRACTS AND PURCHASE UNITS](#tDOPC)  | [24](#tDOPC) |
| [DESCRIPTION OF WARRANTS](#tDOW)  | [25](#tDOW) |
| [PLAN OF DISTRIBUTION](#tPOD)  | [26](#tPOD) |
| [LEGAL MATTERS](#tLEMA)  | [29](#tLEMA) |
| [EXPERTS](#tEXP)  | [29](#tEXP) |

---

 **We are responsible for the information contained and incorporated by reference in this prospectus supplement, in any accompanying prospectus, and in any related free writing prospectus we prepare or authorize. We have not authorized anyone to give you any other information, and we take no responsibility for any other information that others may give you. If you are in a jurisdiction where offers to sell, or solicitations of offers to purchase, the securities offered by this documentation are unlawful, or if you are a person to whom it is unlawful to direct these types of activities, then the offer presented in this document does not extend to you. The information contained in this document speaks only as of the date of this document, unless the information specifically indicates that another date applies. Our business, financial condition, results of operations and prospects may have changed since those dates.** 

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#### EXPLANATORY NOTE
This prospectus supplement covers the offering, issuance and sale by the registrant of up to a maximum aggregate offering price of $300,000,000 of the registrant's common stock that may be issued and sold from time to time under a sales agreement with Cowen and Company, LLC, or the Sales Agreement. On February 13, 2020, the registrant filed a shelf registration statement on Form S-3ASR which became automatically effective upon filing, or the Prior Registration Statement. On February 17, 2022, the registrant filed a sales agreement prospectus supplement to such shelf registration statement, or the Existing Sales Agreement Prospectus, with respect to the Sales Agreement. The Prior Registration Statement expired on February 13, 2023, and pursuant to Section 7(y) of the Sales Agreement, we are filing this prospectus supplement to our registration statement on Form S-3ASR, filed on February 17, 2023. No terms of the Sales Agreement, including the number of shares reserved, have changed.

As of immediately prior to the filing of this prospectus supplement, all of the registrant's common stock remained available for sale under the Existing Sales Agreement Prospectus. Effective upon the filing of this prospectus supplement, no further sales of common stock pursuant to the Sales Agreement will be made under the Existing Sales Agreement Prospectus.

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#### ABOUT THIS PROSPECTUS SUPPLEMENT
This prospectus supplement is part of an automatic shelf registration statement that we filed on Form S-3ASR with the Securities and Exchange Commission, or SEC, as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act, using a "shelf" registration process. Under this shelf registration process, we may, from time to time, sell any combination of the securities described in the above-referenced registration statement. This prospectus supplement, together with the accompanying prospectus and the documents incorporated by reference therein and herein, includes all material information relating to this offering.

This prospectus supplement relates to the offering of our common stock. Before buying any of the common stock that we are offering, we urge you to carefully read this prospectus supplement and the accompanying prospectus, together with the information incorporated by reference as described under the headings "Where You Can Find More Information" and "Incorporation of Certain Information by Reference" in this prospectus supplement, and any accompanying prospectus or free writing prospectus that we have authorized for use in connection with this offering. These documents contain important information that you should consider when making your investment decision. This Sales Agreement prospectus is deemed a prospectus supplement to the base prospectus contained in the registration statement of which this Sales Agreement prospectus forms a part.

This prospectus supplement describes the terms of this offering of common stock and also adds to and updates information contained in the documents incorporated by reference into the accompanying prospectus. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in any document incorporated by reference into this prospectus supplement and the accompanying prospectus, on the other hand, you should rely on the information in this prospectus supplement. If any statement in one of these documents is inconsistent with a statement in another document having a later date — for example, a document incorporated by reference into this prospectus supplement — the statement in the document having the later date modifies or supersedes the earlier statement.

We have not, and Cowen has not, authorized anyone to provide you with information in addition to or different from that contained in this prospectus supplement, the accompanying prospectus and any related free writing prospectus. We and Cowen take no responsibility for, and can provide no assurances as to the reliability of, any information not contained in this prospectus supplement, the accompanying prospectus or any related free writing prospectus that we may authorize to be provided to you. This prospectus supplement is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. You should assume that the information in this prospectus supplement, the accompanying prospectus or any related free writing prospectus is accurate only as of the date on the front of the document and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus supplement, the accompanying prospectus or any related free writing prospectus, or any sale of a security.

We are offering to sell, and seeking offers to buy, shares of common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

This prospectus supplement contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus supplement and the accompanying prospectus are a part, and you may obtain copies of those documents as described below under the heading "Where You Can Find More Information".

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 *Unless otherwise stated, all references in this prospectus supplement or the accompanying prospectus to "us", "our", "Blueprint", "Blueprint Medicines", "we", the "Company" and similar designations refer, collectively, to Blueprint Medicines Corporation, a Delaware corporation, and its consolidated subsidiaries.* 

#### WHERE YOU CAN FIND MORE INFORMATION
We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at www.blueprintmedicines.com. Our website is not a part of this prospectus supplement and is not incorporated by reference in this prospectus supplement.

This prospectus supplement is part of a registration statement we filed with the SEC. This prospectus supplement omits some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information on us and our consolidated subsidiary and the securities we are offering. Statements in this prospectus supplement concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings. You should review the complete document to evaluate these statements. You can obtain a copy of the registration statement from the SEC at the address listed above or from the SEC's website.

#### INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus supplement is considered to be part of this prospectus supplement. Because we are incorporating by reference future filings with the SEC, this prospectus supplement is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus supplement. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus supplement or in any document previously incorporated by reference have been modified or superseded. This prospectus supplement incorporates by reference the documents listed below (File No. 001-37359) and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed) until the offering of the securities under the registration statement is terminated or completed:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [Annual Report on Form 10-K for the fiscal year ended December 31, 2022, which was filed with the SEC on February 16, 2023;](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • The information specifically incorporated by reference into our [Annual Report on Form 10-K for the fiscal year ended December 31, 2021](http://www.sec.gov/Archives/edgar/data/1597264/000155837022001316/bpmc-20211231x10k.htm) from our [definitive proxy statement](http://www.sec.gov/Archives/edgar/data/1597264/000155837022006381/tmb-20220621xdef14a.htm) [(other than information furnished rather than filed) for the 2022 Annual Meeting of Stockholders, which was filed with the SEC on April 29, 2022;](http://www.sec.gov/Archives/edgar/data/1597264/000155837022006381/tmb-20220621xdef14a.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Current Reports on Form 8-K which were filed with the SEC on [January 6, 2023](http://www.sec.gov/Archives/edgar/data/1597264/000110465923001876/tm232336d1_8k.htm) and [February 10, 2023](http://www.sec.gov/Archives/edgar/data/1597264/000110465923017984/tm236270d1_8k.htm); and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [The description of our common stock contained in our Registration Statement on Form 8-A which were filed with the SEC on April 27, 2015, including any amendments or reports filed for the purpose of updating such description.](http://www.sec.gov/Archives/edgar/data/1597264/000110465915030565/a15-4342_98a12b.htm)

Notwithstanding the foregoing, unless specifically stated to the contrary, information that we furnish (and that is not deemed "filed" with the SEC) under Items 2.02 and 7.01 of any Current Report on Form 8-K, including the related exhibits under Item 9.01, is not incorporated by reference into this prospectus supplement or the registration statement of which this prospectus supplement is a part.

Any statement contained in a document that is incorporated by reference will be modified or superseded for all purposes to the extent that a statement contained in this prospectus supplement, or in any other document that is subsequently filed with the SEC and incorporated by reference into this prospectus

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supplement, modifies or is contrary to that previous statement. Any statement so modified or superseded will not be deemed a part of this prospectus supplement, except as so modified or superseded. Since information that we later file with the SEC will update and supersede previously incorporated information, you should look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus supplement or in any documents previously incorporated by reference have been modified or superseded.

You may request a copy of these filings, at no cost, by contacting us, either orally or in writing, at the following:

Blueprint Medicines Corporation

45 Sidney Street

Cambridge, Massachusetts 02139

Attn: Investor Relations

Phone: (617) 714-6674

E-mail: ir@blueprintmedicines.com

You may also access these documents, free of charge on the SEC's website at www.sec.gov or on our website at www.blueprintmedicines.com. Information contained on our website is not incorporated by reference into this prospectus supplement and you should not consider any information on, or that can be accessed from, our website as part of this prospectus supplement.

This prospectus supplement is part of a registration statement we filed with the SEC. We have incorporated exhibits into this registration statement. You should read the exhibits carefully for provisions that may be important to you.

You should rely only on the information incorporated by reference or provided in this prospectus supplement. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus supplement or in the documents incorporated by reference is accurate as of any date other than the date on the front of this prospectus supplement or those documents.

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#### CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
This prospectus supplement, the accompanying prospectus and the information incorporated by reference herein and therein contain statements that are not historical facts and are considered forward-looking within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. All statements, other than statements of historical facts, contained or incorporated by reference in this prospectus supplement are forward-looking statements. In some cases, you can identify forward-looking statements by words such as "anticipate", "believe", "contemplate", "continue", "could", "estimate", "expect", "intend", "may", "plan", "potential", "predict", "project", "seek", "should", "target", "will", "would" or the negative of these words or other comparable terminology, although not all forward-looking statements contain these identifying words. Forward-looking statements include, but are not limited to, statements about:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our expectations related to the use of any net proceeds from this offering;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the timing or likelihood of regulatory actions, filings and approvals for our current and future drug candidates, including our ability to obtain marketing approval for avapritinib and pralsetinib for additional indications or in additional geographies;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our ability and plans in continuing to build out our commercial infrastructure and successfully launching, marketing and selling AYVAKIT (avapritinib) (marketed in Europe under the brand name AYVAKYT), GAVRETO (pralsetinib) and any current and future drug candidates for which we receive marketing approval;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our expectations regarding the potential benefits of AYVAKIT/AYVAKYT and any current and future drug candidates in treating patients with indolent SM and advanced SM;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the rate and degree of market acceptance of AYVAKIT/AYVAKYT and any current and future drug candidates for which we receive marketing approval;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the pricing and reimbursement of AYVAKIT/AYVAKYT and any current and future drug candidates for which we receive marketing approval;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the initiation, timing, progress and results of our preclinical studies and clinical trials, including our ongoing clinical trials and any planned clinical trials for our current and future drug candidates and research and development programs;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our ability to advance drug candidates into, and successfully complete, clinical trials;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our ability to successfully develop manufacturing processes for any of our current and future drugs or drug candidates and to secure manufacturing, packaging and labeling arrangements for development activities and commercial production;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the implementation of our business model and strategic plans for our business, drugs, drug candidates, platform and technology;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the scope and length of protection we are able to establish and maintain for intellectual property rights covering our current and future drugs, drug candidates and technology;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the potential benefits of our collaboration with F. Hoffmann-La Roche Ltd and Genentech, Inc. to develop and commercialize pralsetinib globally (excluding Greater China), our cancer immunotherapy collaboration with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc., our collaboration with CStone Pharmaceuticals to develop and commercialize avapritinib, pralsetinib and fisogatinib in Greater China, our collaboration with Zai Lab to develop and commercialize BLU-525 and BLU-945, and any respective back-up forms and certain other forms thereof, as inhibitors of epidermal growth factor receptor (EGFR) in Greater China, our collaboration with Oncopia Therapeutics, Inc. d/b/a Proteovant Therapeutics, Inc. (Proteovant), to research and advance novel targeted protein degrader therapies to address medical needs in oncology and hematology, as well as our ability to maintain these collaborations and establish additional strategic collaborations;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the potential benefits of our exclusive license agreement with Clementia Pharmaceuticals, Inc., a wholly-owned subsidiary of Ipsen S.A. (Clementia) to develop and commercialize BLU-782 for fibrodysplasia ossificans progressiva;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the potential benefits of our strategic financing transactions with Garnich Adjacent Investments S.a.r.l. (Sixth Street Partners) and Royalty Pharma Investments 2019 ICAV (Royalty Pharma) and the potential acceleration of our commercial products and pipeline resulting from the non-dilutive growth capital;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the potential benefits of our license agreement with IDRx, Inc. (IDRx) to develop our development-stage KIT exon 13 inhibitor, IDRX-73, for the treatment of drug-resistant mutations of non-PDGFR-driven gastrointestinal stromal tumo (GIST);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the development of companion diagnostic tests for our current or future drugs or drug candidates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our financial performance, estimates of our revenues, expenses and capital requirements and our needs for future financing, including our ability to achieve a self-sustainable financial profile;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • developments relating to our competitors and our industry;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the actual or potential benefits of designations granted by the U.S. Food and Drug Administration (FDA), such as orphan drug, fast track and breakthrough therapy designation or priority review; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the impact and scope of the ongoing COVID-19 pandemic on our business, operations, strategy, goals and anticipated milestones, including our ongoing and planned research and discovery activities, ability to conduct ongoing and planned clinical trials, clinical supply of our current or future drug candidates or third-party products intended for use as combination therapies or as comparator agents, and the launch, marketing, sale and commercial supply of AYVAKIT/AYVAKYT, GAVRETO and any current or future drug candidates for which we receive marketing approval.

