Derecognition of Business	6 Months Ended
Jun. 30, 2022
Discontinued Operations and Disposal Groups [Abstract]
Derecognition of Business	3. Derecognition of Business Arrangement Summary On November 1, 2021, the Company entered into an Asset Purchase Agreement ("APA") with Lonza Rockland, Inc. ("Lonza"). Under the terms of the APA, Lonza acquired all of the assets, properties and rights related to the Company’s business of manufacturing exosomes for use in clinical and non-clinical studies and the associated laboratory facility, with the exception of any activities associated with exosome modification and formulation. The closing of the transactions contemplated by the APA (the "Lonza Closing") occurred on November 15, 2021. In connection with the Lonza Closing, certain specialized manufacturing and quality personnel of the Company became employees of Lonza (the "Transferred Employees"). In connection with the Lonza Closing, the Company entered into a Manufacturing Services Agreement ("MSA") with Lonza which became effective on November 15, 2021. Pursuant to the terms of the MSA, Lonza became the exclusive manufacturing partner for the production of the Company’s exosome products, subject to limited exceptions. As consideration for the transactions contemplated by the APA and the associated ancillary agreements, the Company is entitled to approximately $65.0 million worth of exosome manufacturing services for its clinical programs during the next four years. To the extent the Company elects to use any free and/or discounted manufacturing services available under the MSA, it would be responsible for bearing any accompanying materials costs, external costs and a handling fee. Lonza is permitted to terminate the MSA with 12 months advance notice provided at any time after November 15, 2023. Accordingly, the Company’s ability to utilize the free and discounted manufacturing services available under the MSA in periods beyond November 15, 2024 is subject to Lonza’s right to terminate. The MSA may also be terminated upon the occurrence of certain other events, including customary termination provisions. Concurrently with the Lonza Closing, the Company and Lonza executed a License and Collaboration Agreement (the "License Agreement") on November 15, 2021. Pursuant to the terms of the License Agreement, the Company granted to Lonza an exclusive, worldwide, perpetual and sublicensable license to its high-throughput exosome manufacturing intellectual property in the contract development and manufacturing field. The Company is eligible to receive from Lonza a double-digit percentage of future sublicensing revenues per the terms of the License Agreement. No sublicensing revenue had been received by the Company or earned by Lonza as of June 30, 2022. Also contemporaneous with the Lonza Closing, the Company and Lonza entered into a Sublease Agreement (the "Sublease Agreement"), pursuant to which Lonza subleased the premises at which the Company’s exosome manufacturing operations were located. The initial lease term commenced on November 15, 2021 and continues through November 30, 2024. Under the terms of the Sublease Agreement, Lonza is obligated to pay the Company approximately $1.0 million of fixed rent charges per year, subject to a 2.8% annual increase, plus certain operating expenses and other costs. The Company retained the primary obligation under the original lease upon execution of the Sublease Agreement. Upon termination of the MSA on or prior to December 31, 2025, some aspects of the transactions contemplated by the APA and related ancillary agreements are required to be reverted, including with respect to certain assets, properties and rights that were transferred to Lonza. Upon termination or expiration of the Sublease Agreement at any time after December 31, 2025, some aspects of the transactions contemplated by the APA and related ancillary agreements are subject to potential reversion at Lonza’s option, including with respect to certain assets, properties and rights that were transferred to Lonza. Accounting Analysis The APA and pertinent elements of the MSA, the License Agreement and the Sublease Agreement comprise a single transaction because they were entered into in contemplation of one another and designed to achieve an overall commercial effect. Together, the related transactions consummated amongst the multiple contracts culminate in the transfer of the Company’s exosome manufacturing operations to Lonza (the "Lonza Transfer Transaction"). The Lonza Transfer Transaction represents the disposition of a business. Accordingly, the Company applied the derecognition guidance in ASC 810 in accounting for the transaction since Lonza is not a customer for any aspect of the arrangement. The Company’s control over the exosome manufacturing business transferred to Lonza was lost upon the closing of the APA and related ancillary agreements on November 15, 2021. Therefore, the Company recognized a gain upon derecognition on November 15, 2021. The gain was calculated as the difference between: (i) the fair value of the non-cash consideration and (ii) the carrying amount of the underlying group of assets. Because Lonza is entitled to terminate the MSA for any or no reason with 12 months’ notice after November 15, 2023, the Company determined that any non-cash consideration scheduled beyond November 15, 2024 is contingent consideration since its ability to utilize the associated free and discounted manufacturing services is subject to Lonza’s right to terminate. The Company also treated the sublicensing revenue that may become payable under the License Agreement as contingent consideration as the receipt of any such amounts is dependent on Lonza engaging in sublicensing transactions, which is not expected to be material. Neither of the elements of contingent consideration is required to be accounted for as a derivative instrument because either the payments do not meet the definition of a derivative or qualify for a scope exception from derivative accounting. Consequently, the consideration attributable to the Lonza Transfer Transaction is limited to the non-cash consideration due to the Company under the MSA and the sublicensing fees to which the Company is entitled under the License Agreement. The Company recorded the aggregate consideration, including the contingent consideration, at its fair value as of November 15, 2021. The aggregate fair value of the non-cash consideration represents the total discounted cash flows associated with the manufacturing expenditures expected to be avoided over the period the free and discounted services are available. The value of the costs that would otherwise be incurred was determined in reference to comparable costs charged by unrelated third parties. The Company also incorporated a breakage factor in deriving the estimated fair value of the non-cash consideration to reflect expectations around utilization by the Company and termination by Lonza. The Company classified the MSA as a Level 3 fair value measurement at the date of the closing of the transaction. The discounted cash flow approach relies primarily on Level 3 unobservable inputs, whereby expected future cash flows are discounted using a rate that includes assumptions regarding an entity’s average cost of debt and equity, incorporates expected future cash flows based on internal business plans, and applies certain assumptions about risk and uncertainties. As of November 15, 2021, the Company estimated the aggregate fair value of such non-cash consideration, including the associated contingent consideration, to be approximately $39.2 million. The Company does not expect to earn any significant sublicensing fees or other consideration from the transaction. Amounts payable under the Sublease Agreement based on the contractually stated rates approximate the fair value of the associated rights conveyed as of November 15, 2021. Therefore, the Company has accounted for the Sublease Agreement separately from the disposition of the business. No amount has been allocated from the other consideration in the arrangement to this element. The Company has recorded the aggregate fair value of the non-cash consideration as a prepaid manufacturing services asset as of November 15, 2021. The Company will amortize the prepaid manufacturing services asset as requested services are rendered by Lonza under the MSA, subject to impairment assessments. Such amount is classified as current or noncurrent based on the timing of when the associated services are expected to be utilized by the Company. Amounts expected to be consumed within the 12 months following June 30, 2022 are classified within current assets as prepaid manufacturing services as of June 30, 2022, while the remainder was classified as a noncurrent asset as of June 30, 2022. The Company has utilized $0.5 million of the prepaid manufacturing services for preliminary work as of June 30, 2022.

