For the quarterly period ended March 31, 2015.

For the transition period from                      to                     .

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    ý  YES    ¨  NO

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    ý  YES    ¨  NO

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act):   ¨  YES    ý  NO

As of April 30, 2015, the registrant had 458,424,686 shares of Common Stock outstanding.

We own established pharmaceutical platforms in Chile, Spain, Mexico, and Uruguay, which are generating revenue and which we expect to facilitate future market entry for our products currently in development. In addition, we have established a global supply chain operation and holding company in Ireland. We own a specialty active pharmaceutical ingredients (“APIs”) manufacturer in Israel, which we expect will facilitate the development of our pipeline of molecules and compounds for our proprietary molecular diagnostic and therapeutic products. In the U.S., we own a laboratory certified under the Clinical Laboratory Improvement Amendments of 1988, as amended (“CLIA”), with a urologic focus that generates revenue and serves as the commercial platform for the U.S. launch of the 4Kscore test to improve cancer risk stratification of patient candidates prior to prostate biopsy.

Basis of presentation. The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and notes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments (consisting of only normal recurring adjustments) considered necessary to present fairly the Company’s results of operations, financial position and cash flows have been made. The results of operations and cash flows for the three months ended March 31, 2015, are not necessarily indicative of the results of operations and cash flows that may be reported for the remainder of 2015 or for future periods. The unaudited Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and the Notes to Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2014.

Reclassification and correction of immaterial error. During the first quarter of 2014, we reported payments for contingent consideration and some deferred payments as cash outflows from operating activities. Amounts paid pertaining to the initial purchase accounting contingent liabilities should have been classified as cash outflows from financing activities. Amounts paid in excess of the initial purchase accounting contingent liabilities have been classified as cash outflows from operating activities. We have corrected the amounts previously reported in our Form 10-Q for the three months ended March 31, 2014 in conjunction with the filing of this Form 10-Q by reducing cash outflows from operating activities and increasing cash outflows from financing activities by $6.4 million for the first quarter of 2014.

Principles of consolidation. The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of OPKO Health, Inc. and of our wholly-owned subsidiaries and variable interest entities in which we are deemed to be the primary beneficiary. All intercompany accounts and transactions are eliminated in consolidation.

Use of estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Cash and cash equivalents. Cash and cash equivalents include short-term, interest-bearing instruments with original maturities of 90 days or less at the date of purchase. We also consider all highly liquid investments with original maturities at the date of purchase of 90 days or less as cash equivalents. These investments include money markets, bank deposits, certificates of deposit and U.S. treasury securities.

Inventories. Inventories are valued at the lower of cost or market (net realizable value). Cost is determined by the first-in, first-out method. We consider such factors as the amount of inventory on hand, estimated time required to sell such inventories, remaining shelf-life, and current market conditions to determine whether inventories are stated at the lower of cost or market.

Pre-launch inventories. We may accumulate commercial quantities of certain product candidates prior to the date we anticipate that such products will receive final U.S. FDA approval.  The accumulation of such pre-launch inventories involves the risk that such products may not be approved for marketing by the FDA on a timely basis, or ever.  This risk notwithstanding, we may accumulate pre-launch inventories of certain products when such action is appropriate in relation to the commercial value of the product launch opportunity.  In accordance with our policy, this pre-launch inventory is expensed.  At March 31, 2015 and December 31, 2014, there were no pre-launch inventories.

Goodwill and intangible assets. Goodwill represents the difference between the purchase price and the estimated fair value of the net assets acquired when accounted for by the purchase method of accounting and arose from our acquisitions of Pharma Genexx, S.A. (“OPKO Chile”), Pharmacos Exakta S.A. de C.V. (“OPKO Mexico”), CURNA, Inc. (“CURNA”), Claros Diagnostics, Inc. (“OPKO Diagnostics”), FineTech Pharmaceuticals, Ltd. (“FineTech”), ALS Distribuidora Limitada (“ALS”), Farmadiet Group Holding, S.L. (“OPKO Health Europe”), previously known as OPKO Spain, Prost-Data, Inc. (“OPKO Lab”), Cytochroma Inc. (“OPKO Renal”), Silcon Comércio, Importacao E Exportacao de Produtos Farmaceuticos e Cosmeticos Ltda. (“OPKO Brazil”) and PROLOR Biotech, Inc. (“OPKO Biologics”). Goodwill, in-process research and development (“IPR&D”) and other intangible assets acquired in business combinations, licensing and other transactions at March 31, 2015 and December 31, 2014 were $1.1 billion and $1.1 billion, respectively.