We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. We have included important factors in the cautionary statements included in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, particularly in the "Risk Factors" section beginning on page [S-9](#sRIFA) of this prospectus supplement and on page 53 of our [Annual Report on Form 10-K for the fiscal year ended December 31, 2022, as filed with the SEC on February 16, 2023](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm), that could cause actual results or events to differ materially from the forward-looking statements that we make. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures or investments we may make or enter into.

You should read this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, as well as the documents that we have filed as exhibits to the registration statement of which this prospectus supplement forms a part, completely and with the understanding that our actual future results, performance or achievements may be materially different from what we expect. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future.

This prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein also contain estimates, projections and other information concerning our industry, our business and the markets for certain diseases, including data regarding the estimated size of those markets, and the incidence and prevalence of certain medical conditions. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, studies and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources.

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#### PROSPECTUS SUPPLEMENT SUMMARY
 *This summary highlights certain information about us, this offering and selected information contained elsewhere in or incorporated by reference into this prospectus supplement. This summary is not complete and does not contain all of the information that you should consider before deciding whether to invest in our common stock. For a more complete understanding of our company and this offering, we encourage you to read and consider carefully the more detailed information in this prospectus supplement, including the information incorporated by reference in this prospectus supplement, and the information included in the accompanying prospectus or any free writing prospectus that we have authorized for use in connection with this offering, including the information under the heading "Risk Factors" in this prospectus supplement on page [S-9](#sRIFA) and in the documents incorporated by reference into this prospectus supplement.* 

#### Overview
We are a global precision therapy company that is inventing life-changing medicines for people with cancer and blood disorders. Applying an approach that is both precise and agile, we create therapies that selectively target genetic drivers, with the goal of staying one step ahead across stages of disease. Since 2011, we have leveraged our research platform, including expertise in molecular targeting and world-class drug design capabilities, to rapidly and reproducibly translate science into a broad pipeline of precision therapies. Today, we are delivering our approved medicines, AYVAKIT®/AYVAKYT® (avapritinib) and GAVRETO® (pralsetinib), to patients in the U.S. and Europe, and we are globally advancing multiple programs for systemic mastocytosis, or SM, lung cancer, breast cancer and other genomically defined cancers, and cancer immunotherapy.

Our drug discovery approach combines our biological insights with our proprietary compound library and chemistry expertise to design highly selective and potent precision therapies. We aim to enable potent target inhibition that provides significant and durable clinical responses, limit side effects driven by off-target activity and combine therapies to shut down disease drivers and resistance, with the goal of delivering significant and durable clinical benefit to patients based on the genetic driver of their disease. This uniquely targeted, scalable approach is designed to empower the rapid design and development of new treatments and increase the likelihood of success. In addition, our business model integrates our research engine with robust clinical development and commercial capabilities in oncology and hematology to create a cycle of innovation.

#### Our Strategy
Our vision is to leverage our scientific platform to design innovative first-in-class or best-in-class medicines targeting novel kinase biology and become a leading platform-enabled, fully-integrated, global precision therapy company focused on discovering, developing and commercializing a portfolio of precision therapies to patients with cancer and rare diseases.

#### Company Information
We were incorporated in Delaware in October 2008. Our mailing address and executive offices are located at 45 Sidney Street, Cambridge, Massachusetts 02139, and our telephone number is (617) 374-7580. We maintain an Internet website at the following address: www.blueprintmedicines.com. The information on, or that can be accessed through, our website does not constitute part of this prospectus supplement or the accompanying prospectus, and you should not rely on any such information in making the decision whether to purchase our common stock. Our common stock trades on the Nasdaq Global Select Market under the symbol "BPMC".

The trademarks, trade names and services marks appearing in this prospectus supplement and the accompanying prospectus are the property of their respective owners. Solely for convenience, the trademarks and trade names in this prospectus supplement may be referred to without the® and™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto.

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#### THE OFFERING
Common stock offered by us

Shares of our common stock having an aggregate offering price of up to $300.0 million

Common stock to be outstanding following this offering

Up to 66,772,455 shares (as more fully described in the notes following this table), assuming sales of 6,813,536 shares of our common stock in this offering at an offering price of $44.03 per share, which was the last reported sale price of our common stock on the Nasdaq Global Select Market on February 15, 2023. The actual number of shares issued will vary depending on the sales price under this offering.

Manner of offering

"At the market offering" that may be made from time to time on the Nasdaq Global Select Market or other existing trading market for our common stock through our sales agent, Cowen. See "Plan of Distribution" on page [S-15](#sPOD) of this prospectus supplement.

Use of proceeds

We intend to use the net proceeds from the sale of securities offered under this prospectus supplement primarily for general corporate purposes, which may include working capital and capital expenditures, expenses related to research, clinical development and commercial efforts, general and administrative expenses, and potential acquisitions of, or investments in, companies, technologies, products or assets that complement our business. See "Use of Proceeds" on page [S-12](#sUOP) of this prospectus supplement for additional information.

Risk factors

Investing in our common stock involves risks. See "Risk Factors" beginning on page [S-9](#sRIFA) of this prospectus supplement and other information included or incorporated by reference into this prospectus supplement and the accompanying prospectus for a discussion of the factors you should carefully consider before deciding to invest in our securities.

Nasdaq Global Select Market symbol

"BPMC"

The number of shares of common stock shown above to be outstanding after this offering is based on 59,958,919 shares outstanding as of December 31, 2022, and excludes as of that date:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 6,233,451 shares of common stock issuable upon the exercise of stock options outstanding as of December 31, 2022, at a weighted average exercise price of $69.14 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 1,893,994 shares of common stock issuable upon the vesting and settlement of restricted stock units outstanding as of December 31, 2022;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 4,116,893 shares of common stock reserved for future issuance under our 2015 Stock Option and Incentive Plan, or the 2015 Plan, as of December 31, 2022, plus any future increases in the number of shares of common stock reserved for issuance under the 2015 Plan pursuant to the evergreen provision of the 2015 Plan;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 1,473,235 shares of common stock reserved for future issuance under our 2020 Inducement Plan as of December 31, 2022; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 3,147,743 shares of common stock reserved for future issuance under our 2015 Employee Stock Purchase Plan, or the ESPP, as of December 31, 2022, plus any future increases in the number of shares of common stock reserved for issuance under the ESPP pursuant to the evergreen provision of the ESPP.

In addition, unless we specifically state otherwise, all information in this prospectus supplement assumes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • no exercise of outstanding stock options after December 31, 2022; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • no vesting of restricted stock units after December 31, 2022.

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#### RISK FACTORS
 *Investing in our common stock involves significant risks. In addition to the other information contained in this prospectus supplement, the accompanying prospectus and in the documents that we have incorporated by reference, you should carefully consider the risks discussed below and under the heading "Risk Factors" in our [Annual Report on Form 10-K for the fiscal year ended December 31, 2022, filed with the SEC on February 16, 2023](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm), as updated by our subsequent filings under the Exchange Act, before making a decision about investing in our common stock. Such risks and uncertainties and those discussed below are not the only ones facing us. Additional risks and uncertainties not presently known to us, or that we currently see as immaterial, may also harm our business. If any of these risks occur, our business, financial condition and operating results could be harmed, the trading price of our common stock could decline and you could lose part or all of your investment.* 

#### Risks Related to Our Common Stock and this Offering
 ***The price of our common stock historically has been and may in the future be volatile and fluctuate substantially, which may affect the price at which you could sell the common stock.***

Our stock price has been, and in the future may be, subject to substantial volatility. In addition, the stock market in general, and Nasdaq-listed and biopharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. For example, our stock traded within a range of a high price of $85.17 per share on February 15, 2022 and a low price of $40.78 per share on November 9, 2022 in the twelve-month period ending on February 15, 2023. As a result of this volatility, our stockholders could incur substantial losses. In addition, the market price for our common stock may be influenced by many factors, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the success of competitive drugs or technologies;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • results of clinical trials of our drug candidates or those of our competitors;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • regulatory or legal developments in the U.S. and other countries;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • developments or disputes concerning patent applications, issued patents or other proprietary rights;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the recruitment or departure of key personnel;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the level of expenses related to any of our drug candidates or clinical development programs;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the results of our efforts to discover, develop, acquire or in-license additional drug candidates or drugs;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • actual or anticipated changes in estimates as to financial results, development timelines or recommendations by securities analysts;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • variations in our financial results or those of companies that are perceived to be similar to us;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • changes in the structure of healthcare payment systems;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • market conditions in the pharmaceutical and biotechnology sectors;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • general economic, industry and market conditions; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • other risks and uncertainties described in these risk factors.

These and other market and industry factors may cause the market price and demand for our common stock to fluctuate substantially, regardless of our actual operating performance, which may limit or prevent investors from readily selling their shares of common stock and may otherwise negatively affect the liquidity of our common stock. In the past, when the market price of a stock has been volatile, holders of that stock have instituted securities class action litigation against the company that issued the stock. If any of our stockholders brought a lawsuit against us, we could incur substantial costs defending the lawsuit. Such a lawsuit could also divert the time and attention of our management.

