on march 3 , 2017 , we entered into the vertex agreement with vertex , pursuant to which we agreed to sell and assign to vertex ctp-656 , now known as vx-561 , and other cystic fibrosis assets of ours for up to $ 250.0 million , subject to the satisfaction of certain closing conditions . on july 25 , 2017 , the transaction contemplated by the vertex agreement closed , and vertex paid us $ 160.0 million in cash consideration , with $ 16.0 million initially held in escrow , which was released to us in february 2019. additional information concerning the sale of ctp-656 is discussed in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. our operating results may fluctuate significantly from year to year , depending on the timing and magnitude of cash payments received pursuant to collaboration and licensing arrangements and other agreements and the timing and magnitude of clinical trial and other development activities under our current development programs . we generated net losses of $ 78.2 million and $ 56.0 million for the years ended december 31 , 2019 and 2018 , respectively . we expect to continue to incur significant expenses and operating losses for at least the next several years . we expect our expenses will increase substantially in connection with our ongoing activities as we continue research and development efforts and develop and conduct additional nonclinical studies and clinical trials with respect to our product candidates . 57 we do not expect to generate revenue from product sales unless and until we , or our collaborators , obtain marketing approval for one or more of our product candidates , which we expect will take a number of years and is subject to significant uncertainty . if we obtain , or believe that we are likely to obtain , marketing approval for any product candidates for which we retain commercialization rights , and intend to commercialize a product , we expect to incur significant commercialization expenses related to product sales , marketing , manufacturing and distribution . we expect to seek to fund our operations through a combination of equity offerings , debt financings , collaboration and licensing arrangements and other sources for at least the next several years . however , we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all . our failure to raise capital or enter into such other arrangements as and when needed would force us to delay , limit , reduce or terminate our research and development programs and could have a material adverse effect on our financial condition and our ability to develop our products . we will need to generate significant revenues to achieve sustained profitability and we may never do so . collaborations we have entered into a number of collaborations for the research , development and commercialization of deuterated compounds . to date , our collaborations have provided us with significant funding for both our specific development programs and our dce platform . our collaborators also have applied their considerable scientific , development , regulatory and commercial capabilities to the development of our compounds . in addition , in some instances , where we develop and seek to collaborate with respect to deuterated analogs of marketed drugs or of drug candidates that are more advanced in clinical trials , our collaborators may be eligible for an expedited development or regulatory pathway by relying on previous clinical data regarding their corresponding non-deuterated compound . we believe that our collaborations have contributed to our ability to progress our product candidates and build our dce platform . our collaborations are discussed further in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. asset purchase agreement on march 3 , 2017 , we entered into the vertex agreement pursuant to which we sold and assigned to vertex ctp-656 , now known as vx-561 , and other cystic fibrosis assets of ours . on july 25 , 2017 , the transaction contemplated by the vertex agreement closed , and vertex paid us $ 160.0 million in cash consideration , with $ 16.0 million initially held in escrow , which was released to us in february 2019. additional information concerning the sale of ctp-656 is discussed in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. additionally , upon the achievement of certain milestone events , vertex has agreed to pay us an aggregate of up to $ 90.0 million . of this amount , $ 50.0 million will become payable to us upon receipt of fda marketing approval for a combination treatment regimen containing ctp-656 for patients with cystic fibrosis , and $ 40.0 million will become payable to us upon completion of a pricing and reimbursement agreement in the first of the united kingdom , germany or france with respect to a combination treatment regimen containing ctp-656 for patients with cystic fibrosis . financial operations overview