Derecognition of Business

6 Months Ended

Jun. 30, 2022

Discontinued Operations and Disposal Groups [Abstract]

3. Derecognition of Business

Arrangement Summary

On November 1, 2021, the Company entered into an Asset Purchase Agreement ("APA") with Lonza Rockland, Inc. ("Lonza"). Under the terms of the APA, Lonza acquired all of the assets, properties and rights related to the Company’s business of manufacturing exosomes for use in clinical and non-clinical studies and the associated laboratory facility, with the exception of any activities associated with exosome modification and formulation. The closing of the transactions contemplated by the APA (the "Lonza Closing") occurred on November 15, 2021. In connection with the Lonza Closing, certain specialized manufacturing and quality personnel of the Company became employees of Lonza (the "Transferred Employees").

In connection with the Lonza Closing, the Company entered into a Manufacturing Services Agreement ("MSA") with Lonza which became effective on November 15, 2021. Pursuant to the terms of the MSA, Lonza became the exclusive manufacturing partner for the production of the Company’s exosome products, subject to limited exceptions. As consideration for the transactions contemplated by the APA and the associated ancillary agreements, the Company is entitled to approximately $65.0 million worth of exosome manufacturing services for its clinical programs during the next four years. To the extent the Company elects to use any free and/or discounted manufacturing services available under the MSA, it would be responsible for bearing any accompanying materials costs, external costs and a handling fee. Lonza is permitted to terminate the MSA with 12 months advance notice provided at any time after November 15, 2023. Accordingly, the Company’s ability to utilize the free and discounted manufacturing services available under the MSA in periods beyond November 15, 2024 is subject to Lonza’s right to terminate. The MSA may also be terminated upon the occurrence of certain other events, including customary termination provisions.

Concurrently with the Lonza Closing, the Company and Lonza executed a License and Collaboration Agreement (the "License Agreement") on November 15, 2021. Pursuant to the terms of the License Agreement, the Company granted to Lonza an exclusive, worldwide, perpetual and sublicensable license to its high-throughput exosome manufacturing intellectual property in the contract development and manufacturing field. The Company is eligible to receive from Lonza a double-digit percentage of future sublicensing revenues per the terms of the License Agreement. No sublicensing revenue had been received by the Company or earned by Lonza as of June 30, 2022.