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 ***We have broad discretion in how we use the proceeds of this offering, as well as our existing cash, cash equivalents and investments, and may not use them effectively, which could affect our results of operations and cause our stock price to decline.***

We will have considerable discretion in the application of the net proceeds of this offering, including for any of the purposes described in the section entitled "Use of Proceeds," as well as our existing cash, cash equivalents and investments, and you will be relying on the judgment of our management regarding such application. You will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. As a result, investors will be relying upon management's judgment with only limited information about our specific intentions for the use of the balance of the net proceeds of this offering. We may use the net proceeds for purposes that do not yield a significant return or any return at all for our stockholders. In addition, pending their use, we may invest the net proceeds from this offering in a manner that does not produce income or that loses value.

 ***Our executive officers, directors, principal stockholders and their affiliates maintain the ability to exercise significant influence over our company and all matters submitted to stockholders for approval.***

Our executive officers, directors and stockholders who own more than 5% off our outstanding common stock, together with their affiliates and related persons, beneficially own shares of common stock representing a significant percentage of our capital stock. As a result, if these stockholders were to choose to act together, they would be able to influence our management and affairs and the outcome of matters submitted to our stockholders for approval, including the election of directors and any sale, merger, consolidation, or sale of all or substantially all of our assets. This concentration of voting power could delay or prevent an acquisition of our company on terms that other stockholders may desire.

In addition, this concentration of ownership might adversely affect the market price of our common stock by:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • delaying, deferring or preventing a change of control of us;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • impeding a merger, consolidation, takeover or other business combination involving us; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • discouraging a potential acquirer from making a tender offer or otherwise attempting to obtain control of us.

#### If you purchase our common stock in this offering, you will incur immediate and substantial dilution in the book value of your shares.
The offering price per share in this offering may exceed the as adjusted net tangible book value per share of our common stock outstanding prior to this offering. Assuming that an aggregate of 6,813,536 shares of our common stock are sold at a price of $44.03 per share, the last reported sale price of our common stock on the Nasdaq Global Select Market on February 15, 2023, for aggregate gross proceeds of $300.0 million, and after deducting commissions and estimated offering expenses payable by us, you will experience immediate dilution of $31.96 per share based on the difference between our as adjusted net tangible book value per share as of December 31, 2022 after giving effect to this offering and the assumed offering price.

This dilution is due to the substantially lower price paid by some of our investors who purchased shares prior to this offering as compared to the assumed price offered to the public in this offering, and the exercise of stock options granted to our employees. In addition, as of December 31, 2022, options to purchase 6,233,451 shares of our common stock at a weighted average exercise price of $69.14 per share were outstanding, and 1,893,994 shares of our common stock would become issuable upon the vesting and settlement of restricted stock units outstanding as of such date. Each restricted stock unit represents a contingent right to receive one share of our common stock. The exercise of any of these options and the vesting and settlement of any of these restricted stock units would result in additional dilution. As a result of the dilution to investors purchasing shares in this offering, investors may receive significantly less than the assumed purchase price paid in this offering, if anything, in the event of our liquidation. Further, because we may seek to raise additional capital to fund our future activities, we may in the future sell substantial amounts of common stock or securities convertible into or exchangeable for common stock.

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These future issuances of common stock or common stock-related securities, together with the vesting and exercise of outstanding options, the vesting and settlement of outstanding restricted stock units and any additional shares issued in connection with acquisitions, if any, may result in further dilution. For a further description of the dilution that you will experience immediately after this offering, see "Dilution."

#### Sales of a substantial number of shares of our common stock in the public market could cause our stock price to fall.
Sales of a substantial number of shares of our common stock in the public market or the perception that these sales might occur could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. We are unable to predict the effect that sales may have on the prevailing market price of our common stock.

In addition, the sale of substantial amounts of our common stock could adversely impact its price. As of December 31, 2022, 59,958,919 shares of our common stock were outstanding, excluding options to purchase 6,233,451 shares of our common stock, of which 4,187,832 were exercisable as of that date, and 1,893,994 shares of our common stock issuable upon the vesting and settlement of restricted stock units outstanding as of that date. The sale or the availability for sale of a large number of shares of our common stock in the public market could cause the price of our common stock to decline.

#### The actual number of shares we will issue under the Sales Agreement, at any one time or in total, is uncertain.
Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver a placement notice to Cowen at any time throughout the term of the Sales Agreement. The number of shares that are sold by Cowen after delivering a placement notice will fluctuate based on the market price of the shares of common stock during the sales period and limits we set with Cowen. Because the price per share of each share sold will fluctuate based on the market price of our common stock during the sales period, it is not possible at this stage to predict the number of shares that will be ultimately issued.

 ***The common stock offered hereby will be sold in "at the market offerings," and investors who buy shares at different times will likely pay different prices.***

Investors who purchase shares in this offering at different times will likely pay different prices, and so may experience different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares sold, and there is no minimum or maximum sales price. Investors may experience a decline in the value of their shares as a result of share sales made at prices lower than the prices they paid.

 ***The market price of our common stock may be adversely affected by market conditions affecting the stock markets in general, including price and trading fluctuations on the Nasdaq Global Select Market.***

Market conditions may result in volatility in the level of, and fluctuations in, market prices of stocks generally and, in turn, our common stock and sales of substantial amounts of our common stock in the market, in each case being unrelated or disproportionate to changes in our operating performance. Concerns over global stability and economic conditions in the U.S. and abroad have contributed to the extreme volatility of the markets, which may have an effect on the market price of our common stock.

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#### USE OF PROCEEDS
We may offer and sell shares of our common stock having aggregate gross sales proceeds of up to $300,000,000 (before deducting sales agent commissions and expenses). Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time.

We anticipate that we will use the net proceeds to us from this offering to primarily for general corporate purposes, which may include working capital and capital expenditures, expenses related to research, clinical development and commercial efforts, general and administrative expenses, and potential acquisitions of, or investments in, companies, technologies, products or assets that complement our business.

This expected use of the net proceeds from this offering represents our intentions based upon our current plans and business conditions, which could change in the future as our plans and business conditions evolve. The amounts and timing of our actual expenditures may vary significantly depending on numerous factors, including the progress of our development efforts, the status of and results from non-clinical studies and ongoing clinical trials or any clinical trials we may commence in the future, the scope and results of our regulatory activities, the nature and scope of our commercial activities and future products, the success of our current or future collaborations, partnerships and license arrangements, and any unforeseen cash needs. As a result, our management will retain broad discretion over the allocation of the net proceeds from this offering.

Pending our use of the net proceeds from this offering, we intend to invest the net proceeds in a variety of capital preservation investments, including short-term, investment-grade, interest-bearing instruments and U.S. government securities.

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#### DILUTION
If you invest in our common stock in this offering, your ownership interest will be diluted to the extent of the difference between the price per share of our common stock in this offering and the as adjusted net tangible book value per share of our common stock immediately after this offering.

As of December 31, 2022, we had net tangible book value of approximately $514.7 million, or $8.58 per share of our common stock, based upon 59,958,919 shares of our common stock outstanding as of that date. Historical net tangible book value per share is equal to our total tangible assets, less total liabilities, divided by the number of outstanding shares of our common stock. Dilution in net tangible book value per share represents the difference between the amount per share paid by purchasers of shares of common stock in this offering and the net tangible book value per share of our common stock immediately after this offering.

After giving effect to the assumed sale of 6,813,536 shares of common stock in this offering at an assumed offering price of $44.03 per share, the last reported sale price of our common stock on the Nasdaq Global Select Market on February 15, 2023, and after deducting commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of December 31, 2022 would have been approximately $805.7 million, or approximately $12.07 per share of common stock. This represents an immediate increase in as adjusted net tangible book value of $3.49 per share to our existing stockholders and an immediate dilution of $31.96 per share to investors participating in this offering.

Dilution per share to new investors is determined by subtracting net tangible book value per share after this offering from the assumed offering price per share paid by new investors. The following table illustrates this per share dilution:

---

| | | |
|:---|:---|:---|
| Assumed offering price per share  |  | $44.03 |
| &nbsp;&nbsp;&nbsp; Historical net tangible book value per share as of December 31, 2022  | $8.58 |  |
| &nbsp;&nbsp;&nbsp; Increase in net tangible book value per share attributable to new investors  | $3.49 |  |
| As adjusted net tangible book value per share after this offering  |  | $12.07 |
| Dilution per share to new investors  |  | $31.96 |

---

The as adjusted information is illustrative only and will adjust based on the actual offering price, the actual number of shares sold and other terms of the offering determined at the time shares of our common stock are sold pursuant to this prospectus supplement. The as adjusted information assumes that all of our common stock in the aggregate amount of $300.0 million is sold at the assumed offering price of $44.03 per share, the last reported sale price of our common stock on The Nasdaq Global Select Market on February 15, 2023. The shares sold in this offering, if any, will be sold from time to time at various prices.

The foregoing table and discussion is based on 59,958,919 shares of common stock outstanding as of December 31, 2022, and excludes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 6,233,451 shares of common stock issuable upon the exercise of stock options outstanding as of December 31, 2022, at a weighted average exercise price of $69.14 per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 1,893,994 shares of common stock issuable upon the vesting and settlement of restricted stock units outstanding as of December 31, 2022;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 4,116,893 shares of common stock reserved for future issuance under our 2015 Plan as of December 31, 2022;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 1,473,235 shares of common stock reserved for future issuance under our 2020 Inducement Plan as of December 31, 2022; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 3,147,743 shares of common stock reserved for future issuance under our 2015 Employee Stock Purchase Plan as of December 31, 2022.

The table above assumes for illustrative purposes that an aggregate of 6,813,536 shares of our common stock are sold during the term of the sales agreement with Cowen at a price of $44.03 per share, the last

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reported sale price of our common stock on the Nasdaq Global Select Market on February 15, 2023, for aggregate gross proceeds of approximately $300.0 million.

To the extent that any options are vested and exercised or any restricted stock units are vested and settled, new options or restricted stock units are issued under our equity incentive plans, or we otherwise issue additional shares of common stock in the future (including shares issued in connection with acquisitions), there will be further dilution to new investors.

In addition, we may choose to raise additional capital due to market conditions or strategic considerations, even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

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#### PLAN OF DISTRIBUTION
We have entered into a sales agreement with Cowen, under which we may issue and sell from time to time up to $300,000,000 of our common stock through or to Cowen as our sales agent or principal. Sales of our common stock, if any, will be made at market prices by any method that is deemed to be an "at the market offering" as defined in Rule 415 under the Securities Act.

Cowen will offer our common stock subject to the terms and conditions of the sales agreement on a daily basis or as otherwise agreed upon by us and Cowen. We will designate the maximum amount of common stock to be sold through Cowen on a daily basis or otherwise determine such maximum amount together with Cowen. Subject to the terms and conditions of the sales agreement, Cowen will use its commercially reasonable efforts to sell on our behalf all of the shares of common stock requested to be sold by us. We may instruct Cowen not to sell common stock if the sales cannot be effected at or above the price designated by us in any such instruction. Cowen or we may suspend the offering of our common stock being made through Cowen under the sales agreement upon proper notice to the other party. Cowen and we each have the right, by giving written notice as specified in the sales agreement, to terminate the sales agreement in each party's sole discretion at any time.