revenue we have not generated any revenue from the sales of products . all of our revenue to date has been generated through collaboration , license and research arrangements with collaborators and nonprofit organizations for the development and commercialization of product candidates , a patent assignment agreement and an asset sale . on january 1 , 2018 , we adopted financial accounting standards board , or fasb , accounting standards update , or asu , 2014-09 , revenue from contracts with customers , which is also referred to as accounting standards codification , or asc , 606. we adopted asc 606 using the modified retrospective approach . story_separator_special_tag 62 replace_table_token_2_th license and research and development revenue license and research and development revenue was $ 1.1 million for the year ended december 31 , 2019. the revenue recognized in 2019 was primarily a result of the license agreement , or the cipla agreement , entered into in the first quarter of 2019 with cipla technologies llc , or cipla . we recognized $ 1.0 million in revenue associated with this arrangement for the year ended december 31 , 2019. for additional details related to the cipla agreement , see note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. the decrease in license and research and development revenue compared to $ 10.5 million for the year ended december 31 , 2018 is due to the upfront consideration received from processa of 2,090,301 shares of its common stock with a fair value of $ 10.5 million on the date of the transaction , which was recorded in fiscal year 2018. for additional details related to the transaction with processa , see note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. as of december 31 , 2019 , we had deferred revenue of : $ 7.8 million related to our collaboration with celgene corporation , or celgene , consisting of $ 1.3 million related to the r & d services performance obligation , $ 0.1 million related to the supply performance obligation and $ 6.4 million related to the first and second discount performance obligations ; and $ 2.8 million related to a payment received from glaxosmithkline , or gsk . research and development expenses the following table summarizes our external research and development expenses , by program , for the year ended december 31 , 2019 , with our internal research expenses separately classified by category . replace_table_token_3_th research and development expenses were $ 59.8 million for the year ended december 31 , 2019. ctp-543 expenses primarily related to clinical development , including multiple phase 2 clinical trials . ctp-692 expenses were attributable to the phase 1 clinical trials completed in 2019 and manufacturing costs to support the advancement of the ctp-692 program into a phase 2 63 clinical trial . employee-related expenses consisted primarily of cash and non-cash stock-based compensation expenses . facility-related expenses consisted primarily of rent and maintenance of our premises . external costs for other programs includes a $ 0.5 million payment to the nonprofit organization fast forward in the first quarter of 2019 under an existing agreement related to ctp-354 between us and fast forward , which was triggered by the upfront payment pursuant to the cipla agreement , and costs incurred to develop our research pipeline . the $ 16.7 million increase in research and development costs for the year ended december 31 , 2019 compared to the year ended december 31 , 2018 is due to multiple ctp-543 phase 2 clinical trials , multiple ctp-692 phase 1 clinical trials and manufacturing costs to support the continued development of ctp-692 . general and administrative expenses the following table summarizes our general and administrative expenses for the year ended december 31 , 2019. year ended december 31 , ( in thousands ) 2019 employee salaries and benefits $ 11,000 external professional service and legal expenses 5,173 facility , technology and other expenses 3,797 depreciation and amortization 306 total general and administrative expenses $ 20,276 general and administrative expenses for the year ended december 31 , 2019 consisted primarily of salaries and related costs for personnel , including non-cash stock-based compensation . other general and administrative expenses included accounting and legal services , office and facility-related costs . total general and administrative expenses for the year ended december 31 , 2019 decreased by $ 2.7 million compared to the year ended december 31 , 2018. salaries and benefits decreased $ 1.7 million and legal costs decreased $ 0.8 million compared to the year ended december 31 , 2018. these decreases are slightly offset by an increase of $ 0.2 million in audit and other professional fees compared to the year ended december 31 , 2018. investment income investment income was $ 3.0 million for the year ended december 31 , 2019 and consisted of interest income earned on cash equivalents and investments . unrealized loss on marketable equity securities we recorded an unrealized loss on marketable equity securities of $ 2.2 million during the year ended december 31 , 2019. unrealized loss on marketable equity securities consists of changes in the fair value of shares of common stock of processa held by us , as discussed further in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. discussion of the year ended december 31 , 2018 the following table summarizes our results of operations for the year ended december 31 , 2018 . 