We amortize intangible assets with definite lives on a straight-line basis over their estimated useful lives, currently ranging from 3 to 10 years, and review for impairment at least annually, or when events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. We use the straight-line method of amortization as there is no reliably determinable pattern in which the economic benefits of our intangible assets are consumed or otherwise used up. Amortization expense was $2.7 million and $2.7 million for the three months ended March 31, 2015 and 2014, respectively.

Fair value measurements. The carrying amounts of our cash and cash equivalents, accounts receivable and accounts payable approximate their fair value due to the short-term maturities of these instruments. Investments that are considered available for sale as of March 31, 2015 and December 31, 2014, are carried at fair value.

Short-term investments, which we invest in from time to time, include bank deposits, corporate notes, U.S. treasury securities and U.S. government agency securities with original maturities of greater than 90 days and remaining maturities of less than one year. Long-term investments include corporate notes, U.S. treasury securities and U.S. government agency securities with maturities greater than one year.

Contingent consideration. Each period we revalue the contingent consideration obligations associated with certain acquisitions to their fair value and record increases in the fair value as contingent consideration expense and decreases in the fair value as contingent consideration income. Changes in contingent consideration result from changes in the assumptions regarding probabilities of successful achievement of related milestones, the estimated timing in which the milestones are achieved and the discount rate used to estimate the fair value of the liability. Contingent consideration may change significantly as our development programs progress, revenue estimates evolve and additional data is obtained, impacting our assumptions. The assumptions used in estimating fair value require significant judgment. The use of different assumptions and judgments could result in a materially different estimate of fair value which may have a material impact on our results from operations and financial position.

Derivative financial instruments. We record derivative financial instruments on our Condensed Consolidated Balance Sheet at their fair value and recognize the changes in the fair value in our Condensed Consolidated Statement of Operations, when they occur, the only exception being derivatives that qualify as hedges. For the derivative instrument to qualify as a hedge, we are required to meet strict hedge effectiveness and contemporaneous documentation requirements at the initiation of the hedge and assess the hedge effectiveness on an ongoing basis over the life of the hedge. At March 31, 2015 and December 31, 2014, our forward contracts for inventory purchases did not meet the documentation requirements to be designated as hedges. Accordingly, we recognize all changes in the fair values of our derivatives instruments, net, in our Condensed Consolidated Statement of Operations. Refer to Note 9.

Revenue recognition. Generally, we recognize revenue from product sales when goods are shipped and title and risk of loss transfer to our customers. Our estimates for sales returns and allowances are based upon the historical patterns of product returns and allowances taken, matched against the sales from which they originated, and management’s evaluation of specific factors that may increase or decrease the risk of product returns.

For the three months ended March 31, 2015 and 2014, revenue from services also includes $0.2 million and 0.1 million, respectively, of revenue related to our consulting agreement with Neovasc, Inc. (“Neovasc”) and to revenue related to molecular diagnostics collaboration agreements. We recognize this revenue on a straight-line basis over the contractual term of the agreements.

The assessment of our obligations and related performance periods requires significant management judgment. If an agreement contains research and development obligations, the relevant time period for the research and development phase is based on management estimates and could vary depending on the outcome of clinical trials and the regulatory approval process. Such changes could materially impact the revenue recognized, and as a result, management reviews the estimates related to the relevant time period of research and development on a quarterly basis. For the three months ended March 31, 2015, revenue from transfer of intellectual property includes $12.5 million of revenue related to the Pfizer Transaction. Refer to Note 12.

Total deferred revenue included in Accrued expenses and Other long-term liabilities was $288.8 million and $6.7 million at March 31, 2015 and December 31, 2014, respectively. The deferred revenue balance at March 31, 2015 relates primarily to the Pfizer Transaction. Refer to Note 12.