The aggregate compensation payable to Cowen as sales agent equals up to 3.0% of the gross sales price of the shares sold through it pursuant to the sales agreement. We have also agreed to reimburse Cowen for certain of their expenses up to an amount of $60,000. We estimate that the total expenses of the offering payable by us, excluding commissions payable to Cowen under the sales agreement, will be approximately $125,000.

The remaining sales proceeds, after deducting any expenses payable by us and any transaction fees imposed by any governmental, regulatory, or self-regulatory organization in connection with the sales, will equal our net proceeds for the sale of such common stock.

Cowen will provide written confirmation to us following the close of trading on The Nasdaq Global Select Market on each day in which common stock is sold through it as sales agent under the sales agreement. Each confirmation will include the number of shares of common stock sold through it as sales agent on that day, the volume weighted average price of the shares sold, the percentage of the daily trading volume and the net proceeds to us.

We will report at least quarterly the number of shares of common stock sold through Cowen under the sales agreement, the net proceeds to us and the compensation paid by us to Cowen in connection with the sales of common stock.

Settlement for sales of common stock will occur, unless the parties agree otherwise, on the second business day that is also a trading day following the date on which any sales were made in return for payment of the net proceeds to us. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

Under the sales agreement, we may also sell shares of common stock to Cowen as principal for its own account, at a price to be agreed upon at the time of sale. If we sell shares to a Cowen as principal, we will enter into a separate terms agreement with Cowen, and we will describe the agreement in a separate prospectus supplement or pricing supplement.

In connection with the sales of our common stock on our behalf, Cowen will be deemed to be an "underwriter" within the meaning of the Securities Act, and the compensation paid to Cowen will be deemed to be underwriting commissions or discounts. We have agreed in the sales agreement to provide indemnification and contribution to Cowen against certain liabilities, including liabilities under the Securities Act. As sales agent, Cowen will not engage in any transactions that stabilizes our common stock.

Our common stock is listed on The Nasdaq Global Select Market and trades under the symbol "BPMC." The transfer agent of our common stock is Computershare Trust Company, N.A.

Cowen and/or its affiliates have provided, and may in the future provide, various investment banking and other financial services for us for which services they have received and, may in the future receive, customary fees.

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#### LEGAL MATTERS
Certain legal matters in connection with this offering will be passed upon for us by Goodwin Procter LLP, Boston, Massachusetts. Cowen is being represented in this offering by Latham & Watkins LLP.

#### EXPERTS
The consolidated financial statements of Blueprint Medicines Corporation appearing in Blueprint Medicines Corporation's [Annual Report (Form 10-K) for the year ended December 31, 2022](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm), and the effectiveness of Blueprint Medicines Corporation's internal control over financial reporting as of December 31, 2022, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon included therein, and incorporated herein by reference. Such financial statements are, and audited financial statements to be included in subsequently filed documents will be, incorporated herein in reliance upon the reports of Ernst & Young LLP pertaining to such financial statements and the effectiveness of our internal control over financial reporting as of the respective dates (to the extent covered by consents filed with the Securities and Exchange Commission) given on the authority of such firm as experts in accounting and auditing.

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#### PROSPECTUS

### Blueprint Medicines Corporation

### Common Stock Preferred Stock Debt Securities Purchase Contracts Purchase Units Warrants
We may offer and sell securities from time to time in one or more offerings. This prospectus describes the general terms of these securities and the general manner in which these securities will be offered. We will provide the specific terms of these securities in one or more supplements to this prospectus. The prospectus supplements will also describe the specific manner in which these securities will be offered and may also supplement, update or amend information contained in this document. You should read this prospectus and any applicable prospectus supplement or amendment carefully before you invest in our securities.

We may offer these securities in amounts, at prices and on terms determined at the time of offering. The securities may be sold directly to you, through agents, or through underwriters and dealers. If agents, underwriters or dealers are used to sell the securities, we will name them and describe their compensation in a prospectus supplement.

Our common stock is listed on The Nasdaq Global Select Market under the symbol "BPMC."

 **Investing in these securities involves significant risks. See "Risk Factors" included in any accompanying prospectus supplement and in the documents incorporated by reference in this prospectus for a discussion of the factors you should carefully consider before deciding to purchase these securities.** 

 **Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.** 

The date of this prospectus is February 17, 2023

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#### **TABLE OF CONTENTS**

---

| | |
|:---|:---|
| [ABOUT THIS PROSPECTUS](#tATP)  | [1](#tATP) |
| [RISK FACTORS](#tRIFA)  | [2](#tRIFA) |
| [WHERE YOU CAN FIND MORE INFORMATION](#tWYCF)  | [3](#tWYCF) |
| [INCORPORATION BY REFERENCE](#tIBR)  | [4](#tIBR) |
| [CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS](#tCSRF)  | [5](#tCSRF) |
| [BLUEPRINT MEDICINES CORPORATION](#tBMC)  | [7](#tBMC) |
| [USE OF PROCEEDS](#tUOP)  | [8](#tUOP) |
| [DILUTION](#tDIL)  | [9](#tDIL) |
| [DESCRIPTION OF CAPITAL STOCK](#tDOCS)  | [10](#tDOCS) |
| [DESCRIPTION OF DEBT SECURITIES](#tDODS)  | [17](#tDODS) |
| [DESCRIPTION OF PURCHASE CONTRACTS AND PURCHASE UNITS](#tDOPC)  | [24](#tDOPC) |
| [DESCRIPTION OF WARRANTS](#tDOW)  | [25](#tDOW) |
| [PLAN OF DISTRIBUTION](#tPOD)  | [26](#tPOD) |
| [LEGAL MATTERS](#tLEMA)  | [29](#tLEMA) |
| [EXPERTS](#tEXP)  | [29](#tEXP) |

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#### ABOUT THIS PROSPECTUS
This prospectus is part of an automatic registration statement that we filed with the Securities and Exchange Commission, which we refer to as the SEC, utilizing a "shelf" registration process as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended, or the Securities Act. Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus in one or more offerings.

This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and the accompanying prospectus supplement together with the additional information described under the heading "Where You Can Find More Information" beginning on page [3](#tWYCF) of this prospectus.

You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus filed by us with the SEC. We have not authorized anyone to provide you with different information. This prospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in any accompanying prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful. You should assume that the information appearing in this prospectus, any prospectus supplement, the documents incorporated by reference and any related free writing prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates.

We use "AYVAKIT," "AYVAKYT," "GAVRETO" and "Blueprint Medicines" as trademarks in the United States and other countries. We use and have registered "AYVAKIT," "AYVAKYT," "GAVRETO" and "Blueprint Medicines" in the United States. This prospectus and the information incorporated herein by reference contains references to trademarks, service marks and trade names owned by us or other companies. Solely for convenience, trademarks, service marks and trade names referred to in this prospectus and the information incorporated herein, including logos, artwork, and other visual displays, may appear without the <sup>®</sup> or™ symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the rights of the applicable licensor to these trademarks, service marks and trade names. We do not intend our use or display of other companies' trade names, service marks or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies. All trademarks, service marks and trade names included or incorporated by reference into this prospectus, any applicable prospectus supplement or any related free writing prospectus are the property of their respective owners.

Unless otherwise stated, all references in this prospectus, any applicable prospectus supplement, and any related free writing prospectus, to "us", "our", "Blueprint", "Blueprint Medicines", "we", the "Company" and similar designations refer, collectively, to Blueprint Medicines Corporation, a Delaware corporation, and its consolidated subsidiaries.

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#### RISK FACTORS
Investing in our securities involves significant risks. You should carefully consider the risks and uncertainties described in this prospectus and any accompanying prospectus supplement, including the risk factors set forth in our filings with the SEC that are incorporated by reference herein, including the risk factors in our [Annual Report on Form 10-K for the fiscal year ended December 31, 2022](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm), which is on file with the SEC and is incorporated herein by reference, and any of our subsequent filings with the SEC, before making an investment decision pursuant to this prospectus and any accompanying prospectus supplement relating to a specific offering.

Our business, financial condition and results of operations could be materially and adversely affected by any or all of these risks or by additional risks and uncertainties not presently known to us or that we currently deem immaterial that may adversely affect us in the future.

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#### WHERE YOU CAN FIND MORE INFORMATION
We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at www.blueprintmedicines.com. Our website is not a part of this prospectus and is not incorporated by reference in this prospectus.

This prospectus is part of a registration statement we filed with the SEC. This prospectus omits some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information on us and our consolidated subsidiary and the securities we are offering. Statements in this prospectus concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings. You should review the complete document to evaluate these statements. You can obtain a copy of the registration statement from the SEC at the address listed above or from the SEC's website.

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#### INCORPORATION BY REFERENCE
The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below (File No. 001-37359) and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed) until the offering of the securities under the registration statement is terminated or completed:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [Annual Report on Form 10-K for the fiscal year ended December 31, 2022, which was filed with the SEC on February 16, 2023;](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • The information specifically incorporated by reference into our [Annual Report on Form 10-K for](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837022001316/bpmc-20211231x10k.htm) [the fiscal year ended December 31, 2021](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837022001316/bpmc-20211231x10k.htm) from our [definitive proxy statement (other than information furnished rather than filed) for the 2022 Annual Meeting of Stockholders, which was filed with the SEC on April 29, 2022;](http://www.sec.gov/Archives/edgar/data/1597264/000155837022006381/tmb-20220621xdef14a.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Current Reports on Form 8-K which were filed with the SEC on [January 6, 2023](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000110465923001876/tm232336d1_8k.htm) and [February 10, 2023](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000110465923017984/tm236270d1_8k.htm); and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [The description of our common stock contained in our Registration Statement on Form 8-A which was filed with the SEC on April 27, 2015, including any amendments or reports filed for the purpose of updating such description.](http://www.sec.gov/Archives/edgar/data/1597264/000110465915030565/a15-4342_98a12b.htm)

You may request a copy of these filings, at no cost, by contacting us, either orally or in writing, at the following:

Blueprint Medicines Corporation

45 Sidney Street

Cambridge, Massachusetts 02139

Attn: Investor Relations

Phone: (617) 714-6674

E-mail: ir@blueprintmedicines.com

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#### CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
This prospectus and the information incorporated by reference in this prospectus include "forward-looking statements" within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. All statements, other than statements of historical facts, contained or incorporated by reference in this prospectus are forward-looking statements. In some cases, you can identify forward-looking statements by words such as "aim," "anticipate," "believe," "contemplate," "continue," "could," "estimate," "expect," "intend," "may," "plan," "potential," "predict," "project," "seek," "should," "target," "will," "would" or the negative of these words or other comparable terminology, although not all forward-looking statements contain these identifying words. Forward-looking statements include, but are not limited to, statements about: the timing or likelihood of regulatory actions, filings and approvals for our current and future drug candidates, including our ability to obtain marketing approval for avapritinib and pralsetinib for additional indications or in additional geographies; our ability and plans in continuing to build out our commercial infrastructure and successfully launching, marketing and selling AYVAKIT (avapritinib) (marketed in Europe under the brand name AYVAKYT), GAVRETO (pralsetinib) and any current and future drug candidates for which we receive marketing approval; our expectations regarding the potential benefits of AYVAKIT/AYVAKYT and any current and future drug candidates in treating patients with indolent SM and advanced SM; the rate and degree of market acceptance of AYVAKIT/AYVAKYT and any current and future drug candidates for which we receive marketing approval; the pricing and reimbursement of AYVAKIT/AYVAKYT and any current and future drug candidates for which we receive marketing approval; the initiation, timing, progress and results of our preclinical studies and clinical trials, including our ongoing clinical trials and any planned clinical trials for our current and future drug candidates and research and development programs; our ability to advance drug candidates into, and successfully complete, clinical trials; our ability to successfully develop manufacturing processes for any of our current and future drugs or drug candidates and to secure manufacturing, packaging and labeling arrangements for development activities and commercial production; the implementation of our business model and strategic plans for our business, drugs, drug candidates, platform and technology; the scope and length of protection we are able to establish and maintain for intellectual property rights covering our current and future drugs, drug candidates and technology; the potential benefits of our collaboration with F. Hoffmann-La Roche Ltd and Genentech, Inc. to develop and commercialize pralsetinib globally (excluding Greater China), our cancer immunotherapy collaboration with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc., our collaboration with CStone Pharmaceuticals to develop and commercialize avapritinib, pralsetinib and fisogatinib in Greater China, our collaboration with Zai Lab to develop and commercialize BLU-525 and BLU-945, and any respective back-up forms and certain other forms thereof, as inhibitors of epidermal growth factor receptor (EGFR) in Greater China, our collaboration with Oncopia Therapeutics, Inc., d/b/a Proteovant Therapeutics, Inc. (Proteovant), to research and advance novel targeted protein degrader therapies to address medical needs in oncology and hematology, as well as our ability to maintain these collaborations and establish additional strategic collaborations; the potential benefits of our exclusive license agreement with Clementia Pharmaceuticals, Inc., a wholly-owned subsidiary of Ipsen S.A., to develop and commercialize BLU-782 for fibrodysplasia ossificans progressiva; the potential benefits of our strategic financing transactions with Garnich Adjacent Investments S.a.r.l. and Royalty Pharma Investments 2019 ICAV and the potential acceleration of our commercial products and pipeline resulting from the non-dilutive growth capital; the potential benefits of our license agreement with IDRx, Inc. to develop our development candidate-stage KIT exon 13 inhibitor, IDRX-73, for the treatment of drug-resistant mutations of non-PDGFR-driven gastrointestinal stromal tumor; the development of companion diagnostic tests for our current or future drugs or drug candidates; our financial performance, estimates of our revenues, expenses and capital requirements and our needs for future financing, including our ability to achieve a self-sustainable financial profile; developments relating to our competitors and our industry; the actual or potential benefits of designations granted by the U.S. Food and Drug Administration, or FDA, such as orphan drug, fast track and breakthrough therapy designation or priority review; the impact and scope of the ongoing COVID-19 pandemic on our business, operations, strategy, goals and anticipated milestones, including our ongoing and planned research and discovery activities, ability to conduct ongoing and planned clinical trials, clinical supply of our current or future drug candidates or third-party products intended for use as combination therapies or as comparator agents, and the launch, marketing, sale and commercial supply of AYVAKIT/AYVAKYT, GAVRETO and any current or future drug candidates for which we receive marketing approval.

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Any forward-looking statements contained or incorporated by reference in this prospectus reflect our current views with respect to future events or to our future financial performance and involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. See "Risk Factors" for more information. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures or investments we may make or enter into. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, whether as a result of new information, future events or otherwise.

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#### BLUEPRINT MEDICINES CORPORATION
We are a global precision therapy company that is inventing life-changing medicines for people with cancer and blood disorders. Applying an approach that is both precise and agile, we create therapies that selectively target genetic drivers, with the goal of staying one step ahead across stages of disease. Since 2011, we have leveraged our research platform, including expertise in molecular targeting and world-class drug design capabilities, to rapidly and reproducibly translate science into a broad pipeline of precision therapies. Today, we are delivering our approved medicines, AYVAKIT®/AYVAKYT® (avapritinib) and GAVRETO® (pralsetinib), to patients in the U.S. and Europe, and we are globally advancing multiple programs for systemic mastocytosis, or SM, lung cancer, breast cancer and other genomically defined cancers, and cancer immunotherapy.

Our drug discovery approach combines our biological insights with our proprietary compound library and chemistry expertise to design highly selective and potent precision therapies. We aim to enable potent target inhibition that provides significant and durable clinical responses, limit side effects driven by off-target activity and combine therapies to shut down disease drivers and resistance, with the goal of delivering significant and durable clinical benefit to patients based on the genetic driver of their disease. This uniquely targeted, scalable approach is designed to empower the rapid design and development of new treatments and increase the likelihood of success. In addition, our business model integrates our research engine with robust clinical development and commercial capabilities in oncology and hematology to create a cycle of innovation.

We were incorporated in Delaware in October 2008. Our mailing address and principal executive offices are located at 45 Sidney Street, Cambridge, Massachusetts 02139, and our telephone number is (617) 374-7580. We maintain an Internet website at the following address: www.blueprintmedicines.com. The information on, or that can be accessed through, our website does not constitute part of this prospectus, and you should not rely on any such information in making the decision whether to purchase our common stock. Our common stock trades on the Nasdaq Global Select Market under the symbol "BPMC".

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#### USE OF PROCEEDS
We intend to use the net proceeds from the sale of any securities offered under this prospectus for general corporate purposes unless the applicable prospectus supplement provides otherwise. General corporate purposes may include research and development costs of our drug candidates and to discover additional drug candidates, commercialization cost for any approved drugs, the acquisition or licensing of other drugs or drug candidates, business or technologies, working capital and capital expenditures. We may temporarily invest the net proceeds in a variety of capital preservation instruments, including short-term, investment grade, interest bearing instruments and U.S. government securities, until they are used for their stated purpose. We have not determined the amount of net proceeds to be used specifically for such purposes. As a result, management will retain broad discretion over the allocation of net proceeds.

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#### DILUTION
If there is a material dilution of the purchasers' equity interest from the sale of common equity securities offered under this prospectus, we will set forth in any prospectus supplement the following information regarding any such material dilution of the equity interests of purchasers purchasing securities in an offering under this prospectus:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the net tangible book value per share of our equity securities before and after the offering;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the amount of the increase in such net tangible book value per share attributable to the cash payments made by the purchasers in the offering; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the amount of the immediate dilution from the public offering price which will be absorbed by such purchasers.

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#### DESCRIPTION OF CAPITAL STOCK
The following description of our capital stock is intended as a summary only. This description is based upon, and is qualified by reference to, our amended and restated certificate of incorporation, or certificate of incorporation, our amended and restated bylaws, or bylaws, and applicable provisions of the Delaware General Corporation Law. This summary is not complete. You should read our certificate of incorporation and bylaws, which are filed as exhibits to the registration statement of which this prospectus forms a part, for the provisions that are important to you.

#### Common Stock
*Annual Meeting.* Annual meetings of our stockholders are held on the date designated in accordance with our bylaws. Written notice must be mailed to each stockholder entitled to vote not less than ten nor more than 60 days before the date of the meeting. The presence in person or by proxy of the holders of record of a majority of our issued and outstanding shares entitled to vote at such meeting constitutes a quorum for the transaction of business at meetings of the stockholders. Special meetings of the stockholders may be called for any purpose by the board of directors and shall be called by the chairman of the board or the secretary upon the written request, stating the purpose of such meeting, of the holders of a majority of the outstanding shares of all classes of capital stock entitled to vote at the meeting. Except as may be otherwise provided by applicable law, our certificate of incorporation or our bylaws, all elections shall be decided by a plurality, and all other questions shall be decided by a majority, of the votes cast by stockholders entitled to vote thereon at a duly held meeting of stockholders at which a quorum is present.

*Voting Rights*. Each holder of common stock is entitled to one vote for each share held on all matters to be voted upon by stockholders.

*Dividends*. The holders of common stock, after any preferences of holders of any preferred stock, are entitled to receive dividends when and if declared by the board of directors out of legally available funds.

*Liquidation and Dissolution*. If we are liquidated or dissolved, the holders of the common stock will be entitled to share in our assets available for distribution to stockholders in proportion to the amount of common stock they own. The amount available for common stockholders is calculated after payment of liabilities. Holders of any preferred stock will receive a preferential share of our assets before the holders of the common stock receive any assets.

*Other Rights*. Holders of the common stock have no right to convert the stock into any other security, have the stock redeemed or purchase additional stock or to maintain their proportionate ownership interest. The common stock does not have cumulative voting rights. Holders of shares of the common stock are not required to make additional capital contributions.

*Nasdaq Global Select Market.* Our common stock is listed on The Nasdaq Global Select Market under the trading symbol "BPMC."

*Transfer Agent and Registrar.* Computershare Trust Company, N.A. is the transfer agent and registrar for our common stock.

#### Preferred Stock
We are authorized to issue "blank check" preferred stock, which may be issued in one or more series upon authorization of our board of directors. Our board of directors is authorized to fix the designation of the series, the number of authorized shares of the series, dividend rights and terms, conversion rights, voting rights, redemption rights and terms, liquidation preferences and any other rights, powers, preferences and limitations applicable to each series of preferred stock. The authorized shares of our preferred stock are available for issuance without further action by our stockholders, unless such action is required by applicable law or the rules of any stock exchange on which our securities may be listed. If the approval of our stockholders is not required for the issuance of shares of our preferred stock, our board may determine not to seek stockholder approval. The specific terms of any series of preferred stock offered pursuant to this prospectus will be described in the prospectus supplement relating to that series of preferred stock.

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A series of our preferred stock could, depending on the terms of such series, impede the completion of a merger, tender offer or other takeover attempt. Our board of directors will make any determination to issue shares of preferred stock based upon its judgment as to the best interests of our stockholders. Our board of directors, in so acting, could issue preferred stock having terms that could discourage an acquisition attempt through which an acquirer may be able to change the composition of our board of directors, including a tender offer or other transaction that some, or a majority, of our stockholders might believe to be in their best interests or in which stockholders might receive a premium for their stock over the then-current market price of the stock.

The preferred stock has the terms described below unless otherwise provided in the prospectus supplement relating to a particular series of preferred stock. You should read the prospectus supplement relating to the particular series of preferred stock being offered for specific terms, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the designation and stated value per share of the preferred stock and the number of shares offered;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the amount of liquidation preference per share;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the price at which the preferred stock will be issued;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the dividend rate, or method of calculation of dividends, the dates on which dividends will be payable, whether dividends will be cumulative or noncumulative and, if cumulative, the dates from which dividends will commence to accumulate;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any redemption or sinking fund provisions;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if other than the currency of the United States, the currency or currencies including composite currencies in which the preferred stock is denominated and/or in which payments will or may be payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any conversion provisions; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any other rights, preferences, privileges, limitations and restrictions on the preferred stock.

The preferred stock will, when issued, be fully paid and nonassessable. Unless otherwise provided in the applicable prospectus supplement, each series of preferred stock will rank equally as to dividends and liquidation rights in all respects with each other series of preferred stock. The rights of holders of shares of each series of preferred stock will be subordinate to those of our general creditors.