64 replace_table_token_4_th license and research and development revenue license and research and development revenue was $ 10.5 million for the year ended december 31 , 2018. in 2018 , we granted processa an exclusive , worldwide , royalty-bearing license to develop , manufacture and commercialize ctp-499 in exchange for upfront consideration of 2,090,301 shares of common stock of processa with a fair value of $ 10.5 million on the date of the transaction , which was recorded as license and research and development revenue during fiscal year 2018. for further details related to our transaction with processa , refer to note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. research and development expenses the following table summarizes our external research and development expenses , by program , for the year ended december 31 , 2018 , with our internal research expenses separately classified by category . replace_table_token_5_th research and development expenses were $ 43.1 million for the year ended december 31 , 2018. ctp-543 expenses primarily related to ongoing phase 2 clinical study and manufacturing costs

liquidity and capital resources we have incurred cumulative losses and negative cash flows from operations since our inception in april 2006 , and as of december 31 , 2019 , we had an accumulated deficit of $ 194.7 million . we anticipate that we will continue to incur losses for at least the next several years . we expect that our research and development and general and administrative expenses will continue to increase and , as a result , we will need additional capital to fund our operations , which we may raise through a combination of equity offerings , debt financings , collaboration and licensing arrangements and other sources . we have financed our operations to date primarily through the public offering and private placement of our equity , debt financing and funding from collaborations and patent assignments . during february 2014 , we completed our initial public offering , or ipo , whereby we sold 6,649,690 shares of common stock at a price to the public of $ 14.00 per share , raising aggregate net proceeds of $ 83.1 million . during march 2015 , we sold 3,300,000 shares of common stock through an underwritten public offering at a price to the public of $ 15.15 per share , raising aggregate net proceeds of $ 46.7 million . during january 2020 , we completed an underwriting public offering pursuant to which we sold 5,735,283 shares of common stock at the public offering price of $ 9.92 per share .


 Write a concise suspicious activity report of the following text delimited by triple backquotes. Return your response as a formal report which covers the key points highlighting the location,dates,entity names and account holder information in chronological order of the text.
     ```liquidity and capital resources we have incurred cumulative losses and negative cash flows from operations since our inception in april 2006 , and as of december 31 , 2019 , we had an accumulated deficit of $ 194.7 million . we anticipate that we will continue to incur losses for at least the next several years . we expect that our research and development and general and administrative expenses will continue to increase and , as a result , we will need additional capital to fund our operations , which we may raise through a combination of equity offerings , debt financings , collaboration and licensing arrangements and other sources . we have financed our operations to date primarily through the public offering and private placement of our equity , debt financing and funding from collaborations and patent assignments . during february 2014 , we completed our initial public offering , or ipo , whereby we sold 6,649,690 shares of common stock at a price to the public of $ 14.00 per share , raising aggregate net proceeds of $ 83.1 million . during march 2015 , we sold 3,300,000 shares of common stock through an underwritten public offering at a price to the public of $ 15.15 per share , raising aggregate net proceeds of $ 46.7 million . during january 2020 , we completed an underwriting public offering pursuant to which we sold 5,735,283 shares of common stock at the public offering price of $ 9.92 per share .