Allowance for doubtful accounts. We analyze accounts receivable balances by considering factors such as historical experience, customer credit worthiness, the age of accounts receivable balances and current economic conditions and trends that may affect a customer's ability to pay. The allowance for doubtful accounts is based on our assessment of the collectability of customer accounts. Our reported net loss is directly affected by our estimate of the collectability of accounts receivable. The amount of the allowance for doubtful accounts was $1.7 million and $1.9 million at March 31, 2015 and December 31, 2014, respectively.

Equity-based compensation. We measure the cost of employee services received in exchange for an award of equity instruments based on the grant-date fair value of the award. That cost is recognized in the Condensed Consolidated Statement of Operations over the period during which an employee is required to provide service in exchange for the award. We record excess tax benefits, realized from the exercise of stock options as a financing cash inflow rather than as a reduction of taxes paid in cash flow from operations. Equity-based compensation arrangements to non-employees are recorded at their fair value on the measurement date. The measurement of equity-based compensation to non-employees is subject to periodic adjustment as the underlying equity instruments vest. During the three months ended March 31, 2015 and 2014, we recorded $7.4 million and $3.6 million, respectively, of equity-based compensation expense.

Research and development expenses. Research and development expenses include external and internal expenses, partially offset by third-party grants and fundings arising from collaboration agreements. External expenses include clinical and non-clinical activities performed by contract research organizations, lab services, purchases of drug and diagnostic product materials and manufacturing development costs. Research and development employee-related expenses include salaries, benefits and stock-based compensation expense. Other unallocated internal research and development expenses are incurred to support overall research and development activities and include expenses related to general overhead and facilities. We expense these costs in the period in which they are incurred. We estimate our liabilities for research and development expenses in order to match the recognition of expenses to the period in which the actual services are received. As such, accrued liabilities related to third party research and development activities are recognized based upon our estimate of services received and degree of completion of the services in accordance with the specific third party contract.

Segment reporting. Our chief operating decision-maker (“CODM”) is Phillip Frost, M.D., our Chairman and Chief Executive Officer. Our CODM reviews our operating results and operating plans and makes resource allocation decisions on a Company-wide or aggregate basis. We currently manage our operations in two reportable segments, pharmaceuticals and diagnostics. The pharmaceutical segment consists of two operating segments, our (i) pharmaceutical research and development segment which is focused on the research and development of pharmaceutical products, and vaccines, and (ii) the pharmaceutical operations we acquired in Chile, Mexico, Israel, Spain, Uruguay and Brazil. The diagnostics segment consists of two operating segments, our (i) pathology operations we acquired through the acquisition of OPKO Lab and (ii) point-of-care and molecular diagnostics operations. There are no significant inter-segment sales. We evaluate the performance of each segment based on operating profit or loss. There is no inter-segment allocation of interest expense and income taxes.

Variable interest entities. The consolidation of variable interest entities (“VIE”) is required when an enterprise has a controlling financial interest. A controlling financial interest in a VIE will have both of the following characteristics: (a) the power to direct the activities of a VIE that most significantly impact the VIE’s economic performance and (b) the obligation to absorb losses of the VIE that could potentially be significant to the VIE. Refer to Note 5.

Investments. We have made strategic investments in development stage and emerging companies. We record these investments as equity method investments or investments available for sale based on our percentage of ownership and whether we have significant influence over the operations of the investees. For investments classified under the equity method of accounting, we record our proportionate share of their losses in Losses from investments in investees in our Condensed

Recent accounting pronouncements. In May 2014, the FASB issued Accounting Standards Update (“ASU”), ASU No. 2014-09, "Revenue from Contracts with Customers." ASU No. 2014-09 clarifies the principles for recognizing revenue and develops a common revenue standard for GAAP and International Financial Reporting Standards that removes inconsistencies and weaknesses in revenue requirements, provides a more robust framework for addressing revenue issues, improves comparability of revenue recognition practices across entities, industries, jurisdictions, and capital markets, provides more useful information to users of financial statements through improved disclosure requirements and simplifies the preparation of financial statements by reducing the number of requirements to which an entity must refer. ASU No. 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. Companies can choose to apply the ASU using either the full retrospective approach or a modified retrospective approach. We are currently evaluating both methods of adoption and the impact that the adoption of this ASU will have on our Condensed Consolidated Financial Statements.