*Rank*. Unless otherwise provided in the applicable prospectus supplement, the preferred stock will, with respect to dividend rights and rights upon our liquidation, dissolution or winding up of our affairs, rank:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • senior to our common stock and to all equity securities ranking junior to such preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • on a parity with all equity securities issued by us, the terms of which specifically provide that such equity securities rank on a parity with the preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • junior to all equity securities issued by us, the terms of which specifically provide that such equity securities rank senior to the preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs.

The term "equity securities" does not include convertible debt securities.

*Dividends*. Holders of the preferred stock of each series will be entitled to receive, when, as and if declared by our board of directors, cash dividends at such rates and on such dates described in the prospectus supplement. Different series of preferred stock may be entitled to dividends at different rates or based on different methods of calculation. The dividend rate may be fixed or variable or both. Dividends will be payable to the holders of record as they appear on our stock books on record dates fixed by our board of directors, as specified in the applicable prospectus supplement.

Dividends on any series of preferred stock may be cumulative or noncumulative, as described in the applicable prospectus supplement. If our board of directors does not declare a dividend payable on a

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dividend payment date on any series of noncumulative preferred stock, then the holders of that noncumulative preferred stock will have no right to receive a dividend for that dividend payment date, and we will have no obligation to pay the dividend accrued for that period, whether or not dividends on that series are declared payable on any future dividend payment dates. Dividends on any series of cumulative preferred stock will accrue from the date we initially issue shares of such series or such other date specified in the applicable prospectus supplement.

No dividends may be declared or paid or funds set apart for the payment of any dividends on any parity securities unless full dividends have been paid or set apart for payment on the preferred stock. If full dividends are not paid, the preferred stock will share dividends pro rata with the parity securities.

No dividends may be declared or paid or funds set apart for the payment of dividends on any junior securities unless full dividends for all dividend periods terminating on or prior to the date of the declaration or payment will have been paid or declared and a sum sufficient for the payment set apart for payment on the preferred stock.

*Liquidation Preference*. Upon any voluntary or involuntary liquidation, dissolution or winding up of our affairs, then, before we make any distribution or payment to the holders of any common stock or any other class or series of our capital stock ranking junior to the preferred stock in the distribution of assets upon any liquidation, dissolution or winding up of our affairs, the holders of each series of preferred stock shall be entitled to receive out of assets legally available for distribution to stockholders, liquidating distributions in the amount of the liquidation preference per share set forth in the prospectus supplement, plus any accrued and unpaid dividends thereon. Such dividends will not include any accumulation in respect of unpaid noncumulative dividends for prior dividend periods. Unless otherwise provided in the applicable prospectus supplement, after payment of the full amount of their liquidating distributions, the holders of preferred stock will have no right or claim to any of our remaining assets. Upon any such voluntary or involuntary liquidation, dissolution or winding up, if our available assets are insufficient to pay the amount of the liquidating distributions on all outstanding preferred stock and the corresponding amounts payable on all other classes or series of our capital stock ranking on parity with the preferred stock and all other such classes or series of shares of capital stock ranking on parity with the preferred stock in the distribution of assets, then the holders of the preferred stock and all other such classes or series of capital stock will share ratably in any such distribution of assets in proportion to the full liquidating distributions to which they would otherwise be entitled.

Upon any such liquidation, dissolution or winding up and if we have made liquidating distributions in full to all holders of preferred stock, we will distribute our remaining assets among the holders of any other classes or series of capital stock ranking junior to the preferred stock according to their respective rights and preferences and, in each case, according to their respective number of shares. For such purposes, our consolidation or merger with or into any other corporation, trust or entity, or the sale, lease or conveyance of all or substantially all of our property or assets will not be deemed to constitute a liquidation, dissolution or winding up of our affairs.

*Redemption*. If so provided in the applicable prospectus supplement, the preferred stock will be subject to mandatory redemption or redemption at our option, as a whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such prospectus supplement.

The prospectus supplement relating to a series of preferred stock that is subject to mandatory redemption will specify the number of shares of preferred stock that shall be redeemed by us in each year commencing after a date to be specified, at a redemption price per share to be specified, together with an amount equal to all accrued and unpaid dividends thereon to the date of redemption. Unless the shares have a cumulative dividend, such accrued dividends will not include any accumulation in respect of unpaid dividends for prior dividend periods. We may pay the redemption price in cash or other property, as specified in the applicable prospectus supplement. If the redemption price for preferred stock of any series is payable only from the net proceeds of the issuance of shares of our capital stock, the terms of such preferred stock may provide that, if no such shares of our capital stock shall have been issued or to the extent the net proceeds from any issuance are insufficient to pay in full the aggregate redemption price then due, such preferred stock shall automatically and mandatorily be converted into the applicable shares of our capital

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stock pursuant to conversion provisions specified in the applicable prospectus supplement. Notwithstanding the foregoing, we will not redeem any preferred stock of a series unless:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if that series of preferred stock has a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full cumulative dividends on the preferred stock for all past dividend periods and the then current dividend period; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if such series of preferred stock does not have a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full dividends for the then current dividend period.

In addition, we will not acquire any preferred stock of a series unless:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if that series of preferred stock has a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full cumulative dividends on all outstanding shares of such series of preferred stock for all past dividend periods and the then current dividend period; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if that series of preferred stock does not have a cumulative dividend, we have declared and paid or contemporaneously declare and pay or set aside funds to pay full dividends on the preferred stock of such series for the then current dividend period.

However, at any time we may purchase or acquire preferred stock of that series (1) pursuant to a purchase or exchange offer made on the same terms to holders of all outstanding preferred stock of such series or (2) by conversion into or exchange for shares of our capital stock ranking junior to the preferred stock of such series as to dividends and upon liquidation.

If fewer than all of the outstanding shares of preferred stock of any series are to be redeemed, we will determine the number of shares that may be redeemed pro rata from the holders of record of such shares in proportion to the number of such shares held or for which redemption is requested by such holder or by any other equitable manner that we determine. Such determination will reflect adjustments to avoid redemption of fractional shares.

Unless otherwise provided in the applicable prospectus supplement, we will mail notice of redemption at least 30 days but not more than 60 days before the redemption date to each holder of record of preferred stock to be redeemed at the address shown on our stock transfer books. Each notice shall state:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the redemption date;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the number of shares and series of preferred stock to be redeemed;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the redemption price;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the place or places where certificates for such preferred stock are to be surrendered for payment of the redemption price;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • that dividends on the shares to be redeemed will cease to accrue on such redemption date;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the date on which the holder's conversion rights, if any, as to such shares shall terminate; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the specific number of shares to be redeemed from each such holder if fewer than all the shares of any series are to be redeemed.

If notice of redemption has been given and we have set aside the funds necessary for such redemption in trust for the benefit of the holders of any shares called for redemption, then from and after the redemption date, dividends will cease to accrue on such shares, and all rights of the holders of such shares will terminate, except the right to receive the redemption price.

*Voting Rights*. Holders of preferred stock will not have any voting rights, except as required by law or as indicated in the applicable prospectus supplement.

Unless otherwise provided for under the terms of any series of preferred stock, no consent or vote of the holders of shares of preferred stock or any series thereof shall be required for any amendment to our certificate of incorporation that would increase the number of authorized shares of preferred stock or the

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number of authorized shares of any series thereof or decrease the number of authorized shares of preferred stock or the number of authorized shares of any series thereof (but not below the number of authorized shares of preferred stock or such series, as the case may be, then outstanding).

*Conversion Rights*. The terms and conditions, if any, upon which any series of preferred stock is convertible into our common stock will be set forth in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of common stock into which the shares of preferred stock are convertible, the conversion price, rate or manner of calculation thereof, the conversion period, provisions as to whether conversion will be at our option or at the option of the holders of the preferred stock, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption.

*Transfer Agent and Registrar*. The transfer agent and registrar for the preferred stock will be set forth in the applicable prospectus supplement.

#### Effects of Authorized but Unissued Stock
We have shares of common stock and preferred stock available for future issuance without stockholder approval, subject to any limitations imposed by the listing standards of The Nasdaq Global Select Market. We may utilize these additional shares for a variety of corporate purposes, including for future public offerings to raise additional capital or facilitate corporate acquisitions or for payment as a dividend on our capital stock. The existence of unissued and unreserved common stock and preferred stock may enable our board of directors to issue shares to persons friendly to current management or to issue preferred stock with terms that could have the effect of making it more difficult for a third party to acquire, or could discourage a third party from seeking to acquire, a controlling interest in our company by means of a merger, tender offer, proxy contest or otherwise. In addition, if we issue preferred stock, the issuance could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon liquidation.

#### Provisions of our Certificate of Incorporation and Bylaws and Delaware Law That May Have Anti-takeover Effects
Our certificate of incorporation and bylaws include a number of provisions that may have the effect of encouraging persons considering unsolicited tender offers or other unilateral takeover proposals to negotiate with our board of directors rather than pursue non-negotiated takeover attempts. These provisions include the items described below.

*Board Composition and Filling Vacancies.* In accordance with our certificate of incorporation, our board is divided into three classes serving three-year terms, with one class being elected each year. Our certificate of incorporation also provides that directors may be removed only for cause and then only by the affirmative vote of the holders of 75% or more of the shares then entitled to vote at an election of directors. Furthermore, any vacancy on our board of directors, however occurring, including a vacancy resulting from an increase in the size of our board, may only be filled by the affirmative vote of a majority of our directors then in office, even if less than a quorum.

*No Written Consent of Stockholders.* Our certificate of incorporation provides that all stockholder actions are required to be taken by a vote of the stockholders at an annual or special meeting, and that stockholders may not take any action by written consent in lieu of a meeting.

*Meetings of Stockholders.* Our bylaws provide that only a majority of the members of our board of directors then in office may call special meetings of stockholders and only those matters set forth in the notice of the special meeting may be considered or acted upon at a special meeting of stockholders. Our bylaws limit the business that may be conducted at an annual meeting of stockholders to those matters properly brought before the meeting.

*Advance Notice Requirements.* Our bylaws establish advance notice procedures with regard to stockholder proposals relating to the nomination of candidates for election as directors or new business to be brought before meetings of our stockholders. These procedures provide that notice of stockholder proposals must be timely given in writing to our corporate secretary prior to the meeting at which the action

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is to be taken. Generally, to be timely, notice must be received at our principal executive offices not less than 90 days or more than 120 days prior to the first anniversary date of the annual meeting for the preceding year. The notice must contain certain information specified in the by-laws. These provisions may have the effect of precluding the conduct of certain business at a meeting if the proper procedures are not followed. These provisions may also discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer's own slate of directors or otherwise attempting to obtain control of our company.