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 Suspicious Activity Report : on march 3 , 2017 , we entered into the vertex agreement with vertex , pursuant to which we agreed to sell and assign to vertex ctp-656 , now known as vx-561 , and other cystic fibrosis assets of ours for up to $ 250.0 million , subject to the satisfaction of certain closing conditions . on july 25 , 2017 , the transaction contemplated by the vertex agreement closed , and vertex paid us $ 160.0 million in cash consideration , with $ 16.0 million initially held in escrow , which was released to us in february 2019. additional information concerning the sale of ctp-656 is discussed in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. our operating results may fluctuate significantly from year to year , depending on the timing and magnitude of cash payments received pursuant to collaboration and licensing arrangements and other agreements and the timing and magnitude of clinical trial and other development activities under our current development programs . we generated net losses of $ 78.2 million and $ 56.0 million for the years ended december 31 , 2019 and 2018 , respectively . we expect to continue to incur significant expenses and operating losses for at least the next several years . we expect our expenses will increase substantially in connection with our ongoing activities as we continue research and development efforts and develop and conduct additional nonclinical studies and clinical trials with respect to our product candidates . 57 we do not expect to generate revenue from product sales unless and until we , or our collaborators , obtain marketing approval for one or more of our product candidates , which we expect will take a number of years and is subject to significant uncertainty . if we obtain , or believe that we are likely to obtain , marketing approval for any product candidates for which we retain commercialization rights , and intend to commercialize a product , we expect to incur significant commercialization expenses related to product sales , marketing , manufacturing and distribution . we expect to seek to fund our operations through a combination of equity offerings , debt financings , collaboration and licensing arrangements and other sources for at least the next several years . however , we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all . our failure to raise capital or enter into such other arrangements as and when needed would force us to delay , limit , reduce or terminate our research and development programs and could have a material adverse effect on our financial condition and our ability to develop our products . we will need to generate significant revenues to achieve sustained profitability and we may never do so . collaborations we have entered into a number of collaborations for the research , development and commercialization of deuterated compounds . to date , our collaborations have provided us with significant funding for both our specific development programs and our dce platform . our collaborators also have applied their considerable scientific , development , regulatory and commercial capabilities to the development of our compounds . in addition , in some instances , where we develop and seek to collaborate with respect to deuterated analogs of marketed drugs or of drug candidates that are more advanced in clinical trials , our collaborators may be eligible for an expedited development or regulatory pathway by relying on previous clinical data regarding their corresponding non-deuterated compound . we believe that our collaborations have contributed to our ability to progress our product candidates and build our dce platform . our collaborations are discussed further in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. asset purchase agreement on march 3 , 2017 , we entered into the vertex agreement pursuant to which we sold and assigned to vertex ctp-656 , now known as vx-561 , and other cystic fibrosis assets of ours . on july 25 , 2017 , the transaction contemplated by the vertex agreement closed , and vertex paid us $ 160.0 million in cash consideration , with $ 16.0 million initially held in escrow , which was released to us in february 2019. additional information concerning the sale of ctp-656 is discussed in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. additionally , upon the achievement of certain milestone events , vertex has agreed to pay us an aggregate of up to $ 90.0 million . of this amount , $ 50.0 million will become payable to us upon receipt of fda marketing approval for a combination treatment regimen containing ctp-656 for patients with cystic fibrosis , and $ 40.0 million will become payable to us upon completion of a pricing and reimbursement agreement in the first of the united kingdom , germany or france with respect to a combination treatment regimen containing ctp-656 for patients with cystic fibrosis . financial operations overview revenue we have not generated any revenue from the sales of products . all of our revenue to date has been generated through collaboration , license and research arrangements with collaborators and nonprofit organizations for the development and commercialization of product candidates , a patent assignment agreement and an asset sale . on january 1 , 2018 , we adopted financial accounting standards board , or fasb , accounting standards update , or asu , 2014-09 , revenue from contracts with customers , which is also referred to as accounting standards codification , or asc , 606. we adopted asc 606 using the modified retrospective approach . story_separator_special_tag 62 replace_table_token_2_th license and research and development revenue license and research and development revenue was $ 1.1 million for the year ended december 31 , 2019. the revenue