Basic loss per share is computed by dividing our net loss by the weighted average number of shares outstanding during the period. Diluted loss per share is computed by dividing our net loss increased by dividends on preferred stock by the weighted average number of shares outstanding and the impact of all dilutive potential common shares, primarily stock options. The dilutive impact of stock options and warrants is determined by applying the “treasury stock” method. In the periods in which their effect would be antidilutive, no effect has been given to outstanding options, warrants or convertible Preferred Stock in the diluted computation. Potentially dilutive shares issuable pursuant to the 2033 Senior Notes (defined in Note 6) were not included in the computation of net loss per share for the three months ended March 31, 2015, because their inclusion would be antidilutive.

A total of 17,489,421 and 29,874,112 potential shares of Common Stock have been excluded from the calculation of diluted net loss per share for the three months ended March 31, 2015 and 2014, respectively, because their inclusion would be antidilutive.

During the three months ended March 31, 2015, 21,735,636 Common Stock options and Common Stock warrants to purchase shares of our Common Stock were exercised, resulting in the issuance of 20,529,027 shares of Common Stock. Of the 21,735,636 Common Stock options and Common Stock warrants exercised, 1,206,609 shares of Common Stock were surrendered in lieu of a cash payment via the net exercise feature of the agreements.

At March 31, 2015, the changes in value of the intangible assets and goodwill are primarily due to foreign currency fluctuations between the Chilean and Mexican pesos, the Euro and the Shekel against the U.S. dollar.

The following table reflects the changes in Goodwill during the three months ended March 31, 2015.

On April 17, 2014, we entered into a stock purchase agreement to acquire 100% of the issued and outstanding share capital of Inspiro Medical Ltd. (“Inspiro”), an Israeli medical device company developing a new platform to deliver small molecule drugs such as corticosteroids and beta agonists and larger molecules to treat respiratory diseases.     

In connection with the transaction, we paid $1.5 million in cash and delivered 999,556 shares of our Common Stock valued at $8.6 million based on the closing price per share of our Common Stock as reported by the NYSE on the actual closing date of the acquisition, or $8.57 per share. The transaction closed on May 22, 2014. The number of shares issued was based upon our trading price as reported by the NYSE for the ten trading days immediately preceding the execution date of the purchase agreement, or $9.00 per share.

Inspiro’s Inspiromatic™ is a “smart” easy-to-use dry powder inhaler with several advantages over existing devices. We anticipate that this innovative device will play a valuable role in the improvement of therapy for asthma, chronic obstructive pulmonary disease, cystic fibrosis and other respiratory diseases. We recorded the transaction as an asset acquisition and recorded the assets and liabilities at fair value. As the asset had no alternative future use, we recorded $10.1 million of acquired in-process research and development expenses.

The following table reflects the accounting method, carrying value and underlying equity in net assets of our unconsolidated investments as of March 31, 2015:

Our equity method investments consist of investments in Pharmsynthez (ownership 17%), Cocrystal Pharma, Inc. (“COCP”) (8%), Sevion Therapeutics, Inc. (“Sevion”) (4%), Non-Invasive Monitoring Systems, Inc. (1%) and Neovasc (5%). The total assets, liabilities, and net losses of our equity method investees for the three months ended March 31, 2015 were $373.4 million, $(51.0) million, and $(37.8) million, respectively. We have determined that we and/or our related parties can significantly influence the success of our equity method investments through our board representation and voting power. Accordingly, we account for our investment in these entities under the equity method. For investments classified under the equity method of accounting, we record our proportionate share of their losses in Loss from investments in investees in our Condensed Consolidated Statement of Operations. The aggregate value of our equity method investments based on the quoted market price of their common stock and the number of shares held by us as of March 31, 2015 is $112.1 million. See further discussion of our investment in Pharmsynthez below.