*Amendment to Certificate of Incorporation and Bylaws.* As required by the Delaware General Corporation Law, any amendment of our certificate of incorporation must first be approved by a majority of our board of directors and, if required by law or our certificate of incorporation, thereafter be approved by a majority of the outstanding shares entitled to vote on the amendment, and a majority of the outstanding shares of each class entitled to vote thereon as a class, except that the amendment of the provisions relating to stockholder action, directors, limitation of liability, exclusive jurisdiction of Delaware Courts and the amendment of our by-laws and certificate of incorporation must be approved by not less than 75% of the outstanding shares entitled to vote on the amendment, and not less than 75% of the outstanding shares of each class entitled to vote thereon as a class. Our by-laws may be amended by the affirmative vote of a majority of the directors then in office, subject to any limitations set forth in the by-laws; and may also be amended by the affirmative vote of at least 75% of the outstanding shares entitled to vote on the amendment, or, if the board of directors recommends that the stockholders approve the amendment, by the affirmative vote of the majority of the outstanding shares entitled to vote on the amendment, in each case voting together as a single class.

*Blank Check Preferred Stock.* Our certificate of incorporation provides for 5,000,000 authorized shares of preferred stock. The existence of authorized but unissued shares of preferred stock may enable our board of directors to render more difficult or to discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise. For example, if in the due exercise of its fiduciary obligations, our board of directors were to determine that a takeover proposal is not in the best interests of us or our stockholders, our board of directors could cause shares of preferred stock to be issued without stockholder approval in one or more private offerings or other transactions that might dilute the voting or other rights of the proposed acquirer or insurgent stockholder or stockholder group. In this regard, our certificate of incorporation grants our board of directors broad power to establish the rights and preferences of authorized and unissued shares of preferred stock. The issuance of shares of preferred stock could decrease the amount of earnings and assets available for distribution to holders of shares of common stock. The issuance may also adversely affect the rights and powers, including voting rights, of these holders and may have the effect of delaying, deterring or preventing a change in control of us.

*Section 203 of the Delaware General Corporation Law.* We are subject to the provisions of Section 203 of the DGCL regulating corporate takeovers. In general, Section 203 prohibits a publicly held Delaware corporation from engaging, under certain circumstances, in a business combination with an interested stockholder for a period of three years following the date the person became an interested stockholder unless:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • upon completion of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the voting stock outstanding, but not for determining the outstanding voting stock owned by the interested stockholder, (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • at or subsequent to the date of the transaction, the business combination is approved by the board of directors of the corporation and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock which is not owned by the interested stockholder.

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Generally, a business combination includes a merger, asset or stock sale, or other transaction resulting in a financial benefit to the interested stockholder. An interested stockholder is a person 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 a corporation's outstanding voting stock. We expect the existence of this provision to have an anti-takeover effect with respect to transactions our board of directors does not approve in advance. We also anticipate that Section 203 of the DGCL may discourage business combinations or other attempts that might result in a premium over the market price for the shares of common stock held by our stockholders.

The provisions of Delaware law and our certificate of incorporation and bylaws could have the effect of discouraging others from attempting hostile takeovers and, as a consequence, may also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions may also have the effect of preventing changes in our management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

*Exclusive Jurisdiction of Certain Actions.* Our certificate of incorporation requires, to the fullest extent permitted by law, that derivative actions brought in our name, actions against our directors, officers and employees for breach of fiduciary duty and other similar actions may be brought only in the Court of Chancery in the State of Delaware. Although we believe this provision benefits us by providing increased consistency in the application of Delaware law in the types of lawsuits to which it applies, the provision may have the effect of discouraging lawsuits against our directors and officers.

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#### DESCRIPTION OF DEBT SECURITIES
We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any debt securities that we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities offered under a prospectus supplement may differ from the terms described below. Unless the context requires otherwise, whenever we refer to the indenture, we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue the debt securities under the indenture that we will enter into with the trustee named in the indenture. The indenture will be qualified under the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act"). We have filed the form of indenture as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part, or will be incorporated by reference from, reports that we file with the SEC.

The following summary of material provisions of the debt securities and the indenture is subject to, and qualified in its entirety by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indenture that contains the terms of the debt securities.

#### General
The indenture does not limit the amount of debt securities that we may issue. It provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit that we may designate. Except for the limitations on consolidation, merger and sale of all or substantially all of our assets contained in the indenture, the terms of the indenture do not contain any covenants or other provisions designed to give holders of any debt securities protection against changes in our operations, financial condition or transactions involving us.

We may issue the debt securities issued under the indenture as "discount securities," which means they may be sold at a discount below their stated principal amount. These debt securities, as well as other debt securities that are not issued at a discount, may be issued with "original issue discount" ("OID") for U.S. federal income tax purposes because of interest payment and other characteristics or terms of the debt securities. Material U.S. federal income tax considerations applicable to debt securities issued with OID will be described in more detail in any applicable prospectus supplement.

We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the title of the series of debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any limit upon the aggregate principal amount that may be issued;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the maturity date or dates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the form of the debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the applicability of any guarantees;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • whether the debt securities rank as senior debt, senior subordinated debt, subordinated debt or any combination thereof, and the terms of any subordination;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if the price (expressed as a percentage of the aggregate principal amount thereof) at which such debt securities will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such debt securities that is convertible into another security or the method by which any such portion shall be determined;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the interest rate or rates, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our right, if any, to defer payment of interest and the maximum length of any such deferral period;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if applicable, the date or dates after which, or the period or periods during which, and the price or prices at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the date or dates, if any, on which, and the price or prices at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder's option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any and all terms, if applicable, relating to any auction or remarketing of the debt securities of that series and any security for our obligations with respect to such debt securities and any other terms which may be advisable in connection with the marketing of debt securities of that series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • whether the debt securities of the series shall be issued in whole or in part in the form of a global security or securities; the terms and conditions, if any, upon which such global security or securities may be exchanged in whole or in part for other individual securities; and the depositary for such global security or securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if applicable, the provisions relating to conversion or exchange of any debt securities of the series and the terms and conditions upon which such debt securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional (at our option or the holders' option) conversion or exchange features, the applicable conversion or exchange period and the manner of settlement for any conversion or exchange;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if other than the full principal amount thereof, the portion of the principal amount of debt securities of the series which shall be payable upon declaration of acceleration of the maturity thereof;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • additions to or changes in the covenants applicable to the particular debt securities being issued, including, among others, the consolidation, merger or sale covenant;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • additions to or changes in the events of default with respect to the securities and any change in the right of the trustee or the holders to declare the principal, premium, if any, and interest, if any, with respect to such securities to be due and payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • additions to or changes in or deletions of the provisions relating to covenant defeasance and legal defeasance;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • additions to or changes in the provisions relating to satisfaction and discharge of the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • additions to or changes in the provisions relating to the modification of the indenture both with and without the consent of holders of debt securities issued under the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • whether interest will be payable in cash or additional debt securities at our or the holders' option and the terms and conditions upon which the election may be made;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the terms and conditions, if any, upon which we will pay amounts in addition to the stated interest, premium, if any and principal amounts of the debt securities of the series to any holder that is not a "United States person" for federal tax purposes;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any restrictions on transfer, sale or assignment of the debt securities of the series; and

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, any other additions or changes in the provisions of the indenture, and any terms that may be required by us or advisable under applicable laws or regulations.

#### Conversion or Exchange Rights
We will set forth in the applicable prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to settlement upon conversion or exchange and whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.

#### Consolidation, Merger or Sale
Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indenture will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of our assets as an entirety or substantially as an entirety. However, any successor to or acquirer of such assets (other than any subsidiary of ours) must assume all of our obligations under the indenture or the debt securities, as appropriate.

#### Events of Default under the Indenture
Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indenture with respect to any series of debt securities that we may issue:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if we fail to pay any installment of interest on any series of debt securities, as and when the same shall become due and payable, and such default continues for a period of 90 days; provided, however, that a valid extension of an interest payment period by us in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of interest for this purpose;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if we fail to pay the principal of, or premium, if any, on any series of debt securities as and when the same shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to such series; provided, however, that a valid extension of the maturity of such debt securities in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of principal or premium, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if we fail to observe or perform any other covenant or agreement contained in the debt securities or the indenture, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive written notice of such failure, requiring the same to be remedied and stating that such is a notice of default thereunder, from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if specified events of bankruptcy, insolvency or reorganization occur.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal of, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or

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events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indenture, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the direction so given by the holder is not in conflict with any law or the applicable indenture; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

A holder of the debt securities of any series will have the right to institute a proceeding under the indenture or to appoint a receiver or trustee, or to seek other remedies only if:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the holder has given written notice to the trustee of a continuing event of default with respect to that series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request,

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • such holders have offered to the trustee indemnity satisfactory to it against the costs, expenses and liabilities to be incurred by the trustee in compliance with the request; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indenture.

#### Modification of Indenture; Waiver
We and the trustee may change an indenture without the consent of any holders with respect to specific matters:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to cure any ambiguity, defect or inconsistency in the indenture or in the debt securities of any series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to comply with the provisions described above under "Description of Debt Securities — Consolidation, Merger or Sale";

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to provide for uncertificated debt securities in addition to or in place of certificated debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to add to our covenants, restrictions, conditions or provisions such new covenants, restrictions, conditions or provisions for the benefit of the holders of all or any series of debt securities, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred upon us in the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to make any change that does not adversely affect the interests of any holder of debt securities of any series in any material respect;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided above under "Description of Debt Securities — General" to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to evidence and provide for the acceptance of appointment under any indenture by a successor trustee; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act.

In addition, under the indenture, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • extending the fixed maturity of any debt securities of any series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any series of any debt securities; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.

#### Discharge
Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • provide for payment;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • register the transfer or exchange of debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • replace stolen, lost or mutilated debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • pay principal of and premium and interest on any debt securities of the series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • maintain paying agencies;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • hold monies for payment in trust;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • recover excess money held by the trustee;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • compensate and indemnify the trustee; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

#### Form, Exchange and Transfer
We will issue the debt securities of each series only in fully registered form without coupons and, unless we provide otherwise in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indenture provides that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company ("DTC") or another depositary named by us and identified in the applicable prospectus supplement with respect to that series. To the extent the debt securities of a series are issued in global form and as book-entry, a description of terms relating to any book-entry securities will be set forth in the applicable prospectus supplement.

At the option of the holder, subject to the terms of the indenture and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any

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series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indenture and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will impose no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

#### Information Concerning the Trustee
The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indenture at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

#### Payment and Paying Agents
Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

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#### Governing Law
The indenture and the debt securities will be governed by and construed in accordance with the laws of the state of New York, except to the extent that the Trust Indenture Act is applicable.

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#### DESCRIPTION OF PURCHASE CONTRACTS AND PURCHASE UNITS
We may issue purchase contracts, including contracts obligating holders to purchase from or sell to us, and obligating us to sell to or purchase from the holders, a specified number of shares of our common stock or preferred stock at a future date or dates, which we refer to in this prospectus as purchase contracts. The price per share of common stock or preferred stock and the number of shares of each may be fixed at the time the purchase contracts are issued or may be determined by reference to a specific formula set forth in the purchase contracts. The purchase contracts may be issued separately or as part of units, often known as purchase units, consisting of one or more purchase contracts and beneficial interests in debt securities or any other securities described in the applicable prospectus supplement or any combination of the foregoing, securing the holders' obligations to purchase the common stock or preferred stock under the purchase contracts.