recognized in 2019 was primarily a result of the license agreement , or the cipla agreement , entered into in the first quarter of 2019 with cipla technologies llc , or cipla . we recognized $ 1.0 million in revenue associated with this arrangement for the year ended december 31 , 2019. for additional details related to the cipla agreement , see note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. the decrease in license and research and development revenue compared to $ 10.5 million for the year ended december 31 , 2018 is due to the upfront consideration received from processa of 2,090,301 shares of its common stock with a fair value of $ 10.5 million on the date of the transaction , which was recorded in fiscal year 2018. for additional details related to the transaction with processa , see note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. as of december 31 , 2019 , we had deferred revenue of : $ 7.8 million related to our collaboration with celgene corporation , or celgene , consisting of $ 1.3 million related to the r & d services performance obligation , $ 0.1 million related to the supply performance obligation and $ 6.4 million related to the first and second discount performance obligations ; and $ 2.8 million related to a payment received from glaxosmithkline , or gsk . research and development expenses the following table summarizes our external research and development expenses , by program , for the year ended december 31 , 2019 , with our internal research expenses separately classified by category . replace_table_token_3_th research and development expenses were $ 59.8 million for the year ended december 31 , 2019. ctp-543 expenses primarily related to clinical development , including multiple phase 2 clinical trials . ctp-692 expenses were attributable to the phase 1 clinical trials completed in 2019 and manufacturing costs to support the advancement of the ctp-692 program into a phase 2 63 clinical trial . employee-related expenses consisted primarily of cash and non-cash stock-based compensation expenses . facility-related expenses consisted primarily of rent and maintenance of our premises . external costs for other programs includes a $ 0.5 million payment to the nonprofit organization fast forward in the first quarter of 2019 under an existing agreement related to ctp-354 between us and fast forward , which was triggered by the upfront payment pursuant to the cipla agreement , and costs incurred to develop our research pipeline . the $ 16.7 million increase in research and development costs for the year ended december 31 , 2019 compared to the year ended december 31 , 2018 is due to multiple ctp-543 phase 2 clinical trials , multiple ctp-692 phase 1 clinical trials and manufacturing costs to support the continued development of ctp-692 . general and administrative expenses the following table summarizes our general and administrative expenses for the year ended december 31 , 2019. year ended december 31 , ( in thousands ) 2019 employee salaries and benefits $ 11,000 external professional service and legal expenses 5,173 facility , technology and other expenses 3,797 depreciation and amortization 306 total general and administrative expenses $ 20,276 general and administrative expenses for the year ended december 31 , 2019 consisted primarily of salaries and related costs for personnel , including non-cash stock-based compensation . other general and administrative expenses included accounting and legal services , office and facility-related costs . total general and administrative expenses for the year ended december 31 , 2019 decreased by $ 2.7 million compared to the year ended december 31 , 2018. salaries and benefits decreased $ 1.7 million and legal costs decreased $ 0.8 million compared to the year ended december 31 , 2018. these decreases are slightly offset by an increase of $ 0.2 million in audit and other professional fees compared to the year ended december 31 , 2018. investment income investment income was $ 3.0 million for the year ended december 31 , 2019 and consisted of interest income earned on cash equivalents and investments . unrealized loss on marketable equity securities we recorded an unrealized loss on marketable equity securities of $ 2.2 million during the year ended december 31 , 2019. unrealized loss on marketable equity securities consists of changes in the fair value of shares of common stock of processa held by us , as discussed further in note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. discussion of the year ended december 31 , 2018 the following table summarizes our results of operations for the year ended december 31 , 2018 . 64 replace_table_token_4_th license and research and development revenue license and research and development revenue was $ 10.5 million for the year ended december 31 , 2018. in 2018 , we granted processa an exclusive , worldwide , royalty-bearing license to develop , manufacture and commercialize ctp-499 in exchange for upfront consideration of 2,090,301 shares of common stock of processa with a fair value of $ 10.5 million on the date of the transaction , which was recorded as license and research and development revenue during fiscal year 2018. for further details related to our transaction with processa , refer to note 12 to the consolidated financial statements appearing elsewhere in this annual report on form 10-k. research and development expenses the following table summarizes our external research and development expenses , by program , for the year ended december 31 , 2018 , with our internal research expenses separately classified by category . replace_table_token_5_th research and development expenses were $ 43.1 million for the year ended december 31 , 2018. ctp-543 expenses primarily related to ongoing phase 2 clinical study and manufacturing costs