Our available for sale investments consist of investments in RXi Pharmaceuticals Corporation (“RXi”) (ownership 10%), ChromaDex Corporation (2%) and ARNO Therapeutics, Inc. (“ARNO”) (4%). We have determined that our ownership, along with that of our related parties, does not provide us with significant influence over the operations of our available for sale investments. Accordingly, we account for our investment in these entities as available for sale, and we record changes in these investments as an unrealized gain or loss in Other comprehensive income (loss) each reporting period.

Gains (losses) included in earnings from sales of our investments for the three months ended March 31, 2014 were $1.3 million and were recorded in Other income (expense), net in our Condensed Consolidated Statement of Operations. We did not

have any such activity in the three months ended March 31, 2015. The cost of securities sold is based on the specific identification method.

In addition to our equity method investments and available for sale investments, we hold options to purchase 1.0 million additional shares of Neovasc, which are fully vested as of December 31, 2014, and 1.0 million, 0.8 million and 0.1 million of warrants to purchase additional shares of COCP, ARNO and Sevion, respectively. We recorded the changes in the fair value of the options and warrants in Fair value changes of derivative instruments, net in our Consolidated Statements of Operations. We record the fair value of the options and warrants in Investments, net in our Consolidated Balance Sheets. See further discussion of the Company’s options and warrants in Note 8 and Note 9.

•We delivered approximately $9.6 million to Pharmsynthez.

•Pharmsynthez issued to us approximately 13.6 million of its common shares.

•Pharmsynthez agreed, at its option, to issue approximately 12.0 million common shares to us or to pay us cash in Russian Rubles (“RUR”) 265.0 million ($8.1 million at December 31, 2013) on or before December 31, 2013 (the “Pharmsynthez Note Receivable”). In January 2014, Pharmsynthez delivered to us approximately 12.0 million shares of its common stock in satisfaction of the Pharmsynthez Notes Receivable.

• We had a right to purchase additional shares in Pharmsynthez at a fixed price if Pharmsynthez pays us in cash rather than delivering to us the 12.0 million Pharmsynthez common shares (the “Purchase Option”), however in connection with the settlement of the Pharmsynthez Note Receivable in January 2014, this right terminated. 

• We granted rights to certain technologies in the Russian Federation, Ukraine, Belarus, Azerbaijan and Kazakhstan (the “Territories”) to Pharmsynthez. 

•We will receive from Pharmsynthez royalties on net sales of products incorporating the technologies in the Territories, as well as a percentage of any sublicense income from third parties for the technologies in the Territories.

•Pharmsynthez paid us $9.5 million under the various collaboration and funding agreements for the grant of rights and development of the technologies (the “Collaboration Payments”).

We have accounted for the license and development activities as a multi-element arrangement, and allocated the total arrangement consideration based on the relative selling prices of the elements. We record the allocated consideration for development activities as an offset to Research and development expenses over the three-year term of the Collaboration Payments.  We recorded revenue in connection with the grant of rights to the technologies proportionately as the payments were received. 

During the three months ended March 31, 2015 and 2014, we recorded $0 million and $0.5 million, respectively, in Revenue from transfer of intellectual property and $0.2 million and $0.4 million, respectively, as an offset to Research and development expenses related to the Collaboration Payments.

We acquired 840,000 shares of Zebra Series A-2 Preferred Stock and 900,000 shares of Zebra restricted common stock (ownership 27% at March 31, 2015). Zebra is a privately held biotechnology company focused on the discovery and development of biosuperior antibody therapeutics and complex drugs. Dr. Richard Lerner, M.D., a member of our Board of Directors, is a founder of Zebra and, along with Dr. Frost, serves as a member of Zebra’s Board of Directors.

In June 2012, we acquired a 50% stock ownership in SciVac (45% as of March 31, 2015) from FDS Pharma LLP (“FDS”). SciVac is a privately-held Israeli company that produces a third-generation hepatitis B-vaccine. From November 2012 until March 31, 2015, we loaned to SciVac a combined $6.6 million for working capital purposes. We have determined that we hold variable interests in SciVac based on our assessment that SciVac does not have sufficient resources to carry out its principal activities without financial support. In order to determine the fair market value of our investment in SciVac, we have utilized a business enterprise valuation approach.