The purchase contracts may require us to make periodic payments to the holders of the purchase units or vice versa, and these payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under those contracts in a specified manner, including pledging their interest in another purchase contract.

The applicable prospectus supplement will describe the terms of the purchase contracts and purchase units, including, if applicable, collateral or depositary arrangements.

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#### DESCRIPTION OF WARRANTS
We may issue warrants to purchase debt securities, common stock or preferred stock. We may offer warrants separately or together with one or more additional warrants, debt securities, common stock or preferred stock, or any combination of those securities in the form of units, as described in the applicable prospectus supplement. If we issue warrants as part of a unit, the accompanying prospectus supplement will specify whether those warrants may be separated from the other securities in the unit prior to the expiration date of the warrants. The applicable prospectus supplement will also describe the following terms of any warrants:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the specific designation and aggregate number of, and the offering price at which we will issue, the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the currency or currency units in which the offering price, if any, and the exercise price are payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the date on which the right to exercise the warrants will begin and the date on which that right will expire or, if you may not continuously exercise the warrants throughout that period, the specific date or dates on which you may exercise the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • whether the warrants are to be sold separately or with other securities as parts of units;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • whether the warrants will be issued in definitive or global form or in any combination of these forms, although, in any case, the form of a warrant included in a unit will correspond to the form of the unit and of any security included in that unit;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any applicable material U.S. federal income tax consequences;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the identity of the warrant agent for the warrants and of any other depositaries, execution or paying agents, transfer agents, registrars or other agents;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the proposed listing, if any, of the warrants or any securities purchasable upon exercise of the warrants on any securities exchange;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the designation and terms of any equity securities purchasable upon exercise of the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the designation, aggregate principal amount, currency and terms of any debt securities that may be purchased upon exercise of the warrants;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if applicable, the designation and terms of the debt securities, common stock or preferred stock with which the warrants are issued and, the number of warrants issued with each security;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if applicable, the date from and after which any warrants issued as part of a unit and the related debt securities, common stock or preferred stock will be separately transferable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the number of shares of common stock or the number of shares of preferred stock purchasable upon exercise of a warrant and the price at which those shares may be purchased;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • information with respect to book-entry procedures, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the antidilution provisions of, and other provisions for changes to or adjustment in the exercise price of, the warrants, if any;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any redemption or call provisions; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any additional terms of the warrants, including terms, procedures and limitations relating to the exchange or exercise of the warrants.

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#### PLAN OF DISTRIBUTION
We may sell securities:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • to or through underwriters, brokers or dealers;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • through agents;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • directly to one or more other purchasers in negotiated sales or competitively bid transactions;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • in "at the market" offerings, within the meaning of Rule 415(a)(4) of the Securities Act of 1933, as amended, or the Securities Act, to or through a market maker or into an existing trading market, on an exchange or otherwise;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • through a block trade in which the broker or dealer engaged to handle the block trade will attempt to sell the securities as agent, but may position and resell a portion of the block as principal to facilitate the transaction; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • through a combination of any of the above methods of sale.

In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing security holders.

We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers. We will, in the prospectus supplement relating to such offering, name any agent that could be viewed as an underwriter under the Securities Act and describe any commissions that we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

The distribution of the securities may be effected from time to time in one or more transactions:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • at a fixed price, or prices, which may be changed from time to time;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • at market prices prevailing at the time of sale;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • at prices related to such prevailing market prices; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • at negotiated prices.

Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.

The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the name of the agent or any underwriters;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the public offering or purchase price;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any discounts and commissions to be allowed or paid to the agent or underwriters;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • all other items constituting underwriting compensation;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any discounts and commissions to be allowed or paid to dealers; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • any exchanges on which the securities will be listed.

If any underwriters or agents are utilized in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

If a dealer is utilized in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

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If we offer securities in a subscription rights offering to our existing security holders, we may enter into a standby underwriting agreement with dealers, acting as standby underwriters. We may pay the standby underwriters a commitment fee for the securities they commit to purchase on a standby basis. If we do not enter into a standby underwriting arrangement, we may retain a dealer-manager to manage a subscription rights offering for us.

Agents, underwriters, dealers and other persons may be entitled under agreements which they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the purchase by an institution of the securities covered under that contract shall not at the time of delivery be prohibited under the laws of the jurisdiction to which that institution is subject; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if the securities are also being sold to underwriters acting as principals for their own account, the underwriters shall have purchased such securities not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.

Certain agents, underwriters and dealers, and their associates and affiliates may be customers of, have borrowing relationships with, engage in other transactions with, or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.

In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may overallot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise. The applicable prospectus supplement may provide that the original issue date for your securities may be more than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the second business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than two scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.

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In compliance with the guidelines of the Financial Industry Regulatory Authority, or FINRA, the aggregate maximum discount, commission or agency fees or other items constituting underwriting compensation to be received by any FINRA member or independent broker-dealer will not exceed 8% of the proceeds from any offering pursuant to this prospectus and any applicable prospectus supplement.

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#### LEGAL MATTERS
Unless the applicable prospectus supplement indicates otherwise, the validity of the securities in respect of which this prospectus is being delivered will be passed upon by Goodwin Procter LLP, Boston, Massachusetts.

#### EXPERTS
The consolidated financial statements of Blueprint Medicines Corporation appearing in Blueprint Medicines Corporation's [Annual Report (Form 10-K) for the year ended December 31, 2022](http://www.sec.gov/ix?doc=/Archives/edgar/data/1597264/000155837023001465/bpmc-20221231x10k.htm), and the effectiveness of Blueprint Medicines Corporation's internal control over financial reporting as of December 31, 2022, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon included therein, and incorporated herein by reference. Such financial statements are, and audited financial statements to be included in subsequently filed documents will be, incorporated herein in reliance upon the reports of Ernst & Young LLP pertaining to such financial statements and the effectiveness of our internal control over financial reporting as of the respective dates (to the extent covered by consents filed with the Securities and Exchange Commission) given on the authority of such firm as experts in accounting and auditing.

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### Up to $300,000,000
![[MISSING IMAGE: lg_blueprint-4c.jpg]](lg_blueprint-4c.jpg)

### Common Stock

#### PROSPECTUS SUPPLEMENT

### Cowen
February 17, 2023

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## Ex-Filing

**Exhibit 107**

**Calculation of Filing Fee Tables**

**424(b)(5)**

(Form Type)

**Blueprint Medicines Corporation**

(Exact Name of Registrant as Specified in its Charter)

<u>Table 1: Newly Registered and Carry Forward Securities</u>

---

| | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | **Security<br> Type** | **Security Class Title** | **Fee <br> Calculation <br> or Carry<br> Forward <br> Rule** | **Amount<br> Registered** | **Proposed<br> Maximum<br> Offering<br> Price Per<br> Unit** | **Maximum<br> Aggregate<br> Offering<br> Price<sup>(1)</sup>** | **Fee Rate** | **Amount of<br> Registration<br> Fee** | **Carry<br> Forward<br> Form Type** | **Carry<br> Forward File<br> Number** | **Carry<br> Forward Initial<br> effective date** | **Filing Fee<br> Previously<br> Paid In<br> Connection<br> with Unsold<br> Securities to<br> be Carried<br> Forward** |
| Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities | Newly Registered Securities |
| Fees to Be Paid | Equity | Common Stock, par value $0.001 per share | Rule 457(o) and Rule 457(r) | $300000000 | N/A | $300000000 | $0.0001102 | $33060 |  |  |  |  |
| Fees Previously Paid |  |  |  |  |  |  |  |  |  |  |  |  |
| Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities | Carry Forward Securities |
| Carry Forward Securities |  |  |  |  |  |  |  |  |  |  |  |  |
|  | Total Offering Amount | Total Offering Amount | Total Offering Amount | Total Offering Amount | Total Offering Amount | $300000000 |  | $33060 |  |  |  |  |
|  | Total Fees Previously Paid | Total Fees Previously Paid | Total Fees Previously Paid | Total Fees Previously Paid | Total Fees Previously Paid |  |  |  |  |  |  |  |
|  | Total Fee Offsets | Total Fee Offsets | Total Fee Offsets | Total Fee Offsets | Total Fee Offsets |  |  | $27810<sup>(2)</sup> |  |  |  |  |
|  | Net Fee Due | Net Fee Due | Net Fee Due | Net Fee Due | Net Fee Due |  |  | $5250<sup>(2)</sup> |  |  |  |  |

---

&nbsp;&nbsp;&nbsp;&nbsp;(1) The proposed maximum aggregate offering price is being used to calculate
 the registration fee pursuant to Rule 457(o) under the Securities Act of 1933, as amended.

(2) On February 17, 2022, the registrant
 filed a prospectus supplement to the registration statement on Form S-3 dated February 13, 2020 (File No. 333-236424) (the "Prior
 Registration Statement"), registering the issuance of up to $300,000,000 of Common Stock of the registrant in an at-the-market
 equity offering of the registrant's Common Stock (the "Prior ATM Common Stock"). The registration fee associated
 with the Prior ATM Common Stock was $27,810. The registrant sold no Prior ATM Common Stock pursuant to the Prior Registration Statement.
 Accordingly, the unused registration fee paid in connection with the Prior Registration Statement and the Prior ATM Common Stock
 is $27,810. Pursuant to Rule 457(p) under the Securities Act, the registration fee applicable to the $300,000,000 of Common Stock of the registrant
being registered hereby in the amount of $33,060 is offset by $27,810 in registration fees previously paid by the registrant with respect
to Prior ATM Common Stock that were registered but not issued pursuant to the Prior Registration Statement. Accordingly, $5,250 in registration
fees are being paid at this time. Concurrently with the filing of this prospectus supplement, any offering of unsold Prior ATM Common
Stock pursuant to the Prior Registration Statement is hereby terminated.

<u>Table 2: Fee Offset Claims and Sources</u>

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | Registrant <br> or Filer <br> Name | Form <br> or <br> Filing <br> Type | File <br> Number | Initial <br> Filing <br> Date | Filing <br> Date | Fee<br> Offset <br> Claimed |  | Security <br> Type <br> Associated <br> with Fee <br> Offset <br> Claimed | Security <br> Title <br> Associated <br> with Fee <br> Offset <br> Claimed | Unsold <br> Securities <br> Associated <br> with Fee <br> Offset <br> Claimed | Unsold <br> Aggregate <br> Offering <br> Amount <br> Associated <br> with Fee <br> Offset <br> Claimed | Fee<br> Paid <br> with<br> Fee <br> Offset <br> Source |  |
| Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) | Rule 457(b) and 0-11(a)(2) |
| Fee Offset Claims |  |  |  |  |  |  |  |  |  |  |  |  |  |
| Fee Offset Sources |  |  |  |  |  |  |  |  |  |  |  |  |  |
| Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) | Rule 457(p) |
| Fee Offset Claims | Blueprint Medicines Corporation | 424(b)(5) | 333-236424 | February 17, 2022 |  | $27810 | (2) | Equity | Common Stock, par value $0.001 per share |  | $300000000 |  |  |
| Fee Offset Sources | Blueprint Medicines Corporation | 424(b)(5) | 333-236424 |  | February 17, 2022 |  |  |  |  |  |  | $33060 | (2) |

---