Also contemporaneous with the Lonza Closing, the Company and Lonza entered into a Sublease Agreement (the "Sublease Agreement"), pursuant to which Lonza subleased the premises at which the Company’s exosome manufacturing operations were located. The initial lease term commenced on November 15, 2021 and continues through November 30, 2024. Under the terms of the Sublease Agreement, Lonza is obligated to pay the Company approximately $1.0 million of fixed rent charges per year, subject to a 2.8% annual increase, plus certain operating expenses and other costs. The Company retained the primary obligation under the original lease upon execution of the Sublease Agreement.

Upon termination of the MSA on or prior to December 31, 2025, some aspects of the transactions contemplated by the APA and related ancillary agreements are required to be reverted, including with respect to certain assets, properties and rights that were transferred to Lonza. Upon termination or expiration of the Sublease Agreement at any time after December 31, 2025, some aspects of the transactions contemplated by the APA and related ancillary agreements are subject to potential reversion at Lonza’s option, including with respect to certain assets, properties and rights that were transferred to Lonza.

Accounting Analysis

The APA and pertinent elements of the MSA, the License Agreement and the Sublease Agreement comprise a single transaction because they were entered into in contemplation of one another and designed to achieve an overall commercial effect. Together, the related transactions consummated amongst the multiple contracts culminate in the transfer of the Company’s exosome manufacturing operations to Lonza (the "Lonza Transfer Transaction").

The Lonza Transfer Transaction represents the disposition of a business. Accordingly, the Company applied the derecognition guidance in ASC 810 in accounting for the transaction since Lonza is not a customer for any aspect of the arrangement. The Company’s control over the exosome manufacturing business transferred to Lonza was lost upon the closing of the APA and related ancillary agreements on November 15, 2021. Therefore, the Company recognized a gain upon derecognition on November 15, 2021.

The gain was calculated as the difference between: (i) the fair value of the non-cash consideration and (ii) the carrying amount of the underlying group of assets. Because Lonza is entitled to terminate the MSA for any or no reason with 12 months’ notice after November 15, 2023, the Company determined that any non-cash consideration scheduled beyond November 15, 2024 is contingent consideration since its ability to utilize the associated free and discounted manufacturing services is subject to Lonza’s right to terminate. The Company also treated the sublicensing revenue that may become payable under the License Agreement as contingent consideration as the receipt of any such amounts is dependent on Lonza engaging in sublicensing transactions, which is not expected to be material. Neither of the elements of contingent consideration is required to be accounted for as a derivative instrument because either the payments do not meet the definition of a derivative or qualify for a scope exception from derivative accounting.

Consequently, the consideration attributable to the Lonza Transfer Transaction is limited to the non-cash consideration due to the Company under the MSA and the sublicensing fees to which the Company is entitled under the License Agreement. The Company recorded the aggregate consideration, including the contingent consideration, at its fair value as of November 15, 2021. The aggregate fair value of the non-cash consideration represents the total discounted cash flows associated with the manufacturing expenditures expected to be avoided over the period the free and discounted services are available. The value of the costs that would otherwise be incurred was determined in reference to comparable costs charged by unrelated third parties. The Company also incorporated a breakage factor in deriving the estimated fair value of the non-cash consideration to reflect expectations around utilization by the Company and termination by Lonza. The Company classified the MSA as a Level 3 fair value measurement at the date of the closing of the transaction. The discounted cash flow approach relies primarily on Level 3 unobservable inputs, whereby expected future cash flows are discounted using a rate that includes assumptions regarding an entity’s average cost of debt and equity, incorporates expected future cash flows based on internal business plans, and applies certain assumptions about risk and uncertainties. As of November 15, 2021, the Company estimated the aggregate fair value of such non-cash consideration, including the associated contingent consideration, to be approximately $39.2 million. The Company does not expect to earn any significant sublicensing fees or other consideration from the transaction.

Amounts payable under the Sublease Agreement based on the contractually stated rates approximate the fair value of the associated rights conveyed as of November 15, 2021. Therefore, the Company has accounted for the Sublease Agreement separately from the disposition of the business. No amount has been allocated from the other consideration in the arrangement to this element.

The Company has recorded the aggregate fair value of the non-cash consideration as a prepaid manufacturing services asset as of November 15, 2021. The Company will amortize the prepaid manufacturing services asset as requested services are rendered by Lonza under the MSA, subject to impairment assessments. Such amount is classified as current or noncurrent based on the timing of when the associated services are expected to be utilized by the Company. Amounts expected to be consumed within the 12 months following June 30, 2022 are classified within current assets as prepaid manufacturing services as of June 30, 2022, while the remainder was classified as a noncurrent asset as of June 30, 2022. The Company has utilized $0.5 million of the prepaid manufacturing services for preliminary work as of June 30, 2022.