In order to determine the primary beneficiary of SciVac, we evaluated our investment to identify if we had the power to direct the activities that most significantly impact the economic performance of SciVac. We have determined that the power to direct the activities that most significantly impact the economic performance of SciVac is conveyed through SciVac’s board of directors. SciVac’s board of directors appoint and oversee SciVac’s management team who carry out the activities that most significantly impact the economic performance of SciVac. As part of the share and debt purchase agreement, SciVac’s board of directors is constituted by 5 members, of which 3 members are appointed by us, representing 60% of SciVac’s board. Based on this analysis, we determined that we have the power to direct the activities of SciVac and as such we are the primary beneficiary. As a result of this conclusion, we have consolidated the results of operations and financial position of SciVac and recorded a reduction of equity for the portion of SciVac we do not own.

The following table represents the consolidated assets and non-recourse liabilities related to SciVac as of March 31, 2015 and December 31, 2014. These assets are owned by, and these liabilities are obligations of, SciVac, not us.

In March 2015, SciVac entered into an agreement pursuant to which Levon Resources Ltd. ("Levon") will acquire 100% of the issued and outstanding ordinary shares of SciVac by way of a court-approved plan of arrangement (the "Arrangement"). Upon closing, which is anticipated to occur in the second quarter of 2015, Levon intends to change its name to SciVac Inc. ("New SciVac"), and the current officers and directors of SciVac will be the officers and directors of New SciVac post-closing. The current owners of SciVac will own 68.4% of the outstanding shares of New SciVac post-closing, with OPKO owning approximately 30% of the outstanding shares.

NOTE 6 DEBT    

In January 2013, we entered into note purchase agreements (the “2033 Senior Notes”) with qualified institutional buyers and accredited investors (collectively the “Purchaser”) in a private placement in reliance on exemptions from registration under the Securities Act of 1933, (the “Securities Act”). The Purchasers of the 2033 Senior Notes include Frost Gamma Investments Trust, a trust affiliated with Dr. Frost, and Hsu Gamma Investment, L.P., an entity affiliated with Dr. Jane H. Hsiao, our Vice Chairman and Chief Technology Officer. The 2033 Senior Notes were issued on January 30, 2013. The 2033 Senior Notes, which total $175.0 million, bear interest at the rate of 3.00% per year, payable semiannually on February 1 and August 1 of each year, beginning August 1, 2013. The 2033 Senior Notes will mature on February 1, 2033, unless earlier repurchased, redeemed or converted. Upon a fundamental change as defined in the instruments governing the 2033 Senior Notes, subject to certain exceptions, the holders may require us to repurchase all or any portion of their 2033 Senior Notes for cash at a repurchase price equal to 100% of the principal amount of the 2033 Senior Notes being repurchased, plus any accrued and unpaid interest to but not including the fundamental change repurchase date.

The following table sets forth information related to the 2033 Senior Notes which is included our Condensed Consolidated Balance Sheets as of March 31, 2015:

The 2033 Senior Notes will be convertible at any time on or after November 1, 2032, through the second scheduled trading day immediately preceding the maturity date, at the option of the holders. Additionally, holders may convert their 2033 Senior Notes prior to the close of business on the scheduled trading day immediately preceding November 1, 2032, under the following circumstances: (1) conversion based upon satisfaction of the trading price condition relating to the 2033 Senior Notes; (2) conversion based on the Common Stock price; (3) conversion based upon the occurrence of specified corporate events; or (4) if we call the 2033 Senior Notes for redemption. The 2033 Senior Notes will be convertible into cash, shares of our Common Stock, or a combination of cash and shares of Common Stock, at our election unless we have made an irrevocable election of net share settlement. The initial conversion rate for the 2033 Senior Notes will be 141.48 shares of Common Stock per $1,000 principal amount of 2033 Senior Notes (equivalent to an initial conversion price of approximately $7.07 per share of Common Stock), and will be subject to adjustment upon the occurrence of certain events. In addition, we will, in certain circumstances, increase the conversion rate for holders who convert their 2033 Senior Notes in connection with a make-whole fundamental change (as defined in the Indenture) and holders who convert upon the occurrence of certain specific events prior to February 1, 2017 (other than in connection with a make-whole fundamental change). Holders of the 2033 Senior Notes may require us to repurchase the 2033 Senior Notes for 100% of their principal amount, plus accrued and unpaid interest, on February 1, 2019, February 1, 2023 and February 1, 2028, or following the occurrence of a fundamental change as defined in the indenture governing the 2033 Senior Notes. See further discussion in Note 14.

We may not redeem the 2033 Senior Notes prior to February 1, 2017. On or after February 1, 2017 and before February 1, 2019, we may redeem for cash any or all of the 2033 Senior Notes but only if the last reported sale price of our Common Stock exceeds 130% of the applicable conversion price for at least 20 trading days during the 30 consecutive trading day period ending on the trading day immediately prior to the date on which we deliver the redemption notice. The redemption price will equal 100% of the principal amount of the 2033 Senior Notes to be redeemed, plus any accrued and unpaid interest to but not including the redemption date. On or after February 1, 2019, we may redeem for cash any or all of the 2033 Senior Notes at a redemption price of 100% of the principal amount of the 2033 Senior Notes to be redeemed, plus any accrued and unpaid interest up to but not including the redemption date.

On August 30, 2013, one of the conversion rights in the 2033 Senior Notes was triggered. Holders of the 2033 Senior Notes converted $16.9 million principal amount into 2,396,145 shares of our Common Stock at a rate of 141.4827 shares of Common Stock per $1,000 principal amount of 2033 Senior Notes. In June 2014, we entered into an exchange agreement with a holder of the Company’s Notes pursuant to which such holder exchanged $70.4 million in aggregate principal amount of Notes for 10,974,431 shares of the Company’s Common Stock and approximately $0.8 million in cash representing accrued interest through the date of completion of the exchange.

In March 2015, we entered into exchange agreements with certain holders of our 2033 Senior Notes pursuant to which such holders exchanged $36.4 million in aggregate principal amount of 2033 Senior Notes for 5,363,896 shares of the Company’s Common Stock and approximately $0.2 million in cash representing accrued interest through the date of completion of the exchange. We recorded a $0.3 million non-cash loss related to the exchange. The loss on exchange is included within Other income (expense) on our Condensed Consolidated Statement of Operations.

The following table sets forth the fair value of the 2033 Senior Notes with and without the embedded derivatives, and the fair value of the embedded derivatives at March 31, 2015. At March 31, 2015 the principal amount of the 2033 Senior Notes was $51.2 million:

Changes in certain inputs into the lattice model can have a significant impact on changes in the estimated fair value of the embedded derivatives. For example, a decrease in our estimated credit spread results in an increase in the estimated value of the embedded derivatives. Conversely, a decrease in the price of our Common Stock results in a decrease in the estimated fair value of the embedded derivatives. For the three months ended March 31, 2015, we observed an increase in the market price of our Common Stock which primarily resulted in a $53.7 million increase in the estimated fair value of our embedded derivatives recorded in Fair value changes of derivative instruments, net in our Condensed Consolidated Statements of Operations.

We have line of credit agreements with eight financial institutions as of March 31, 2015 and twelve financial institutions as of December 31, 2014 in Chile and Spain. These lines of credit are used primarily as a source of working capital for inventory purchases.

At March 31, 2015 and December 31, 2014, the weighted average interest rate on our lines of credit was approximately 5.9% and 6.1%, respectively.

At March 31, 2015 and December 31, 2014, we had mortgage notes and other debt related to OPKO Health Europe as follows:

The mortgages and other debts mature at various dates ranging from 2015 through 2024 bearing variable interest rates from 2.7% up to 6.3%. The weighted average interest rate on the mortgage notes and other debt at March 31, 2015 and December 31, 2014, was 3.2% and 3.4%, respectively. The mortgages are secured by our office space in Barcelona.

For the three months ended March 31, 2015, changes in Accumulated other comprehensive income (loss), net of tax, were as follows: